feat(terminal): port render state, highlights and the formatter

- render.rs ports render.zig: RenderState, the per-frame snapshot the
  renderer consumes (rows, cells, styles, graphemes, selection,
  highlights, cursor, colors), updated incrementally with Zig's full
  redraw triggers and per-page/per-row dirty tracking. Cells are stored
  struct-of-arrays; use the accessors.
- highlight.rs ports highlight.zig (untracked, tracked, flattened).
- formatter.rs ports formatter.zig: plain, VT and HTML output for
  terminal, screen, page list and page, with selection, rectangle,
  unwrap, trim, palette, codepoint maps, hyperlinks and pin/point maps.
  Screen's test dump helpers now delegate to it.

Cargo.toml also picks up dependencies for the kitty graphics and search
modules that are being ported concurrently.

Test Plan:
- cargo test -p ghostty-terminal --lib (1243 passed; formatter 100/100,
  render 15/15 Zig tests)

crates/ghostty-terminal/src/formatter.rs

@@ -0,0 +1,1581 @@
+//! Terminal state formatters: plain text, VT (with styles) and HTML.
+//!
+//! Port of `ZIG/src/terminal/formatter.zig`.
+//!
+//! Writers are `&mut dyn std::io::Write`; use the `format_string` helpers (or
+//! write into a `Vec<u8>`) for in-memory output. Where Zig used a
+//! `Discarding` writer to count bytes (for pin maps), the Rust port renders
+//! into a small scratch buffer and measures it.
+#![allow(clippy::too_many_arguments)]
+
+use crate::{
+    highlight::pin_page_iterator,
+    hyperlink::HyperlinkId,
+    page::{Cell, ContentTag, Page, Wide},
+    page_list::{PageList, Pin},
+    point::{Coordinate, Tag},
+    screen::Screen,
+    selection::Selection,
+    size,
+    style::{Color, Style},
+    terminal::Terminal,
+};
+use ghostty_vt::{
+    charsets::{Charset, Slots},
+    color::{Palette, Rgb},
+    modes::ENTRIES,
+};
+use std::io::{self, Write};
+
+type Result<T> = io::Result<T>;
+
+/// Formats available.
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum Format {
+    /// Plain text.
+    Plain,
+
+    /// Include VT sequences to preserve colors, styles, URLs, etc.
+    /// This is predominantly SGR sequences but may contain others as needed.
+    ///
+    /// Note that for reference colors, like palette indices, this will
+    /// vary based on the formatter and you should see the docs. For example,
+    /// PageFormatter with VT will emit SGR sequences with palette indices,
+    /// not the color itself.
+    ///
+    /// For VT, newlines will be emitted as `\r\n` so that the cursor properly
+    /// moves back to the beginning prior emitting follow-up lines.
+    Vt,
+
+    /// HTML output.
+    ///
+    /// This will emit inline styles for as much styling as possible,
+    /// in the interest of simplicity and ease of editing. This isn't meant
+    /// to build the most beautiful or efficient HTML, but rather to be
+    /// stylistically correct.
+    ///
+    /// For colors, RGB values are emitted as inline CSS (#RRGGBB) while palette
+    /// indices use CSS variables (var(--vt-palette-N)). The palette colors are
+    /// emitted by TerminalFormatter.Extra.palette as a <style> block if you
+    /// want to also include that. But if you only format a screen or lower,
+    /// the formatter doesn't have access to the current palette to render it.
+    ///
+    /// Newlines are emitted as actual '\n' characters. Consumers should use
+    /// CSS white-space: pre or pre-wrap to preserve spacing and alignment.
+    Html,
+}
+
+impl Format {
+    pub fn styled(self) -> bool {
+        match self {
+            Format::Plain => false,
+            Format::Html | Format::Vt => true,
+        }
+    }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub struct CodepointMap {
+    /// Unicode codepoint range to replace.
+    /// Asserts: range[0] <= range[1]
+    pub range: [u32; 2],
+
+    /// Replacement value for this range.
+    pub replacement: Replacement,
+}
+
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub enum Replacement {
+    /// A single replacement codepoint.
+    Codepoint(u32),
+
+    /// A string to replace with.
+    String(String),
+}
+
+/// Common encoding options regardless of what exact formatter is used.
+#[derive(Debug, Clone)]
+pub struct Options {
+    /// The format to emit.
+    pub emit: Format,
+
+    /// Whether to unwrap soft-wrapped lines. If false, this will emit the
+    /// screen contents as it is rendered on the page in the given size.
+    pub unwrap: bool,
+
+    /// Trim trailing whitespace on lines with other text. Trailing blank
+    /// lines are always trimmed. This only affects trailing whitespace
+    /// on rows that have at least one other cell with text. Whitespace
+    /// is currently only space characters (0x20).
+    pub trim: bool,
+
+    /// Replace matching Unicode codepoints with some other values.
+    /// This will use the last matching range found in the list.
+    pub codepoint_map: Option<Vec<CodepointMap>>,
+
+    /// Set a background and foreground color to use for the "screen".
+    /// For styled formats, this will emit the proper sequences or styles.
+    pub background: Option<Rgb>,
+    pub foreground: Option<Rgb>,
+
+    /// If set, then styled formats in `emit` will use this palette to
+    /// emit colors directly as RGB. If this is None, styled formats will
+    /// still work but will use deferred palette styling (e.g. CSS variables
+    /// for HTML or the actual palette indexes for VT).
+    pub palette: Option<Palette>,
+}
+
+impl Options {
+    pub fn new(emit: Format) -> Options {
+        Options {
+            emit,
+            unwrap: false,
+            trim: true,
+            codepoint_map: Some(Vec::new()),
+            background: None,
+            foreground: None,
+            palette: None,
+        }
+    }
+
+    pub fn plain() -> Options {
+        Options::new(Format::Plain)
+    }
+
+    pub fn vt() -> Options {
+        Options::new(Format::Vt)
+    }
+
+    pub fn html() -> Options {
+        Options::new(Format::Html)
+    }
+}
+
+/// Maps byte positions in formatted output to PageList pins.
+///
+/// Used by formatters that operate on PageLists to track the source position
+/// of each byte written. (Zig: `PinMap{alloc, map}`; here simply the vector to
+/// append to.)
+pub type PinMap<'a> = &'a mut Vec<Pin>;
+
+fn hex(rgb: Rgb) -> String {
+    format!("{:02x}{:02x}{:02x}", rgb.r, rgb.g, rgb.b)
+}
+
+fn invalid_cp() -> io::Error {
+    io::Error::new(io::ErrorKind::InvalidData, "invalid codepoint")
+}
+
+fn clone_pin(p: Pin) -> Pin {
+    Pin {
+        node: p.node,
+        x: p.x,
+        y: p.y,
+        garbage: false,
+    }
+}
+
+/// Append `count` copies of the last pin in `map` (or the top-left of the
+/// screen when empty).
+fn map_pad_last_or_top(map: &mut Vec<Pin>, pages: &PageList, count: usize) {
+    let pin = match map.last() {
+        Some(last) => clone_pin(*last),
+        None => pages.get_top_left(Tag::Screen).expect("top left"),
+    };
+    map.extend(std::iter::repeat_n(pin, count));
+}
+
+/// Terminal formatter formats the active terminal screen.
+///
+/// This will always only emit data related to the currently active screen.
+/// If you want to emit data for a specific screen (e.g. primary vs alt), then
+/// switch to that screen in the terminal prior to using this.
+///
+/// If you want to emit data for all screens (a less common operation), then
+/// you must create a no-content TerminalFormatter followed by multiple
+/// explicit ScreenFormatter calls. This isn't a common operation so this
+/// little extra work should be acceptable.
+///
+/// For styled formatting, this will emit the palette colors at the
+/// beginning so that the output can be rendered properly according to
+/// the current terminal state.
+pub struct TerminalFormatter<'a> {
+    /// The terminal to format.
+    pub terminal: &'a Terminal,
+
+    /// The common options
+    pub opts: Options,
+
+    /// The content to include.
+    pub content: Content,
+
+    /// Extra stuff to emit, such as terminal modes, palette, cursor, etc.
+    /// This information is ONLY emitted when the format is "vt".
+    pub extra: TerminalExtra,
+
+    /// If non-null, then `map` will contain the Pin of every byte
+    /// byte written to the writer offset by the byte index.
+    ///
+    /// Note that some emitted bytes may not correspond to any Pin, such as
+    /// the extra data around terminal state (palette, modes, etc.). For these,
+    /// we'll map it to the most previous pin so there is some continuity but
+    /// its an arbitrary choice.
+    ///
+    /// Warning: there is a significant performance hit to track this
+    pub pin_map: Option<PinMap<'a>>,
+}
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub struct TerminalExtra {
+    /// Emit the palette using OSC 4 sequences.
+    pub palette: bool,
+
+    /// Emit terminal modes that differ from their defaults using CSI h/l
+    /// sequences. Defaults are according to the Ghostty defaults which
+    /// are generally match most terminal defaults. This will include
+    /// things like current screen, bracketed mode, mouse event reporting,
+    /// etc.
+    pub modes: bool,
+
+    /// Emit scrolling region state using DECSTBM and DECSLRM sequences.
+    pub scrolling_region: bool,
+
+    /// Emit tabstop positions by clearing all tabs (CSI 3 g) and setting
+    /// each configured tabstop with HTS.
+    pub tabstops: bool,
+
+    /// Emit the present working directory using OSC 7.
+    pub pwd: bool,
+
+    /// Emit keyboard modes such as ModifyOtherKeys using CSI > 4 m
+    /// sequences.
+    pub keyboard: bool,
+
+    /// The screen extras to emit. TerminalFormatter always only
+    /// emits data for the currently active screen. If you want to emit
+    /// data for all screens, you should manually construct a no-content
+    /// terminal formatter, followed by screen formatters.
+    pub screen: ScreenExtra,
+}
+
+impl TerminalExtra {
+    /// Emit nothing.
+    pub const NONE: TerminalExtra = TerminalExtra {
+        palette: false,
+        modes: false,
+        scrolling_region: false,
+        tabstops: false,
+        pwd: false,
+        keyboard: false,
+        screen: ScreenExtra::NONE,
+    };
+
+    /// Emit style-relevant information only such as palettes.
+    pub const STYLES: TerminalExtra = TerminalExtra {
+        palette: true,
+        modes: false,
+        scrolling_region: false,
+        tabstops: false,
+        pwd: false,
+        keyboard: false,
+        screen: ScreenExtra::STYLES,
+    };
+
+    /// Emit everything. This reconstructs the terminal state as closely
+    /// as possible.
+    pub const ALL: TerminalExtra = TerminalExtra {
+        palette: true,
+        modes: true,
+        scrolling_region: true,
+        tabstops: true,
+        pwd: true,
+        keyboard: true,
+        screen: ScreenExtra::ALL,
+    };
+}
+
+impl<'a> TerminalFormatter<'a> {
+    pub fn new(terminal: &'a Terminal, opts: Options) -> Self {
+        TerminalFormatter {
+            terminal,
+            opts,
+            content: Content::Selection(None),
+            extra: TerminalExtra::STYLES,
+            pin_map: None,
+        }
+    }
+
+    /// Format into a new `String` (convenience, no pin map is touched
+    /// beyond what `pin_map` asks for).
+    pub fn format_string(self) -> Result<String> {
+        let mut buf = Vec::new();
+        self.format(&mut buf)?;
+        String::from_utf8(buf).map_err(|_| invalid_cp())
+    }
+
+    pub fn format(mut self, writer: &mut dyn Write) -> Result<()> {
+        let pages = &self.terminal.screens.active().pages;
+
+        // Emit palette before screen content if using VT format. Technically
+        // we could do this after but this way if replay is slow for whatever
+        // reason the colors will be right right away.
+        if self.extra.palette {
+            let mut buf: Vec<u8> = Vec::new();
+            match self.opts.emit {
+                Format::Plain => {}
+
+                Format::Vt => {
+                    for (i, rgb) in self.terminal.colors.palette.current.iter().enumerate() {
+                        write!(
+                            buf,
+                            "\x1b]4;{};rgb:{:02x}/{:02x}/{:02x}\x1b\\",
+                            i, rgb.r, rgb.g, rgb.b
+                        )?;
+                    }
+                }
+
+                // For HTML, we emit CSS to setup our palette variables.
+                Format::Html => {
+                    buf.extend_from_slice(b"<style>:root{");
+                    for (i, rgb) in self.terminal.colors.palette.current.iter().enumerate() {
+                        write!(
+                            buf,
+                            "--vt-palette-{}: #{:02x}{:02x}{:02x};",
+                            i, rgb.r, rgb.g, rgb.b
+                        )?;
+                    }
+                    buf.extend_from_slice(b"}</style>");
+                }
+            }
+            writer.write_all(&buf)?;
+
+            // If we have a pin_map, add the bytes we wrote to map. Map all
+            // those bytes to the same pin. Use the top left to ensure the
+            // node is always properly initialized.
+            if self.opts.emit != Format::Plain
+                && let Some(m) = self.pin_map.as_deref_mut()
+            {
+                let top = pages.get_top_left(Tag::Screen).expect("top left");
+                m.extend(std::iter::repeat_n(top, buf.len()));
+            }
+        }
+
+        // Emit terminal modes that differ from defaults. We probably have
+        // some modes we want to emit before and some after, but for now for
+        // simplicity we just emit them all before. If we make this more complex
+        // later we should add test cases for it.
+        if self.opts.emit == Format::Vt && self.extra.modes {
+            let mut buf: Vec<u8> = Vec::new();
+            for entry in ENTRIES {
+                let current = self.terminal.modes.get(entry.mode);
+                let default_val = self.terminal.modes.default.get(entry.mode);
+
+                if current != default_val {
+                    let prefix = if entry.ansi { "" } else { "?" };
+                    let suffix = if current { "h" } else { "l" };
+                    write!(buf, "\x1b[{}{}{}", prefix, entry.value, suffix)?;
+                }
+            }
+            writer.write_all(&buf)?;
+
+            if let Some(m) = self.pin_map.as_deref_mut() {
+                let top = pages.get_top_left(Tag::Screen).expect("top left");
+                m.extend(std::iter::repeat_n(top, buf.len()));
+            }
+        }
+
+        let mut screen_formatter =
+            ScreenFormatter::new(self.terminal.screens.active(), self.opts.clone());
+        screen_formatter.content = self.content;
+        screen_formatter.extra = self.extra.screen;
+        screen_formatter.pin_map = self.pin_map.as_deref_mut();
+        screen_formatter.format(writer)?;
+
+        // Extra terminal state to emit after the screen contents so that
+        // it doesn't impact the emitted contents.
+        if self.opts.emit == Format::Vt {
+            let mut buf: Vec<u8> = Vec::new();
+
+            // Emit scrolling region using DECSTBM and DECSLRM
+            if self.extra.scrolling_region {
+                let region = &self.terminal.scrolling_region;
+
+                // DECSTBM: top and bottom margins (1-indexed)
+                // Only emit if not the full screen
+                if region.top != 0 || region.bottom != self.terminal.rows - 1 {
+                    write!(buf, "\x1b[{};{}r", region.top + 1, region.bottom + 1)?;
+                }
+
+                // DECSLRM: left and right margins (1-indexed)
+                // Only emit if not the full width
+                if region.left != 0 || region.right != self.terminal.cols - 1 {
+                    write!(buf, "\x1b[{};{}s", region.left + 1, region.right + 1)?;
+                }
+            }
+
+            // Emit tabstop positions
+            if self.extra.tabstops {
+                // Clear all tabs (CSI 3 g)
+                write!(buf, "\x1b[3g")?;
+
+                // Set each configured tabstop by moving cursor and using HTS
+                for col in 0..usize::from(self.terminal.cols) {
+                    if self.terminal.tabstops.get(col) {
+                        // Move cursor to the column (1-indexed)
+                        write!(buf, "\x1b[{}G", col + 1)?;
+                        // Set tab (HTS)
+                        write!(buf, "\x1bH")?;
+                    }
+                }
+            }
+
+            // Emit keyboard modes such as ModifyOtherKeys
+            if self.extra.keyboard {
+                // Only emit if modify_other_keys_2 is true
+                if self.terminal.flags.modify_other_keys_2 {
+                    write!(buf, "\x1b[>4;2m")?;
+                }
+            }
+
+            // Emit present working directory using OSC 7
+            if self.extra.pwd {
+                let pwd = &self.terminal.pwd;
+                if !pwd.is_empty() {
+                    buf.extend_from_slice(b"\x1b]7;");
+                    buf.extend_from_slice(pwd);
+                    buf.extend_from_slice(b"\x1b\\");
+                }
+            }
+
+            writer.write_all(&buf)?;
+
+            // If we have a pin_map, add the bytes we wrote to map.
+            if let Some(m) = self.pin_map.as_deref_mut() {
+                map_pad_last_or_top(m, pages, buf.len());
+            }
+        }
+        Ok(())
+    }
+}
+
+/// Screen formatter formats a single terminal screen (e.g. primary vs alt).
+pub struct ScreenFormatter<'a> {
+    /// The screen to format.
+    pub screen: &'a Screen,
+
+    /// The common options
+    pub opts: Options,
+
+    /// The content to include.
+    pub content: Content,
+
+    /// Extra stuff to emit, such as cursor, style, hyperlinks, etc.
+    /// This information is ONLY emitted when the format is "vt".
+    pub extra: ScreenExtra,
+
+    /// If non-null, then `map` will contain the Pin of every byte
+    /// byte written to the writer offset by the byte index.
+    ///
+    /// Note that some emitted bytes may not correspond to any Pin, such as
+    /// the extra data around screen state. For these, we'll map it to the
+    /// most previous pin so there is some continuity but its an arbitrary
+    /// choice.
+    ///
+    /// Warning: there is a significant performance hit to track this
+    pub pin_map: Option<PinMap<'a>>,
+}
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum Content {
+    /// Emit no content, only terminal state such as modes, palette, etc.
+    /// via extra.
+    None,
+
+    /// Emit the content specified by the selection. None for all.
+    /// The selection is inclusive on both ends.
+    Selection(Option<Selection>),
+}
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub struct ScreenExtra {
+    /// Emit cursor position using CUP (CSI H).
+    pub cursor: bool,
+
+    /// Emit current SGR style state based on the cursor's active style_id.
+    /// This reconstructs the SGR attributes (bold, italic, colors, etc.) at
+    /// the cursor position.
+    pub style: bool,
+
+    /// Emit current hyperlink state using OSC 8 sequences.
+    /// This sets the active hyperlink based on cursor.hyperlink_id.
+    pub hyperlink: bool,
+
+    /// Emit character protection mode using DECSCA.
+    pub protection: bool,
+
+    /// Emit Kitty keyboard protocol state using CSI > u and CSI = sequences.
+    pub kitty_keyboard: bool,
+
+    /// Emit character set designations and invocations.
+    /// This includes G0-G3 designations (ESC ( ) * +) and GL/GR invocations.
+    pub charsets: bool,
+}
+
+impl ScreenExtra {
+    /// Emit nothing.
+    pub const NONE: ScreenExtra = ScreenExtra {
+        cursor: false,
+        style: false,
+        hyperlink: false,
+        protection: false,
+        kitty_keyboard: false,
+        charsets: false,
+    };
+
+    /// Emit style-relevant information only.
+    pub const STYLES: ScreenExtra = ScreenExtra {
+        cursor: false,
+        style: true,
+        hyperlink: true,
+        protection: false,
+        kitty_keyboard: false,
+        charsets: false,
+    };
+
+    /// Emit everything. This reconstructs the screen state as closely
+    /// as possible.
+    pub const ALL: ScreenExtra = ScreenExtra {
+        cursor: true,
+        style: true,
+        hyperlink: true,
+        protection: true,
+        kitty_keyboard: true,
+        charsets: true,
+    };
+
+    fn is_set(self) -> bool {
+        self != Self::NONE
+    }
+}
+
+impl<'a> ScreenFormatter<'a> {
+    pub fn new(screen: &'a Screen, opts: Options) -> Self {
+        ScreenFormatter {
+            screen,
+            opts,
+            content: Content::Selection(None),
+            extra: ScreenExtra::NONE,
+            pin_map: None,
+        }
+    }
+
+    /// Format into a new `String`.
+    pub fn format_string(self) -> Result<String> {
+        let mut buf = Vec::new();
+        self.format(&mut buf)?;
+        String::from_utf8(buf).map_err(|_| invalid_cp())
+    }
+
+    pub fn format(mut self, writer: &mut dyn Write) -> Result<()> {
+        match self.content {
+            Content::None => {}
+
+            Content::Selection(selection) => {
+                // Emit our pagelist contents according to our selection.
+                let mut list_formatter =
+                    PageListFormatter::new(&self.screen.pages, self.opts.clone());
+                list_formatter.pin_map = self.pin_map.as_deref_mut();
+                if let Some(sel) = selection {
+                    list_formatter.top_left = Some(sel.top_left(&self.screen.pages));
+                    list_formatter.bottom_right = Some(sel.bottom_right(&self.screen.pages));
+                    list_formatter.rectangle = sel.rectangle;
+                }
+                list_formatter.format(writer)?;
+            }
+        }
+
+        // Emit extra screen state after content if we care. The state has
+        // to be emitted after since some state such as cursor position and
+        // style are impacted by content rendering.
+        match self.opts.emit {
+            Format::Plain => return Ok(()),
+            Format::Vt => {
+                if !self.extra.is_set() {
+                    return Ok(());
+                }
+            }
+
+            // HTML doesn't preserve any screen state because it has
+            // nothing to do with rendering.
+            Format::Html => return Ok(()),
+        }
+
+        let mut buf: Vec<u8> = Vec::new();
+
+        // Emit current SGR style state
+        if self.extra.style {
+            let cursor = &self.screen.cursor;
+            write!(buf, "{}", cursor.style.formatter_vt())?;
+        }
+
+        // Emit current hyperlink state using OSC 8
+        if self.extra.hyperlink
+            && let Some(link) = &self.screen.cursor.hyperlink
+        {
+            // Start hyperlink with uri (and explicit id if present)
+            match &link.id {
+                HyperlinkId::Explicit(id) => {
+                    buf.extend_from_slice(b"\x1b]8;id=");
+                    buf.extend_from_slice(id);
+                    buf.push(b';');
+                    buf.extend_from_slice(&link.uri);
+                    buf.extend_from_slice(b"\x1b\\");
+                }
+                HyperlinkId::Implicit(_) => {
+                    buf.extend_from_slice(b"\x1b]8;;");
+                    buf.extend_from_slice(&link.uri);
+                    buf.extend_from_slice(b"\x1b\\");
+                }
+            }
+        }
+
+        // Emit character protection mode using DECSCA
+        if self.extra.protection && self.screen.cursor.protected {
+            // DEC protected mode
+            write!(buf, "\x1b[1\"q")?;
+        }
+
+        // Emit Kitty keyboard protocol state using CSI = u
+        if self.extra.kitty_keyboard {
+            let current_flags = self.screen.kitty_keyboard.current();
+            if current_flags.int() != ghostty_vt::kitty::key::Flags::DISABLED.int() {
+                write!(buf, "\x1b[={};1u", current_flags.int())?;
+            }
+        }
+
+        // Emit character set designations and invocations
+        if self.extra.charsets {
+            let charset = &self.screen.charset;
+
+            // Emit G0-G3 designations
+            for slot in [Slots::G0, Slots::G1, Slots::G2, Slots::G3] {
+                let cs = charset.charsets.get(slot);
+                if cs != Charset::Utf8 {
+                    // Only emit non-default charsets
+                    let intermediate = match slot {
+                        Slots::G0 => '(',
+                        Slots::G1 => ')',
+                        Slots::G2 => '*',
+                        Slots::G3 => '+',
+                    };
+                    let fin = match cs {
+                        Charset::Ascii => 'B',
+                        Charset::British => 'A',
+                        Charset::DecSpecial => '0',
+                        Charset::Utf8 => continue,
+                    };
+                    write!(buf, "\x1b{intermediate}{fin}")?;
+                }
+            }
+
+            // Emit GL invocation if not G0
+            if charset.gl != Slots::G0 {
+                let seq: &[u8] = match charset.gl {
+                    Slots::G0 => unreachable!(),
+                    Slots::G1 => b"\x0e",  // SO - Shift Out
+                    Slots::G2 => b"\x1bn", // LS2
+                    Slots::G3 => b"\x1bo", // LS3
+                };
+                buf.extend_from_slice(seq);
+            }
+
+            // Emit GR invocation if not G2
+            if charset.gr != Slots::G2 {
+                let seq: &[u8] = match charset.gr {
+                    Slots::G0 => unreachable!(), // GR can't be G0
+                    Slots::G1 => b"\x1b~",       // LS1R
+                    Slots::G2 => unreachable!(),
+                    Slots::G3 => b"\x1b|", // LS3R
+                };
+                buf.extend_from_slice(seq);
+            }
+        }
+
+        // Emit cursor position using CUP (CSI H)
+        if self.extra.cursor {
+            let cursor = &self.screen.cursor;
+            // CUP is 1-indexed
+            write!(buf, "\x1b[{};{}H", cursor.y + 1, cursor.x + 1)?;
+        }
+
+        writer.write_all(&buf)?;
+
+        // If we have a pin_map, map all the extra bytes to the same pin.
+        if let Some(m) = self.pin_map.as_deref_mut() {
+            map_pad_last_or_top(m, &self.screen.pages, buf.len());
+        }
+        Ok(())
+    }
+}
+
+/// PageList formatter formats multiple pages as represented by a PageList.
+pub struct PageListFormatter<'a> {
+    /// The pagelist to format.
+    pub list: &'a PageList,
+
+    /// The common options
+    pub opts: Options,
+
+    /// The bounds of the PageList to format. The top left and bottom right
+    /// MUST be ordered properly.
+    pub top_left: Option<Pin>,
+    pub bottom_right: Option<Pin>,
+
+    /// If true, the boundaries define a rectangle selection where start_x
+    /// and end_x apply to every row, not just the first and last.
+    pub rectangle: bool,
+
+    /// If non-null, then `map` will contain the Pin of every byte
+    /// byte written to the writer offset by the byte index.
+    ///
+    /// Warning: there is a significant performance hit to track this
+    pub pin_map: Option<PinMap<'a>>,
+}
+
+impl<'a> PageListFormatter<'a> {
+    pub fn new(list: &'a PageList, opts: Options) -> Self {
+        PageListFormatter {
+            list,
+            opts,
+            top_left: None,
+            bottom_right: None,
+            rectangle: false,
+            pin_map: None,
+        }
+    }
+
+    /// Format into a new `String`.
+    pub fn format_string(self) -> Result<String> {
+        let mut buf = Vec::new();
+        self.format(&mut buf)?;
+        String::from_utf8(buf).map_err(|_| invalid_cp())
+    }
+
+    pub fn format(mut self, writer: &mut dyn Write) -> Result<()> {
+        let tl = self
+            .top_left
+            .unwrap_or_else(|| self.list.get_top_left(Tag::Screen).expect("top left"));
+        let br = self.bottom_right.unwrap_or_else(|| {
+            self.list
+                .get_bottom_right(Tag::Screen)
+                .expect("bottom right")
+        });
+
+        // If we keep track of pins, we'll need this.
+        let mut point_map: Vec<Coordinate> = Vec::new();
+
+        let mut page_state: Option<TrailingState> = None;
+        for chunk in pin_page_iterator(self.list, tl, br) {
+            assert!(chunk.start < chunk.end);
+            assert!(chunk.end > 0);
+
+            let node = self.list.node(chunk.node).expect("chunk node");
+            let mut formatter = PageFormatter::new(&node.data, &self.opts);
+            formatter.start_y = chunk.start;
+            formatter.end_y = Some(chunk.end - 1);
+            formatter.trailing_state = page_state;
+            formatter.rectangle = self.rectangle;
+
+            // For rectangle selection, apply start_x and end_x to all chunks
+            if self.rectangle {
+                formatter.start_x = tl.x;
+                formatter.end_x = Some(br.x);
+            } else {
+                // Otherwise only on the first/last, respectively.
+                if chunk.node == tl.node {
+                    formatter.start_x = tl.x;
+                }
+                if chunk.node == br.node {
+                    formatter.end_x = Some(br.x);
+                }
+            }
+
+            // If we're tracking pins, then we setup a point map for the
+            // page formatter (cause it can't track pins). And then we convert
+            // this to pins later.
+            let tracking = self.pin_map.is_some();
+            if tracking {
+                point_map.clear();
+                formatter.point_map = Some(&mut point_map);
+            }
+
+            page_state = Some(formatter.format_with_state(writer)?);
+
+            // If we're tracking pins then grab our points and write them
+            // to our pin map.
+            if let Some(m) = self.pin_map.as_deref_mut() {
+                for coord in &point_map {
+                    m.push(Pin {
+                        node: chunk.node,
+                        x: coord.x,
+                        y: coord.y as size::CellCountInt,
+                        garbage: false,
+                    });
+                }
+            }
+        }
+        Ok(())
+    }
+}
+
+/// Trailing state. This is used to ensure that rows wrapped across
+/// multiple pages are unwrapped properly, as well as other accounting
+/// we may do in the future.
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Default)]
+pub struct TrailingState {
+    pub rows: usize,
+    pub cells: usize,
+}
+
+impl TrailingState {
+    pub const EMPTY: TrailingState = TrailingState { rows: 0, cells: 0 };
+}
+
+/// Page formatter.
+///
+/// For styled formatting such as VT, this will emit references for palette
+/// colors. If you want to capture the palette as-is at the type of formatting,
+/// you'll have to emit the sequences for setting up the palette prior to
+/// this formatting. (TODO: A function to do this)
+pub struct PageFormatter<'a> {
+    /// The page to format.
+    pub page: &'a Page,
+
+    /// The common options
+    pub opts: &'a Options,
+
+    /// Start and end points within the page to format. If end x is not given
+    /// then it will be the full width. If end y is not given then it will be
+    /// the full height.
+    ///
+    /// The start and end are both inclusive, so equal values will still
+    /// return a non-empty result (i.e. a single cell or row).
+    ///
+    /// The start x is considered the X in the first row and end X is
+    /// X in the final row. This isn't a rectangle selection by default.
+    ///
+    /// If start X falls on the second column of a wide character, then
+    /// the entire character will be included (as if you specified the
+    /// previous column).
+    pub start_x: size::CellCountInt,
+    pub start_y: size::CellCountInt,
+    pub end_x: Option<size::CellCountInt>,
+    pub end_y: Option<size::CellCountInt>,
+
+    /// If true, the start x/y and end x/y define a rectangle selection.
+    /// In this case, the boundaries will apply to every row, not just
+    /// the first and last.
+    pub rectangle: bool,
+
+    /// If non-null, then `map` will contain the x/y coordinate of every
+    /// byte written to the writer offset by the byte index.
+    ///
+    /// The x/y coordinate will be the coordinates within the page.
+    ///
+    /// Warning: there is a significant performance hit to track this
+    pub point_map: Option<&'a mut Vec<Coordinate>>,
+
+    /// The previous trailing state from the prior page. If you're iterating
+    /// over multiple pages this helps ensure that unwrapping and other
+    /// accounting works properly.
+    pub trailing_state: Option<TrailingState>,
+}
+
+impl<'a> PageFormatter<'a> {
+    /// Initializes a page formatter. Other options can be set directly on the
+    /// struct after initialization and before calling `format()`.
+    pub fn new(page: &'a Page, opts: &'a Options) -> Self {
+        PageFormatter {
+            page,
+            opts,
+            start_x: 0,
+            start_y: 0,
+            end_x: None,
+            end_y: None,
+            rectangle: false,
+            point_map: None,
+            trailing_state: None,
+        }
+    }
+
+    /// Format into a new `String`.
+    pub fn format_string(self) -> Result<String> {
+        let mut buf = Vec::new();
+        self.format(&mut buf)?;
+        String::from_utf8(buf).map_err(|_| invalid_cp())
+    }
+
+    pub fn format(self, writer: &mut dyn Write) -> Result<()> {
+        self.format_with_state(writer).map(|_| ())
+    }
+
+    fn map_push_n(&mut self, coord: Coordinate, n: usize) {
+        if let Some(m) = self.point_map.as_deref_mut() {
+            m.extend(std::iter::repeat_n(coord, n));
+        }
+    }
+
+    pub fn format_with_state(mut self, writer: &mut dyn Write) -> Result<TrailingState> {
+        let page = self.page;
+        let opts = self.opts;
+        let mut blank_rows: usize = 0;
+        let mut blank_cells: usize = 0;
+
+        // Continue our prior trailing state if we have it, but only if we're
+        // starting from the beginning (start_y and start_x are both 0).
+        // If a non-zero start position is specified, ignore trailing state.
+        if let Some(state) = self.trailing_state
+            && self.start_y == 0
+            && self.start_x == 0
+        {
+            blank_rows = state.rows;
+            blank_cells = state.cells;
+        }
+        let ret = |rows: usize, cells: usize| TrailingState { rows, cells };
+
+        // Setup our starting column and perform some validation for overflows.
+        // Note: start_x only applies to the first row, end_x only applies to the last row.
+        let start_x = self.start_x;
+        if start_x >= page.size.cols {
+            return Ok(ret(blank_rows, blank_cells));
+        }
+        let end_x_unclamped = self.end_x.unwrap_or(page.size.cols - 1);
+        let mut end_x = end_x_unclamped.min(page.size.cols - 1);
+
+        // Setup our starting row and perform some validation for overflows.
+        let start_y = self.start_y;
+        if start_y >= page.size.rows {
+            return Ok(ret(blank_rows, blank_cells));
+        }
+        let end_y_unclamped = self.end_y.unwrap_or(page.size.rows - 1);
+        if start_y > end_y_unclamped {
+            return Ok(ret(blank_rows, blank_cells));
+        }
+        let mut end_y = end_y_unclamped.min(page.size.rows - 1);
+
+        // Edge case: if our end x/y falls on a spacer head AND we're unwrapping,
+        // then we move the x/y to the start of the next row (if available).
+        if opts.unwrap && !self.rectangle {
+            let cells = page.get_cells(usize::from(end_y)).expect("row cells");
+            if cells[usize::from(end_x)].wide() == Wide::SpacerHead {
+                // Move to next row if available
+                //
+                // TODO: if unavailable, we should add to our trailing state
+                //
+                // so the pagelist formatter can be aware and maybe add
+                // another page
+                if end_y < page.size.rows - 1 {
+                    end_y += 1;
+                    end_x = 0;
+                }
+            }
+        }
+
+        // If we only have a single row, validate that start_x <= end_x
+        if start_y == end_y && start_x > end_x {
+            return Ok(ret(blank_rows, blank_cells));
+        }
+
+        // Wrap HTML output in monospace font styling
+        match opts.emit {
+            Format::Plain => {}
+
+            Format::Html => {
+                let mut header: Vec<u8> = Vec::new();
+
+                // Monospace and whitespace preserving
+                header.extend_from_slice(b"<div style=\"font-family: monospace; white-space: pre;");
+
+                // Background/foreground colors
+                if let Some(bg) = opts.background {
+                    write!(header, "background-color: #{};", hex(bg))?;
+                }
+                if let Some(fg) = opts.foreground {
+                    write!(header, "color: #{};", hex(fg))?;
+                }
+
+                header.extend_from_slice(b"\">");
+
+                writer.write_all(&header)?;
+                self.map_push_n(Coordinate { x: 0, y: 0 }, header.len());
+            }
+
+            Format::Vt => {
+                // OSC 10 sets foreground color, OSC 11 sets background color
+                let mut header: Vec<u8> = Vec::new();
+                if let Some(fg) = opts.foreground {
+                    write!(
+                        header,
+                        "\x1b]10;rgb:{:02x}/{:02x}/{:02x}\x1b\\",
+                        fg.r, fg.g, fg.b
+                    )?;
+                }
+                if let Some(bg) = opts.background {
+                    write!(
+                        header,
+                        "\x1b]11;rgb:{:02x}/{:02x}/{:02x}\x1b\\",
+                        bg.r, bg.g, bg.b
+                    )?;
+                }
+
+                writer.write_all(&header)?;
+                self.map_push_n(Coordinate { x: 0, y: 0 }, header.len());
+            }
+        }
+
+        // Our style for non-plain formats
+        let mut style = Style::default();
+
+        // Track hyperlink state for HTML output. We need to close </a> tags
+        // when the hyperlink changes or ends.
+        let mut current_hyperlink_id: Option<u16> = None;
+
+        let mut scratch: Vec<u8> = Vec::new();
+
+        'rows: for y in start_y..=end_y {
+            let row = *page.get_row(usize::from(y)).expect("row");
+            let cells: &[Cell] = page.get_cells(usize::from(y)).expect("cells");
+
+            // Determine the x range for this row
+            // - First row: start_x to end of row (or end_x if single row)
+            // - Last row: start of row to end_x
+            // - Middle rows: full width
+            let (cells_subset, row_start_x) = {
+                // The end is always straightforward
+                let row_end_x: size::CellCountInt = if self.rectangle || y == end_y {
+                    end_x + 1
+                } else {
+                    page.size.cols
+                };
+
+                // The first we have to check if our start X falls on the
+                // tail of a wide character.
+                let row_start_x: size::CellCountInt =
+                    if start_x > 0 && (self.rectangle || y == start_y) {
+                        match cells[usize::from(start_x)].wide() {
+                            // Include the prior cell to get the full wide char
+                            Wide::SpacerTail => start_x - 1,
+
+                            // If we're a spacer head on our first row then we
+                            // skip this whole row.
+                            Wide::SpacerHead => continue 'rows,
+
+                            Wide::Narrow | Wide::Wide => start_x,
+                        }
+                    } else {
+                        0
+                    };
+
+                (
+                    &cells[usize::from(row_start_x)..usize::from(row_end_x)],
+                    row_start_x,
+                )
+            };
+
+            // If this row is blank, accumulate to avoid a bunch of extra
+            // work later. If it isn't blank, make sure we dump all our
+            // blanks.
+            if !Cell::has_text_any(cells_subset) {
+                blank_rows += 1;
+                continue;
+            }
+
+            if blank_rows > 0 {
+                // Reset style before emitting newlines to prevent background
+                // colors from bleeding into the next line's leading cells.
+                if !style.is_default() {
+                    self.format_style_close(writer)?;
+                    style = Style::default();
+                }
+
+                let sequence: &[u8] = match opts.emit {
+                    // Plaintext just uses standard newlines because newlines
+                    // on their own usually move the cursor back in anywhere
+                    // you type plaintext.
+                    Format::Plain => b"\n",
+
+                    // VT uses \r\n because in a raw pty, \n alone doesn't
+                    // guarantee moving the cursor back to column 0. \r
+                    // makes it work for sure.
+                    Format::Vt => b"\r\n",
+
+                    // HTML uses just \n because HTML rendering will move
+                    // the cursor back.
+                    Format::Html => b"\n",
+                };
+
+                for _ in 0..blank_rows {
+                    writer.write_all(sequence)?;
+                }
+
+                // \r and \n map to the row that ends with this newline.
+                // If we're continuing (trailing state) then this will be
+                // in a prior page, so we just map to the first row of this
+                // page.
+                if let Some(map) = self.point_map.as_deref_mut() {
+                    let start = map.last().copied().unwrap_or(Coordinate { x: 0, y: 0 });
+
+                    // The first one inherits the x value.
+                    map.extend(std::iter::repeat_n(
+                        Coordinate {
+                            x: start.x,
+                            y: start.y,
+                        },
+                        sequence.len(),
+                    ));
+
+                    // All others have x = 0 since they reference their prior
+                    // blank line.
+                    for y_offset in 1..blank_rows {
+                        map.extend(std::iter::repeat_n(
+                            Coordinate {
+                                x: 0,
+                                y: start.y + y_offset as u32,
+                            },
+                            sequence.len(),
+                        ));
+                    }
+                }
+
+                blank_rows = 0;
+            }
+
+            // If we're not wrapped, we always add a newline so after
+            // the row is printed we can add a newline.
+            if !row.wrap() || !opts.unwrap {
+                blank_rows += 1;
+            }
+
+            // If the row doesn't continue a wrap then we need to reset
+            // our blank cell count.
+            if !row.wrap_continuation() || !opts.unwrap {
+                blank_cells = 0;
+            }
+
+            // Go through each cell and print it
+            'cells: for (i, cell) in cells_subset.iter().enumerate() {
+                let x: size::CellCountInt = row_start_x + i as size::CellCountInt;
+
+                // Skip spacers. These happen naturally when wide characters
+                // are printed again on the screen (for well-behaved terminals!)
+                match cell.wide() {
+                    Wide::Narrow | Wide::Wide => {}
+                    Wide::SpacerHead | Wide::SpacerTail => continue,
+                }
+
+                // If we have a zero value, then we accumulate a counter. We
+                // only want to turn zero values into spaces if we have a non-zero
+                // char sometime later.
+                'blank: {
+                    // If we're emitting styled output (not plaintext) and
+                    // the cell has some kind of styling or is not empty
+                    // then this isn't blank.
+                    if opts.emit.styled() && (!cell.is_empty() || cell.has_styling()) {
+                        break 'blank;
+                    }
+
+                    // Cells with no text are blank
+                    if !cell.has_text() {
+                        blank_cells += 1;
+                        continue 'cells;
+                    }
+
+                    // Trailing spaces are blank. We know it is trailing
+                    // because if we get a non-empty cell later we'll
+                    // fill the blanks.
+                    if cell.codepoint() == ' ' as u32 && opts.trim {
+                        blank_cells += 1;
+                        continue 'cells;
+                    }
+                }
+
+                // This cell is not blank. If we have accumulated blank cells
+                // then we want to emit them now.
+                if blank_cells > 0 {
+                    scratch.clear();
+                    scratch.resize(blank_cells, b' ');
+                    writer.write_all(&scratch)?;
+
+                    if let Some(map) = self.point_map.as_deref_mut() {
+                        // Map each blank cell to its coordinate. Blank cells can span
+                        // multiple rows if they carry over from wrap continuation.
+                        let mut remaining_blanks = blank_cells;
+                        let mut blank_x = x;
+                        let mut blank_y = y;
+                        while remaining_blanks > 0 {
+                            if blank_x > 0 {
+                                // We have space in this row
+                                blank_x -= 1;
+                            } else if blank_y > 0 {
+                                // Wrap to previous row
+                                blank_y -= 1;
+                                blank_x = page.size.cols - 1;
+                            } else {
+                                // Can't go back further, just use (0, 0)
+                                blank_x = 0;
+                                blank_y = 0;
+                            }
+
+                            map.push(Coordinate {
+                                x: blank_x,
+                                y: u32::from(blank_y),
+                            });
+                            remaining_blanks -= 1;
+                        }
+                    }
+
+                    blank_cells = 0;
+                }
+
+                'style: {
+                    // If we aren't emitting styled output then we don't
+                    // have to worry about styles.
+                    if !opts.emit.styled() {
+                        break 'style;
+                    }
+
+                    // Get our cell style.
+                    let cell_style = self.cell_style(*cell);
+
+                    // If the style hasn't changed, don't bloat output.
+                    if cell_style.eql(style) {
+                        break 'style;
+                    }
+
+                    // If we had a previous style, we need to close it,
+                    // because we've confirmed we have some new style
+                    // (which is maybe default).
+                    if !style.is_default() {
+                        match opts.emit {
+                            Format::Html => self.format_style_close(writer)?,
+
+                            // For VT, we only close if we're switching to a default
+                            // style because any non-default style will emit
+                            // a \x1b[0m as the start of a VT coloring sequence.
+                            Format::Vt => {
+                                if cell_style.is_default() {
+                                    self.format_style_close(writer)?;
+                                }
+                            }
+
+                            // Unreachable because of the styled() check at the
+                            // top of this block.
+                            Format::Plain => unreachable!(),
+                        }
+                    }
+
+                    // At this point, we can copy our style over
+                    style = cell_style;
+
+                    // If we're just the default style now, we're done.
+                    if cell_style.is_default() {
+                        break 'style;
+                    }
+
+                    // New style, emit it.
+                    scratch.clear();
+                    self.format_style_open(&mut scratch, &style)?;
+                    writer.write_all(&scratch)?;
+
+                    // If we have a point map, we map the style to
+                    // this cell.
+                    self.map_push_n(Coordinate { x, y: u32::from(y) }, scratch.len());
+                }
+
+                // Hyperlink state
+                'hyperlink: {
+                    // We currently only emit hyperlinks for HTML. In the
+                    // future we can support emitting OSC 8 hyperlinks for
+                    // VT output as well.
+                    if opts.emit != Format::Html {
+                        break 'hyperlink;
+                    }
+
+                    // Get the hyperlink ID. This ID is our internal ID,
+                    // not necessarily the OSC8 ID.
+                    let link_id_: Option<u16> = if cell.hyperlink() {
+                        page.cell_index(usize::from(x), usize::from(y))
+                            .ok()
+                            .and_then(|i| page.lookup_hyperlink(i))
+                    } else {
+                        None
+                    };
+
+                    // If our hyperlink IDs match (even null) then we have
+                    // identical hyperlink state and we do nothing.
+                    if current_hyperlink_id == link_id_ {
+                        break 'hyperlink;
+                    }
+
+                    // If our prior hyperlink ID was non-null, we need to
+                    // close it because the ID has changed.
+                    if current_hyperlink_id.is_some() {
+                        self.format_hyperlink_close(writer)?;
+                        current_hyperlink_id = None;
+                    }
+
+                    // Set our current hyperlink ID
+                    let Some(link_id) = link_id_ else {
+                        break 'hyperlink;
+                    };
+                    current_hyperlink_id = Some(link_id);
+
+                    // Emit the opening hyperlink tag
+                    let uri: Vec<u8> = page
+                        .hyperlink_set
+                        .get(link_id)
+                        .map(|l| l.uri.clone())
+                        .unwrap_or_default();
+                    scratch.clear();
+                    self.format_hyperlink_open(&mut scratch, &uri)?;
+                    writer.write_all(&scratch)?;
+
+                    // If we have a point map, we map the hyperlink to
+                    // this cell.
+                    self.map_push_n(Coordinate { x, y: u32::from(y) }, scratch.len());
+                }
+
+                match cell.content_tag() {
+                    // We combine codepoint and graphemes because both have
+                    // shared style handling.
+                    ContentTag::Codepoint | ContentTag::CodepointGrapheme => {
+                        scratch.clear();
+                        self.write_cell(&mut scratch, *cell, x, y)?;
+                        writer.write_all(&scratch)?;
+
+                        // If we have a point map, all codepoints map to this
+                        // cell.
+                        self.map_push_n(Coordinate { x, y: u32::from(y) }, scratch.len());
+                    }
+
+                    // Cells with only background color (no text). Emit a space
+                    // with the appropriate background color SGR sequence.
+                    ContentTag::BgColorPalette | ContentTag::BgColorRgb => {
+                        writer.write_all(b" ")?;
+                        self.map_push_n(Coordinate { x, y: u32::from(y) }, 1);
+                    }
+                }
+            }
+        }
+
+        // If the style is non-default, we need to close our style tag.
+        if !style.is_default() {
+            self.format_style_close(writer)?;
+        }
+
+        // Close any open hyperlink for HTML output
+        if current_hyperlink_id.is_some() {
+            self.format_hyperlink_close(writer)?;
+        }
+
+        // Close the monospace wrapper for HTML output
+        if opts.emit == Format::Html {
+            let closing = b"</div>";
+            writer.write_all(closing)?;
+            if let Some(map) = self.point_map.as_deref_mut() {
+                let last = map.last().copied().unwrap_or(Coordinate { x: 0, y: 0 });
+                map.extend(std::iter::repeat_n(last, closing.len()));
+            }
+        }
+
+        Ok(ret(blank_rows, blank_cells))
+    }
+
+    fn write_cell(
+        &self,
+        out: &mut Vec<u8>,
+        cell: Cell,
+        x: size::CellCountInt,
+        y: size::CellCountInt,
+    ) -> Result<()> {
+        // Blank cells get an empty space that isn't replaced by anything
+        // because it isn't really a space. We do this so that formatting
+        // is preserved if we're emitting styles.
+        if !cell.has_text() {
+            out.push(b' ');
+            return Ok(());
+        }
+
+        self.write_codepoint_with_replacement(out, cell.codepoint())?;
+        if cell.content_tag() == ContentTag::CodepointGrapheme {
+            let idx = self
+                .page
+                .cell_index(usize::from(x), usize::from(y))
+                .map_err(|_| invalid_cp())?;
+            for &cp in self.page.lookup_grapheme(idx).expect("grapheme") {
+                self.write_codepoint_with_replacement(out, cp)?;
+            }
+        }
+        Ok(())
+    }
+
+    fn write_codepoint_with_replacement(&self, out: &mut Vec<u8>, codepoint: u32) -> Result<()> {
+        // Search for our replacement
+        let r: Option<&Replacement> = self.opts.codepoint_map.as_ref().and_then(|map| {
+            map.iter()
+                .rev()
+                .find(|m| m.range[0] <= codepoint && codepoint <= m.range[1])
+                .map(|m| &m.replacement)
+        });
+
+        // If no replacement, write it directly.
+        let Some(r) = r else {
+            return self.write_codepoint(out, codepoint);
+        };
+
+        match r {
+            Replacement::Codepoint(v) => self.write_codepoint(out, *v),
+            Replacement::String(s) => {
+                for c in s.chars() {
+                    self.write_codepoint(out, c as u32)?;
+                }
+                Ok(())
+            }
+        }
+    }
+
+    fn write_codepoint(&self, out: &mut Vec<u8>, codepoint: u32) -> Result<()> {
+        let push = |out: &mut Vec<u8>, cp: u32| -> Result<()> {
+            let c = char::from_u32(cp).ok_or_else(invalid_cp)?;
+            let mut b = [0u8; 4];
+            out.extend_from_slice(c.encode_utf8(&mut b).as_bytes());
+            Ok(())
+        };
+        match self.opts.emit {
+            Format::Plain | Format::Vt => push(out, codepoint),
+            Format::Html => match codepoint {
+                0x3C => {
+                    out.extend_from_slice(b"&lt;");
+                    Ok(())
+                }
+                0x3E => {
+                    out.extend_from_slice(b"&gt;");
+                    Ok(())
+                }
+                0x26 => {
+                    out.extend_from_slice(b"&amp;");
+                    Ok(())
+                }
+                0x22 => {
+                    out.extend_from_slice(b"&quot;");
+                    Ok(())
+                }
+                0x27 => {
+                    out.extend_from_slice(b"&#39;");
+                    Ok(())
+                }
+                _ => {
+                    // For HTML, emit ASCII (< 0x80) directly, but encode
+                    // all non-ASCII as numeric entities to avoid encoding
+                    // detection issues (fixes #9426). We can't set the
+                    // meta tag because we emit partial HTML so this ensures
+                    // proper unicode handling.
+                    if codepoint < 0x80 {
+                        push(out, codepoint)
+                    } else {
+                        write!(out, "&#{codepoint};")
+                    }
+                }
+            },
+        }
+    }
+
+    /// Returns the style for the given cell. If there is no styling this
+    /// will return the default style.
+    fn cell_style(&self, cell: Cell) -> Style {
+        match cell.content_tag() {
+            ContentTag::Codepoint | ContentTag::CodepointGrapheme => {
+                if cell.has_styling() {
+                    self.page.style(cell)
+                } else {
+                    Style::default()
+                }
+            }
+
+            ContentTag::BgColorPalette => Style {
+                bg_color: Color::Palette(cell.color_palette()),
+                ..Style::default()
+            },
+
+            ContentTag::BgColorRgb => Style {
+                bg_color: Color::Rgb(cell.color_rgb()),
+                ..Style::default()
+            },
+        }
+    }
+
+    fn format_style_open(&self, out: &mut Vec<u8>, style: &Style) -> Result<()> {
+        match self.opts.emit {
+            Format::Plain => unreachable!(),
+
+            Format::Vt => {
+                let mut formatter = style.formatter_vt();
+                formatter.palette = self.opts.palette.as_ref();
+                write!(out, "{formatter}")
+            }
+
+            // We use `display: inline` so that the div doesn't impact
+            // layout since we're primarily using it as a CSS wrapper.
+            Format::Html => {
+                let mut formatter = style.formatter_html();
+                formatter.palette = self.opts.palette.as_ref();
+                write!(out, "<div style=\"display: inline;{formatter}\">")
+            }
+        }
+    }
+
+    fn write_close_str(&mut self, writer: &mut dyn Write, s: &[u8]) -> Result<()> {
+        writer.write_all(s)?;
+        if let Some(m) = self.point_map.as_deref_mut() {
+            debug_assert!(m.capacity() > 0);
+            let last = m.last().copied().unwrap_or(Coordinate { x: 0, y: 0 });
+            m.extend(std::iter::repeat_n(last, s.len()));
+        }
+        Ok(())
+    }
+
+    fn format_style_close(&mut self, writer: &mut dyn Write) -> Result<()> {
+        let s: &[u8] = match self.opts.emit {
+            Format::Plain => return Ok(()),
+            Format::Vt => b"\x1b[0m",
+            Format::Html => b"</div>",
+        };
+        self.write_close_str(writer, s)
+    }
+
+    fn format_hyperlink_open(&self, out: &mut Vec<u8>, uri: &[u8]) -> Result<()> {
+        match self.opts.emit {
+            Format::Plain | Format::Vt => unreachable!(),
+
+            Format::Html => {
+                out.extend_from_slice(b"<a href=\"");
+                for &byte in uri {
+                    self.write_codepoint(out, u32::from(byte))?;
+                }
+                out.extend_from_slice(b"\">");
+                Ok(())
+            }
+        }
+    }
+
+    fn format_hyperlink_close(&mut self, writer: &mut dyn Write) -> Result<()> {
+        let s: &[u8] = match self.opts.emit {
+            Format::Html => b"</a>",
+            Format::Plain | Format::Vt => return Ok(()),
+        };
+        self.write_close_str(writer, s)
+    }
+}
+
+#[cfg(test)]
+mod tests;

crates/ghostty-terminal/src/formatter/tests/mod.rs

@@ -0,0 +1,53 @@
+//! Ported formatter.zig tests, split by Zig source line range:
+//! p1 = "Page plain ..." (Zig lines 1580-3287), p2 = "Page VT ...", "PageList ..."
+//! and "TerminalFormatter ..." (3288-4458), p3 = "Screen ...", "Terminal vt ...",
+//! "Page html ..." up to "Page VT style reset properly closes styles"
+//! (4459-5617), p4 = "Page codepoint_map ..." onwards (5618-end).
+#![allow(dead_code, clippy::needless_range_loop)]
+
+use super::*;
+use crate::{
+    page::Page,
+    page_list::Pin,
+    point::{Coordinate, Point},
+    terminal::{Options as TermOptions, Terminal},
+};
+
+mod p1;
+mod p2;
+mod p3;
+mod p4;
+
+/// Zig `Terminal.init(alloc, .{ .cols, .rows })`.
+pub(super) fn term(cols: u16, rows: u16) -> Terminal {
+    Terminal::new(TermOptions::new(cols, rows)).unwrap()
+}
+
+/// Zig `var s = t.vtStream(); try s.nextSlice(bytes)` (fresh stream per call;
+/// use `t.vt_stream()` directly if parser state must persist).
+pub(super) fn feed(t: &mut Terminal, bytes: &[u8]) {
+    let mut s = t.vt_stream();
+    s.next_slice(bytes).unwrap();
+}
+
+/// Zig `&pages.pages.last.?.data`.
+pub(super) fn last_page(t: &Terminal) -> &Page {
+    let pages = &t.screen().pages;
+    &pages.node(pages.last.unwrap()).unwrap().data
+}
+
+/// Zig `&pages.pages.first.?.data`.
+pub(super) fn first_page(t: &Terminal) -> &Page {
+    let pages = &t.screen().pages;
+    &pages.node(pages.first.unwrap()).unwrap().data
+}
+
+/// Zig `pages.pages.first.?.data.capacity.rows`.
+pub(super) fn first_page_rows(t: &Terminal) -> u16 {
+    first_page(t).capacity.rows
+}
+
+/// Format a whole `PageFormatter` into a string, returning the output.
+pub(super) fn fmt_str(f: PageFormatter<'_>) -> String {
+    f.format_string().unwrap()
+}

crates/ghostty-terminal/src/formatter/tests/p1.rs

@@ -0,0 +1,589 @@
+//! "Page plain ..." tests (formatter.zig lines 1580-3287).
+use super::*;
+
+struct Out {
+    s: String,
+    st: TrailingState,
+    map: Vec<Coordinate>,
+}
+
+/// Runs a PageFormatter over the last page with a point map attached.
+fn run(t: &Terminal, opts: &Options, cfg: impl FnOnce(&mut PageFormatter<'_>)) -> Out {
+    let page = last_page(t);
+    let mut map = Vec::new();
+    let mut buf = Vec::new();
+    let st = {
+        let mut f = PageFormatter::new(page, opts);
+        f.point_map = Some(&mut map);
+        cfg(&mut f);
+        f.format_with_state(&mut buf).unwrap()
+    };
+    Out {
+        s: String::from_utf8(buf).unwrap(),
+        st,
+        map,
+    }
+}
+
+fn c(x: u16, y: u32) -> Coordinate {
+    Coordinate { x, y }
+}
+
+/// `n` consecutive cells on row `y` starting at column `x0`.
+fn span(x0: u16, n: u16, y: u32) -> Vec<Coordinate> {
+    (0..n).map(|i| c(x0 + i, y)).collect()
+}
+
+fn setup(cols: u16, rows: u16, input: &str) -> Terminal {
+    let mut t = term(cols, rows);
+    feed(&mut t, input.as_bytes());
+    // Verify we have only a single page
+    let pages = &t.screen().pages;
+    assert!(pages.first.is_some());
+    assert_eq!(pages.first, pages.last);
+    t
+}
+
+fn unwrap_opts() -> Options {
+    Options {
+        unwrap: true,
+        ..Options::plain()
+    }
+}
+
+#[test]
+fn page_plain_single_line() {
+    let t = setup(80, 24, "hello, world");
+    let page = last_page(&t);
+    let o = run(&t, &Options::plain(), |_| {});
+    assert_eq!(o.s, "hello, world");
+    assert_eq!(o.st.rows, usize::from(page.size.rows));
+    assert_eq!(o.st.cells, usize::from(page.size.cols - 12));
+    assert_eq!(o.map, span(0, 12, 0));
+}
+
+#[test]
+fn page_plain_single_line_soft_wrapped_unwrapped() {
+    let t = setup(3, 5, "hello!");
+    let o = run(&t, &unwrap_opts(), |_| {});
+    assert_eq!(o.s, "hello!");
+    let mut e = span(0, 3, 0);
+    e.extend(span(0, 3, 1));
+    assert_eq!(o.map, e);
+}
+
+#[test]
+fn page_plain_single_wide_char() {
+    let t = setup(80, 24, "1A⚡");
+    let page = last_page(&t);
+    let opts = Options::plain();
+
+    // Full string
+    let o = run(&t, &opts, |_| {});
+    assert_eq!(o.s, "1A⚡");
+    assert_eq!(o.st.rows, usize::from(page.size.rows));
+    assert_eq!(o.st.cells, usize::from(page.size.cols - 4));
+    assert_eq!(o.map.len(), o.s.len());
+    for i in 2..o.s.len() {
+        assert_eq!(o.map[i], c(2, 0));
+    }
+
+    // Wide only (from start)
+    let o = run(&t, &opts, |f| f.start_x = 2);
+    assert_eq!(o.s, "⚡");
+    assert_eq!(o.st.rows, usize::from(page.size.rows));
+    assert_eq!(o.st.cells, usize::from(page.size.cols - 4));
+    assert_eq!(o.map, vec![c(2, 0); o.s.len()]);
+
+    // Wide only (from tail)
+    let o = run(&t, &opts, |f| f.start_x = 3);
+    assert_eq!(o.s, "⚡");
+    assert_eq!(o.st.rows, usize::from(page.size.rows));
+    assert_eq!(o.st.cells, usize::from(page.size.cols - 4));
+    assert_eq!(o.map, vec![c(2, 0); o.s.len()]);
+}
+
+#[test]
+fn page_plain_single_wide_char_soft_wrapped_unwrapped() {
+    let t = setup(3, 24, "1A⚡");
+    let page = last_page(&t);
+    let opts = unwrap_opts();
+
+    // Full string
+    let o = run(&t, &opts, |_| {});
+    assert_eq!(o.s, "1A⚡");
+    assert_eq!(o.st.rows, usize::from(page.size.rows - 1));
+    assert_eq!(o.st.cells, usize::from(page.size.cols - 2));
+    assert_eq!(o.map.len(), o.s.len());
+    for i in 2..o.s.len() {
+        assert_eq!(o.map[i], c(0, 1));
+    }
+
+    // Full string (ending on spacer head)
+    let o = run(&t, &opts, |f| {
+        f.end_x = Some(2);
+        f.end_y = Some(0);
+    });
+    assert_eq!(o.s, "1A⚡");
+    assert_eq!(o.map.len(), o.s.len());
+    for i in 2..o.s.len() {
+        assert_eq!(o.map[i], c(0, 1));
+    }
+
+    // Wide only (from start)
+    let o = run(&t, &opts, |f| f.start_x = 2);
+    assert_eq!(o.s, "⚡");
+    assert_eq!(o.st.rows, usize::from(page.size.rows - 1));
+    assert_eq!(o.st.cells, usize::from(page.size.cols - 2));
+    assert_eq!(o.map, vec![c(0, 1); o.s.len()]);
+
+    // Wide only (from tail). In Zig the formatter carried start_x = 2 over
+    // from the previous block; start_y = 1, start_x = 1.
+    let o = run(&t, &opts, |f| {
+        f.start_y = 1;
+        f.start_x = 1;
+    });
+    assert_eq!(o.s, "⚡");
+    assert_eq!(o.st.rows, usize::from(page.size.rows - 1));
+    assert_eq!(o.st.cells, usize::from(page.size.cols - 2));
+    assert_eq!(o.map, vec![c(0, 1); o.s.len()]);
+}
+
+#[test]
+fn page_plain_multiline() {
+    let t = setup(80, 24, "hello\r\nworld");
+    let page = last_page(&t);
+    let o = run(&t, &Options::plain(), |_| {});
+    assert_eq!(o.s, "hello\nworld");
+    assert_eq!(o.st.rows, usize::from(page.size.rows - 1));
+    assert_eq!(o.st.cells, usize::from(page.size.cols - 5));
+    let mut e = span(0, 5, 0);
+    e.push(c(4, 0)); // \n
+    e.extend(span(0, 5, 1));
+    assert_eq!(o.map, e);
+}
+
+#[test]
+fn page_plain_multiline_rectangle() {
+    let t = setup(80, 24, "hello\r\nworld");
+    let page = last_page(&t);
+    let o = run(&t, &Options::plain(), |f| {
+        f.start_x = 1;
+        f.end_x = Some(3);
+        f.rectangle = true;
+    });
+    assert_eq!(o.s, "ell\norl");
+    assert_eq!(o.st.rows, usize::from(page.size.rows - 1));
+    assert_eq!(o.st.cells, 0);
+    let mut e = span(1, 3, 0);
+    e.push(c(3, 0)); // \n
+    e.extend(span(1, 3, 1));
+    assert_eq!(o.map, e);
+}
+
+#[test]
+fn page_plain_multi_blank_lines() {
+    let t = setup(80, 24, "hello\r\n\r\n\r\nworld");
+    let page = last_page(&t);
+    let o = run(&t, &Options::plain(), |_| {});
+    assert_eq!(o.s, "hello\n\n\nworld");
+    assert_eq!(o.st.rows, usize::from(page.size.rows - 3));
+    assert_eq!(o.st.cells, usize::from(page.size.cols - 5));
+    let mut e = span(0, 5, 0);
+    e.push(c(4, 0)); // \n after row 0
+    e.push(c(0, 1)); // \n after blank row 1
+    e.push(c(0, 2)); // \n after blank row 2
+    e.extend(span(0, 5, 3));
+    assert_eq!(o.map, e);
+}
+
+#[test]
+fn page_plain_trailing_blank_lines() {
+    let t = setup(80, 24, "hello\r\nworld\r\n\r\n");
+    let page = last_page(&t);
+    // We expect there to be no trailing newlines because we can't
+    // differentiate trailing blank lines as being meaningful because the
+    // page formatter can't see the cursor position.
+    let o = run(&t, &Options::plain(), |_| {});
+    assert_eq!(o.s, "hello\nworld");
+    assert_eq!(o.st.rows, usize::from(page.size.rows - 1));
+    assert_eq!(o.st.cells, usize::from(page.size.cols - 5));
+    let mut e = span(0, 5, 0);
+    e.push(c(4, 0));
+    e.extend(span(0, 5, 1));
+    assert_eq!(o.map, e);
+}
+
+#[test]
+fn page_plain_trailing_whitespace() {
+    let t = setup(80, 24, "hello   \r\nworld   ");
+    let page = last_page(&t);
+    let o = run(&t, &Options::plain(), |_| {});
+    assert_eq!(o.s, "hello\nworld");
+    assert_eq!(o.st.rows, usize::from(page.size.rows - 1));
+    assert_eq!(o.st.cells, usize::from(page.size.cols - 5));
+    let mut e = span(0, 5, 0);
+    e.push(c(4, 0));
+    e.extend(span(0, 5, 1));
+    assert_eq!(o.map, e);
+}
+
+#[test]
+fn page_plain_trailing_whitespace_no_trim() {
+    let t = setup(80, 24, "hello   \r\nworld  ");
+    let page = last_page(&t);
+    let opts = Options {
+        trim: false,
+        ..Options::plain()
+    };
+    let o = run(&t, &opts, |_| {});
+    assert_eq!(o.s, "hello   \nworld  ");
+    assert_eq!(o.st.rows, usize::from(page.size.rows - 1));
+    assert_eq!(o.st.cells, usize::from(page.size.cols - 7));
+    let mut e = span(0, 8, 0);
+    e.push(c(7, 0));
+    e.extend(span(0, 7, 1));
+    assert_eq!(o.map, e);
+}
+
+#[test]
+fn page_plain_with_prior_trailing_state_rows() {
+    let t = setup(80, 24, "hello");
+    let page = last_page(&t);
+    let o = run(&t, &Options::plain(), |f| {
+        f.trailing_state = Some(TrailingState { rows: 2, cells: 0 });
+    });
+    assert_eq!(o.s, "\n\nhello");
+    assert_eq!(o.st.rows, usize::from(page.size.rows));
+    assert_eq!(o.st.cells, usize::from(page.size.cols - 5));
+    let mut e = vec![c(0, 0), c(0, 1)];
+    e.extend(span(0, 5, 0));
+    assert_eq!(o.map, e);
+}
+
+#[test]
+fn page_plain_with_prior_trailing_state_cells_no_wrapped_line() {
+    let t = setup(80, 24, "hello");
+    let page = last_page(&t);
+    let o = run(&t, &Options::plain(), |f| {
+        f.trailing_state = Some(TrailingState { rows: 0, cells: 3 });
+    });
+    // Blank cells are reset when row is not a wrap continuation
+    assert_eq!(o.s, "hello");
+    assert_eq!(o.st.rows, usize::from(page.size.rows));
+    assert_eq!(o.st.cells, usize::from(page.size.cols - 5));
+    assert_eq!(o.map, span(0, 5, 0));
+}
+
+#[test]
+fn page_plain_with_prior_trailing_state_cells_with_wrap_continuation() {
+    let mut t = setup(80, 24, "world");
+    // Surgically modify the first row to be a wrap continuation
+    {
+        let pages = &mut t.screen_mut().pages;
+        let id = pages.last.unwrap();
+        pages
+            .node_mut(id)
+            .unwrap()
+            .data
+            .get_row_mut(0)
+            .unwrap()
+            .set_wrap_continuation(true);
+    }
+    let page = last_page(&t);
+    let o = run(&t, &unwrap_opts(), |f| {
+        f.trailing_state = Some(TrailingState { rows: 0, cells: 3 });
+    });
+    // Blank cells are preserved when row is a wrap continuation with unwrap enabled
+    assert_eq!(o.s, "   world");
+    assert_eq!(o.st.rows, usize::from(page.size.rows));
+    assert_eq!(o.st.cells, usize::from(page.size.cols - 5));
+    // 3 spaces from prior trailing state (can't go back beyond (0,0)) + "world"
+    let mut e = vec![c(0, 0); 3];
+    e.extend(span(0, 5, 0));
+    assert_eq!(o.map, e);
+}
+
+#[test]
+fn page_plain_soft_wrapped_without_unwrap() {
+    let t = setup(10, 24, "hello world test");
+    let page = last_page(&t);
+    let o = run(&t, &Options::plain(), |_| {});
+    // Without unwrap, wrapped lines show as separate lines
+    assert_eq!(o.s, "hello worl\nd test");
+    assert_eq!(o.st.rows, usize::from(page.size.rows - 1));
+    assert_eq!(o.st.cells, usize::from(page.size.cols - 6));
+    let mut e = span(0, 10, 0);
+    e.push(c(9, 0)); // \n
+    e.extend(span(0, 6, 1));
+    assert_eq!(o.map, e);
+}
+
+#[test]
+fn page_plain_soft_wrapped_with_unwrap() {
+    let t = setup(10, 24, "hello world test");
+    let page = last_page(&t);
+    let o = run(&t, &unwrap_opts(), |_| {});
+    // With unwrap, wrapped lines are joined together
+    assert_eq!(o.s, "hello world test");
+    assert_eq!(o.st.rows, usize::from(page.size.rows - 1));
+    assert_eq!(o.st.cells, usize::from(page.size.cols - 6));
+    let mut e = span(0, 10, 0);
+    e.extend(span(0, 6, 1));
+    assert_eq!(o.map, e);
+}
+
+#[test]
+fn page_plain_soft_wrapped_3_lines_without_unwrap() {
+    let t = setup(10, 24, "hello world this is a test");
+    let page = last_page(&t);
+    let o = run(&t, &Options::plain(), |_| {});
+    assert_eq!(o.s, "hello worl\nd this is\na test");
+    assert_eq!(o.st.rows, usize::from(page.size.rows - 2));
+    assert_eq!(o.st.cells, usize::from(page.size.cols - 6));
+    let mut e = span(0, 10, 0);
+    e.push(c(9, 0)); // \n
+    e.extend(span(0, 9, 1));
+    e.push(c(8, 1)); // \n
+    e.extend(span(0, 6, 2));
+    assert_eq!(o.map, e);
+}
+
+#[test]
+fn page_plain_soft_wrapped_3_lines_with_unwrap() {
+    let t = setup(10, 24, "hello world this is a test");
+    let page = last_page(&t);
+    let o = run(&t, &unwrap_opts(), |_| {});
+    assert_eq!(o.s, "hello world this is a test");
+    assert_eq!(o.st.rows, usize::from(page.size.rows - 2));
+    assert_eq!(o.st.cells, usize::from(page.size.cols - 6));
+    let mut e = span(0, 10, 0);
+    e.extend(span(0, 10, 1));
+    e.extend(span(0, 6, 2));
+    assert_eq!(o.map, e);
+}
+
+#[test]
+fn page_plain_start_y_subset() {
+    let t = setup(80, 24, "hello\r\nworld\r\ntest");
+    let page = last_page(&t);
+    let o = run(&t, &Options::plain(), |f| f.start_y = 1);
+    assert_eq!(o.s, "world\ntest");
+    assert_eq!(o.st.rows, usize::from(page.size.rows - 2));
+    assert_eq!(o.st.cells, usize::from(page.size.cols - 4));
+    let mut e = span(0, 5, 1);
+    e.push(c(4, 1)); // \n
+    e.extend(span(0, 4, 2));
+    assert_eq!(o.map, e);
+}
+
+#[test]
+fn page_plain_end_y_subset() {
+    let t = setup(80, 24, "hello\r\nworld\r\ntest");
+    let page = last_page(&t);
+    let o = run(&t, &Options::plain(), |f| f.end_y = Some(1));
+    assert_eq!(o.s, "hello\nworld");
+    assert_eq!(o.st.rows, 1);
+    assert_eq!(o.st.cells, usize::from(page.size.cols - 5));
+    let mut e = span(0, 5, 0);
+    e.push(c(4, 0)); // \n
+    e.extend(span(0, 5, 1));
+    assert_eq!(o.map, e);
+}
+
+#[test]
+fn page_plain_start_y_and_end_y_range() {
+    let t = setup(80, 24, "hello\r\nworld\r\ntest\r\nfoo");
+    let page = last_page(&t);
+    let o = run(&t, &Options::plain(), |f| {
+        f.start_y = 1;
+        f.end_y = Some(2);
+    });
+    assert_eq!(o.s, "world\ntest");
+    assert_eq!(o.st.rows, 1);
+    assert_eq!(o.st.cells, usize::from(page.size.cols - 4));
+    let mut e = span(0, 5, 1);
+    e.push(c(4, 1)); // \n
+    e.extend(span(0, 4, 2));
+    assert_eq!(o.map, e);
+}
+
+#[test]
+fn page_plain_start_y_out_of_bounds() {
+    let t = setup(80, 24, "hello");
+    let o = run(&t, &Options::plain(), |f| f.start_y = 30);
+    assert_eq!(o.s, "");
+    assert_eq!(o.st.rows, 0);
+    assert_eq!(o.st.cells, 0);
+    assert_eq!(o.map.len(), 0);
+}
+
+#[test]
+fn page_plain_end_y_greater_than_rows() {
+    let t = setup(80, 24, "hello");
+    let page = last_page(&t);
+    let o = run(&t, &Options::plain(), |f| f.end_y = Some(30));
+    // Should clamp to page.size.rows and work normally
+    assert_eq!(o.s, "hello");
+    assert_eq!(o.st.rows, usize::from(page.size.rows));
+    assert_eq!(o.st.cells, usize::from(page.size.cols - 5));
+    assert_eq!(o.map, span(0, 5, 0));
+}
+
+#[test]
+fn page_plain_end_y_less_than_start_y() {
+    let t = setup(80, 24, "hello");
+    let o = run(&t, &Options::plain(), |f| {
+        f.start_y = 5;
+        f.end_y = Some(2);
+    });
+    assert_eq!(o.s, "");
+    assert_eq!(o.st.rows, 0);
+    assert_eq!(o.st.cells, 0);
+    assert_eq!(o.map.len(), 0);
+}
+
+#[test]
+fn page_plain_start_x_on_first_row_only() {
+    let t = setup(80, 24, "hello world");
+    let page = last_page(&t);
+    let o = run(&t, &Options::plain(), |f| f.start_x = 6);
+    assert_eq!(o.s, "world");
+    assert_eq!(o.st.rows, usize::from(page.size.rows));
+    assert_eq!(o.st.cells, usize::from(page.size.cols - 11));
+    assert_eq!(o.map, span(6, 5, 0));
+}
+
+#[test]
+fn page_plain_end_x_on_last_row_only() {
+    let t = setup(80, 24, "first line\r\nsecond line\r\nthird line");
+    let o = run(&t, &Options::plain(), |f| {
+        f.end_y = Some(2);
+        f.end_x = Some(4);
+    });
+    assert_eq!(o.s, "first line\nsecond line\nthird");
+    assert_eq!(o.st.rows, 1);
+    assert_eq!(o.st.cells, 0);
+    let mut e = span(0, 10, 0);
+    e.push(c(9, 0)); // \n
+    e.extend(span(0, 11, 1));
+    e.push(c(10, 1)); // \n
+    e.extend(span(0, 5, 2));
+    assert_eq!(o.map, e);
+}
+
+#[test]
+fn page_plain_start_x_and_end_x_multiline() {
+    let t = setup(80, 24, "hello world\r\ntest case\r\nfoo bar");
+    let o = run(&t, &Options::plain(), |f| {
+        f.start_x = 6;
+        f.end_y = Some(2);
+        f.end_x = Some(2);
+    });
+    // First row: "world" (start_x=6 to end of row)
+    // Second row: "test case" (full row)
+    // Third row: "foo" (start to end_x=2, inclusive)
+    assert_eq!(o.s, "world\ntest case\nfoo");
+    assert_eq!(o.st.rows, 1);
+    assert_eq!(o.st.cells, 0);
+    let mut e = span(6, 5, 0);
+    e.push(c(10, 0)); // \n
+    e.extend(span(0, 9, 1));
+    e.push(c(8, 1)); // \n
+    e.extend(span(0, 3, 2));
+    assert_eq!(o.map, e);
+}
+
+#[test]
+fn page_plain_start_x_out_of_bounds() {
+    let t = setup(80, 24, "hello");
+    let o = run(&t, &Options::plain(), |f| f.start_x = 100);
+    assert_eq!(o.s, "");
+    assert_eq!(o.st.rows, 0);
+    assert_eq!(o.st.cells, 0);
+    assert_eq!(o.map.len(), 0);
+}
+
+#[test]
+fn page_plain_end_x_greater_than_cols() {
+    let t = setup(80, 24, "hello");
+    let page = last_page(&t);
+    let o = run(&t, &Options::plain(), |f| f.end_x = Some(100));
+    assert_eq!(o.s, "hello");
+    assert_eq!(o.st.rows, usize::from(page.size.rows));
+    assert_eq!(o.st.cells, usize::from(page.size.cols - 5));
+    assert_eq!(o.map, span(0, 5, 0));
+}
+
+#[test]
+fn page_plain_end_x_less_than_start_x_single_row() {
+    let t = setup(80, 24, "hello");
+    let o = run(&t, &Options::plain(), |f| {
+        f.start_x = 10;
+        f.end_y = Some(0);
+        f.end_x = Some(5);
+    });
+    assert_eq!(o.s, "");
+    assert_eq!(o.st.rows, 0);
+    assert_eq!(o.st.cells, 0);
+    assert_eq!(o.map.len(), 0);
+}
+
+#[test]
+fn page_plain_start_y_non_zero_ignores_trailing_state() {
+    let t = setup(80, 24, "hello\r\nworld");
+    let page = last_page(&t);
+    let o = run(&t, &Options::plain(), |f| {
+        f.start_y = 1;
+        f.trailing_state = Some(TrailingState { rows: 5, cells: 10 });
+    });
+    // Should NOT output the 5 newlines from trailing_state because start_y is non-zero
+    assert_eq!(o.s, "world");
+    assert_eq!(o.st.rows, usize::from(page.size.rows - 1));
+    assert_eq!(o.st.cells, usize::from(page.size.cols - 5));
+    assert_eq!(o.map, span(0, 5, 1));
+}
+
+#[test]
+fn page_plain_start_x_non_zero_ignores_trailing_state() {
+    let t = setup(80, 24, "hello world");
+    let page = last_page(&t);
+    let o = run(&t, &Options::plain(), |f| {
+        f.start_x = 6;
+        f.trailing_state = Some(TrailingState { rows: 2, cells: 8 });
+    });
+    // Should NOT output the 2 newlines or 8 spaces from trailing_state
+    assert_eq!(o.s, "world");
+    assert_eq!(o.st.rows, usize::from(page.size.rows));
+    assert_eq!(o.st.cells, usize::from(page.size.cols - 11));
+    assert_eq!(o.map, span(6, 5, 0));
+}
+
+#[test]
+fn page_plain_start_y_and_start_x_zero_uses_trailing_state() {
+    let t = setup(80, 24, "hello");
+    let page = last_page(&t);
+    let o = run(&t, &Options::plain(), |f| {
+        f.start_y = 0;
+        f.start_x = 0;
+        f.trailing_state = Some(TrailingState { rows: 2, cells: 0 });
+    });
+    // SHOULD output the 2 newlines from trailing_state
+    assert_eq!(o.s, "\n\nhello");
+    assert_eq!(o.st.rows, usize::from(page.size.rows));
+    assert_eq!(o.st.cells, usize::from(page.size.cols - 5));
+    let mut e = vec![c(0, 0), c(0, 1)];
+    e.extend(span(0, 5, 0));
+    assert_eq!(o.map, e);
+}
+
+#[test]
+fn page_plain_single_line_with_styling() {
+    let t = setup(80, 24, "hello, \x1b[1mworld\x1b[0m");
+    let page = last_page(&t);
+    let o = run(&t, &Options::plain(), |_| {});
+    assert_eq!(o.s, "hello, world");
+    assert_eq!(o.st.rows, usize::from(page.size.rows));
+    assert_eq!(o.st.cells, usize::from(page.size.cols - 12));
+    assert_eq!(o.map, span(0, 12, 0));
+}

crates/ghostty-terminal/src/formatter/tests/p2.rs

@@ -0,0 +1,686 @@
+use super::*;
+
+/// Format the last page of `t` with a page formatter and a point map.
+fn page_fmt(t: &Terminal, opts: &Options) -> (String, Vec<Coordinate>) {
+    let mut point_map = Vec::new();
+    let mut f = PageFormatter::new(last_page(t), opts);
+    f.point_map = Some(&mut point_map);
+    let out = f.format_string().unwrap();
+    (out, point_map)
+}
+
+fn trim_start<'a>(s: &'a str, chars: &[char]) -> &'a str {
+    s.trim_start_matches(chars)
+}
+
+fn coord(x: u16, y: u32) -> Coordinate {
+    Coordinate { x, y }
+}
+
+#[test]
+fn page_vt_single_line_plain_text() {
+    let mut t = term(80, 24);
+    feed(&mut t, b"hello");
+    let (output, point_map) = page_fmt(&t, &Options::vt());
+    assert_eq!(output, "hello");
+    assert_eq!(point_map.len(), output.len());
+    for i in 0..5 {
+        assert_eq!(point_map[i], coord(i as u16, 0));
+    }
+}
+
+#[test]
+fn page_vt_single_line_with_bold() {
+    let mut t = term(80, 24);
+    feed(&mut t, b"\x1b[1mhello\x1b[0m");
+    let (output, point_map) = page_fmt(&t, &Options::vt());
+    assert_eq!(output, "\x1b[0m\x1b[1mhello\x1b[0m");
+    assert_eq!(point_map.len(), output.len());
+    for i in 0..8 {
+        assert_eq!(point_map[i], coord(0, 0));
+    }
+    for i in 0..5 {
+        assert_eq!(point_map[8 + i], coord(i as u16, 0));
+    }
+}
+
+#[test]
+fn page_vt_multiple_styles() {
+    let mut t = term(80, 24);
+    feed(&mut t, b"\x1b[1mhello \x1b[3mworld\x1b[0m");
+    let (output, point_map) = page_fmt(&t, &Options::vt());
+    assert_eq!(
+        output,
+        "\x1b[0m\x1b[1mhello \x1b[0m\x1b[1m\x1b[3mworld\x1b[0m"
+    );
+    assert_eq!(point_map.len(), output.len());
+}
+
+#[test]
+fn page_vt_with_foreground_color() {
+    let mut t = term(80, 24);
+    feed(&mut t, b"\x1b[31mred\x1b[0m");
+    let (output, point_map) = page_fmt(&t, &Options::vt());
+    assert_eq!(output, "\x1b[0m\x1b[38;5;1mred\x1b[0m");
+    assert_eq!(point_map.len(), output.len());
+    for i in 0..13 {
+        assert_eq!(point_map[i], coord(0, 0));
+    }
+    for i in 0..3 {
+        assert_eq!(point_map[13 + i], coord(i as u16, 0));
+    }
+}
+
+#[test]
+fn page_vt_with_background_and_foreground_colors() {
+    let mut t = term(80, 24);
+    feed(&mut t, b"hello");
+    let mut opts = Options::vt();
+    opts.background = Some(Rgb {
+        r: 0x12,
+        g: 0x34,
+        b: 0x56,
+    });
+    opts.foreground = Some(Rgb {
+        r: 0xab,
+        g: 0xcd,
+        b: 0xef,
+    });
+    let output = fmt_str(PageFormatter::new(last_page(&t), &opts));
+    assert_eq!(
+        output,
+        "\x1b]10;rgb:ab/cd/ef\x1b\\\x1b]11;rgb:12/34/56\x1b\\hello"
+    );
+}
+
+#[test]
+fn page_vt_multi_line_with_styles() {
+    let mut t = term(80, 24);
+    feed(&mut t, b"\x1b[1mfirst\x1b[0m\r\n\x1b[3msecond\x1b[0m");
+    let (output, point_map) = page_fmt(&t, &Options::vt());
+    // Note: style is reset before newline to prevent background colors from
+    // bleeding to the next line's leading cells.
+    assert_eq!(
+        output,
+        "\x1b[0m\x1b[1mfirst\x1b[0m\r\n\x1b[0m\x1b[3msecond\x1b[0m"
+    );
+    assert_eq!(point_map.len(), output.len());
+}
+
+#[test]
+fn page_vt_duplicate_style_not_emitted_twice() {
+    let mut t = term(80, 24);
+    feed(&mut t, b"\x1b[1mhel\x1b[1mlo\x1b[0m");
+    let (output, point_map) = page_fmt(&t, &Options::vt());
+    assert_eq!(output, "\x1b[0m\x1b[1mhello\x1b[0m");
+    assert_eq!(point_map.len(), output.len());
+}
+
+fn node_of_first(t: &Terminal) -> crate::page_list::NodeId {
+    t.screen().pages.first.unwrap()
+}
+
+fn node_of_last(t: &Terminal) -> crate::page_list::NodeId {
+    t.screen().pages.last.unwrap()
+}
+
+fn list_fmt(t: &Terminal, opts: Options) -> (String, Vec<Pin>) {
+    let mut pin_map = Vec::new();
+    let mut f = PageListFormatter::new(&t.screen().pages, opts);
+    f.pin_map = Some(&mut pin_map);
+    let out = f.format_string().unwrap();
+    (out, pin_map)
+}
+
+#[test]
+fn pagelist_plain_single_line() {
+    let mut t = term(80, 24);
+    feed(&mut t, b"hello, world");
+    let (output, pin_map) = list_fmt(&t, Options::plain());
+    assert_eq!(output, "hello, world");
+    assert_eq!(pin_map.len(), output.len());
+    let node = node_of_first(&t);
+    for i in 0..output.len() {
+        assert_eq!(
+            pin_map[i],
+            Pin {
+                node,
+                x: i as u16,
+                y: 0,
+                garbage: false
+            }
+        );
+    }
+}
+
+#[test]
+fn pagelist_plain_spanning_two_pages() {
+    let mut t = term(80, 24);
+    let first_page_rows = first_page_rows(&t);
+
+    // Fill the first page almost completely
+    for _ in 0..first_page_rows - 1 {
+        feed(&mut t, b"\r\n");
+    }
+    feed(&mut t, b"page one");
+
+    // Verify we're still on one page
+    assert_eq!(t.screen().pages.first, t.screen().pages.last);
+
+    // Add one more newline to push content to a second page
+    feed(&mut t, b"\r\n");
+    assert_ne!(t.screen().pages.first, t.screen().pages.last);
+
+    // Write content on the second page
+    feed(&mut t, b"page two");
+
+    let (full_output, pin_map) = list_fmt(&t, Options::plain());
+    let output = trim_start(&full_output, &['\n']);
+    assert_eq!(output, "page one\npage two");
+
+    assert_eq!(pin_map.len(), full_output.len());
+    let first_node = node_of_first(&t);
+    let last_node = node_of_last(&t);
+    let trimmed_count = full_output.len() - output.len();
+
+    // First part (trimmed blank lines) maps to first node
+    for p in &pin_map[..trimmed_count] {
+        assert_eq!(p.node, first_node);
+    }
+
+    // "page one" (8 chars) maps to first node
+    for i in 0..8 {
+        let idx = trimmed_count + i;
+        assert_eq!(pin_map[idx].node, first_node);
+        assert_eq!(pin_map[idx].x, i as u16);
+    }
+
+    // \n - maps to last node as it represents the transition to new page
+    assert_eq!(pin_map[trimmed_count + 8].node, last_node);
+
+    // "page two" (8 chars) maps to last node
+    for i in 0..8 {
+        let idx = trimmed_count + 9 + i;
+        assert_eq!(pin_map[idx].node, last_node);
+        assert_eq!(pin_map[idx].x, i as u16);
+    }
+}
+
+#[test]
+fn pagelist_soft_wrapped_line_spanning_two_pages_without_unwrap() {
+    let mut t = term(10, 3);
+    let first_page_rows = first_page_rows(&t);
+
+    // Fill the first page with soft-wrapped content
+    for _ in 0..first_page_rows - 1 {
+        feed(&mut t, b"\r\n");
+    }
+    feed(&mut t, b"hello world test");
+
+    // Verify we're on two pages due to wrapping
+    assert_ne!(t.screen().pages.first, t.screen().pages.last);
+
+    let (full_output, pin_map) = list_fmt(&t, Options::plain());
+    let output = trim_start(&full_output, &['\n']);
+    assert_eq!(output, "hello worl\nd test");
+
+    assert_eq!(pin_map.len(), full_output.len());
+    let first_node = node_of_first(&t);
+    let last_node = node_of_last(&t);
+    let trimmed_count = full_output.len() - output.len();
+
+    for p in &pin_map[..trimmed_count] {
+        assert_eq!(p.node, first_node);
+    }
+    for i in 0..10 {
+        assert_eq!(pin_map[trimmed_count + i].node, first_node);
+    }
+
+    // \n - maps to last node as it represents the transition to new page
+    assert_eq!(pin_map[trimmed_count + 10].node, last_node);
+
+    // "d test" (6 chars) maps to last node
+    for i in 0..6 {
+        assert_eq!(pin_map[trimmed_count + 11 + i].node, last_node);
+    }
+}
+
+#[test]
+fn pagelist_soft_wrapped_line_spanning_two_pages_with_unwrap() {
+    let mut t = term(10, 3);
+    let first_page_rows = first_page_rows(&t);
+
+    for _ in 0..first_page_rows - 1 {
+        feed(&mut t, b"\r\n");
+    }
+    feed(&mut t, b"hello world test");
+
+    assert_ne!(t.screen().pages.first, t.screen().pages.last);
+
+    let mut opts = Options::plain();
+    opts.unwrap = true;
+    let (full_output, pin_map) = list_fmt(&t, opts);
+    let output = trim_start(&full_output, &['\r', '\n']);
+    assert_eq!(output, "hello world test");
+
+    assert_eq!(pin_map.len(), full_output.len());
+    let first_node = node_of_first(&t);
+    let last_node = node_of_last(&t);
+    let trimmed_count = full_output.len() - output.len();
+
+    for p in &pin_map[..trimmed_count] {
+        assert_eq!(p.node, first_node);
+    }
+    for i in 0..10 {
+        assert_eq!(pin_map[trimmed_count + i].node, first_node);
+    }
+    for i in 0..6 {
+        assert_eq!(pin_map[trimmed_count + 10 + i].node, last_node);
+    }
+}
+
+#[test]
+fn pagelist_vt_spanning_two_pages() {
+    let mut t = term(80, 24);
+    let first_page_rows = first_page_rows(&t);
+
+    // Fill the first page almost completely
+    for _ in 0..first_page_rows - 1 {
+        feed(&mut t, b"\r\n");
+    }
+    feed(&mut t, b"\x1b[1mpage one");
+
+    assert_eq!(t.screen().pages.first, t.screen().pages.last);
+
+    feed(&mut t, b"\r\n");
+    assert_ne!(t.screen().pages.first, t.screen().pages.last);
+
+    // New content is still styled
+    feed(&mut t, b"page two");
+
+    let (full_output, pin_map) = list_fmt(&t, Options::vt());
+    let output = trim_start(&full_output, &['\r', '\n']);
+    assert_eq!(
+        output,
+        "\x1b[0m\x1b[1mpage one\x1b[0m\r\n\x1b[0m\x1b[1mpage two\x1b[0m"
+    );
+
+    assert_eq!(pin_map.len(), full_output.len());
+    let first_node = node_of_first(&t);
+    let last_node = node_of_last(&t);
+
+    let first_count = pin_map.iter().filter(|p| p.node == first_node).count();
+    let last_count = pin_map.iter().filter(|p| p.node == last_node).count();
+    assert!(first_count > 0);
+    assert!(last_count > 0);
+}
+
+#[test]
+fn pagelist_plain_with_x_offset_on_single_page() {
+    let mut t = term(80, 24);
+    feed(&mut t, b"hello world\r\ntest case\r\nfoo bar");
+
+    let node = node_of_first(&t);
+    let mut pin_map = Vec::new();
+    let mut f = PageListFormatter::new(&t.screen().pages, Options::plain());
+    f.top_left = Some(Pin {
+        node,
+        y: 0,
+        x: 6,
+        garbage: false,
+    });
+    f.bottom_right = Some(Pin {
+        node,
+        y: 2,
+        x: 2,
+        garbage: false,
+    });
+    f.pin_map = Some(&mut pin_map);
+    let output = f.format_string().unwrap();
+    assert_eq!(output, "world\ntest case\nfoo");
+
+    assert_eq!(pin_map.len(), output.len());
+    for p in &pin_map {
+        assert_eq!(p.node, node);
+    }
+
+    // "world" starts at x=6, y=0
+    for i in 0..5 {
+        assert_eq!(pin_map[i].x, 6 + i as u16);
+        assert_eq!(pin_map[i].y, 0);
+    }
+}
+
+#[test]
+fn pagelist_plain_with_x_offset_spanning_two_pages() {
+    let mut t = term(80, 24);
+    let first_page_rows = first_page_rows(&t);
+
+    for _ in 0..first_page_rows - 1 {
+        feed(&mut t, b"\r\n");
+    }
+    feed(&mut t, b"hello world");
+
+    assert_eq!(t.screen().pages.first, t.screen().pages.last);
+
+    feed(&mut t, b"\r\n");
+    assert_ne!(t.screen().pages.first, t.screen().pages.last);
+
+    feed(&mut t, b"foo bar test");
+
+    let first_node = node_of_first(&t);
+    let last_node = node_of_last(&t);
+    let first_rows = t.screen().pages.node(first_node).unwrap().data.size.rows;
+
+    let mut pin_map = Vec::new();
+    let mut f = PageListFormatter::new(&t.screen().pages, Options::plain());
+    f.top_left = Some(Pin {
+        node: first_node,
+        y: first_rows - 1,
+        x: 6,
+        garbage: false,
+    });
+    f.bottom_right = Some(Pin {
+        node: last_node,
+        y: 1,
+        x: 2,
+        garbage: false,
+    });
+    f.pin_map = Some(&mut pin_map);
+    let full_output = f.format_string().unwrap();
+    let output = trim_start(&full_output, &['\n']);
+    assert_eq!(output, "world\nfoo");
+
+    assert_eq!(pin_map.len(), full_output.len());
+    let trimmed_count = full_output.len() - output.len();
+
+    // "world" (5 chars) from first page
+    for i in 0..5 {
+        let idx = trimmed_count + i;
+        assert_eq!(pin_map[idx].node, first_node);
+        assert_eq!(pin_map[idx].x, 6 + i as u16);
+    }
+
+    // \n - maps to last node as it represents the transition to new page
+    assert_eq!(pin_map[trimmed_count + 5].node, last_node);
+
+    // "foo" (3 chars) from last page
+    for i in 0..3 {
+        let idx = trimmed_count + 6 + i;
+        assert_eq!(pin_map[idx].node, last_node);
+        assert_eq!(pin_map[idx].x, i as u16);
+    }
+}
+
+#[test]
+fn pagelist_plain_with_start_x_only() {
+    let mut t = term(80, 24);
+    feed(&mut t, b"hello world");
+
+    let node = node_of_first(&t);
+    let mut pin_map = Vec::new();
+    let mut f = PageListFormatter::new(&t.screen().pages, Options::plain());
+    f.top_left = Some(Pin {
+        node,
+        y: 0,
+        x: 6,
+        garbage: false,
+    });
+    f.pin_map = Some(&mut pin_map);
+    let output = f.format_string().unwrap();
+    assert_eq!(output, "world");
+
+    assert_eq!(pin_map.len(), output.len());
+    for i in 0..5 {
+        assert_eq!(pin_map[i].node, node);
+        assert_eq!(pin_map[i].x, 6 + i as u16);
+        assert_eq!(pin_map[i].y, 0);
+    }
+}
+
+#[test]
+fn pagelist_plain_with_end_x_only() {
+    let mut t = term(80, 24);
+    feed(&mut t, b"hello world\r\ntest");
+
+    let node = node_of_first(&t);
+    let mut pin_map = Vec::new();
+    let mut f = PageListFormatter::new(&t.screen().pages, Options::plain());
+    f.bottom_right = Some(Pin {
+        node,
+        y: 1,
+        x: 2,
+        garbage: false,
+    });
+    f.pin_map = Some(&mut pin_map);
+    let output = f.format_string().unwrap();
+    assert_eq!(output, "hello world\ntes");
+
+    assert_eq!(pin_map.len(), output.len());
+
+    for i in 0..11 {
+        assert_eq!(pin_map[i].node, node);
+        assert_eq!(pin_map[i].x, i as u16);
+        assert_eq!(pin_map[i].y, 0);
+    }
+
+    // \n
+    assert_eq!(pin_map[11].node, node);
+
+    for i in 0..3 {
+        assert_eq!(pin_map[12 + i].node, node);
+        assert_eq!(pin_map[12 + i].x, i as u16);
+        assert_eq!(pin_map[12 + i].y, 1);
+    }
+}
+
+fn rect_format(t: &Terminal, tl: (u16, u32), br: (u16, u32)) -> String {
+    let pages = &t.screen().pages;
+    let mut f = PageListFormatter::new(pages, Options::plain());
+    f.top_left = Some(
+        pages
+            .pin(Point::Screen(Coordinate { x: tl.0, y: tl.1 }))
+            .unwrap(),
+    );
+    f.bottom_right = Some(
+        pages
+            .pin(Point::Screen(Coordinate { x: br.0, y: br.1 }))
+            .unwrap(),
+    );
+    f.rectangle = true;
+    f.format_string().unwrap()
+}
+
+#[test]
+fn pagelist_plain_rectangle_basic() {
+    let mut t = term(30, 5);
+    feed(&mut t, b"Lorem ipsum dolor\r\n");
+    feed(&mut t, b"sit amet, consectetur\r\n");
+    feed(&mut t, b"adipiscing elit, sed do\r\n");
+    feed(&mut t, b"eiusmod tempor incididunt\r\n");
+    feed(&mut t, b"ut labore et dolore");
+
+    let output = rect_format(&t, (2, 1), (6, 3));
+    assert_eq!(output, "t ame\nipisc\nusmod");
+}
+
+#[test]
+fn pagelist_plain_rectangle_with_eol() {
+    let mut t = term(30, 5);
+    feed(&mut t, b"Lorem ipsum dolor\r\n");
+    feed(&mut t, b"sit amet, consectetur\r\n");
+    feed(&mut t, b"adipiscing elit, sed do\r\n");
+    feed(&mut t, b"eiusmod tempor incididunt\r\n");
+    feed(&mut t, b"ut labore et dolore");
+
+    let output = rect_format(&t, (12, 0), (26, 4));
+    assert_eq!(
+        output,
+        "dolor\nnsectetur\nlit, sed do\nor incididunt\n dolore"
+    );
+}
+
+#[test]
+fn pagelist_plain_rectangle_more_complex_with_breaks() {
+    let mut t = term(30, 8);
+    feed(&mut t, b"Lorem ipsum dolor\r\n");
+    feed(&mut t, b"sit amet, consectetur\r\n");
+    feed(&mut t, b"adipiscing elit, sed do\r\n");
+    feed(&mut t, b"eiusmod tempor incididunt\r\n");
+    feed(&mut t, b"ut labore et dolore\r\n");
+    feed(&mut t, b"\r\n");
+    feed(&mut t, b"magna aliqua. Ut enim\r\n");
+    feed(&mut t, b"ad minim veniam, quis");
+
+    let output = rect_format(&t, (11, 2), (26, 7));
+    assert_eq!(
+        output,
+        "elit, sed do\npor incididunt\nt dolore\n\na. Ut enim\nniam, quis"
+    );
+}
+
+#[test]
+fn terminal_formatter_plain_no_selection() {
+    let mut t = term(80, 24);
+    feed(&mut t, b"hello\r\nworld");
+    let f = TerminalFormatter::new(&t, Options::plain());
+    assert_eq!(f.format_string().unwrap(), "hello\nworld");
+}
+
+#[test]
+fn terminal_formatter_vt_with_palette() {
+    let mut t = term(80, 24);
+
+    // Modify some palette colors using VT sequences
+    feed(&mut t, b"\x1b]4;0;rgb:12/34/56\x1b\\");
+    feed(&mut t, b"\x1b]4;1;rgb:ab/cd/ef\x1b\\");
+    feed(&mut t, b"\x1b]4;255;rgb:ff/00/ff\x1b\\");
+    feed(&mut t, b"test");
+
+    let output = TerminalFormatter::new(&t, Options::vt())
+        .format_string()
+        .unwrap();
+
+    // Create a second terminal and apply the output
+    let mut t2 = term(80, 24);
+    feed(&mut t2, output.as_bytes());
+
+    // Verify the palettes match
+    for i in [0, 1, 255] {
+        assert_eq!(t.colors.palette.current[i], t2.colors.palette.current[i]);
+    }
+}
+
+fn line2_selection(t: &Terminal) -> Selection {
+    let pages = &t.screen().pages;
+    Selection::new(
+        pages.pin(Point::Active(Coordinate { x: 0, y: 1 })).unwrap(),
+        pages.pin(Point::Active(Coordinate { x: 4, y: 1 })).unwrap(),
+        false,
+    )
+}
+
+#[test]
+fn terminal_formatter_with_selection() {
+    let mut t = term(80, 24);
+    feed(&mut t, b"line1\r\nline2\r\nline3");
+    let sel = line2_selection(&t);
+    let mut f = TerminalFormatter::new(&t, Options::plain());
+    f.content = Content::Selection(Some(sel));
+    assert_eq!(f.format_string().unwrap(), "line2");
+}
+
+#[test]
+fn terminal_formatter_plain_with_pin_map() {
+    let mut t = term(80, 24);
+    feed(&mut t, b"hello, world");
+
+    let mut pin_map = Vec::new();
+    let mut f = TerminalFormatter::new(&t, Options::plain());
+    f.pin_map = Some(&mut pin_map);
+    let output = f.format_string().unwrap();
+    assert_eq!(output, "hello, world");
+
+    assert_eq!(pin_map.len(), output.len());
+    let node = node_of_first(&t);
+    for i in 0..output.len() {
+        assert_eq!(
+            pin_map[i],
+            Pin {
+                node,
+                x: i as u16,
+                y: 0,
+                garbage: false
+            }
+        );
+    }
+}
+
+#[test]
+fn terminal_formatter_plain_multiline_with_pin_map() {
+    let mut t = term(80, 24);
+    feed(&mut t, b"hello\r\nworld");
+
+    let mut pin_map = Vec::new();
+    let mut f = TerminalFormatter::new(&t, Options::plain());
+    f.pin_map = Some(&mut pin_map);
+    let output = f.format_string().unwrap();
+    assert_eq!(output, "hello\nworld");
+
+    assert_eq!(pin_map.len(), output.len());
+    let node = node_of_first(&t);
+    for i in 0..5 {
+        assert_eq!(pin_map[i].node, node);
+        assert_eq!(pin_map[i].x, i as u16);
+        assert_eq!(pin_map[i].y, 0);
+    }
+    // "\n" maps to end of first line
+    assert_eq!(pin_map[5].node, node);
+    for i in 0..5 {
+        let idx = 6 + i;
+        assert_eq!(pin_map[idx].node, node);
+        assert_eq!(pin_map[idx].x, i as u16);
+        assert_eq!(pin_map[idx].y, 1);
+    }
+}
+
+#[test]
+fn terminal_formatter_vt_with_palette_and_pin_map() {
+    let mut t = term(80, 24);
+    feed(&mut t, b"\x1b]4;0;rgb:12/34/56\x1b\\");
+    feed(&mut t, b"test");
+
+    let mut pin_map = Vec::new();
+    let mut f = TerminalFormatter::new(&t, Options::vt());
+    f.pin_map = Some(&mut pin_map);
+    let output = f.format_string().unwrap();
+
+    // Palette bytes should be mapped to top left
+    assert_eq!(pin_map.len(), output.len());
+    let node = node_of_first(&t);
+    for p in &pin_map {
+        assert_eq!(p.node, node);
+    }
+}
+
+#[test]
+fn terminal_formatter_with_selection_and_pin_map() {
+    let mut t = term(80, 24);
+    feed(&mut t, b"line1\r\nline2\r\nline3");
+    let sel = line2_selection(&t);
+
+    let mut pin_map = Vec::new();
+    let mut f = TerminalFormatter::new(&t, Options::plain());
+    f.content = Content::Selection(Some(sel));
+    f.pin_map = Some(&mut pin_map);
+    let output = f.format_string().unwrap();
+    assert_eq!(output, "line2");
+
+    assert_eq!(pin_map.len(), output.len());
+    let node = node_of_first(&t);
+    for i in 0..5 {
+        assert_eq!(pin_map[i].node, node);
+        assert_eq!(pin_map[i].x, i as u16);
+        assert_eq!(pin_map[i].y, 1);
+    }
+}

crates/ghostty-terminal/src/formatter/tests/p3.rs

@@ -0,0 +1,530 @@
+use super::*;
+use ghostty_vt::modes::Mode;
+
+/// Format the screen with the given extras, returning output and pin map.
+fn screen_vt(t: &Terminal, mutate: impl FnOnce(&mut ScreenFormatter<'_>)) -> (String, Vec<Pin>) {
+    let mut pin_map: Vec<Pin> = Vec::new();
+    let out = {
+        let mut f = ScreenFormatter::new(t.screen(), Options::vt());
+        mutate(&mut f);
+        f.pin_map = Some(&mut pin_map);
+        f.format_string().unwrap()
+    };
+    (out, pin_map)
+}
+
+fn replay(output: &str) -> Terminal {
+    let mut t2 = term(80, 24);
+    feed(&mut t2, output.as_bytes());
+    t2
+}
+
+fn first_node(t: &Terminal) -> crate::page_list::NodeId {
+    t.screen().pages.first.unwrap()
+}
+
+fn page_fmt(t: &Terminal, opts: &Options) -> String {
+    PageFormatter::new(last_page(t), opts)
+        .format_string()
+        .unwrap()
+}
+
+const HTML_OPEN: &str = "<div style=\"font-family: monospace; white-space: pre;\">";
+
+#[test]
+fn screen_plain_single_line() {
+    let mut t = term(80, 24);
+    feed(&mut t, b"hello, world");
+
+    let mut pin_map = Vec::new();
+    let output = {
+        let mut f = ScreenFormatter::new(t.screen(), Options::plain());
+        f.pin_map = Some(&mut pin_map);
+        f.format_string().unwrap()
+    };
+    assert_eq!(output, "hello, world");
+
+    assert_eq!(output.len(), pin_map.len());
+    let node = first_node(&t);
+    for (i, p) in pin_map.iter().enumerate() {
+        assert_eq!(
+            *p,
+            Pin {
+                node,
+                x: i as u16,
+                y: 0,
+                garbage: false
+            }
+        );
+    }
+}
+
+#[test]
+fn screen_plain_multiline() {
+    let mut t = term(80, 24);
+    feed(&mut t, b"hello\r\nworld");
+
+    let mut pin_map = Vec::new();
+    let output = {
+        let mut f = ScreenFormatter::new(t.screen(), Options::plain());
+        f.pin_map = Some(&mut pin_map);
+        f.format_string().unwrap()
+    };
+    assert_eq!(output, "hello\nworld");
+
+    assert_eq!(output.len(), pin_map.len());
+    let node = first_node(&t);
+    for i in 0..5 {
+        assert_eq!(pin_map[i].node, node);
+        assert_eq!(pin_map[i].x, i as u16);
+        assert_eq!(pin_map[i].y, 0);
+    }
+    assert_eq!(pin_map[5].node, node);
+    for i in 0..5 {
+        let idx = 6 + i;
+        assert_eq!(pin_map[idx].node, node);
+        assert_eq!(pin_map[idx].x, i as u16);
+        assert_eq!(pin_map[idx].y, 1);
+    }
+}
+
+#[test]
+fn screen_plain_with_selection() {
+    let mut t = term(80, 24);
+    feed(&mut t, b"line1\r\nline2\r\nline3");
+
+    let pages = &t.screen().pages;
+    let a = pages.pin(Point::Active(Coordinate { x: 0, y: 1 })).unwrap();
+    let b = pages.pin(Point::Active(Coordinate { x: 4, y: 1 })).unwrap();
+
+    let mut pin_map = Vec::new();
+    let output = {
+        let mut f = ScreenFormatter::new(t.screen(), Options::plain());
+        f.content = Content::Selection(Some(Selection::new(a, b, false)));
+        f.pin_map = Some(&mut pin_map);
+        f.format_string().unwrap()
+    };
+    assert_eq!(output, "line2");
+
+    assert_eq!(output.len(), pin_map.len());
+    let node = first_node(&t);
+    for i in 0..5 {
+        assert_eq!(pin_map[i].node, node);
+        assert_eq!(pin_map[i].x, i as u16);
+        assert_eq!(pin_map[i].y, 1);
+    }
+}
+
+#[test]
+fn screen_vt_with_cursor_position() {
+    let mut t = term(80, 24);
+    feed(&mut t, b"hello\r\nworld");
+
+    let (output, pin_map) = screen_vt(&t, |f| f.extra.cursor = true);
+    let t2 = replay(&output);
+
+    assert_eq!(t.screen().cursor.x, t2.screen().cursor.x);
+    assert_eq!(t.screen().cursor.y, t2.screen().cursor.y);
+
+    assert_eq!(output.len(), pin_map.len());
+    let node = first_node(&t);
+    for p in &pin_map {
+        assert_eq!(p.node, node);
+    }
+}
+
+#[test]
+fn screen_vt_with_style() {
+    let mut t = term(80, 24);
+    feed(&mut t, b"\x1b[1;31mhello");
+
+    let (output, pin_map) = screen_vt(&t, |f| f.extra.style = true);
+    let t2 = replay(&output);
+
+    assert!(t.screen().cursor.style.eql(t2.screen().cursor.style));
+
+    assert_eq!(output.len(), pin_map.len());
+    let node = first_node(&t);
+    for p in &pin_map {
+        assert_eq!(p.node, node);
+    }
+}
+
+#[test]
+fn screen_vt_with_hyperlink() {
+    let mut t = term(80, 24);
+    feed(&mut t, b"\x1b]8;;http://example.com\x1b\\hello");
+
+    let (output, pin_map) = screen_vt(&t, |f| f.extra.hyperlink = true);
+    let t2 = replay(&output);
+
+    let l1 = &t.screen().cursor.hyperlink;
+    let l2 = &t2.screen().cursor.hyperlink;
+    assert_eq!(l1.is_some(), l2.is_some());
+    if let (Some(a), Some(b)) = (l1, l2) {
+        assert_eq!(a.uri, b.uri);
+    }
+
+    assert_eq!(output.len(), pin_map.len());
+    let node = first_node(&t);
+    for p in &pin_map {
+        assert_eq!(p.node, node);
+    }
+}
+
+#[test]
+fn screen_vt_with_protection() {
+    let mut t = term(80, 24);
+    feed(&mut t, b"\x1b[1\"qhello");
+
+    let (output, pin_map) = screen_vt(&t, |f| f.extra.protection = true);
+    let t2 = replay(&output);
+
+    assert_eq!(t.screen().cursor.protected, t2.screen().cursor.protected);
+
+    assert_eq!(output.len(), pin_map.len());
+    let node = first_node(&t);
+    for p in &pin_map {
+        assert_eq!(p.node, node);
+    }
+}
+
+#[test]
+fn screen_vt_with_kitty_keyboard() {
+    let mut t = term(80, 24);
+    // Set kitty keyboard flags (disambiguate + report_events = 3)
+    feed(&mut t, b"\x1b[=3;1uhello");
+
+    let (output, pin_map) = screen_vt(&t, |f| f.extra.kitty_keyboard = true);
+    let t2 = replay(&output);
+
+    let flags1 = t.screen().kitty_keyboard.current().int();
+    let flags2 = t2.screen().kitty_keyboard.current().int();
+    assert_eq!(flags1, flags2);
+
+    assert_eq!(output.len(), pin_map.len());
+    let node = first_node(&t);
+    for p in &pin_map {
+        assert_eq!(p.node, node);
+    }
+}
+
+#[test]
+fn screen_vt_with_charsets() {
+    use ghostty_vt::charsets::Slots;
+    let mut t = term(80, 24);
+    // Set G0 to DEC special and shift to G1
+    feed(&mut t, b"\x1b(0\x0ehello");
+
+    let (output, pin_map) = screen_vt(&t, |f| f.extra.charsets = true);
+    let t2 = replay(&output);
+
+    let (c1, c2) = (&t.screen().charset, &t2.screen().charset);
+    assert_eq!(c1.gl, c2.gl);
+    assert_eq!(c1.gr, c2.gr);
+    assert_eq!(c1.charsets.get(Slots::G0), c2.charsets.get(Slots::G0));
+
+    assert_eq!(output.len(), pin_map.len());
+    let node = first_node(&t);
+    for p in &pin_map {
+        assert_eq!(p.node, node);
+    }
+}
+
+fn term_vt(t: &Terminal, mutate: impl FnOnce(&mut TerminalFormatter<'_>)) -> String {
+    let mut f = TerminalFormatter::new(t, Options::vt());
+    mutate(&mut f);
+    f.format_string().unwrap()
+}
+
+#[test]
+fn terminal_vt_with_scrolling_region() {
+    let mut t = term(80, 24);
+    // Set scrolling region: top=5, bottom=20
+    feed(&mut t, b"\x1b[6;21rhello");
+
+    let output = term_vt(&t, |f| f.extra.scrolling_region = true);
+    let t2 = replay(&output);
+
+    assert_eq!(t.scrolling_region.top, t2.scrolling_region.top);
+    assert_eq!(t.scrolling_region.bottom, t2.scrolling_region.bottom);
+    assert_eq!(t.scrolling_region.left, t2.scrolling_region.left);
+    assert_eq!(t.scrolling_region.right, t2.scrolling_region.right);
+}
+
+#[test]
+fn terminal_vt_with_modes() {
+    let mut t = term(80, 24);
+    feed(&mut t, b"\x1b[?2004h"); // Bracketed paste
+    feed(&mut t, b"\x1b[?1000h"); // Mouse event normal
+    feed(&mut t, b"\x1b[?7l"); // Disable wraparound (default is true)
+    feed(&mut t, b"hello");
+
+    let output = term_vt(&t, |f| f.extra.modes = true);
+    let t2 = replay(&output);
+
+    for m in [
+        Mode::BracketedPaste,
+        Mode::MouseEventNormal,
+        Mode::Wraparound,
+    ] {
+        assert_eq!(t.modes.get(m), t2.modes.get(m));
+    }
+}
+
+#[test]
+fn terminal_vt_with_tabstops() {
+    let mut t = term(80, 24);
+    feed(&mut t, b"\x1b[3g"); // Clear all tabs
+    feed(&mut t, b"\x1b[5G\x1bH"); // Set tab at column 5
+    feed(&mut t, b"\x1b[15G\x1bH"); // Set tab at column 15
+    feed(&mut t, b"\x1b[30G\x1bH"); // Set tab at column 30
+    feed(&mut t, b"hello");
+
+    let output = term_vt(&t, |f| f.extra.tabstops = true);
+    let t2 = replay(&output);
+
+    for c in [4, 14, 29] {
+        assert_eq!(t.tabstops.get(c), t2.tabstops.get(c));
+        assert!(t2.tabstops.get(c));
+    }
+    assert!(!t2.tabstops.get(8)); // Not a tab
+}
+
+#[test]
+fn terminal_vt_with_keyboard_modes() {
+    let mut t = term(80, 24);
+    feed(&mut t, b"\x1b[>4;2m");
+    feed(&mut t, b"hello");
+
+    let output = term_vt(&t, |f| f.extra.keyboard = true);
+    let t2 = replay(&output);
+
+    assert_eq!(t.flags.modify_other_keys_2, t2.flags.modify_other_keys_2);
+    assert!(t2.flags.modify_other_keys_2);
+}
+
+#[test]
+fn terminal_vt_with_pwd() {
+    let mut t = term(80, 24);
+    feed(&mut t, b"\x1b]7;file://host/home/user\x1b\\hello");
+
+    let output = term_vt(&t, |f| f.extra.pwd = true);
+    let t2 = replay(&output);
+
+    assert_eq!(t.pwd, t2.pwd);
+}
+
+#[test]
+fn page_html_with_multiple_styles() {
+    let mut t = term(80, 24);
+    feed(&mut t, b"\x1b[1mbold\x1b[3mitalic\x1b[0mnormal");
+
+    let output = page_fmt(&t, &Options::html());
+    assert_eq!(
+        output,
+        "<div style=\"font-family: monospace; white-space: pre;\">\
+         <div style=\"display: inline;font-weight: bold;\">bold</div>\
+         <div style=\"display: inline;font-weight: bold;font-style: italic;\">italic</div>\
+         normal\
+         </div>"
+    );
+}
+
+#[test]
+fn page_html_plain_text() {
+    let mut t = term(80, 24);
+    feed(&mut t, b"hello, world");
+
+    let output = page_fmt(&t, &Options::html());
+    assert_eq!(output, format!("{HTML_OPEN}hello, world</div>"));
+}
+
+#[test]
+fn page_html_with_colors() {
+    let mut t = term(80, 24);
+    feed(&mut t, b"\x1b[31;44mcolored");
+
+    let output = page_fmt(&t, &Options::html());
+    assert_eq!(
+        output,
+        "<div style=\"font-family: monospace; white-space: pre;\">\
+         <div style=\"display: inline;color: var(--vt-palette-1);background-color: var(--vt-palette-4);\">colored</div>\
+         </div>"
+    );
+}
+
+#[test]
+fn terminal_formatter_html_with_palette() {
+    let mut t = term(80, 24);
+    feed(&mut t, b"\x1b]4;0;rgb:12/34/56\x1b\\");
+    feed(&mut t, b"\x1b]4;1;rgb:ab/cd/ef\x1b\\");
+    feed(&mut t, b"\x1b]4;255;rgb:ff/00/ff\x1b\\");
+    feed(&mut t, b"test");
+
+    let mut f = TerminalFormatter::new(&t, Options::html());
+    f.extra.palette = true;
+    let output = f.format_string().unwrap();
+
+    assert!(output.contains("<style>:root{"));
+    assert!(output.contains("--vt-palette-0: #123456;"));
+    assert!(output.contains("--vt-palette-1: #abcdef;"));
+    assert!(output.contains("--vt-palette-255: #ff00ff;"));
+    assert!(output.contains("}</style>"));
+    assert!(output.contains("test"));
+}
+
+#[test]
+fn page_html_with_background_and_foreground_colors() {
+    let mut t = term(80, 24);
+    feed(&mut t, b"hello");
+
+    let mut opts = Options::html();
+    opts.background = Some(Rgb {
+        r: 0x12,
+        g: 0x34,
+        b: 0x56,
+    });
+    opts.foreground = Some(Rgb {
+        r: 0xab,
+        g: 0xcd,
+        b: 0xef,
+    });
+    let output = page_fmt(&t, &opts);
+    assert_eq!(
+        output,
+        "<div style=\"font-family: monospace; white-space: pre;background-color: #123456;color: #abcdef;\">hello</div>"
+    );
+}
+
+#[test]
+fn page_html_with_escaping() {
+    let mut t = term(80, 24);
+    feed(&mut t, b"<tag>&\"'text");
+
+    let opts = Options::html();
+    let mut point_map: Vec<Coordinate> = Vec::new();
+    let output = {
+        let mut f = PageFormatter::new(last_page(&t), &opts);
+        f.point_map = Some(&mut point_map);
+        f.format_string().unwrap()
+    };
+    assert_eq!(
+        output,
+        format!("{HTML_OPEN}&lt;tag&gt;&amp;&quot;&#39;text</div>")
+    );
+
+    assert_eq!(output.len(), point_map.len());
+
+    let offset = HTML_OPEN.len();
+    for c in &point_map[..offset] {
+        assert_eq!(*c, Coordinate { x: 0, y: 0 });
+    }
+
+    let at = |i: usize, x: u16| {
+        assert_eq!(point_map[offset + i], Coordinate { x, y: 0 }, "index {i}");
+    };
+    for i in 0..4 {
+        at(i, 0);
+    }
+    at(4, 1);
+    at(5, 2);
+    at(6, 3);
+    for i in 0..4 {
+        at(7 + i, 4);
+    }
+    for i in 0..5 {
+        at(11 + i, 5);
+    }
+    for i in 0..6 {
+        at(16 + i, 6);
+    }
+    for i in 0..5 {
+        at(22 + i, 7);
+    }
+    at(27, 8);
+    at(28, 9);
+    at(29, 10);
+    at(30, 11);
+}
+
+#[test]
+fn page_html_with_unicode_as_numeric_entities() {
+    let mut t = term(80, 24);
+    feed(&mut t, "╰─ ❯".as_bytes());
+
+    let output = page_fmt(&t, &Options::html());
+    assert_eq!(output, format!("{HTML_OPEN}&#9584;&#9472; &#10095;</div>"));
+}
+
+#[test]
+fn page_html_ascii_characters_unchanged() {
+    let mut t = term(80, 24);
+    feed(&mut t, b"hello world");
+
+    let output = page_fmt(&t, &Options::html());
+    assert_eq!(output, format!("{HTML_OPEN}hello world</div>"));
+}
+
+#[test]
+fn page_html_mixed_ascii_and_unicode() {
+    let mut t = term(80, 24);
+    feed(&mut t, "test ╰─❯ ok".as_bytes());
+
+    let output = page_fmt(&t, &Options::html());
+    assert_eq!(
+        output,
+        format!("{HTML_OPEN}test &#9584;&#9472;&#10095; ok</div>")
+    );
+}
+
+#[test]
+fn page_vt_with_palette_option_emits_rgb() {
+    let mut t = term(80, 24);
+    feed(&mut t, b"\x1b]4;1;rgb:ab/cd/ef\x1b\\");
+    feed(&mut t, b"\x1b[31mred");
+
+    // Without palette option - should emit palette index
+    let output = page_fmt(&t, &Options::vt());
+    assert_eq!(output, "\x1b[0m\x1b[38;5;1mred\x1b[0m");
+
+    // With palette option - should emit RGB directly
+    let mut opts = Options::vt();
+    opts.palette = Some(t.colors.palette.current);
+    let output = page_fmt(&t, &opts);
+    assert_eq!(output, "\x1b[0m\x1b[38;2;171;205;239mred\x1b[0m");
+}
+
+#[test]
+fn page_html_with_palette_option_emits_rgb() {
+    let mut t = term(80, 24);
+    feed(&mut t, b"\x1b]4;1;rgb:ab/cd/ef\x1b\\");
+    feed(&mut t, b"\x1b[31mred");
+
+    let output = page_fmt(&t, &Options::html());
+    assert_eq!(
+        output,
+        "<div style=\"font-family: monospace; white-space: pre;\">\
+         <div style=\"display: inline;color: var(--vt-palette-1);\">red</div>\
+         </div>"
+    );
+
+    let mut opts = Options::html();
+    opts.palette = Some(t.colors.palette.current);
+    let output = page_fmt(&t, &opts);
+    assert_eq!(
+        output,
+        "<div style=\"font-family: monospace; white-space: pre;\">\
+         <div style=\"display: inline;color: rgb(171, 205, 239);\">red</div>\
+         </div>"
+    );
+}
+
+#[test]
+fn page_vt_style_reset_properly_closes_styles() {
+    let mut t = term(80, 24);
+    feed(&mut t, b"\x1b[1mbold\x1b[0mnormal");
+
+    let output = page_fmt(&t, &Options::vt());
+    assert_eq!(output, "\x1b[0m\x1b[1mbold\x1b[0mnormal");
+}

crates/ghostty-terminal/src/formatter/tests/p4.rs

@@ -0,0 +1,327 @@
+use super::*;
+
+fn map_entry(range: (char, char), replacement: Replacement) -> CodepointMap {
+    CodepointMap {
+        range: [range.0 as u32, range.1 as u32],
+        replacement,
+    }
+}
+
+/// Format the last page of `t` with `opts`, optionally collecting a point map.
+fn run(t: &Terminal, opts: &Options, point_map: Option<&mut Vec<Coordinate>>) -> String {
+    let mut f = PageFormatter::new(last_page(t), opts);
+    f.point_map = point_map;
+    f.format_string().unwrap()
+}
+
+fn plain_with_map(entries: Vec<CodepointMap>) -> Options {
+    let mut opts = Options::plain();
+    opts.codepoint_map = Some(entries);
+    opts
+}
+
+fn c(x: u16, y: u32) -> Coordinate {
+    Coordinate { x, y }
+}
+
+#[test]
+fn page_codepoint_map_single_replacement() {
+    let mut t = term(80, 24);
+    feed(&mut t, b"hello world");
+
+    // Replace 'o' with 'x'
+    let opts = plain_with_map(vec![map_entry(
+        ('o', 'o'),
+        Replacement::Codepoint('x' as u32),
+    )]);
+    let mut point_map = Vec::new();
+    let output = run(&t, &opts, Some(&mut point_map));
+    assert_eq!(output, "hellx wxrld");
+
+    // Verify point map - each output byte should map to original cell position
+    assert_eq!(output.len(), point_map.len());
+    for (i, coord) in point_map.iter().enumerate() {
+        assert_eq!(*coord, c(i as u16, 0));
+    }
+}
+
+#[test]
+fn page_codepoint_map_conflicting_replacement_prefers_last() {
+    let mut t = term(80, 24);
+    feed(&mut t, b"hello");
+
+    // Replace 'o' with 'x', then with 'y' - should prefer last
+    let opts = plain_with_map(vec![
+        map_entry(('o', 'o'), Replacement::Codepoint('x' as u32)),
+        map_entry(('o', 'o'), Replacement::Codepoint('y' as u32)),
+    ]);
+    assert_eq!(run(&t, &opts, None), "helly");
+}
+
+#[test]
+fn page_codepoint_map_replace_with_string() {
+    let mut t = term(80, 24);
+    feed(&mut t, b"hello");
+
+    // Replace 'o' with a multi-byte string
+    let opts = plain_with_map(vec![map_entry(
+        ('o', 'o'),
+        Replacement::String("XYZ".into()),
+    )]);
+    let mut point_map = Vec::new();
+    let output = run(&t, &opts, Some(&mut point_map));
+    assert_eq!(output, "hellXYZ");
+
+    // Verify point map - string replacements should all map to the original cell
+    assert_eq!(output.len(), point_map.len());
+    for i in 0..4 {
+        assert_eq!(point_map[i], c(i as u16, 0));
+    }
+    // All bytes of the replacement string "XYZ" should point to position 4 (where 'o' was)
+    assert_eq!(point_map[4], c(4, 0)); // X
+    assert_eq!(point_map[5], c(4, 0)); // Y
+    assert_eq!(point_map[6], c(4, 0)); // Z
+}
+
+#[test]
+fn page_codepoint_map_range_replacement() {
+    let mut t = term(80, 24);
+    feed(&mut t, b"abcdefg");
+
+    // Replace 'b' through 'e' with 'X'
+    let opts = plain_with_map(vec![map_entry(
+        ('b', 'e'),
+        Replacement::Codepoint('X' as u32),
+    )]);
+    assert_eq!(run(&t, &opts, None), "aXXXXfg");
+}
+
+#[test]
+fn page_codepoint_map_multiple_ranges() {
+    let mut t = term(80, 24);
+    feed(&mut t, b"hello world");
+
+    // Replace 'a'-'m' with 'A' and 'n'-'z' with 'Z'
+    let opts = plain_with_map(vec![
+        map_entry(('a', 'm'), Replacement::Codepoint('A' as u32)),
+        map_entry(('n', 'z'), Replacement::Codepoint('Z' as u32)),
+    ]);
+    // h e l l o   w o r l d
+    // A A A A Z   Z Z Z A A
+    assert_eq!(run(&t, &opts, None), "AAAAZ ZZZAA");
+}
+
+#[test]
+fn page_codepoint_map_unicode_replacement() {
+    let mut t = term(80, 24);
+    feed(&mut t, "hello \u{26A1} world".as_bytes());
+
+    // Replace lightning bolt with fire emoji
+    let opts = plain_with_map(vec![map_entry(
+        ('\u{26A1}', '\u{26A1}'),
+        Replacement::String("\u{1F525}".into()),
+    )]);
+    let mut point_map = Vec::new();
+    let output = run(&t, &opts, Some(&mut point_map));
+    assert_eq!(output, "hello \u{1F525} world");
+
+    // Verify point map
+    assert_eq!(output.len(), point_map.len());
+    // Note: the bolt is a wide character occupying cells 6-7
+    for i in 0..6 {
+        assert_eq!(point_map[i], c(i as u16, 0));
+    }
+    // The fire emoji is 4 UTF-8 bytes, all should map to cell 6 (where the bolt was)
+    let fire_start = 6; // "hello " is 6 bytes
+    for i in 0..4 {
+        assert_eq!(point_map[fire_start + i], c(6, 0));
+    }
+    // " world" follows
+    let world_start = fire_start + 4;
+    for i in 0..6 {
+        assert_eq!(point_map[world_start + i], c(8 + i as u16, 0));
+    }
+}
+
+#[test]
+fn page_codepoint_map_with_styled_formats() {
+    let mut t = term(10, 24);
+    feed(&mut t, b"\x1b[31mred text\x1b[0m");
+
+    // Replace 'e' with 'X' in styled text
+    let mut opts = Options::vt();
+    opts.codepoint_map = Some(vec![map_entry(
+        ('e', 'e'),
+        Replacement::Codepoint('X' as u32),
+    )]);
+    // Should preserve styles while replacing text
+    // "red text" becomes "rXd tXxt"
+    // VT format uses \x1b[38;5;1m for palette color 1
+    assert_eq!(run(&t, &opts, None), "\x1b[0m\x1b[38;5;1mrXd tXxt\x1b[0m");
+}
+
+#[test]
+fn page_codepoint_map_empty_map() {
+    let mut t = term(80, 24);
+    feed(&mut t, b"hello world");
+
+    // Empty map should not change anything
+    let opts = plain_with_map(Vec::new());
+    assert_eq!(run(&t, &opts, None), "hello world");
+
+    // A None map is equivalent.
+    let mut opts = Options::plain();
+    opts.codepoint_map = None;
+    assert_eq!(run(&t, &opts, None), "hello world");
+}
+
+#[test]
+fn page_vt_background_color_on_trailing_blank_cells() {
+    // This test reproduces a bug where trailing cells with background color
+    // but no text are emitted as plain spaces without SGR sequences.
+    // This causes TUIs like htop to lose background colors on rehydration.
+    let mut t = term(20, 5);
+
+    // Simulate a TUI row: "CPU:" with text, then trailing cells with red background
+    // to end of line (no text after the colored region).
+    // \x1b[41m sets red background, then EL fills rest of row with that bg.
+    feed(&mut t, b"CPU:\x1b[41m\x1b[K");
+    // Reset colors and move to next line with different content
+    feed(&mut t, b"\x1b[0m\r\nline2");
+
+    let mut opts = Options::vt();
+    opts.trim = false; // Don't trim so we can see the trailing behavior
+    let output = run(&t, &opts, None);
+
+    // The output should preserve the red background SGR for trailing cells on line 1.
+    // The red background should appear BEFORE the newline, not after.
+
+    // Find position of CRLF
+    let crlf_pos = output.find("\r\n").expect("crlf");
+
+    // Check that red background (48;5;1) appears BEFORE the newline (on line 1)
+    let line1 = &output[..crlf_pos];
+    let has_red_bg_line1 = line1.contains("\x1b[41m") || line1.contains("\x1b[48;5;1m");
+    assert!(has_red_bg_line1);
+}
+
+const HTML_OPEN: &str = "<div style=\"font-family: monospace; white-space: pre;\">";
+
+fn html(t: &Terminal, point_map: Option<&mut Vec<Coordinate>>) -> String {
+    run(t, &Options::html(), point_map)
+}
+
+#[test]
+fn page_html_with_hyperlinks() {
+    let mut t = term(80, 24);
+
+    // Start a hyperlink, write some text, end it
+    feed(
+        &mut t,
+        b"\x1b]8;;https://example.com\x1b\\link text\x1b]8;;\x1b\\ normal",
+    );
+
+    assert_eq!(
+        html(&t, None),
+        format!("{HTML_OPEN}<a href=\"https://example.com\">link text</a> normal</div>")
+    );
+}
+
+#[test]
+fn page_html_with_multiple_hyperlinks() {
+    let mut t = term(80, 24);
+
+    // Two different hyperlinks
+    feed(
+        &mut t,
+        b"\x1b]8;;https://first.com\x1b\\first\x1b]8;;\x1b\\ ",
+    );
+    feed(
+        &mut t,
+        b"\x1b]8;;https://second.com\x1b\\second\x1b]8;;\x1b\\",
+    );
+
+    assert_eq!(
+        html(&t, None),
+        format!(
+            "{HTML_OPEN}<a href=\"https://first.com\">first</a> <a href=\"https://second.com\">second</a></div>"
+        )
+    );
+}
+
+#[test]
+fn page_html_with_hyperlink_escaping() {
+    let mut t = term(80, 24);
+
+    // URL with special characters that need escaping
+    feed(
+        &mut t,
+        b"\x1b]8;;https://example.com?a=1&b=2\x1b\\link\x1b]8;;\x1b\\",
+    );
+
+    assert_eq!(
+        html(&t, None),
+        format!("{HTML_OPEN}<a href=\"https://example.com?a=1&amp;b=2\">link</a></div>")
+    );
+}
+
+#[test]
+fn page_html_with_styled_hyperlink() {
+    let mut t = term(80, 24);
+
+    // Bold hyperlink
+    feed(
+        &mut t,
+        b"\x1b]8;;https://example.com\x1b\\\x1b[1mbold link\x1b[0m\x1b]8;;\x1b\\",
+    );
+
+    assert_eq!(
+        html(&t, None),
+        format!(
+            "{HTML_OPEN}<div style=\"display: inline;font-weight: bold;\"><a href=\"https://example.com\">bold link</div></a></div>"
+        )
+    );
+}
+
+#[test]
+fn page_html_hyperlink_closes_style_before_anchor() {
+    let mut t = term(80, 24);
+
+    // Styled hyperlink followed by plain text
+    feed(
+        &mut t,
+        b"\x1b]8;;https://example.com\x1b\\\x1b[1mbold\x1b[0m plain",
+    );
+
+    assert_eq!(
+        html(&t, None),
+        format!(
+            "{HTML_OPEN}<div style=\"display: inline;font-weight: bold;\"><a href=\"https://example.com\">bold</div> plain</a></div>"
+        )
+    );
+}
+
+#[test]
+fn page_html_hyperlink_point_map_maps_closing_to_previous_cell() {
+    let mut t = term(80, 24);
+
+    feed(
+        &mut t,
+        b"\x1b]8;;https://example.com\x1b\\link\x1b]8;;\x1b\\ normal",
+    );
+
+    let mut point_map = Vec::new();
+    let output = html(&t, Some(&mut point_map));
+
+    let expected_output =
+        format!("{HTML_OPEN}<a href=\"https://example.com\">link</a> normal</div>");
+    assert_eq!(output, expected_output);
+    assert_eq!(expected_output.len(), point_map.len());
+
+    // The </a> closing tag bytes should all map to the last cell of the link
+    let closing_idx = expected_output.find("</a>").unwrap();
+    let expected_coord = point_map[closing_idx - 1];
+    for i in closing_idx..closing_idx + "</a>".len() {
+        assert_eq!(point_map[i], expected_coord);
+    }
+}

crates/ghostty-terminal/src/highlight.rs

@@ -0,0 +1,228 @@
+//! Highlights are any contiguous sequences of cells that should
+//! be called out in some way, most commonly for text selection but
+//! also search results or any other purpose.
+//!
+//! Within the terminal package, a highlight is a generic concept
+//! that represents a range of cells.
+//!
+//! Port of `ZIG/src/terminal/highlight.zig`.
+
+// NOTE: The plan is for highlights to ultimately replace Selection
+// completely. Selection is deeply tied to various parts of the Ghostty
+// internals so this may take some time.
+
+use crate::{
+    page::Error,
+    page_list::{NodeId, PageList, Pin, TrackedPin},
+    screen::Screen,
+    size,
+};
+
+/// An untracked highlight is a highlight that stores its highlighted
+/// area as a top-left and bottom-right screen pin. Since it is untracked,
+/// the pins are only valid for the current terminal state and may not
+/// be safe to use after any terminal modifications.
+///
+/// For rectangle highlights/selections, the downstream consumer of this
+/// code is expected to interpret the pins in whatever shape they want.
+/// For example, a rectangular selection would interpret the pins as
+/// setting the x bounds for each row between start.y and end.y.
+///
+/// To simplify all operations, start MUST be before or equal to end.
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub struct Untracked {
+    pub start: Pin,
+    pub end: Pin,
+}
+
+impl Untracked {
+    pub fn track(&self, screen: &mut Screen) -> Result<Tracked, Error> {
+        Tracked::init(screen, self.start, self.end)
+    }
+
+    pub fn eql(self, other: Untracked) -> bool {
+        self.start.eql(other.start) && self.end.eql(other.end)
+    }
+}
+
+/// A tracked highlight is a highlight that stores its highlighted
+/// area as tracked pins within a screen.
+///
+/// A tracked highlight ensures that the pins remain valid even as
+/// the terminal state changes. Because of this, tracked highlights
+/// have more operations available to them.
+///
+/// There is more overhead to creating and maintaining tracked highlights.
+/// If you're manipulating highlights that are untracked and you're sure
+/// that the terminal state won't change, you can use the `init_assume`
+/// function.
+///
+/// Unlike Zig (which stores `*Pin`), the tracked pins are handles into the
+/// owning [`PageList`]; read them with `pages.tracked_pin(h.start)`.
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub struct Tracked {
+    pub start: TrackedPin,
+    pub end: TrackedPin,
+}
+
+impl Tracked {
+    pub fn init(screen: &mut Screen, start: Pin, end: Pin) -> Result<Tracked, Error> {
+        let start_tracked = screen.pages.track_pin(start)?;
+        let end_tracked = match screen.pages.track_pin(end) {
+            Ok(v) => v,
+            Err(e) => {
+                screen.pages.untrack_pin(start_tracked);
+                return Err(e);
+            }
+        };
+        Ok(Tracked {
+            start: start_tracked,
+            end: end_tracked,
+        })
+    }
+
+    /// Initializes a tracked highlight by assuming that the provided
+    /// pins are already tracked. This allows callers to perform tracked
+    /// operations without the overhead of tracking the pins, if the
+    /// caller can guarantee that the pins are already tracked or that
+    /// the terminal state will not change.
+    ///
+    /// Do not call deinit on highlights created with this function.
+    pub fn init_assume(start: TrackedPin, end: TrackedPin) -> Tracked {
+        Tracked { start, end }
+    }
+
+    pub fn deinit(self, screen: &mut Screen) {
+        screen.pages.untrack_pin(self.start);
+        screen.pages.untrack_pin(self.end);
+    }
+
+    /// Current (untracked) value of the highlight.
+    pub fn untracked(&self, pages: &PageList) -> Option<Untracked> {
+        Some(Untracked {
+            start: pages.tracked_pin(self.start)?,
+            end: pages.tracked_pin(self.end)?,
+        })
+    }
+}
+
+/// A flattened highlight is a highlight that stores its highlighted
+/// area as a list of page chunks. This representation allows for
+/// traversing the entire highlighted area without needing to read any
+/// terminal state or dereference any page nodes (which may have been
+/// pruned).
+#[derive(Debug, Clone, PartialEq, Eq, Default)]
+pub struct Flattened {
+    /// The page chunks that make up this highlight. This handles the
+    /// y bounds since chunks[0].start is the first highlighted row
+    /// and chunks[len - 1].end is the last highlighted row (exclusive).
+    pub chunks: Vec<Chunk>,
+
+    /// The x bounds of the highlight. `bot_x` may be less than `top_x`
+    /// for typical left-to-right highlights: can start the selection right
+    /// of the end on a higher row.
+    pub top_x: size::CellCountInt,
+    pub bot_x: size::CellCountInt,
+}
+
+/// A flattened chunk is almost identical to a PageList.Chunk but
+/// we also flatten the serial number. This lets the flattened
+/// highlight more robust for comparisons and validity checks with
+/// the PageList.
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub struct Chunk {
+    pub node: NodeId,
+    pub serial: u64,
+    pub start: size::CellCountInt,
+    pub end: size::CellCountInt,
+}
+
+impl Flattened {
+    pub const EMPTY: Flattened = Flattened {
+        chunks: Vec::new(),
+        top_x: 0,
+        bot_x: 0,
+    };
+
+    pub fn empty() -> Flattened {
+        Self::EMPTY
+    }
+
+    pub fn init(pages: &PageList, start: Pin, end: Pin) -> Result<Flattened, Error> {
+        let mut result = Vec::new();
+        for chunk in pin_page_iterator(pages, start, end) {
+            let serial = pages
+                .node(chunk.node)
+                .ok_or(Error::InvalidCoordinate)?
+                .serial;
+            result.push(Chunk {
+                node: chunk.node,
+                serial,
+                start: chunk.start,
+                end: chunk.end,
+            });
+        }
+        // NOTE: The Zig code assigns `.end_x = end.x` here (a typo for
+        // `bot_x`, never compiled since the function is unused).
+        Ok(Flattened {
+            chunks: result,
+            top_x: start.x,
+            bot_x: end.x,
+        })
+    }
+
+    pub fn start_pin(&self) -> Pin {
+        let first = self.chunks[0];
+        Pin {
+            node: first.node,
+            x: self.top_x,
+            y: first.start,
+            garbage: false,
+        }
+    }
+
+    pub fn end_pin(&self) -> Pin {
+        let last = self.chunks[self.chunks.len() - 1];
+        Pin {
+            node: last.node,
+            x: self.bot_x,
+            y: last.end - 1,
+            garbage: false,
+        }
+    }
+
+    /// Convert to an Untracked highlight.
+    pub fn untracked(&self) -> Untracked {
+        Untracked {
+            start: self.start_pin(),
+            end: self.end_pin(),
+        }
+    }
+}
+
+/// Equivalent of Zig `Pin.pageIterator(.right_down, limit)`: iterate the
+/// page chunks (inclusive of `end`'s row) starting at `start`.
+///
+/// Like Zig this does not validate the pins against the page sizes (the end
+/// row of the last chunk is `end.y + 1` even if the page is smaller), so
+/// consumers must clamp.
+pub fn pin_page_iterator(
+    pages: &PageList,
+    start: Pin,
+    end: Pin,
+) -> impl Iterator<Item = crate::page_list::Chunk> + '_ {
+    let mut cur = Some(start.node);
+    std::iter::from_fn(move || {
+        let node = cur?;
+        let n = pages.node(node)?;
+        let first = node == start.node;
+        let last = node == end.node;
+        let chunk = crate::page_list::Chunk {
+            node,
+            start: if first { start.y } else { 0 },
+            end: if last { end.y + 1 } else { n.data.size.rows },
+        };
+        cur = if last { None } else { n.next };
+        Some(chunk)
+    })
+}

crates/ghostty-terminal/src/lib.rs

@@ -1,12 +1,15 @@
 //! Safe page-based terminal memory model.
 #![cfg_attr(test, allow(clippy::unwrap_used))]
 pub mod cursor;
+pub mod formatter;
+pub mod highlight;
 pub mod hyperlink;
 pub mod page;
 pub mod page_list;
 pub mod pin_iter;
 pub mod point;
 pub mod ref_counted_set;
+pub mod render;
 pub mod screen;
 pub mod screen_set;
 pub mod selection;

crates/ghostty-terminal/src/render.rs

@@ -0,0 +1,1390 @@
+//! Render state: a snapshot of the terminal state required to render a frame.
+//!
+//! Port of `ZIG/src/terminal/render.zig`.
+//!
+//! Developer note: this is in the terminal crate and not the renderer crate
+//! because the goal is that this remains generic to multiple renderers.
+//!
+//! Contains the state required to render the screen, including optimizing
+//! for repeated render calls and only rendering dirty regions.
+//!
+//! Previously, our renderer would use `clone` to clone the screen within
+//! the viewport to perform rendering. This worked well enough that we kept
+//! it all the way up through the Ghostty 1.2.x series, but the clone time
+//! was repeatedly a bottleneck blocking IO.
+//!
+//! Rather than a generic clone that tries to clone all screen state per call
+//! (within a region), a stateful approach that optimizes for only what a
+//! renderer needs to do makes more sense.
+//!
+//! To use this, initialize the render state to empty, then call `update`
+//! on each frame to update the state to the latest terminal state.
+//!
+//! ```ignore
+//! let mut state = RenderState::new();
+//! state.update(&mut terminal)?;
+//! ```
+//!
+//! Note: the render state retains as much memory as possible between updates
+//! to prevent future allocations. If a very large frame is rendered once,
+//! the render state will retain that much memory until dropped. To avoid
+//! waste, it is recommended that the caller drop and start with an
+//! empty render state every so often.
+
+use crate::{
+    cursor,
+    highlight::Flattened,
+    page::{self, ContentTag, Error, Wide},
+    page_list::{Direction, PageList, Pin},
+    point::{Coordinate, Point, Tag},
+    screen_set::Key as ScreenKey,
+    selection::Selection,
+    size,
+    style::{Color, Style},
+    terminal::{Dirty as TerminalDirty, Terminal},
+};
+use ghostty_vt::{
+    color::{self, Palette, Rgb},
+    modes::Mode,
+};
+use std::collections::HashSet;
+
+/// Contains the state required to render the screen. See the module docs.
+#[derive(Debug, Clone)]
+pub struct RenderState {
+    /// The current screen dimensions. It is possible that these don't match
+    /// the renderer's current dimensions in grid cells because resizing
+    /// can happen asynchronously. This can lead to a one or two frame
+    /// mismatch a renderer needs to handle.
+    ///
+    /// The viewport is always exactly equal to the active area size so this
+    /// is also the viewport size.
+    pub rows: size::CellCountInt,
+    pub cols: size::CellCountInt,
+
+    /// The color state for the terminal.
+    pub colors: Colors,
+
+    /// Cursor state within the viewport.
+    pub cursor: Cursor,
+
+    /// The rows (y=0 is top) of the viewport. Guaranteed to be `rows` length.
+    pub row_data: Vec<Row>,
+
+    /// The dirty state of the render state. This is set by the update method.
+    /// The renderer/caller should set this to false when it has handled
+    /// the dirty state.
+    pub dirty: Dirty,
+
+    /// The screen type that this state represents. This is used primarily
+    /// to detect changes.
+    pub screen: ScreenKey,
+
+    /// The last viewport pin used to generate this state. This is NOT
+    /// a tracked pin and is generally NOT safe to read other than the direct
+    /// values for comparison.
+    pub viewport_pin: Option<Pin>,
+
+    /// The cached selection so we can avoid expensive selection calculations
+    /// if possible.
+    selection_cache: Option<SelectionCache>,
+}
+
+/// The color state for the terminal.
+///
+/// The background/foreground will be reversed if the terminal reverse
+/// color mode is on! You do not need to handle that manually!
+#[derive(Debug, Clone, Copy)]
+pub struct Colors {
+    pub background: Rgb,
+    pub foreground: Rgb,
+    pub cursor: Option<Rgb>,
+    pub palette: Palette,
+}
+
+#[derive(Debug, Clone, Copy)]
+pub struct Cursor {
+    /// The x/y position of the cursor within the active area.
+    pub active: Coordinate,
+
+    /// The x/y position of the cursor within the viewport. This
+    /// may be None if the cursor is not visible within the viewport.
+    pub viewport: Option<CursorViewport>,
+
+    /// The cell data for the cursor position. Managed memory is not
+    /// safe to access from this.
+    pub cell: page::Cell,
+
+    /// The style, always valid even if the cell is default style.
+    pub style: Style,
+
+    /// The visual style of the cursor itself, such as a block or bar.
+    pub visual_style: cursor::Style,
+
+    /// True if the cursor is detected to be at a password input field.
+    pub password_input: bool,
+
+    /// Cursor visibility state determined by the terminal mode.
+    pub visible: bool,
+
+    /// Cursor blink state determined by the terminal mode.
+    pub blinking: bool,
+}
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub struct CursorViewport {
+    /// The x/y position of the cursor within the viewport.
+    pub x: size::CellCountInt,
+    pub y: size::CellCountInt,
+
+    /// Whether the cursor is part of a wide character and
+    /// on the tail of it. If so, some renderers may use this
+    /// to move the cursor back one.
+    pub wide_tail: bool,
+}
+
+/// A row within the viewport.
+#[derive(Debug, Clone)]
+pub struct Row {
+    /// The page pin. This is not safe to read unless you can guarantee
+    /// the terminal state hasn't changed since the last `update` call.
+    pub pin: Pin,
+
+    /// Raw row data.
+    pub raw: page::Row,
+
+    /// The cells in this row. Guaranteed to be `cols` length.
+    pub cells: Cells,
+
+    /// A dirty flag that can be used by the renderer to track
+    /// its own draw state. `update` will mark this true whenever
+    /// this row is changed, too.
+    pub dirty: bool,
+
+    /// The x range of the selection within this row.
+    pub selection: Option<[size::CellCountInt; 2]>,
+
+    /// The highlights within this row.
+    pub highlights: Vec<Highlight>,
+}
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub struct Highlight {
+    /// A special tag that can be used by the caller to differentiate
+    /// different highlight types. The value is opaque to the RenderState.
+    pub tag: u8,
+
+    /// The x ranges of highlights within this row.
+    pub range: [size::CellCountInt; 2],
+}
+
+/// One cell of a row (the Zig `RenderState.Cell`), by reference.
+#[derive(Debug, Clone, Copy)]
+pub struct Cell<'a> {
+    /// Always set, this is the raw copied cell data from page.Cell.
+    /// The managed memory (hyperlinks, graphemes, etc.) is NOT safe
+    /// to access from here. It is duplicated into the other fields if
+    /// it exists.
+    pub raw: page::Cell,
+
+    /// Grapheme data for the cell (the codepoints after the first). Empty
+    /// unless the raw cell's content_tag is `CodepointGrapheme`.
+    pub grapheme: &'a [u32],
+
+    /// The style data for the cell. The default style unless the style_id
+    /// is non-default on raw (or the cell is a bg-color-only cell).
+    pub style: Style,
+}
+
+/// The cells of a row, stored as a struct of arrays (the Zig
+/// `MultiArrayList(Cell)`) so that the common plain-text case only copies the
+/// raw cells.
+///
+/// `raw` always has exactly `cols` entries. `grapheme` and `style` either
+/// have exactly `cols` entries, or are empty when the source row has no
+/// managed memory (in which case every cell has no grapheme and the default
+/// style). Always use the accessors rather than indexing those two directly.
+#[derive(Debug, Clone, Default)]
+pub struct Cells {
+    pub raw: Vec<page::Cell>,
+    pub grapheme: Vec<Vec<u32>>,
+    pub style: Vec<Style>,
+}
+
+impl Cells {
+    pub fn len(&self) -> usize {
+        self.raw.len()
+    }
+
+    pub fn is_empty(&self) -> bool {
+        self.raw.is_empty()
+    }
+
+    /// The grapheme (extra codepoints) of the cell at `x`.
+    pub fn grapheme(&self, x: usize) -> &[u32] {
+        self.grapheme.get(x).map_or(&[], Vec::as_slice)
+    }
+
+    /// The style of the cell at `x` (default style if none).
+    pub fn style(&self, x: usize) -> Style {
+        self.style.get(x).copied().unwrap_or_default()
+    }
+
+    /// The full cell at `x`. Panics if out of range.
+    pub fn get(&self, x: usize) -> Cell<'_> {
+        Cell {
+            raw: self.raw[x],
+            grapheme: self.grapheme(x),
+            style: self.style(x),
+        }
+    }
+
+    /// Iterate all cells in order.
+    pub fn iter(&self) -> impl Iterator<Item = Cell<'_>> + '_ {
+        (0..self.raw.len()).map(|x| self.get(x))
+    }
+
+    fn clear(&mut self) {
+        self.raw.clear();
+        self.grapheme.clear();
+        self.style.clear();
+    }
+}
+
+/// Dirty state
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Default)]
+pub enum Dirty {
+    /// Not dirty at all. Can skip rendering if prior state was
+    /// already rendered.
+    #[default]
+    False,
+
+    /// Partially dirty. Some rows changed but not all. None of the
+    /// global state changed such as colors.
+    Partial,
+
+    /// Fully dirty. Global state changed or dimensions changed. All rows
+    /// should be redrawn.
+    Full,
+}
+
+#[derive(Debug, Clone, Copy)]
+struct SelectionCache {
+    selection: Selection,
+    tl_pin: Pin,
+    br_pin: Pin,
+}
+
+impl Default for RenderState {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
+impl RenderState {
+    /// Initial (empty) state.
+    pub fn new() -> RenderState {
+        RenderState {
+            rows: 0,
+            cols: 0,
+            colors: Colors {
+                background: Rgb::default(),
+                foreground: Rgb::default(),
+                cursor: None,
+                palette: color::DEFAULT,
+            },
+            cursor: Cursor {
+                active: Coordinate { x: 0, y: 0 },
+                viewport: None,
+                cell: page::Cell::default(),
+                style: Style::default(),
+                visual_style: cursor::Style::Block,
+                password_input: false,
+                visible: true,
+                blinking: false,
+            },
+            row_data: Vec::new(),
+            dirty: Dirty::False,
+            screen: ScreenKey::Primary,
+            viewport_pin: None,
+            selection_cache: None,
+        }
+    }
+
+    /// Update the render state to the latest terminal state.
+    ///
+    /// This will reset the terminal dirty state since it is consumed
+    /// by this render state update.
+    pub fn update(&mut self, t: &mut Terminal) -> Result<(), Error> {
+        let active_key = t.screens.active_key;
+        let terminal_dirty = t.flags.dirty != TerminalDirty::default();
+        let s = t.screens.active_mut();
+        let viewport_pin = s
+            .pages
+            .get_top_left(Tag::Viewport)
+            .ok_or(Error::InvalidCoordinate)?;
+        let redraw = 'redraw: {
+            // If our screen key changed, we need to do a full rebuild
+            // because our render state is viewport-specific.
+            if active_key != self.screen {
+                break 'redraw true;
+            }
+
+            // If our terminal is dirty at all, we do a full rebuild. These
+            // dirty values are full-terminal dirty values.
+            if terminal_dirty {
+                break 'redraw true;
+            }
+
+            // If our screen is dirty at all, we do a full rebuild. This is
+            // a full screen dirty tracker.
+            if s.dirty != crate::screen::Dirty::default() {
+                break 'redraw true;
+            }
+
+            // If our dimensions changed, we do a full rebuild.
+            if self.rows != s.pages.rows || self.cols != s.pages.cols {
+                break 'redraw true;
+            }
+
+            // If our viewport pin changed, we do a full rebuild.
+            if let Some(old) = self.viewport_pin
+                && !old.eql(viewport_pin)
+            {
+                break 'redraw true;
+            }
+
+            false
+        };
+
+        // Always set our cheap fields, its more expensive to compare
+        self.rows = s.pages.rows;
+        self.cols = s.pages.cols;
+        self.viewport_pin = Some(viewport_pin);
+        self.cursor.active = Coordinate {
+            x: s.cursor.x,
+            y: u32::from(s.cursor.y),
+        };
+        self.cursor.cell = s.cursor_cell();
+        self.cursor.style = s.cursor.style;
+        self.cursor.visual_style = s.cursor.cursor_style;
+        self.cursor.password_input = t.flags.password_input;
+        self.cursor.visible = t.modes.get(Mode::CursorVisible);
+        self.cursor.blinking = t.modes.get(Mode::CursorBlinking);
+
+        // Always reset the cursor viewport position. In the future we can
+        // probably cache this by comparing the cursor pin and viewport pin
+        // but may not be worth it.
+        self.cursor.viewport = None;
+
+        // Colors.
+        self.colors.cursor = t.colors.cursor.get();
+        self.colors.palette = t.colors.palette.current;
+        // Background/foreground can be unset initially which would
+        // depend on "default" background/foreground. The expected use
+        // case of Terminal is that the caller set their own configured
+        // defaults on load so this doesn't happen.
+        if let (Some(bg), Some(fg)) = (t.colors.background.get(), t.colors.foreground.get()) {
+            if t.modes.get(Mode::ReverseColors) {
+                self.colors.background = fg;
+                self.colors.foreground = bg;
+            } else {
+                self.colors.background = bg;
+                self.colors.foreground = fg;
+            }
+        }
+
+        // Ensure our row length is exactly our height, freeing or allocating
+        // data as necessary. In most cases we'll have a perfectly matching
+        // size.
+        let nrows = usize::from(self.rows);
+        if self.row_data.len() != nrows {
+            if self.row_data.len() < nrows {
+                let filler = viewport_pin;
+                self.row_data.resize_with(nrows, || Row {
+                    pin: filler,
+                    raw: page::Row::default(),
+                    cells: Cells::default(),
+                    dirty: true,
+                    selection: None,
+                    highlights: Vec::new(),
+                });
+            } else {
+                self.row_data.truncate(nrows);
+            }
+        }
+
+        // Go through and set up our row pins and find the cursor. We do the
+        // cursor even if the row is not dirty because the cursor is unrelated.
+        // We have to store pins even if we're not dirty because dirty is
+        // only a renderer optimization. It doesn't apply to memory movement.
+        // This will let us remap any cell pins back to an exact entry in our
+        // RenderState.
+        let cursor_pin = s.cursor_pin();
+        let mut y: usize = 0;
+        for row_pin in s.pages.row_iterator(
+            Direction::RightDown,
+            Point::Viewport(Coordinate::default()),
+            None,
+        ) {
+            if y >= nrows {
+                break;
+            }
+            if self.cursor.viewport.is_none()
+                && row_pin.node == cursor_pin.node
+                && row_pin.y == cursor_pin.y
+            {
+                self.cursor.viewport = Some(CursorViewport {
+                    y: y as size::CellCountInt,
+                    x: s.cursor.x,
+
+                    // Future: we should use our own state here to look this
+                    // up rather than calling this.
+                    wide_tail: if s.cursor.x > 0 {
+                        s.cursor_cell_left(1).wide() == Wide::Wide
+                    } else {
+                        false
+                    },
+                });
+            }
+            self.row_data[y].pin = row_pin;
+            y += 1;
+        }
+        assert_eq!(y, nrows);
+
+        // Track the last page that we know was dirty. This lets us
+        // more quickly do the full-page dirty check.
+        let mut last_dirty_page: Option<crate::page_list::NodeId> = None;
+        let mut any_dirty = false;
+        let cols = usize::from(self.cols);
+
+        for y in 0..nrows {
+            let row_pin = self.row_data[y].pin;
+            let node = s
+                .pages
+                .node_mut(row_pin.node)
+                .ok_or(Error::InvalidCoordinate)?;
+
+            let is_dirty = 'dirty: {
+                // If we're redrawing then we're definitely dirty.
+                if redraw {
+                    break 'dirty true;
+                }
+
+                // If our page is the same as last time then its dirty.
+                if last_dirty_page == Some(row_pin.node) {
+                    break 'dirty true;
+                }
+                if node.data.dirty {
+                    // If this page is dirty then clear the dirty flag
+                    // of the last page and then store this one. This benchmarks
+                    // faster than iterating pages again later.
+                    if let Some(last) = last_dirty_page
+                        && let Some(n) = s.pages.node_mut(last)
+                    {
+                        n.data.dirty = false;
+                    }
+                    last_dirty_page = Some(row_pin.node);
+                    break 'dirty true;
+                }
+
+                // If our row is dirty then we're dirty.
+                node.data
+                    .get_row(usize::from(row_pin.y))
+                    .is_some_and(|r| r.dirty())
+            };
+            if !is_dirty {
+                continue;
+            }
+
+            // Set that at least one row was dirty.
+            any_dirty = true;
+
+            // Clear our row dirty, we'll clear our page dirty later.
+            // We can't clear it now because we have more rows to go through.
+            let node = s
+                .pages
+                .node_mut(row_pin.node)
+                .ok_or(Error::InvalidCoordinate)?;
+            let raw_row = {
+                let r = node
+                    .data
+                    .get_row_mut(usize::from(row_pin.y))
+                    .ok_or(Error::InvalidCoordinate)?;
+                r.set_dirty(false);
+                *r
+            };
+            let p: &page::Page = &node.data;
+
+            let row = &mut self.row_data[y];
+
+            // Reset our cells if we're rebuilding this row.
+            if !row.cells.is_empty() {
+                row.cells.clear();
+                row.selection = None;
+                row.highlights.clear();
+            }
+            row.dirty = true;
+
+            // Get all our cells in the page.
+            let page_cells = p
+                .get_cells(usize::from(row_pin.y))
+                .ok_or(Error::InvalidCoordinate)?;
+            assert_eq!(page_cells.len(), cols);
+
+            // Copy our raw row data
+            row.raw = raw_row;
+
+            // We always copy our raw cell data. In the case we have no
+            // managed memory, we can skip setting any other fields.
+            //
+            // This is an important optimization. For plain-text screens
+            // this ends up being something around 300% faster based on
+            // the `screen-clone` benchmark.
+            row.cells.raw.extend_from_slice(page_cells);
+            if !raw_row.managed_memory() {
+                continue;
+            }
+
+            row.cells.grapheme.resize_with(cols, Vec::new);
+            row.cells.style.resize(cols, Style::default());
+            for (x, page_cell) in page_cells.iter().enumerate() {
+                // Append assuming its a single-codepoint, styled cell
+                // (most common by far).
+                if page_cell.style_id() > 0 {
+                    row.cells.style[x] = p.style(*page_cell);
+                }
+
+                // Switch on our content tag to handle less likely cases.
+                match page_cell.content_tag() {
+                    // Primary codepoint goes into `raw` field.
+                    ContentTag::Codepoint => {}
+
+                    // If we have a multi-codepoint grapheme, look it up and
+                    // set our content type.
+                    ContentTag::CodepointGrapheme => {
+                        if let Ok(idx) = p.cell_index(x, usize::from(row_pin.y))
+                            && let Some(g) = p.lookup_grapheme(idx)
+                        {
+                            row.cells.grapheme[x].extend_from_slice(g);
+                        }
+                    }
+
+                    ContentTag::BgColorRgb => {
+                        row.cells.style[x] = Style {
+                            bg_color: Color::Rgb(page_cell.color_rgb()),
+                            ..Style::default()
+                        };
+                    }
+
+                    ContentTag::BgColorPalette => {
+                        row.cells.style[x] = Style {
+                            bg_color: Color::Palette(page_cell.color_palette()),
+                            ..Style::default()
+                        };
+                    }
+                }
+            }
+        }
+
+        // If our screen has a selection, then mark the rows with the
+        // selection. We do this outside of the loop above because its unlikely
+        // a selection exists and because the way our selections are structured
+        // today is very inefficient.
+        //
+        // NOTE: To improve the performance of the block below, we'll need
+        // to rethink how we model selections in general.
+        //
+        // There are performance improvements that can be made here, though.
+        // For example, `contained_row` recalculates a bunch of information
+        // we can cache.
+        if let Some(sel) = s.selection {
+            'selection: {
+                // Populate our selection cache to avoid some expensive
+                // recalculation.
+                let cached = match self.selection_cache {
+                    // If we're redrawing, we recalculate the cache just to
+                    // be safe. If our selection isn't equal, we aren't cached!
+                    Some(c) if !redraw && c.selection.eql(&s.pages, &sel) => Some(c),
+                    _ => None,
+                };
+                let cache = if let Some(c) = cached {
+                    // If we have no dirty rows, we can not recalculate.
+                    if !any_dirty {
+                        break 'selection;
+                    }
+
+                    // We have dirty rows, we can utilize the cache.
+                    c
+                } else {
+                    // Create a new cache
+                    let tl_pin = sel.top_left(&s.pages);
+                    let br_pin = sel.bottom_right(&s.pages);
+                    let c = SelectionCache {
+                        selection: Selection::new(tl_pin, br_pin, sel.rectangle),
+                        tl_pin,
+                        br_pin,
+                    };
+                    self.selection_cache = Some(c);
+                    c
+                };
+
+                // Grab the inefficient data we need from the selection. At
+                // least we can cache it.
+                let tl = s
+                    .pages
+                    .point_from_pin(Tag::Screen, cache.tl_pin)
+                    .ok_or(Error::InvalidCoordinate)?
+                    .coord();
+                let br = s
+                    .pages
+                    .point_from_pin(Tag::Screen, cache.br_pin)
+                    .ok_or(Error::InvalidCoordinate)?
+                    .coord();
+
+                // We need to determine if our selection is within the viewport.
+                // The viewport is generally very small so the efficient way to
+                // do this is to traverse the viewport pages and check for the
+                // matching selection pages.
+                for row in &mut self.row_data {
+                    let pin = row.pin;
+                    let p = s
+                        .pages
+                        .point_from_pin(Tag::Screen, pin)
+                        .ok_or(Error::InvalidCoordinate)?
+                        .coord();
+                    let Some(row_sel) = sel.contained_row_cached(
+                        &s.pages,
+                        cache.tl_pin,
+                        cache.br_pin,
+                        pin,
+                        tl,
+                        br,
+                        p,
+                    ) else {
+                        continue;
+                    };
+                    let start = row_sel.start(&s.pages);
+                    let end = row_sel.end(&s.pages);
+                    assert_eq!(start.node, end.node);
+                    assert!(start.x <= end.x);
+                    assert_eq!(start.y, end.y);
+                    row.selection = Some([start.x, end.x]);
+                }
+            }
+        }
+
+        // Handle dirty state.
+        if redraw {
+            // Fully redraw resets some other state.
+            self.screen = active_key;
+            self.dirty = Dirty::Full;
+
+            // Note: we don't clear any row_data here because our rebuild
+            // above did this.
+        } else if any_dirty && self.dirty == Dirty::False {
+            self.dirty = Dirty::Partial;
+        }
+
+        // Finalize our final dirty page
+        if let Some(last) = last_dirty_page
+            && let Some(n) = s.pages.node_mut(last)
+        {
+            n.data.dirty = false;
+        }
+
+        // Clear our dirty flags
+        t.flags.dirty = TerminalDirty::default();
+        s.dirty = crate::screen::Dirty::default();
+        Ok(())
+    }
+
+    /// Update the highlights in the render state from the given flattened
+    /// highlights. Because this uses flattened highlights, it does not require
+    /// reading from the terminal state so it should be done outside of
+    /// any critical sections.
+    ///
+    /// This will not clear any previous highlights, so the caller must
+    /// manually clear them if desired.
+    pub fn update_highlights_flattened(&mut self, tag: u8, hls: &[Flattened]) {
+        // Fast path, we have no highlights!
+        if hls.is_empty() {
+            return;
+        }
+
+        // This is, admittedly, horrendous. This is some low hanging fruit
+        // to optimize. In my defense, screens are usually small, the number
+        // of highlights is usually small, and this only happens on the
+        // viewport outside of a locked area. Still, I'd love to see this
+        // improved someday.
+
+        // We need to track whether any row had a match so we can mark
+        // the dirty state.
+        let mut any_dirty = false;
+        let cols = self.cols;
+
+        for row in &mut self.row_data {
+            let row_pin = row.pin;
+            for hl in hls {
+                let n = hl.chunks.len();
+                for (i, chunk) in hl.chunks.iter().enumerate() {
+                    // If this node doesn't match or we're not within
+                    // the row range, skip it.
+                    if chunk.node != row_pin.node
+                        || row_pin.y < chunk.start
+                        || row_pin.y >= chunk.end
+                    {
+                        continue;
+                    }
+
+                    // We're a match!
+                    row.highlights.push(Highlight {
+                        tag,
+                        range: [
+                            if i == 0 && row_pin.y == hl.chunks[0].start {
+                                hl.top_x
+                            } else {
+                                0
+                            },
+                            if i == n - 1 && row_pin.y == hl.chunks[n - 1].end - 1 {
+                                hl.bot_x
+                            } else {
+                                cols - 1
+                            },
+                        ],
+                    });
+
+                    row.dirty = true;
+                    any_dirty = true;
+                }
+            }
+        }
+
+        // Mark our dirty state.
+        if any_dirty && self.dirty == Dirty::False {
+            self.dirty = Dirty::Partial;
+        }
+    }
+
+    /// Convert the current render state contents to a UTF-8 encoded
+    /// string written to the given string. This will unwrap all the wrapped
+    /// rows. This is useful for a minimal viewport search.
+    ///
+    /// This currently writes empty cell contents as \x00 and writes all
+    /// blank lines. This is fine for our current usage (link search) but
+    /// we can adjust this later.
+    ///
+    /// If `map` is given, every byte written gets the coordinate of the cell
+    /// it came from appended (a newline maps to `x = cols`).
+    ///
+    /// NOTE: There is a limitation in that wrapped lines before/after
+    /// the the top/bottom line of the viewport are not included, since
+    /// the render state cuts them off.
+    ///
+    /// Returns `Err` if a cell holds an invalid Unicode scalar value.
+    pub fn string(
+        &self,
+        out: &mut String,
+        mut map: Option<&mut Vec<Coordinate>>,
+    ) -> Result<(), std::fmt::Error> {
+        for (y, row) in self.row_data.iter().enumerate() {
+            for (x, cell) in row.cells.raw.iter().enumerate() {
+                let coord = Coordinate {
+                    x: x as u16,
+                    y: y as u32,
+                };
+                let c = char::from_u32(cell.codepoint()).ok_or(std::fmt::Error)?;
+                let mut len = c.len_utf8();
+                out.push(c);
+                if cell.has_grapheme() {
+                    for &cp in row.cells.grapheme(x) {
+                        let c = char::from_u32(cp).ok_or(std::fmt::Error)?;
+                        len += c.len_utf8();
+                        out.push(c);
+                    }
+                }
+
+                if let Some(m) = map.as_deref_mut() {
+                    m.extend(std::iter::repeat_n(coord, len));
+                }
+            }
+
+            if !row.raw.wrap() {
+                out.push('\n');
+                if let Some(m) = map.as_deref_mut() {
+                    m.push(Coordinate {
+                        x: row.cells.len() as u16,
+                        y: y as u32,
+                    });
+                }
+            }
+        }
+        Ok(())
+    }
+
+    /// Returns a set of the cells that match to an OSC8 hyperlink over the
+    /// given point in the render state.
+    ///
+    /// IMPORTANT: The terminal must not have updated since the last call to
+    /// `update`. If there is any chance the terminal has updated, the caller
+    /// must first call `update` again to refresh the render state.
+    ///
+    /// For example, you may want to hold a lock for the duration of the
+    /// update and hyperlink lookup to ensure no updates happen in between.
+    ///
+    /// Unlike Zig (where pins hold page pointers) the page list the pins
+    /// belong to must be passed (`&terminal.screen().pages`).
+    pub fn link_cells(&self, pages: &PageList, viewport_point: Coordinate) -> HashSet<Coordinate> {
+        let mut result = HashSet::new();
+
+        // Our viewport point is sent in by the caller and can't be trusted.
+        // If it is outside the valid area then just return empty because
+        // we can't possibly have a link there.
+        if viewport_point.x >= self.cols || viewport_point.y as usize >= self.row_data.len() {
+            return result;
+        }
+
+        // Grab our link ID
+        let link_pin = self.row_data[viewport_point.y as usize].pin;
+        let Some(link_node) = pages.node(link_pin.node) else {
+            return result;
+        };
+        let link_page = &link_node.data;
+        let Some(link) = ({
+            let x = usize::from(viewport_point.x);
+            let y = usize::from(link_pin.y);
+            let Some((_, cell)) = link_page.get_row_and_cell(x, y) else {
+                return result;
+            };
+
+            // The likely scenario is that our mouse isn't even over a link.
+            if !cell.hyperlink() {
+                return result;
+            }
+
+            let Ok(idx) = link_page.cell_index(x, y) else {
+                return result;
+            };
+            let Some(link_id) = link_page.lookup_hyperlink(idx) else {
+                return result;
+            };
+            link_page.hyperlink_set.get(link_id)
+        }) else {
+            return result;
+        };
+
+        for (y, row) in self.row_data.iter().enumerate() {
+            let pin = row.pin;
+            let Some(other_node) = pages.node(pin.node) else {
+                continue;
+            };
+            let other_page = &other_node.data;
+            for (x, cell) in row.cells.raw.iter().enumerate() {
+                if !cell.hyperlink() {
+                    continue;
+                }
+
+                let Ok(idx) = other_page.cell_index(x, usize::from(pin.y)) else {
+                    continue;
+                };
+                let Some(link_id) = other_page.lookup_hyperlink(idx) else {
+                    continue;
+                };
+                let Some(other) = other_page.hyperlink_set.get(link_id) else {
+                    continue;
+                };
+
+                if link.eql(other) {
+                    result.insert(Coordinate {
+                        y: y as u32,
+                        x: x as u16,
+                    });
+                }
+            }
+        }
+
+        result
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use crate::terminal::Options;
+
+    fn term(cols: u16, rows: u16) -> Terminal {
+        Terminal::new(Options::new(cols, rows)).unwrap()
+    }
+
+    fn feed(t: &mut Terminal, bytes: &[u8]) {
+        let mut s = t.vt_stream();
+        s.next_slice(bytes).unwrap();
+    }
+
+    fn clear_dirty(state: &mut RenderState) {
+        state.dirty = Dirty::False;
+        for r in &mut state.row_data {
+            r.dirty = false;
+        }
+    }
+
+    #[test]
+    fn styled() {
+        let mut t = term(80, 24);
+
+        // This fills the screen up
+        t.decaln().unwrap();
+
+        let mut state = RenderState::new();
+        state.update(&mut t).unwrap();
+    }
+
+    #[test]
+    fn basic_text() {
+        let mut t = term(10, 3);
+        feed(&mut t, b"ABCD");
+
+        let mut state = RenderState::new();
+        state.update(&mut t).unwrap();
+
+        // Verify we have the right number of rows
+        assert_eq!(state.row_data.len(), 3);
+
+        // All rows should have cols cells
+        for r in &state.row_data {
+            assert_eq!(r.cells.len(), 10);
+        }
+
+        // Row zero should contain our text
+        let cells = &state.row_data[0].cells;
+        assert_eq!(cells.get(0).raw.codepoint(), 'A' as u32);
+        assert_eq!(cells.get(1).raw.codepoint(), 'B' as u32);
+        assert_eq!(cells.get(2).raw.codepoint(), 'C' as u32);
+        assert_eq!(cells.get(3).raw.codepoint(), 'D' as u32);
+        assert_eq!(cells.get(4).raw.codepoint(), 0);
+    }
+
+    #[test]
+    fn styled_text() {
+        let mut t = term(10, 3);
+        feed(&mut t, b"\x1b[1mA"); // Bold
+        feed(&mut t, b"\x1b[0;3mB"); // Italic
+        feed(&mut t, b"\x1b[0;4mC"); // Underline
+
+        let mut state = RenderState::new();
+        state.update(&mut t).unwrap();
+
+        assert_eq!(state.row_data.len(), 3);
+        for r in &state.row_data {
+            assert_eq!(r.cells.len(), 10);
+        }
+
+        let cells = &state.row_data[0].cells;
+        {
+            let cell = cells.get(0);
+            assert_eq!(cell.raw.codepoint(), 'A' as u32);
+            assert!(cell.style.flags.bold);
+        }
+        {
+            let cell = cells.get(1);
+            assert_eq!(cell.raw.codepoint(), 'B' as u32);
+            assert!(!cell.style.flags.bold);
+            assert!(cell.style.flags.italic);
+        }
+        assert_eq!(cells.get(2).raw.codepoint(), 'C' as u32);
+        assert_eq!(cells.get(3).raw.codepoint(), 0);
+    }
+
+    #[test]
+    fn grapheme() {
+        let mut t = term(10, 3);
+        feed(&mut t, b"A");
+        feed(&mut t, "\u{1F468}\u{200D}".as_bytes()); // this has a ZWJ
+
+        let mut state = RenderState::new();
+        state.update(&mut t).unwrap();
+
+        assert_eq!(state.row_data.len(), 3);
+        for r in &state.row_data {
+            assert_eq!(r.cells.len(), 10);
+        }
+
+        let cells = &state.row_data[0].cells;
+        assert_eq!(cells.get(0).raw.codepoint(), 'A' as u32);
+        {
+            let cell = cells.get(1);
+            assert_eq!(cell.raw.codepoint(), 0x1F468);
+            assert_eq!(cell.raw.wide(), Wide::Wide);
+            assert_eq!(cell.grapheme, &[0x200D]);
+        }
+        {
+            let cell = cells.get(2);
+            assert_eq!(cell.raw.codepoint(), 0);
+            assert_eq!(cell.raw.wide(), Wide::SpacerTail);
+        }
+    }
+
+    #[test]
+    fn cursor_state_in_viewport() {
+        let mut t = term(10, 5);
+        feed(&mut t, b"A\x1b[H");
+
+        let mut state = RenderState::new();
+
+        // Initial update
+        state.update(&mut t).unwrap();
+        assert_eq!(state.cursor.active.x, 0);
+        assert_eq!(state.cursor.active.y, 0);
+        assert_eq!(state.cursor.viewport.unwrap().x, 0);
+        assert_eq!(state.cursor.viewport.unwrap().y, 0);
+        assert_eq!(state.cursor.cell.codepoint(), 'A' as u32);
+        assert!(state.cursor.style.is_default());
+
+        // Set a style on the cursor
+        feed(&mut t, b"\x1b[1m"); // Bold
+        state.update(&mut t).unwrap();
+        assert!(!state.cursor.style.is_default());
+        assert!(state.cursor.style.flags.bold);
+        feed(&mut t, b"\x1b[0m"); // Reset style
+
+        // Move cursor to 2,1
+        feed(&mut t, b"\x1b[2;3H");
+        state.update(&mut t).unwrap();
+        assert_eq!(state.cursor.active.x, 2);
+        assert_eq!(state.cursor.active.y, 1);
+        assert_eq!(state.cursor.viewport.unwrap().x, 2);
+        assert_eq!(state.cursor.viewport.unwrap().y, 1);
+    }
+
+    #[test]
+    fn cursor_state_out_of_viewport() {
+        let mut t = term(10, 2);
+        feed(&mut t, b"A\r\nB\r\nC\r\nD\r\n");
+
+        let mut state = RenderState::new();
+
+        // Initial update
+        state.update(&mut t).unwrap();
+        assert_eq!(state.cursor.active.x, 0);
+        assert_eq!(state.cursor.active.y, 1);
+        assert_eq!(state.cursor.viewport.unwrap().x, 0);
+        assert_eq!(state.cursor.viewport.unwrap().y, 1);
+
+        // Scroll the viewport
+        t.scroll_viewport(crate::terminal::ScrollViewport::Top);
+        state.update(&mut t).unwrap();
+
+        // Set a style on the cursor
+        assert_eq!(state.cursor.active.x, 0);
+        assert_eq!(state.cursor.active.y, 1);
+        assert!(state.cursor.viewport.is_none());
+    }
+
+    #[test]
+    fn dirty_state() {
+        let mut t = term(10, 5);
+
+        let mut state = RenderState::new();
+
+        // First update should trigger redraw due to resize
+        state.update(&mut t).unwrap();
+        assert_eq!(state.dirty, Dirty::Full);
+
+        // Reset dirty flag and dirty rows
+        clear_dirty(&mut state);
+
+        // Second update with no changes - no dirty rows
+        state.update(&mut t).unwrap();
+        assert_eq!(state.dirty, Dirty::False);
+        for r in &state.row_data {
+            assert!(!r.dirty);
+        }
+
+        // Write to first line
+        feed(&mut t, b"A");
+        state.update(&mut t).unwrap();
+        assert_eq!(state.dirty, Dirty::Partial);
+        assert!(state.row_data[0].dirty); // First row dirty
+        assert!(!state.row_data[1].dirty); // Second row clean
+    }
+
+    #[test]
+    fn colors() {
+        let mut t = term(10, 5);
+
+        let mut state = RenderState::new();
+
+        // Default colors
+        state.update(&mut t).unwrap();
+
+        // Change cursor color
+        feed(&mut t, b"\x1b]12;#FF0000\x07");
+        state.update(&mut t).unwrap();
+
+        let c = state.colors.cursor.unwrap();
+        assert_eq!(c.r, 0xFF);
+        assert_eq!(c.g, 0);
+        assert_eq!(c.b, 0);
+
+        // Change palette color 0 to White
+        feed(&mut t, b"\x1b]4;0;#FFFFFF\x07");
+        state.update(&mut t).unwrap();
+        let p0 = state.colors.palette[0];
+        assert_eq!(p0.r, 0xFF);
+        assert_eq!(p0.g, 0xFF);
+        assert_eq!(p0.b, 0xFF);
+    }
+
+    fn pin_active(t: &Terminal, x: u16, y: u32) -> Pin {
+        t.screen()
+            .pages
+            .pin(Point::Active(Coordinate { x, y }))
+            .unwrap()
+    }
+
+    #[test]
+    fn selection_single_line() {
+        let mut t = term(10, 3);
+
+        let (a, b) = (pin_active(&t, 0, 1), pin_active(&t, 2, 1));
+        t.screen_mut()
+            .select(Some(Selection::new(a, b, false)))
+            .unwrap();
+
+        let mut state = RenderState::new();
+        state.update(&mut t).unwrap();
+
+        assert_eq!(state.row_data[0].selection, None);
+        assert_eq!(state.row_data[1].selection, Some([0, 2]));
+        assert_eq!(state.row_data[2].selection, None);
+
+        // Clear the selection
+        t.screen_mut().select(None).unwrap();
+        state.update(&mut t).unwrap();
+        assert_eq!(state.row_data[0].selection, None);
+        assert_eq!(state.row_data[1].selection, None);
+        assert_eq!(state.row_data[2].selection, None);
+    }
+
+    #[test]
+    fn selection_multiple_lines() {
+        let mut t = term(10, 3);
+
+        let (a, b) = (pin_active(&t, 0, 1), pin_active(&t, 2, 2));
+        t.screen_mut()
+            .select(Some(Selection::new(a, b, false)))
+            .unwrap();
+
+        let mut state = RenderState::new();
+        state.update(&mut t).unwrap();
+
+        assert_eq!(state.row_data[0].selection, None);
+        assert_eq!(
+            state.row_data[1].selection,
+            Some([0, t.screen().pages.cols - 1])
+        );
+        assert_eq!(state.row_data[2].selection, Some([0, 2]));
+    }
+
+    #[test]
+    fn link_cells() {
+        let mut t = term(10, 5);
+
+        let mut state = RenderState::new();
+
+        // Create a hyperlink
+        feed(
+            &mut t,
+            b"\x1b]8;;http://example.com\x1b\\LINK\x1b]8;;\x1b\\",
+        );
+        state.update(&mut t).unwrap();
+
+        // Query link at 0,0
+        let cells = state.link_cells(&t.screen().pages, Coordinate { x: 0, y: 0 });
+        assert_eq!(cells.len(), 4);
+        assert!(cells.contains(&Coordinate { x: 0, y: 0 }));
+        assert!(cells.contains(&Coordinate { x: 1, y: 0 }));
+        assert!(cells.contains(&Coordinate { x: 2, y: 0 }));
+        assert!(cells.contains(&Coordinate { x: 3, y: 0 }));
+
+        // Query no link
+        let cells2 = state.link_cells(&t.screen().pages, Coordinate { x: 4, y: 0 });
+        assert_eq!(cells2.len(), 0);
+    }
+
+    #[test]
+    fn string() {
+        let mut t = term(5, 2);
+        feed(&mut t, b"AB");
+
+        let mut state = RenderState::new();
+        state.update(&mut t).unwrap();
+
+        let mut result = String::new();
+        state.string(&mut result, None).unwrap();
+
+        let expected = "AB\x00\x00\x00\n\x00\x00\x00\x00\x00\n";
+        assert_eq!(result, expected);
+
+        // With a map, every byte maps to its cell; newline maps to x = cols.
+        let mut result = String::new();
+        let mut map = Vec::new();
+        state.string(&mut result, Some(&mut map)).unwrap();
+        assert_eq!(map.len(), result.len());
+        assert_eq!(map[0], Coordinate { x: 0, y: 0 });
+        assert_eq!(map[5], Coordinate { x: 5, y: 0 });
+        assert_eq!(map[6], Coordinate { x: 0, y: 1 });
+    }
+
+    #[test]
+    fn link_cells_with_scrollback_spanning_pages() {
+        let viewport_rows: u16 = 10;
+        let tail_rows: u16 = 5;
+
+        let mut t = Terminal::new(Options {
+            max_scrollback: 10_000,
+            ..Options::new(page::STD_CAPACITY.cols, viewport_rows)
+        })
+        .unwrap();
+
+        let first_page_cap = {
+            let pages = &t.screen().pages;
+            pages.node(pages.first.unwrap()).unwrap().data.capacity.rows
+        };
+
+        // Fill first page
+        for _ in 0..first_page_cap - 1 {
+            feed(&mut t, b"\r\n");
+        }
+
+        // Create second page with hyperlink
+        feed(&mut t, b"\r\n");
+        feed(
+            &mut t,
+            b"\x1b]8;;http://example.com\x1b\\LINK\x1b]8;;\x1b\\",
+        );
+        for _ in 0..tail_rows - 1 {
+            feed(&mut t, b"\r\n");
+        }
+
+        let mut state = RenderState::new();
+        state.update(&mut t).unwrap();
+
+        let expected_viewport_y = u32::from(viewport_rows - tail_rows);
+        let cells = state.link_cells(
+            &t.screen().pages,
+            Coordinate {
+                x: 0,
+                y: expected_viewport_y,
+            },
+        );
+        assert_eq!(cells.len(), 4);
+    }
+
+    #[test]
+    fn link_cells_with_invalid_viewport_point() {
+        let mut t = term(10, 5);
+
+        let mut state = RenderState::new();
+        state.update(&mut t).unwrap();
+
+        // Row out of bound
+        let cells = state.link_cells(
+            &t.screen().pages,
+            Coordinate {
+                x: 0,
+                y: u32::from(t.rows) + 10,
+            },
+        );
+        assert_eq!(cells.len(), 0);
+
+        // Col out of bound
+        let cells = state.link_cells(
+            &t.screen().pages,
+            Coordinate {
+                x: t.cols + 10,
+                y: 0,
+            },
+        );
+        assert_eq!(cells.len(), 0);
+    }
+
+    #[test]
+    fn dirty_row_resets_highlights() {
+        let mut t = term(10, 3);
+        feed(&mut t, b"ABC");
+
+        let mut state = RenderState::new();
+        state.update(&mut t).unwrap();
+
+        // Reset dirty state
+        clear_dirty(&mut state);
+
+        // Manually add a highlight to row 0
+        state.row_data[0].highlights.push(Highlight {
+            tag: 1,
+            range: [0, 2],
+        });
+        assert_eq!(state.row_data[0].highlights.len(), 1);
+
+        // Write to row 0 to make it dirty
+        feed(&mut t, b"\x1b[H"); // Move to home
+        feed(&mut t, b"X");
+        state.update(&mut t).unwrap();
+
+        // Verify the highlight was reset on the dirty row
+        assert_eq!(state.row_data[0].highlights.len(), 0);
+    }
+
+    // Additional tests (not in Zig).
+
+    #[test]
+    fn bg_color_cell_style() {
+        let mut t = term(10, 3);
+        // The row must have managed memory (a styled cell) for the style of
+        // bg-color-only cells to be populated (same as Zig).
+        feed(&mut t, b"\x1b[48;2;1;2;3mA\x1b[K");
+        let mut state = RenderState::new();
+        state.update(&mut t).unwrap();
+        let cell = state.row_data[0].cells.get(5);
+        assert_eq!(cell.raw.content_tag(), ContentTag::BgColorRgb);
+        assert_eq!(cell.style.bg_color, Color::Rgb(Rgb { r: 1, g: 2, b: 3 }));
+    }
+
+    #[test]
+    fn update_highlights_flattened() {
+        let mut t = term(10, 3);
+        feed(&mut t, b"ABC");
+        let mut state = RenderState::new();
+        state.update(&mut t).unwrap();
+        clear_dirty(&mut state);
+
+        let pages = &t.screen().pages;
+        let start = pages
+            .pin(Point::Viewport(Coordinate { x: 1, y: 0 }))
+            .unwrap();
+        let end = pages
+            .pin(Point::Viewport(Coordinate { x: 4, y: 1 }))
+            .unwrap();
+        let hl = Flattened::init(pages, start, end).unwrap();
+        state.update_highlights_flattened(7, &[hl]);
+        assert_eq!(state.dirty, Dirty::Partial);
+        assert_eq!(
+            state.row_data[0].highlights,
+            vec![Highlight {
+                tag: 7,
+                range: [1, 9]
+            }]
+        );
+        assert_eq!(
+            state.row_data[1].highlights,
+            vec![Highlight {
+                tag: 7,
+                range: [0, 4]
+            }]
+        );
+        assert_eq!(state.row_data[2].highlights, vec![]);
+        assert!(state.row_data[0].dirty && state.row_data[1].dirty);
+        assert!(!state.row_data[2].dirty);
+    }
+}

crates/ghostty-terminal/src/screen.rs

@@ -20,6 +20,7 @@
 )]
 use crate::{
     cursor::Style as CursorStyle,
+    formatter::{Content as FormatContent, Options as FormatOptions, ScreenFormatter},
     hyperlink::{self, Hyperlink, HyperlinkId},
     page::{Cell, ContentTag, Page, Row, SemanticContent, SemanticPrompt as RowPrompt, Wide},
     page_list::{
@@ -2617,19 +2618,23 @@ impl Screen {
         opts: SelectionString,
         pin_map: Option<&mut Vec<Pin>>,
     ) -> String {
-        // TODO(integration): delegate to formatter::ScreenFormatter (plain,
-        // unwrap = true, trim = opts.trim, content = selection).
-        let tl = opts.sel.top_left(&self.pages);
-        let br = opts.sel.bottom_right(&self.pages);
-        plain_format(
-            &self.pages,
-            tl,
-            br,
-            opts.sel.rectangle,
-            true,
-            opts.trim,
-            pin_map,
-        )
+        // Create a formatter and use that to emit our text.
+        let mut formatter = ScreenFormatter::new(
+            self,
+            FormatOptions {
+                unwrap: true,
+                trim: opts.trim,
+                ..FormatOptions::plain()
+            },
+        );
+        formatter.content = FormatContent::Selection(Some(opts.sel));
+
+        // If we have a string map, we need to set that up.
+        formatter.pin_map = pin_map;
+
+        formatter
+            .format_string()
+            .expect("formatting to memory cannot fail")
     }
 
     /// Select the line under the given point. This will select across soft-wrapped
@@ -3224,23 +3229,31 @@ impl Screen {
 
     /// Dump the screen to a string.
     pub fn dump_string(&self, out: &mut String, opts: DumpString) {
-        // TODO(integration): delegate to formatter::ScreenFormatter (plain,
-        // unwrap = opts.unwrap, trim = false, content = selection(tl, br)).
+        // Create a formatter and use that to emit our text.
+        let mut formatter = ScreenFormatter::new(
+            self,
+            FormatOptions {
+                unwrap: opts.unwrap,
+                trim: false,
+                ..FormatOptions::plain()
+            },
+        );
+
+        // Set up the selection based on the pins
+        let tl = opts.tl;
         let br = opts
             .br
             .unwrap_or_else(|| self.pages.get_bottom_right(Tag::Screen).expect("screen"));
-        let sel = Selection::new(opts.tl, br, false);
-        let tl = sel.top_left(&self.pages);
-        let br = sel.bottom_right(&self.pages);
-        out.push_str(&plain_format(
-            &self.pages,
-            tl,
-            br,
-            false,
-            opts.unwrap,
-            false,
-            None,
-        ));
+        formatter.content = FormatContent::Selection(Some(Selection::new(
+            tl, br, false, // not rectangle
+        )));
+
+        // Emit
+        out.push_str(
+            &formatter
+                .format_string()
+                .expect("formatting to memory cannot fail"),
+        );
     }
 
     /// You should use dump_string, this is a restricted version mostly for
@@ -3471,334 +3484,5 @@ impl Iterator for LineIterator<'_> {
     }
 }
 
-// ---------------------------------------------------------------------------
-// Minimal plain-text formatter.
-//
-// TODO(integration): this is a minimal port of the `emit = .plain` paths of
-// formatter.zig's PageListFormatter/PageFormatter (unwrapping soft-wrapped
-// lines, trimming trailing whitespace, trailing blank lines are dropped).
-// Replace with the real formatter once ported.
-// ---------------------------------------------------------------------------
-
-/// Trailing state carried between pages (formatter.zig `TrailingState`).
-#[derive(Clone, Copy, Default)]
-struct TrailingState {
-    rows: usize,
-    cells: usize,
-}
-
-fn write_codepoint(
-    out: &mut String,
-    cp: u32,
-    map: &mut Option<&mut Vec<(u16, u16)>>,
-    x: u16,
-    y: u16,
-) {
-    let ch = char::from_u32(cp).unwrap_or(char::REPLACEMENT_CHARACTER);
-    let before = out.len();
-    out.push(ch);
-    if let Some(map) = map {
-        for _ in before..out.len() {
-            map.push((x, y));
-        }
-    }
-}
-
-#[allow(clippy::too_many_arguments)]
-fn plain_format_page(
-    page: &Page,
-    out: &mut String,
-    start_x: u16,
-    start_y: u16,
-    end_x: Option<u16>,
-    end_y: Option<u16>,
-    rectangle: bool,
-    unwrap: bool,
-    trim: bool,
-    trailing_state: Option<TrailingState>,
-    mut point_map: Option<&mut Vec<(u16, u16)>>,
-) -> TrailingState {
-    let mut blank_rows: usize = 0;
-    let mut blank_cells: usize = 0;
-
-    // Continue our prior trailing state if we have it, but only if we're
-    // starting from the beginning (start_y and start_x are both 0).
-    // If a non-zero start position is specified, ignore trailing state.
-    if let Some(state) = trailing_state
-        && start_y == 0
-        && start_x == 0
-    {
-        blank_rows = state.rows;
-        blank_cells = state.cells;
-    }
-    let ret = |blank_rows, blank_cells| TrailingState {
-        rows: blank_rows,
-        cells: blank_cells,
-    };
-
-    // Setup our starting column and perform some validation for overflows.
-    if start_x >= page.size.cols {
-        return ret(blank_rows, blank_cells);
-    }
-    let end_x_unclamped = end_x.unwrap_or(page.size.cols - 1);
-    let mut end_x = end_x_unclamped.min(page.size.cols - 1);
-
-    // Setup our starting row and perform some validation for overflows.
-    if start_y >= page.size.rows {
-        return ret(blank_rows, blank_cells);
-    }
-    let end_y_unclamped = end_y.unwrap_or(page.size.rows - 1);
-    if start_y > end_y_unclamped {
-        return ret(blank_rows, blank_cells);
-    }
-    let mut end_y = end_y_unclamped.min(page.size.rows - 1);
-
-    // Edge case: if our end x/y falls on a spacer head AND we're unwrapping,
-    // then we move the x/y to the start of the next row (if available).
-    if unwrap && !rectangle {
-        let cells = page.get_cells(usize::from(end_y)).expect("row");
-        if cells[usize::from(end_x)].wide() == Wide::SpacerHead && end_y < page.size.rows - 1 {
-            end_y += 1;
-            end_x = 0;
-        }
-    }
-
-    // If we only have a single row, validate that start_x <= end_x
-    if start_y == end_y && start_x > end_x {
-        return ret(blank_rows, blank_cells);
-    }
-
-    for y in start_y..=end_y {
-        let row = *page.get_row(usize::from(y)).expect("row");
-        let cells = page.get_cells(usize::from(y)).expect("row cells");
-        let base = row.cells();
-
-        // Determine the x range for this row
-        // - First row: start_x to end of row (or end_x if single row)
-        // - Last row: start of row to end_x
-        // - Middle rows: full width
-        let row_end_x: u16 = if rectangle || y == end_y {
-            end_x + 1
-        } else {
-            page.size.cols
-        };
-
-        // The first we have to check if our start X falls on the
-        // tail of a wide character.
-        let row_start_x: u16 = if start_x > 0 && (rectangle || y == start_y) {
-            match cells[usize::from(start_x)].wide() {
-                // Include the prior cell to get the full wide char
-                Wide::SpacerTail => start_x - 1,
-
-                // If we're a spacer head on our first row then we
-                // skip this whole row.
-                Wide::SpacerHead => continue,
-
-                Wide::Narrow | Wide::Wide => start_x,
-            }
-        } else {
-            0
-        };
-
-        let subset = &cells[usize::from(row_start_x)..usize::from(row_end_x)];
-
-        // If this row is blank, accumulate to avoid a bunch of extra
-        // work later. If it isn't blank, make sure we dump all our
-        // blanks.
-        if !Cell::has_text_any(subset) {
-            blank_rows += 1;
-            continue;
-        }
-
-        if blank_rows > 0 {
-            for _ in 0..blank_rows {
-                out.push('\n');
-            }
-
-            // \r and \n map to the row that ends with this newline.
-            // If we're continuing (trailing state) then this will be
-            // in a prior page, so we just map to the first row of this
-            // page.
-            if let Some(map) = point_map.as_deref_mut() {
-                let start = map.last().copied().unwrap_or((0, 0));
-
-                // The first one inherits the x value.
-                map.push(start);
-
-                // All others have x = 0 since they reference their prior
-                // blank line.
-                for y_offset in 1..blank_rows {
-                    map.push((0, start.1 + y_offset as u16));
-                }
-            }
-
-            blank_rows = 0;
-        }
-
-        // If we're not wrapped, we always add a newline so after
-        // the row is printed we can add a newline.
-        if !row.wrap() || !unwrap {
-            blank_rows += 1;
-        }
-
-        // If the row doesn't continue a wrap then we need to reset
-        // our blank cell count.
-        if !row.wrap_continuation() || !unwrap {
-            blank_cells = 0;
-        }
-
-        // Go through each cell and print it
-        for (offset, cell) in subset.iter().enumerate() {
-            let x = row_start_x + offset as u16;
-
-            // Skip spacers. These happen naturally when wide characters
-            // are printed again on the screen (for well-behaved terminals!)
-            match cell.wide() {
-                Wide::Narrow | Wide::Wide => {}
-                Wide::SpacerHead | Wide::SpacerTail => continue,
-            }
-
-            // If we have a zero value, then we accumulate a counter. We
-            // only want to turn zero values into spaces if we have a non-zero
-            // char sometime later.
-            // Cells with no text are blank
-            if !cell.has_text() {
-                blank_cells += 1;
-                continue;
-            }
-
-            // Trailing spaces are blank. We know it is trailing
-            // because if we get a non-empty cell later we'll
-            // fill the blanks.
-            if cell.codepoint() == u32::from(' ') && trim {
-                blank_cells += 1;
-                continue;
-            }
-
-            // This cell is not blank. If we have accumulated blank cells
-            // then we want to emit them now.
-            if blank_cells > 0 {
-                for _ in 0..blank_cells {
-                    out.push(' ');
-                }
-
-                if let Some(map) = point_map.as_deref_mut() {
-                    // Map each blank cell to its coordinate. Blank cells can span
-                    // multiple rows if they carry over from wrap continuation.
-                    let mut remaining_blanks = blank_cells;
-                    let mut blank_x = x;
-                    let mut blank_y = y;
-                    while remaining_blanks > 0 {
-                        if blank_x > 0 {
-                            // We have space in this row
-                            blank_x -= 1;
-                        } else if blank_y > 0 {
-                            // Wrap to previous row
-                            blank_y -= 1;
-                            blank_x = page.size.cols - 1;
-                        } else {
-                            // Can't go back further, just use (0, 0)
-                            blank_x = 0;
-                            blank_y = 0;
-                        }
-
-                        map.push((blank_x, blank_y));
-                        remaining_blanks -= 1;
-                    }
-                }
-
-                blank_cells = 0;
-            }
-
-            write_codepoint(out, cell.codepoint(), &mut point_map, x, y);
-            if cell.content_tag() == ContentTag::CodepointGrapheme
-                && let Some(extra) = page.lookup_grapheme(base + usize::from(x))
-            {
-                for &cp in extra {
-                    write_codepoint(out, cp, &mut point_map, x, y);
-                }
-            }
-        }
-    }
-
-    ret(blank_rows, blank_cells)
-}
-
-/// Plain-text format of the pages between `tl` and `br` (both inclusive,
-/// properly ordered).
-fn plain_format(
-    list: &PageList,
-    tl: Pin,
-    br: Pin,
-    rectangle: bool,
-    unwrap: bool,
-    trim: bool,
-    mut pin_map: Option<&mut Vec<Pin>>,
-) -> String {
-    let mut out = String::new();
-    let mut page_state: Option<TrailingState> = None;
-    let mut point_map: Vec<(u16, u16)> = Vec::new();
-
-    let mut node = Some(tl.node);
-    while let Some(id) = node {
-        let n = list.node(id).expect("live node");
-        let chunk_start = if id == tl.node { tl.y } else { 0 };
-        let chunk_end = if id == br.node {
-            br.y + 1
-        } else {
-            n.data.size.rows
-        };
-        debug_assert!(chunk_start < chunk_end);
-
-        let (start_x, end_x) = if rectangle {
-            // For rectangle selection, apply start_x and end_x to all chunks
-            (tl.x, Some(br.x))
-        } else {
-            // Otherwise only on the first/last, respectively.
-            (
-                if id == tl.node { tl.x } else { 0 },
-                if id == br.node { Some(br.x) } else { None },
-            )
-        };
-
-        point_map.clear();
-        page_state = Some(plain_format_page(
-            &n.data,
-            &mut out,
-            start_x,
-            chunk_start,
-            end_x,
-            Some(chunk_end - 1),
-            rectangle,
-            unwrap,
-            trim,
-            page_state,
-            if pin_map.is_some() {
-                Some(&mut point_map)
-            } else {
-                None
-            },
-        ));
-
-        if let Some(m) = pin_map.as_deref_mut() {
-            for &(x, y) in &point_map {
-                m.push(Pin {
-                    node: id,
-                    x,
-                    y,
-                    garbage: false,
-                });
-            }
-        }
-
-        if id == br.node {
-            break;
-        }
-        node = n.next;
-    }
-
-    out
-}
-
 #[cfg(test)]
 mod tests;