use std::{
    env,
    fs,
    path::{Path, PathBuf},
};

use build_support::catalog_gate::{
    CatalogBuildMode,
    CatalogGateInput,
    select_catalog_build_mode,
    validate_production_catalog,
};

mod build_support {
    #[path = "catalog_gate.rs"]
    pub(crate) mod catalog_gate;
}

const FIXTURE_DEVELOPMENT_ENV: &str = "LANSPREAD_USE_FIXTURE_CATALOG";
const CATALOG_CONTENT_INDEX_NAME: &str = "catalog-content-index-v1.jsonl";
const EMBEDDED_CATALOG_INDEX_NAME: &str = "embedded-catalog-content-index-v1.jsonl";
const FIXTURE_MANIFEST_ROOT: &str = "../../lanspread-peer-cli/catalogs/default/manifests";

fn main() {
    println!("cargo:rerun-if-env-changed=TAURI_CONFIG");
    println!("cargo:rerun-if-env-changed={FIXTURE_DEVELOPMENT_ENV}");
    println!("cargo:rerun-if-changed=tauri.conf.json");
    println!("cargo:rerun-if-changed=game.db");
    println!("cargo:rerun-if-changed=manifests");

    let mode = catalog_build_mode().unwrap_or_else(|error| {
        panic!("catalog packaging policy failed: {error}");
    });
    if mode == CatalogBuildMode::Production
        && let Err(error) = validate_production_catalog("game.db", "manifests")
    {
        panic!("production catalog authority gate failed: {error}");
    }
    embed_catalog_content_index(mode).unwrap_or_else(|error| {
        panic!("failed to embed catalog launch authority: {error}");
    });
    tauri_build::build();
}

fn embed_catalog_content_index(mode: CatalogBuildMode) -> Result<(), Box<dyn std::error::Error>> {
    let manifest_root = match mode {
        CatalogBuildMode::FixtureDevelopment => Path::new(FIXTURE_MANIFEST_ROOT),
        CatalogBuildMode::Production => Path::new("manifests"),
    };
    let source = manifest_root.join(CATALOG_CONTENT_INDEX_NAME);
    println!("cargo:rerun-if-changed={}", source.display());
    let bytes = fs::read(&source)?;
    let out_dir =
        env::var_os("OUT_DIR").ok_or_else(|| std::io::Error::other("OUT_DIR is not set"))?;
    let output = PathBuf::from(out_dir).join(EMBEDDED_CATALOG_INDEX_NAME);
    fs::write(output, bytes)?;
    Ok(())
}

fn catalog_build_mode() -> Result<CatalogBuildMode, Box<dyn std::error::Error>> {
    let base_config = fs::read_to_string("tauri.conf.json")?;
    let config_override = env::var_os("TAURI_CONFIG")
        .map(|value| {
            value
                .into_string()
                .map_err(|_| "TAURI_CONFIG is not valid UTF-8".to_owned())
        })
        .transpose()?;
    let fixture_development_opt_in = match env::var_os(FIXTURE_DEVELOPMENT_ENV) {
        None => false,
        Some(value) if value == "1" => true,
        Some(_) => {
            return Err(format!("{FIXTURE_DEVELOPMENT_ENV} must be exactly 1 when set").into());
        }
    };
    let cargo_profile = env::var("PROFILE").ok();
    let out_dir = env::var_os("OUT_DIR").map(std::path::PathBuf::from);

    select_catalog_build_mode(CatalogGateInput {
        base_config: &base_config,
        config_override: config_override.as_deref(),
        fixture_development_opt_in,
        cargo_profile: cargo_profile.as_deref(),
        out_dir: out_dir.as_deref(),
    })
    .map_err(Into::into)
}