From d994e741b1df02720c1ff50a65978400a39ee72c Mon Sep 17 00:00:00 2001
From: ddidderr <ddidderr@paul.network>
Date: Wed, 12 Nov 2025 22:29:00 +0100
Subject: [PATCH] early error on peer's failure to determine file size

---
 crates/lanspread-peer/src/lib.rs  | 63 +++++++++++++++++++++++++++++--
 crates/lanspread-proto/src/lib.rs |  1 +
 2 files changed, 61 insertions(+), 3 deletions(-)

diff --git a/crates/lanspread-peer/src/lib.rs b/crates/lanspread-peer/src/lib.rs
index a2a7e7a..6b3d264 100644
--- a/crates/lanspread-peer/src/lib.rs
+++ b/crates/lanspread-peer/src/lib.rs
@@ -38,6 +38,45 @@ use crate::{
     peer::{send_game_file_chunk, send_game_file_data},
 };
 
+/// Custom error types for peer operations
+#[derive(Debug)]
+pub enum PeerError {
+    FileSizeDetermination {
+        path: String,
+        source: std::io::Error,
+    },
+    GameDirNotSet,
+    Other(eyre::Report),
+}
+
+impl std::fmt::Display for PeerError {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        match self {
+            PeerError::FileSizeDetermination { path, source } => {
+                write!(f, "Failed to determine file size for {path}: {source}")
+            }
+            PeerError::GameDirNotSet => write!(f, "Game directory not set"),
+            PeerError::Other(err) => write!(f, "General error: {err}"),
+        }
+    }
+}
+
+impl std::error::Error for PeerError {
+    fn source(&self) -> Option<&(dyn std::error::Error + 'static)> {
+        match self {
+            PeerError::FileSizeDetermination { source, .. } => Some(source),
+            PeerError::Other(err) => Some(err.root_cause()),
+            PeerError::GameDirNotSet => None,
+        }
+    }
+}
+
+impl From<eyre::Report> for PeerError {
+    fn from(err: eyre::Report) -> Self {
+        PeerError::Other(err)
+    }
+}
+
 /// Initialize and start the peer system
 /// This function replaces the main.rs entry point and allows the peer to be started from other crates
 pub fn start_peer(
@@ -1489,6 +1528,15 @@ async fn handle_peer_stream(
                                             id,
                                             file_descriptions,
                                         },
+                                        Err(PeerError::FileSizeDetermination { path, source }) => {
+                                            let error_msg = format!(
+                                                "Failed to determine file size for {path}: {source}"
+                                            );
+                                            log::error!(
+                                                "File size determination error for game {id}: {error_msg}"
+                                            );
+                                            Response::InternalPeerError(error_msg)
+                                        }
                                         Err(e) => {
                                             log::error!(
                                                 "Failed to get game file descriptions for {id}: {e}"
@@ -1754,6 +1802,9 @@ async fn request_game_details_from_peer(
         Response::GameNotFound(_) => {
             eyre::bail!("peer {peer_addr} does not have game {game_id}")
         }
+        Response::InternalPeerError(error_msg) => {
+            eyre::bail!("peer {peer_addr} reported internal error: {error_msg}")
+        }
         _ => eyre::bail!("unexpected response from {peer_addr}: {response:?}"),
     }
 }
@@ -1855,12 +1906,15 @@ async fn ping_peer(peer_addr: SocketAddr) -> eyre::Result<bool> {
 async fn get_game_file_descriptions(
     game_id: &str,
     game_dir: &str,
-) -> eyre::Result<Vec<GameFileDescription>> {
+) -> Result<Vec<GameFileDescription>, PeerError> {
     let base_dir = PathBuf::from(game_dir);
     let game_path = base_dir.join(game_id);
 
     if !game_path.exists() {
-        eyre::bail!("Game directory does not exist: {}", game_path.display());
+        return Err(PeerError::Other(eyre::eyre!(
+            "Game directory does not exist: {}",
+            game_path.display()
+        )));
     }
 
     let mut file_descriptions = Vec::new();
@@ -1889,7 +1943,10 @@ async fn get_game_file_descriptions(
                 Ok(metadata) => metadata.len(),
                 Err(e) => {
                     log::error!("Failed to read metadata for {relative_path}: {e}");
-                    eyre::bail!("Failed to read metadata for {relative_path}: {e}");
+                    return Err(PeerError::FileSizeDetermination {
+                        path: relative_path.clone(),
+                        source: e,
+                    });
                 }
             }
         };
diff --git a/crates/lanspread-proto/src/lib.rs b/crates/lanspread-proto/src/lib.rs
index 9ae1375..3e45192 100644
--- a/crates/lanspread-proto/src/lib.rs
+++ b/crates/lanspread-proto/src/lib.rs
@@ -31,6 +31,7 @@ pub enum Response {
     InvalidRequest(Bytes, String),
     EncodingError(String),
     DecodingError(Bytes, String),
+    InternalPeerError(String),
 }
 
 // Add Message trait