feat: add debounced session autosave

1 files changed, 75 insertions, 21 deletions

diff --git a/src/persist.rs b/src/persist.rs
index ccb44ace..6704dd17 100644
--- a/src/persist.rs
+++ b/src/persist.rs
@@ -487,36 +487,46 @@ fn session_path() -> PathBuf {
     crate::config::config_dir().join("session.json")
 }
 
-pub fn save(snapshot: &SessionSnapshot) {
-    let path = session_path();
+fn save_to_path(path: &std::path::Path, snapshot: &SessionSnapshot) -> std::io::Result<()> {
     if let Some(parent) = path.parent() {
-        if let Err(e) = std::fs::create_dir_all(parent) {
-            error!(err = %e, "failed to create session directory");
-            return;
-        }
+        std::fs::create_dir_all(parent)?;
     }
-    let json = match serde_json::to_string_pretty(snapshot) {
-        Ok(j) => j,
-        Err(e) => {
-            error!(err = %e, "failed to serialize session");
-            return;
-        }
-    };
-    // Atomic write: write to temp file, then rename
+    let json = serde_json::to_string_pretty(snapshot)?;
     let tmp_path = path.with_extension("json.tmp");
-    if let Err(e) = std::fs::write(&tmp_path, &json) {
-        error!(err = %e, "failed to write session temp file");
-        return;
-    }
-    if let Err(e) = std::fs::rename(&tmp_path, &path) {
-        error!(err = %e, "failed to rename session file");
-        // Clean up temp file
+    std::fs::write(&tmp_path, &json)?;
+    if let Err(err) = std::fs::rename(&tmp_path, path) {
         let _ = std::fs::remove_file(&tmp_path);
+        return Err(err);
+    }
+    Ok(())
+}
+
+fn clear_path(path: &std::path::Path) -> std::io::Result<()> {
+    match std::fs::remove_file(path) {
+        Ok(()) => Ok(()),
+        Err(err) if err.kind() == std::io::ErrorKind::NotFound => Ok(()),
+        Err(err) => Err(err),
+    }
+}
+
+pub fn save(snapshot: &SessionSnapshot) {
+    let path = session_path();
+    if let Err(err) = save_to_path(&path, snapshot) {
+        error!(err = %err, path = %path.display(), "failed to save session");
         return;
     }
     info!(workspaces = snapshot.workspaces.len(), "session saved");
 }
 
+pub fn clear() {
+    let path = session_path();
+    if let Err(err) = clear_path(&path) {
+        error!(err = %err, path = %path.display(), "failed to clear session");
+        return;
+    }
+    info!(path = %path.display(), "session cleared");
+}
+
 fn parse_snapshot(content: &str) -> Result<SessionSnapshot, String> {
     let raw = serde_json::from_str::<RawSessionSnapshot>(content).map_err(|e| e.to_string())?;
     if raw.version > SNAPSHOT_VERSION {
@@ -583,6 +593,19 @@ mod tests {
         }
     }
 
+    fn temp_session_path(name: &str) -> PathBuf {
+        let unique = format!(
+            "herdr-session-tests-{}-{}-{}",
+            name,
+            std::process::id(),
+            std::time::SystemTime::now()
+                .duration_since(std::time::UNIX_EPOCH)
+                .unwrap()
+                .as_nanos()
+        );
+        std::env::temp_dir().join(unique).join("session.json")
+    }
+
     #[test]
     fn round_trip_empty_session() {
         let snap = SessionSnapshot {
@@ -603,6 +626,37 @@ mod tests {
     }
 
     #[test]
+    fn clear_path_removes_existing_session_file() {
+        let path = temp_session_path("clear-existing");
+        save_to_path(
+            &path,
+            &SessionSnapshot {
+                version: SNAPSHOT_VERSION,
+                workspaces: vec![],
+                active: None,
+                selected: 0,
+                agent_panel_scope: AgentPanelScope::CurrentWorkspace,
+                sidebar_width: Some(26),
+                sidebar_section_split: Some(0.5),
+            },
+        )
+        .unwrap();
+
+        clear_path(&path).unwrap();
+
+        assert!(!path.exists());
+    }
+
+    #[test]
+    fn clear_path_ignores_missing_session_file() {
+        let path = temp_session_path("clear-missing");
+
+        clear_path(&path).unwrap();
+
+        assert!(!path.exists());
+    }
+
+    #[test]
     fn round_trip_layout_snapshot() {
         let layout = LayoutSnapshot::Split {
             direction: DirectionSnapshot::Horizontal,