Merge remote-tracking branch 'upstream/friel/auto-unarchive-resume' into friel/auto-unarchive-resume

# Conflicts:
#	codex-rs/core/src/guardian/tests.rs
#	codex-rs/tui/src/chatwidget/tests.rs

codex-rs/app-server/src/codex_message_processor.rs

@@ -215,6 +215,7 @@ use codex_core::exec::ExecExpiration;
 use codex_core::exec::ExecParams;
 use codex_core::exec_env::create_env;
 use codex_core::find_archived_thread_path_by_id_str;
+use codex_core::find_or_unarchive_thread_path_by_id_str;
 use codex_core::find_thread_name_by_id;
 use codex_core::find_thread_names_by_ids;
 use codex_core::find_thread_path_by_id_str;
@@ -3882,7 +3883,7 @@ impl CodexMessageProcessor {
                 if path.exists() {
                     path
                 } else {
-                    match find_thread_path_by_id_str(
+                    match find_or_unarchive_thread_path_by_id_str(
                         &self.config.codex_home,
                         &existing_thread_id.to_string(),
                     )
@@ -3908,7 +3909,7 @@ impl CodexMessageProcessor {
                     }
                 }
             } else {
-                match find_thread_path_by_id_str(
+                match find_or_unarchive_thread_path_by_id_str(
                     &self.config.codex_home,
                     &existing_thread_id.to_string(),
                 )
@@ -4066,7 +4067,7 @@ impl CodexMessageProcessor {
                 }
             };
 
-            match find_thread_path_by_id_str(
+            match find_or_unarchive_thread_path_by_id_str(
                 &self.config.codex_home,
                 &existing_thread_id.to_string(),
             )

codex-rs/app-server/tests/suite/v2/thread_resume.rs

@@ -274,6 +274,62 @@ async fn thread_resume_returns_rollout_history() -> Result<()> {
     Ok(())
 }
 
+#[tokio::test]
+async fn thread_resume_unarchives_archived_rollout() -> Result<()> {
+    let server = create_mock_responses_server_repeating_assistant("Done").await;
+    let codex_home = TempDir::new()?;
+    create_config_toml(codex_home.path(), &server.uri())?;
+
+    let filename_ts = "2025-01-05T12-00-00";
+    let conversation_id = create_fake_rollout_with_text_elements(
+        codex_home.path(),
+        filename_ts,
+        "2025-01-05T12:00:00Z",
+        "Saved user message",
+        Vec::new(),
+        Some("mock_provider"),
+        /*git_info*/ None,
+    )?;
+    let active_rollout_path = rollout_path(codex_home.path(), filename_ts, &conversation_id);
+    let archived_rollout_path = codex_home.path().join("archived_sessions/2025/01/05").join(
+        active_rollout_path
+            .file_name()
+            .expect("active rollout file name"),
+    );
+    std::fs::create_dir_all(
+        archived_rollout_path
+            .parent()
+            .expect("archived rollout parent directory"),
+    )?;
+    std::fs::rename(&active_rollout_path, &archived_rollout_path)?;
+
+    let mut mcp = McpProcess::new(codex_home.path()).await?;
+    timeout(DEFAULT_READ_TIMEOUT, mcp.initialize()).await??;
+
+    let resume_id = mcp
+        .send_thread_resume_request(ThreadResumeParams {
+            thread_id: conversation_id.clone(),
+            ..Default::default()
+        })
+        .await?;
+    let resume_resp: JSONRPCResponse = timeout(
+        DEFAULT_READ_TIMEOUT,
+        mcp.read_stream_until_response_message(RequestId::Integer(resume_id)),
+    )
+    .await??;
+    let ThreadResumeResponse { thread, .. } = to_response::<ThreadResumeResponse>(resume_resp)?;
+
+    assert_eq!(thread.id, conversation_id);
+    assert!(active_rollout_path.exists());
+    assert!(!archived_rollout_path.exists());
+    assert_eq!(
+        std::fs::canonicalize(thread.path.as_ref().expect("thread path"))?,
+        std::fs::canonicalize(&active_rollout_path)?
+    );
+
+    Ok(())
+}
+
 #[tokio::test]
 async fn thread_resume_prefers_persisted_git_metadata_for_local_threads() -> Result<()> {
     let server = create_mock_responses_server_repeating_assistant("Done").await;

codex-rs/core/src/lib.rs

@@ -170,6 +170,7 @@ pub use rollout::append_thread_name;
 pub use rollout::find_archived_thread_path_by_id_str;
 #[deprecated(note = "use find_thread_path_by_id_str")]
 pub use rollout::find_conversation_path_by_id_str;
+pub use rollout::find_or_unarchive_thread_path_by_id_str;
 pub use rollout::find_thread_name_by_id;
 pub use rollout::find_thread_path_by_id_str;
 pub use rollout::find_thread_path_by_name_str;

codex-rs/core/src/rollout.rs

@@ -9,6 +9,7 @@ pub use codex_rollout::append_thread_name;
 pub use codex_rollout::find_archived_thread_path_by_id_str;
 #[deprecated(note = "use find_thread_path_by_id_str")]
 pub use codex_rollout::find_conversation_path_by_id_str;
+pub use codex_rollout::find_or_unarchive_thread_path_by_id_str;
 pub use codex_rollout::find_thread_name_by_id;
 pub use codex_rollout::find_thread_path_by_id_str;
 pub use codex_rollout::find_thread_path_by_name_str;

codex-rs/core/tests/suite/rollout_list_find.rs

@@ -9,6 +9,7 @@ use codex_core::RolloutRecorder;
 use codex_core::RolloutRecorderParams;
 use codex_core::config::ConfigBuilder;
 use codex_core::find_archived_thread_path_by_id_str;
+use codex_core::find_or_unarchive_thread_path_by_id_str;
 use codex_core::find_thread_path_by_id_str;
 use codex_core::find_thread_path_by_name_str;
 use codex_protocol::ThreadId;
@@ -219,3 +220,77 @@ async fn find_archived_locates_rollout_file_by_id() {
 
     assert_eq!(found, Some(expected));
 }
+
+#[tokio::test]
+async fn find_thread_path_by_id_str_does_not_unarchive_archived_rollout() {
+    let home = TempDir::new().unwrap();
+    let id = Uuid::new_v4();
+    let archived = write_minimal_rollout_with_id_in_subdir(home.path(), "archived_sessions", id);
+
+    let found = find_thread_path_by_id_str(home.path(), &id.to_string())
+        .await
+        .unwrap();
+
+    assert_eq!(found, None);
+    assert!(archived.exists());
+}
+
+#[tokio::test]
+async fn find_or_unarchive_restores_archived_rollout_file_by_id() {
+    let home = TempDir::new().unwrap();
+    let id = Uuid::new_v4();
+    let archived = write_minimal_rollout_with_id_in_subdir(home.path(), "archived_sessions", id);
+    let file_name = archived.file_name().unwrap().to_owned();
+    let expected_restored = home.path().join("sessions/2024/01/01").join(file_name);
+
+    let found = find_or_unarchive_thread_path_by_id_str(home.path(), &id.to_string())
+        .await
+        .unwrap();
+
+    assert_eq!(found, Some(expected_restored.clone()));
+    assert!(expected_restored.exists());
+    assert!(!archived.exists());
+
+    let archived_found = find_archived_thread_path_by_id_str(home.path(), &id.to_string())
+        .await
+        .unwrap();
+    assert_eq!(archived_found, None);
+}
+
+#[tokio::test]
+async fn find_does_not_move_unrelated_file_for_stale_archived_db_path() {
+    let home = TempDir::new().unwrap();
+    let requested_id = Uuid::new_v4();
+    let requested_thread_id = ThreadId::from_string(&requested_id.to_string()).unwrap();
+    let unrelated_id = Uuid::new_v4();
+    let unrelated_active_path = write_minimal_rollout_with_id(home.path(), unrelated_id);
+
+    upsert_thread_metadata(
+        home.path(),
+        requested_thread_id,
+        unrelated_active_path.clone(),
+    )
+    .await;
+    let runtime = StateRuntime::init(home.path().to_path_buf(), "test-provider".to_string())
+        .await
+        .unwrap();
+    runtime
+        .mark_backfill_complete(/*last_watermark*/ None)
+        .await
+        .unwrap();
+    runtime
+        .mark_archived(
+            requested_thread_id,
+            unrelated_active_path.as_path(),
+            Utc::now(),
+        )
+        .await
+        .unwrap();
+
+    let found = find_or_unarchive_thread_path_by_id_str(home.path(), &requested_id.to_string())
+        .await
+        .unwrap();
+
+    assert_eq!(found, None);
+    assert!(unrelated_active_path.exists());
+}

codex-rs/rollout/src/lib.rs

@@ -33,6 +33,7 @@ pub use codex_protocol::protocol::SessionMeta;
 pub use config::RolloutConfig;
 pub use config::RolloutConfigView;
 pub use list::find_archived_thread_path_by_id_str;
+pub use list::find_or_unarchive_thread_path_by_id_str;
 pub use list::find_thread_path_by_id_str;
 #[deprecated(note = "use find_thread_path_by_id_str")]
 pub use list::find_thread_path_by_id_str as find_conversation_path_by_id_str;

codex-rs/rollout/src/list.rs

@@ -1246,9 +1246,97 @@ async fn find_thread_path_by_id_str_in_subdir(
     Ok(found)
 }
 
-/// Locate a recorded thread rollout file by its UUID string using the existing
-/// paginated listing implementation. Returns `Ok(Some(path))` if found, `Ok(None)` if not present
-/// or the id is invalid.
+async fn try_unarchive_thread_path_by_id_str(
+    codex_home: &Path,
+    id_str: &str,
+) -> io::Result<Option<PathBuf>> {
+    let Ok(requested_id) = Uuid::parse_str(id_str) else {
+        return Ok(None);
+    };
+    let Some(archived_path) =
+        find_thread_path_by_id_str_in_subdir(codex_home, ARCHIVED_SESSIONS_SUBDIR, id_str).await?
+    else {
+        return Ok(None);
+    };
+    let archived_root = codex_home.join(ARCHIVED_SESSIONS_SUBDIR);
+    if archived_path.strip_prefix(&archived_root).is_err() {
+        tracing::error!(
+            "archived rollout candidate for thread {id_str} is not under {}: {}",
+            archived_root.display(),
+            archived_path.display()
+        );
+        return Ok(None);
+    }
+
+    let Some(file_name) = archived_path.file_name().map(OsStr::to_owned) else {
+        tracing::error!(
+            "archived rollout path for thread {id_str} missing file name: {}",
+            archived_path.display()
+        );
+        return Ok(None);
+    };
+    let file_name_str = file_name.to_string_lossy();
+    let Some((_created_at, file_id)) = parse_timestamp_uuid_from_filename(&file_name_str) else {
+        tracing::error!(
+            "archived rollout path for thread {id_str} has invalid rollout filename: {}",
+            archived_path.display()
+        );
+        return Ok(None);
+    };
+    if file_id != requested_id {
+        tracing::error!(
+            "archived rollout path for thread {id_str} has mismatched rollout filename: {}",
+            archived_path.display()
+        );
+        return Ok(None);
+    }
+    let Some((year, month, day)) = rollout_date_parts(&file_name) else {
+        tracing::error!(
+            "archived rollout path for thread {id_str} missing filename timestamp: {}",
+            archived_path.display()
+        );
+        return Ok(None);
+    };
+
+    let restored_dir = codex_home
+        .join(SESSIONS_SUBDIR)
+        .join(year)
+        .join(month)
+        .join(day);
+    tokio::fs::create_dir_all(&restored_dir).await?;
+    let restored_path = restored_dir.join(&file_name);
+    match tokio::fs::rename(&archived_path, &restored_path).await {
+        Ok(()) => {}
+        Err(err) => {
+            if tokio::fs::try_exists(&restored_path).await.unwrap_or(false) {
+                tracing::debug!(
+                    "archived rollout for thread {id_str} already restored concurrently to {}",
+                    restored_path.display()
+                );
+            } else {
+                return Err(err);
+            }
+        }
+    }
+
+    if let Some(state_db_ctx) = state_db::open_if_present(codex_home, "").await
+        && let Ok(thread_id) = ThreadId::from_string(id_str)
+    {
+        let _ = state_db_ctx
+            .mark_unarchived(thread_id, restored_path.as_path())
+            .await;
+    }
+
+    Ok(Some(restored_path))
+}
+
+/// Locate a recorded active thread rollout file by its UUID string using the existing paginated
+/// listing implementation.
+///
+/// This helper intentionally has no side effects. Callers that want "resume and restore from
+/// archive if needed" semantics must opt in with [`find_or_unarchive_thread_path_by_id_str`] so
+/// that other lookup paths (for example fork-reference resolution) do not silently move archived
+/// rollouts back into `sessions/`.
 pub async fn find_thread_path_by_id_str(
     codex_home: &Path,
     id_str: &str,
@@ -1256,6 +1344,18 @@ pub async fn find_thread_path_by_id_str(
     find_thread_path_by_id_str_in_subdir(codex_home, SESSIONS_SUBDIR, id_str).await
 }
 
+/// Locate a thread rollout file by UUID string, restoring it from `archived_sessions/` when
+/// needed for resume flows.
+pub async fn find_or_unarchive_thread_path_by_id_str(
+    codex_home: &Path,
+    id_str: &str,
+) -> io::Result<Option<PathBuf>> {
+    if let Some(active_path) = find_thread_path_by_id_str(codex_home, id_str).await? {
+        return Ok(Some(active_path));
+    }
+    try_unarchive_thread_path_by_id_str(codex_home, id_str).await
+}
+
 /// Locate an archived thread rollout file by its UUID string.
 pub async fn find_archived_thread_path_by_id_str(
     codex_home: &Path,