feat: add file autocomplete for @ mentions

Author: Dimillian

src-tauri/src/lib.rs

@@ -49,6 +49,53 @@ fn normalize_git_path(path: &str) -> String {
     path.replace('\\', "/")
 }
 
+fn should_skip_dir(name: &str) -> bool {
+    matches!(
+        name,
+        ".git" | "node_modules" | "dist" | "target" | "release-artifacts"
+    )
+}
+
+fn list_workspace_files_inner(root: &PathBuf, max_files: usize) -> Vec<String> {
+    let mut results = Vec::new();
+    let mut stack = vec![root.clone()];
+
+    while let Some(dir) = stack.pop() {
+        let entries = match std::fs::read_dir(&dir) {
+            Ok(entries) => entries,
+            Err(_) => continue,
+        };
+        for entry in entries.flatten() {
+            let path = entry.path();
+            let file_name = entry
+                .file_name()
+                .to_string_lossy()
+                .to_string();
+            if path.is_dir() {
+                if should_skip_dir(&file_name) {
+                    continue;
+                }
+                stack.push(path);
+                continue;
+            }
+            if path.is_file() {
+                if let Ok(rel_path) = path.strip_prefix(root) {
+                    let normalized = normalize_git_path(&rel_path.to_string_lossy());
+                    if !normalized.is_empty() {
+                        results.push(normalized);
+                    }
+                }
+            }
+            if results.len() >= max_files {
+                return results;
+            }
+        }
+    }
+
+    results.sort();
+    results
+}
+
 fn diff_stats_for_path(
     repo: &Repository,
     head_tree: Option<&Tree>,
@@ -1014,6 +1061,19 @@ async fn get_git_remote(
     Ok(remote.url().map(|url| url.to_string()))
 }
 
+#[tauri::command]
+async fn list_workspace_files(
+    workspace_id: String,
+    state: State<'_, AppState>,
+) -> Result<Vec<String>, String> {
+    let workspaces = state.workspaces.lock().await;
+    let entry = workspaces
+        .get(&workspace_id)
+        .ok_or("workspace not found")?;
+    let root = PathBuf::from(&entry.path);
+    Ok(list_workspace_files_inner(&root, 20000))
+}
+
 #[cfg_attr(mobile, tauri::mobile_entry_point)]
 pub fn run() {
     tauri::Builder::default()
@@ -1141,6 +1201,7 @@ pub fn run() {
             get_git_diffs,
             get_git_log,
             get_git_remote,
+            list_workspace_files,
             model_list,
             account_rate_limits,
             skills_list

src/App.tsx

@@ -40,6 +40,7 @@ import { useGitLog } from "./hooks/useGitLog";
 import { useGitRemote } from "./hooks/useGitRemote";
 import { useModels } from "./hooks/useModels";
 import { useSkills } from "./hooks/useSkills";
+import { useWorkspaceFiles } from "./hooks/useWorkspaceFiles";
 import { useDebugLog } from "./hooks/useDebugLog";
 import { useWorkspaceRefreshOnFocus } from "./hooks/useWorkspaceRefreshOnFocus";
 import { useWorkspaceRestore } from "./hooks/useWorkspaceRestore";
@@ -139,6 +140,7 @@ function MainApp() {
     setSelectedEffort,
   } = useModels({ activeWorkspace, onDebug: addDebugEntry });
   const { skills } = useSkills({ activeWorkspace, onDebug: addDebugEntry });
+  const { files } = useWorkspaceFiles({ activeWorkspace, onDebug: addDebugEntry });
 
   const resolvedModel = selectedModel?.model ?? null;
   const fileStatus =
@@ -494,6 +496,7 @@ function MainApp() {
       accessMode={accessMode}
       onSelectAccessMode={setAccessMode}
       skills={skills}
+      files={files}
     />
   ) : null;
 

src/components/Composer.tsx

@@ -19,6 +19,7 @@ type ComposerProps = {
   accessMode: "read-only" | "current" | "full-access";
   onSelectAccessMode: (mode: "read-only" | "current" | "full-access") => void;
   skills: { name: string; description?: string }[];
+  files: string[];
   contextUsage?: ThreadTokenUsage | null;
   queuedMessages?: QueuedMessage[];
   onEditQueued?: (item: QueuedMessage) => void;
@@ -42,6 +43,7 @@ export function Composer({
   accessMode,
   onSelectAccessMode,
   skills,
+  files,
   contextUsage = null,
   queuedMessages = [],
   onEditQueued,
@@ -80,6 +82,7 @@ export function Composer({
     selectionStart,
     disabled,
     skills,
+    files,
     textareaRef,
     setText,
     setSelectionStart,

src/components/ComposerInput.tsx

@@ -39,6 +39,13 @@ export function ComposerInput({
 }: ComposerInputProps) {
   const suggestionListRef = useRef<HTMLDivElement | null>(null);
   const suggestionRefs = useRef<Array<HTMLButtonElement | null>>([]);
+  const isFileSuggestion = (item: AutocompleteItem) =>
+    item.label.includes("/") || item.label.includes("\\");
+  const fileTitle = (path: string) => {
+    const normalized = path.replace(/\\/g, "/");
+    const parts = normalized.split("/").filter(Boolean);
+    return parts.length ? parts[parts.length - 1] : path;
+  };
 
   useEffect(() => {
     if (!suggestionsOpen) {
@@ -100,11 +107,24 @@ export function ComposerInput({
                 onClick={() => onSelectSuggestion(item)}
                 onMouseEnter={() => onHighlightIndex(index)}
               >
-                <span className="composer-suggestion-title">{item.label}</span>
-                {item.description && (
-                  <span className="composer-suggestion-description">
-                    {item.description}
-                  </span>
+                {isFileSuggestion(item) ? (
+                  <>
+                    <span className="composer-suggestion-title">
+                      {fileTitle(item.label)}
+                    </span>
+                    <span className="composer-suggestion-description">
+                      {item.label}
+                    </span>
+                  </>
+                ) : (
+                  <>
+                    <span className="composer-suggestion-title">{item.label}</span>
+                    {item.description && (
+                      <span className="composer-suggestion-description">
+                        {item.description}
+                      </span>
+                    )}
+                  </>
                 )}
               </button>
             ))}

src/hooks/useComposerAutocompleteState.ts

@@ -9,6 +9,7 @@ type UseComposerAutocompleteStateArgs = {
   selectionStart: number | null;
   disabled: boolean;
   skills: Skill[];
+  files: string[];
   textareaRef: React.RefObject<HTMLTextAreaElement | null>;
   setText: (next: string) => void;
   setSelectionStart: (next: number | null) => void;
@@ -19,6 +20,7 @@ export function useComposerAutocompleteState({
   selectionStart,
   disabled,
   skills,
+  files,
   textareaRef,
   setText,
   setSelectionStart,
@@ -34,9 +36,22 @@ export function useComposerAutocompleteState({
     [skills],
   );
 
+  const fileItems = useMemo<AutocompleteItem[]>(
+    () =>
+      files.map((path) => ({
+        id: path,
+        label: path,
+        insertText: path,
+      })),
+    [files],
+  );
+
   const triggers = useMemo(
-    () => [{ trigger: "$", items: skillItems }],
-    [skillItems],
+    () => [
+      { trigger: "$", items: skillItems },
+      { trigger: "@", items: fileItems },
+    ],
+    [fileItems, skillItems],
   );
 
   const {
@@ -58,19 +73,28 @@ export function useComposerAutocompleteState({
       if (!autocompleteRange) {
         return;
       }
-      const before = text.slice(0, autocompleteRange.start);
+      const triggerIndex = Math.max(0, autocompleteRange.start - 1);
+      const triggerChar = text[triggerIndex] ?? "";
+      const before =
+        triggerChar === "@"
+          ? text.slice(0, triggerIndex)
+          : text.slice(0, autocompleteRange.start);
       const after = text.slice(autocompleteRange.end);
       const insert = item.insertText ?? item.label;
+      const actualInsert = triggerChar === "@"
+        ? insert.replace(/^@+/, "")
+        : insert;
       const needsSpace = after.length === 0 ? true : !/^\s/.test(after);
-      const nextText = `${before}${insert}${needsSpace ? " " : ""}${after}`;
+      const nextText = `${before}${actualInsert}${needsSpace ? " " : ""}${after}`;
       setText(nextText);
       closeAutocomplete();
       requestAnimationFrame(() => {
         const textarea = textareaRef.current;
         if (!textarea) {
           return;
         }
-        const cursor = before.length + insert.length + (needsSpace ? 1 : 0);
+        const cursor =
+          before.length + actualInsert.length + (needsSpace ? 1 : 0);
         textarea.focus();
         textarea.setSelectionRange(cursor, cursor);
         setSelectionStart(cursor);

src/hooks/useWorkspaceFiles.ts

@@ -0,0 +1,76 @@
+import { useCallback, useEffect, useMemo, useRef, useState } from "react";
+import type { DebugEntry, WorkspaceInfo } from "../types";
+import { getWorkspaceFiles } from "../services/tauri";
+
+type UseWorkspaceFilesOptions = {
+  activeWorkspace: WorkspaceInfo | null;
+  onDebug?: (entry: DebugEntry) => void;
+};
+
+export function useWorkspaceFiles({
+  activeWorkspace,
+  onDebug,
+}: UseWorkspaceFilesOptions) {
+  const [files, setFiles] = useState<string[]>([]);
+  const lastFetchedWorkspaceId = useRef<string | null>(null);
+  const inFlight = useRef(false);
+
+  const workspaceId = activeWorkspace?.id ?? null;
+  const isConnected = Boolean(activeWorkspace?.connected);
+
+  const refreshFiles = useCallback(async () => {
+    if (!workspaceId || !isConnected) {
+      return;
+    }
+    if (inFlight.current) {
+      return;
+    }
+    inFlight.current = true;
+    onDebug?.({
+      id: `${Date.now()}-client-files-list`,
+      timestamp: Date.now(),
+      source: "client",
+      label: "files/list",
+      payload: { workspaceId },
+    });
+    try {
+      const response = await getWorkspaceFiles(workspaceId);
+      onDebug?.({
+        id: `${Date.now()}-server-files-list`,
+        timestamp: Date.now(),
+        source: "server",
+        label: "files/list response",
+        payload: response,
+      });
+      setFiles(Array.isArray(response) ? response : []);
+      lastFetchedWorkspaceId.current = workspaceId;
+    } catch (error) {
+      onDebug?.({
+        id: `${Date.now()}-client-files-list-error`,
+        timestamp: Date.now(),
+        source: "error",
+        label: "files/list error",
+        payload: error instanceof Error ? error.message : String(error),
+      });
+    } finally {
+      inFlight.current = false;
+    }
+  }, [isConnected, onDebug, workspaceId]);
+
+  useEffect(() => {
+    if (!workspaceId || !isConnected) {
+      return;
+    }
+    if (lastFetchedWorkspaceId.current === workspaceId && files.length > 0) {
+      return;
+    }
+    refreshFiles();
+  }, [files.length, isConnected, refreshFiles, workspaceId]);
+
+  const fileOptions = useMemo(() => files.filter(Boolean), [files]);
+
+  return {
+    files: fileOptions,
+    refreshFiles,
+  };
+}

src/services/tauri.ts

@@ -132,6 +132,10 @@ export async function getSkillsList(workspaceId: string) {
   return invoke<any>("skills_list", { workspaceId });
 }
 
+export async function getWorkspaceFiles(workspaceId: string) {
+  return invoke<string[]>("list_workspace_files", { workspaceId });
+}
+
 export async function listThreads(
   workspaceId: string,
   cursor?: string | null,