Documents:
- Complete session history and what was accomplished
- ACE → CodeMirror migration rationale and steps
- Flex layout height constraint fix pattern
- Key technical learnings (CJS/ESM interop, flex layouts)
- Remaining steps organized by priority (high/medium/low)
- Continuation prompt template for next session
- MVP success criteria (all ✅ complete)
This serves as the handoff document for the next developer
or AI agent continuing work on User Mode.
Documents the complete ACE → CodeMirror migration, including:
- Root cause analysis of react-ace CJS/ESM incompatibility with Vite
- Migration steps and rationale for @uiw/react-codemirror
- Flex layout height constraint fix and the underlying pattern
- Key technical learnings about CJS/ESM interop and flex layouts
- Remaining steps and continuation prompt for next session
This serves as the authoritative reference for why we use CodeMirror
and how to properly constrain third-party components in flex layouts.
The editor was overflowing its container because @uiw/react-codemirror
renders a wrapper div that doesn't inherit flex constraints by default.
Fixed by adding CSS rules that:
1. Set overflow:hidden on .cm-editor-container
2. Target the wrapper div (> div) with flex:1, min-height:0, overflow:hidden
3. Set .cm-editor and .cm-scroller to overflow appropriately
This ensures the flex height constraint propagates through every level
of the CodeMirror DOM tree, and only .cm-scroller scrolls.
Layout chain:
.cm-editor-container (flex-1, min-h-0)
└─ wrapper div (flex:1, min-h-0, overflow:hidden)
└─ .cm-editor (flex:1, min-h-0, overflow:hidden)
└─ .cm-scroller (min-h-0, overflow:auto) ← only this scrolls
react-ace v14 is CommonJS-only with no ESM entry point, making it
fundamentally incompatible with Vite's ESM-first dev server. Every
CJS interop workaround failed. Switched to @uiw/react-codemirror v4.25
which ships proper dual ESM+CJS and works with Vite out of the box.
Changes:
- Remove ace-builds and react-ace dependencies
- Add @uiw/react-codemirror + 16 @codemirror/lang-* packages
- Add @uiw/codemirror-theme-tomorrow-night-blue (closest to ACE's 'tomorrow')
- Add @replit/codemirror-lang-csharp for C# support
- Rewrite EditorPanel.tsx: delete 108 lines of ACE boilerplate
(?url imports, setModuleUrl, CJS interop hack), replace with
~30 lines of clean CodeMirror language extension setup
- Delete vite.d.ts (only needed for ACE ?url import types)
- Remove optimizeDeps.include from vite.config.ts (not needed for CM)
- Add CodeMirror flex layout CSS to index.css
Supported languages: JavaScript/JSX, TypeScript/TSX, Python, JSON,
HTML, CSS, Less, YAML, Markdown, SQL, Java, Go, Rust, C/C++, C#,
PHP, XML. Unsupported types fall back to plain text.
Verified: tsc clean, vite build passes, heartbeat worker intact.
react-ace v14 ships CommonJS only ('main': 'lib/index.js'). Vite's dev
server pre-bundling wraps CJS modules as namespace objects where the
default export is nested under .default. This caused 'Element type is
invalid: got object' because import Ace from 'react-ace' resolved to
the module namespace instead of the React component.
Fix: import * as ReactAceModule and extract default with fallback:
const Ace = ReactAceModule.default || ReactAceModule
Same treatment for ace-builds import. Production build (Rolldown) was
unaffected due to different CJS interop handling.
- Added react-ace and ace-builds to optimizeDeps.include
- This forces Vite to properly bundle the CommonJS react-ace module
- Resolves 'Element type is invalid' error when opening files
The react-ace package uses CommonJS exports, and Vite needs to
pre-bundle it to properly handle the default export in ESM context.
- Fixed Ace import (default import, not named)
- Moved EditorPanel from FilesPanel to ChatSessionView
- Editor now replaces chat view when file is selected (per UI design guide)
- FILES panel now contains only the file tree
- Added editorFilePath state to track open file
- File selection in tree opens editor in content area
- Close button returns to chat view
This matches the UI design guide specification where the File Editor
replaces the Chat View in the content area when a file is selected.
Root Cause: CSS flex items default to min-height: auto, which prevents
flex-1 elements from shrinking below their content size. This caused
the FilesPanel to grow beyond its allocated space when the file tree
had many entries, pushing content off-screen.
Changes:
- FilesPanel.tsx: Added min-h-0 to root div to override min-height: auto
This allows flex-1 to actually constrain height and enable scrolling
- FileTree.tsx: Removed redundant overflow-auto and h-full from root div
The parent (FilesPanel flex-1 overflow-auto) already handles scrolling.
Nested scroll containers create height resolution issues.
The sidebar layout is now a clean single-scroll-container hierarchy:
Sidebar (flex flex-col, no overflow)
↳ SESSION (shrink-0, natural height)
↳ PROJECT (shrink-0, natural height)
↳ FilesPanel (flex-1 min-h-0) — constrained to available space
↳ Header (natural height)
↳ Scroll area (flex-1 overflow-auto) — THE scroll container
↳ FileTree (p-2 only) — no overflow, no h-full
↳ Footer (natural height)
- SESSION and PROJECT panels now have shrink-0 to prevent them from
growing unbounded and pushing FILES panel off-screen
- FILES panel with flex-1 now properly fills remaining vertical space
- File tree scrolls in-place while SESSION/PROJECT stay fixed
- FileTree had flex-1 inside an overflow container which didn't work
- Changed to h-full to properly fill the parent container height
- Scrolling now works correctly in the file tree area
- The sidebar container had overflow-y-auto which caused the entire sidebar
to scroll when FILES panel content grew
- FILES panel already has proper flex-1 and internal overflow-auto handling
- Now only the file tree scrolls in place while SESSION and PROJECT panels
remain fixed as expected
- Fixes UX issue where entire sidebar would scroll vertically
- Add flex-1 to FilesPanel root div
- Sidebar is flex flex-col, FILES panel now grows to fill space
- SESSION and PROJECT panels remain natural height
- FILES panel expands into all remaining vertical space
This eliminates the gap below the FILES panel footer by making
the panel itself grow rather than just making the tree bigger.
- Remove max-h-80 constraint from FileTree
- FileTree uses flex-1 to expand and fill available space
- Panel now properly fills sidebar from top to bottom
- File tree scrolls internally when content overflows
The FILES panel header, file tree, and footer now form a proper
flex column that fills all remaining vertical space in the sidebar.
- Change FilesPanel overflow-hidden to overflow-auto for scrolling
- Add max-h-80 to FileTree to limit height while allowing scroll
- Add select-none to FileTreeNode to prevent text selection
- Cursor-pointer already present for clickable indication
Now the file tree scrolls independently within the FILES panel,
and text cannot be selected during rapid clicking.
CRITICAL FIX: Remove recursion from listDirectoryForTree function.
The backend was recursively fetching ALL subdirectories and returning
them as a flat list, which completely broke the lazy-loading model.
Changes:
- Remove recursive call in listDirectoryForTree
- Backend now returns ONLY immediate children
- Frontend handles lazy loading by requesting children on expand
- This matches the intended architecture where frontend controls tree
This fixes the issue where directory contents were duplicated and
the tree structure was corrupted when expanding/collapsing.
- Add debug logging to track project directory resolution
- Improve path traversal security check with proper separator handling
- Log entry count and first 10 entries for debugging
- Fix project root validation to prevent listing workspace root
The issue was that the tree was listing from the workspace root
(containing gadget-code/, gadget-drone/, packages/) instead of the
specific project directory. Added logging to help diagnose.
- Replace recursive buildTree with buildVisibleNodes approach
- Build flat list of visible nodes based on expanded state
- Use processNode helper to traverse tree structure correctly
- Each node appears exactly once in the rendered output
- Eliminates duplication when expanding directories
- Change buildTree from .map() to for-loop to properly render children
- Append expanded directory children to nodes array immediately
- Fix TypeScript error by using ReactElement instead of JSX.Element
- Children now render correctly when directories are expanded
- Create comprehensive plan document for agent instructions text area
- Define requirements, acceptance criteria, and technical implementation
- Include UI/UX mockups and testing strategy
- Plan discovered during FILES panel implementation
- Addresses need for project-specific acceptance criteria
Add end-to-end abort support: AbortSignal in @gadget/ai providers,
abortWorkOrder socket message, drone AbortController handling,
Cancel button and double-Esc in frontend, and aborted turn status display.
The Home icon in the PROJECT panel now navigates to /projects/{slug}
instead of /projects/{id}. This opens Project Manager with the
project already selected and displayed.
Adds type definitions + forwarding for status, reconnect_attempt, reconnect_failed, reconnect events.
Frontend build now runs tsc --noEmit before vite build so undefined socket events cause failures.
Fixes pre-existing type errors exposed by strict mode in the frontend.
- Switch frontend sign-in to /api/v1/auth/sign-in endpoint (includes persona)
- Add updateUser() to App context for proper state management
- Fix Settings.tsx save flow to use updateUser() instead of broken localStorage merge
- Remove unused web AuthController (gadget-code/src/controllers/auth.ts)
- Fix UserApiControllerV1 to return flat user object instead of double-wrapped
- Remove SessionType enum and references (dead code)
- Add proper server sign-out call before clearing local state
Resolves issue where User Settings view didn't display persona text even though it existed in the database.
The persona field was missing from both the session object and the API
response during sign-in, causing User Settings to display an empty field
even when the user had a persona defined in the database.
1. Vite config: make HTTPS conditional on SSL cert/key files existing
(pre-existing issue, broke builds when certs not present)
2. Drone reconnect handler: use socket.io Manager-level 'reconnect'
event (this.socket.io.on) instead of Socket-level event, and add
explicit type annotation for attemptNumber parameter
This commit addresses two interrelated issues causing drones to
de-register and users to be forcibly signed out:
## Heartbeat Timeout Fixes
1. Move heartbeat interval to a Web Worker (not subject to browser
tab throttling). Chrome throttles setInterval in background tabs
to ~1/min, which causes the 19s heartbeat to miss the drone's
timeout timer. The Web Worker fires reliably regardless of tab
visibility.
2. Add visibilitychange handler: when the tab becomes visible again,
send an immediate heartbeat to reset the drone's timer after any
throttling that may have occurred.
3. Fix onReleaseSessionLock to clear the heartbeat timer. Previously,
releasing the lock left the 60s timer running, causing a spurious
timeout and status emit after the lock was already released.
4. Increase drone heartbeat timeout from 60s to 120s. With the Web
Worker fix, heartbeats should be reliable, but doubling the timeout
provides a generous safety margin.
5. Add socket disconnect/reconnect handlers on the drone side. On
disconnect, clear the heartbeat timer. On reconnect, re-emit drone
status so the platform knows the drone is alive.
6. Configure Socket.IO pingInterval/pingTimeout explicitly (25s/60s)
instead of relying on defaults.
## JWT Expiration Fixes
1. Increase WebToken DB record expiration from 1 hour to 7 days. The
1-hour expiration was the real session lifetime gate (the JWT crypto
exp was already 24h), and it was far too aggressive for a dev tool.
2. Fix web /auth/renew-token endpoint to use req.user from the session
cookie instead of verifyJsonWebToken(req.body.token). This eliminates
the catch-22 where an expired token cannot be used to request its
own renewal.
3. Fix token refresh response parsing. The API v1 renew-token endpoint
returns { success: true, token } at the top level, but the frontend
was looking for json.data?.token, causing every refresh to fail.
4. Add proactive token refresh: check the JWT exp claim before each
request and refresh if expiring within 5 minutes. This avoids
unnecessary 401 errors and the resulting socket disconnections.
5. Update socket JWT on token renewal via a callback registered in
App.tsx. This ensures that future socket reconnections use the new
token instead of the expired one.
## Files Modified
- gadget-code/frontend/src/workers/heartbeat.worker.ts (NEW)
- gadget-code/frontend/src/lib/socket.ts
- gadget-code/frontend/src/lib/api.ts
- gadget-code/frontend/src/App.tsx
- gadget-code/src/services/session.ts
- gadget-code/src/controllers/auth.ts
- gadget-code/src/services/socket.ts
- gadget-drone/src/gadget-drone.ts
