PHASE 2 DESIGN: RICH PROMPTS AND OUTPUT ENHANCEMENTS
======================================================

Overview
--------

Phase 1 delivered basic remote control: Claude Code session wrapping, SSE streaming
to mobile dashboard, binary prompt approval (y/n only). Phase 2 addresses the most
critical gaps between clarc and the crabigator reference implementation:

1. Rich prompt system - multi-option choices, text input, tab instructions
2. ANSI color parsing in output
3. Session statistics extraction and display
4. Git status widget
5. UI polish - style controls, filtering, auto-scroll

This phase transforms clarc from a proof-of-concept into a genuinely useful
remote approval tool. Priority is on prompt system (the blocker for real usage)
followed by output quality and UX improvements.


PROMPT SYSTEM REDESIGN
======================

The Current Problem
-------------------

Claude Code presents three types of interactive prompts:

1. Permission prompts - tool access requests with options like:
   - Yes (allow once)
   - Yes, and allow all future requests for this tool
   - No (deny)
   - Tab to add additional instructions

2. Question prompts - AskUserQuestion with multiple choice:
   - Numbered options (1, 2, 3...)
   - Optional "Other" text input
   - Sometimes multiple questions in sequence

3. Plan mode exit prompts - after plan generation:
   - Continue with plan
   - Modify plan
   - Cancel

Current implementation only sends "y\n" or "n\n" - unusable for real workflows.


Message Types Claude Code Emits
--------------------------------

Based on crabigator's events.rs, Claude Code hooks provide structured prompt data:

Permission prompt:
{
  "type": "prompt",
  "prompt": {
    "prompt_type": "permission",
    "tool_name": "Write",
    "tool_input": { "file_path": "/path/to/file.txt", "content": "..." },
    "options": [
      { "label": "Yes", "value": "1", "description": "Allow once" },
      { "label": "Yes, always", "value": "2", "description": "Allow all future" },
      { "label": "No", "value": "3", "description": "Deny" }
    ],
    "allows_tab_instructions": true,
    "selected_option": 1
  }
}

Question prompt:
{
  "type": "prompt",
  "prompt": {
    "prompt_type": "question",
    "questions": [
      {
        "question": "Which approach should I take?",
        "header": "Implementation choice",
        "options": [
          { "label": "Use SQLite", "value": "1" },
          { "label": "Use JSON files", "value": "2" }
        ],
        "multi_select": false,
        "allows_other": true
      }
    ]
  }
}

Exit plan prompt:
{
  "type": "prompt",
  "prompt": {
    "prompt_type": "exit_plan",
    "options": [
      { "label": "Continue with plan", "value": "1" },
      { "label": "Modify plan", "value": "2" },
      { "label": "Cancel", "value": "3" }
    ]
  }
}

Prompt cleared:
{
  "type": "prompt",
  "prompt": null
}


UI for Each Prompt Type
------------------------

Permission prompts:
- Show tool name and relevant input (file path, command, etc.)
- Radio button list of options (Yes / Yes always / No)
- Show which option is currently selected (from selected_option field)
- If allows_tab_instructions is true, show "Add instructions" button
- Instructions UI: textarea + submit button, sends key sequence:
  - Navigate to correct option if needed (up/down arrow keys)
  - Press Tab
  - Type instruction text
  - Press Enter

Question prompts:
- Show question header if present
- Show question text
- Radio button list for single-select, checkboxes for multi-select
- If allows_other is true, show "Other" option with text input
- Submit button sends option number(s) or text input

Exit plan prompts:
- Show plan context (last few lines of output mentioning the plan)
- Radio button list of options
- Submit button sends option number

General prompt UI patterns:
- Large touch targets for mobile (min 44px height)
- Clear visual distinction from regular output
- Show prompt at top of session card (sticky while scrolling output)
- Disable interaction if desktop disconnected
- Show loading state after submission
- Clear prompt UI when prompt clears (state change from permission/question to ready)


Response Protocol Changes
--------------------------

Current: POST /api/sessions/:id/approve with { approved: boolean }
Sends "y\n" or "n\n" to PTY

New: POST /api/sessions/:id/answer with { response: AnswerResponse }

Where AnswerResponse is one of:

Simple option selection:
{
  "type": "option",
  "value": "2"  // option number as string
}

Text input (for "Other" in questions):
{
  "type": "text",
  "value": "User's custom answer here"
}

Tab instructions (for permission prompts):
{
  "type": "tab_instructions",
  "selected_option": 1,  // which option to select first
  "instruction": "Only process files in the src/ directory"
}

Server processing:

- Option selection: write "${value}\n" to PTY (e.g., "2\n")
- Text input: write "${value}\n" to PTY
- Tab instructions: execute key sequence:
  1. Navigate to selected_option (send up/down arrows)
  2. Wait 100ms
  3. Send Tab key
  4. Wait 100ms
  5. Write instruction text
  6. Send Enter key

Key sequence execution needs pty.write() for text and special key codes:
- Up arrow: "\x1b[A"
- Down arrow: "\x1b[B"
- Tab: "\t"
- Enter: "\n"


OUTPUT IMPROVEMENTS
===================

ANSI Color Parsing
------------------

Current: plain text output, no colors
Needed: parse ANSI escape codes and render as HTML with colored spans

Crabigator uses ansi-to-html conversion in dashboard/js/ansi.ts. For Bun stack,
options:

1. Use ansi-to-html npm package (simple, proven)
2. Implement minimal parser (only need basic colors, not full xterm)
3. Use ansi-escapes to strip codes, add classes for common patterns

Recommendation: ansi-to-html package for phase 2, optimization later if needed

Implementation:
- Parse ANSI in server before sending via SSE
- Send HTML with spans: <span class="ansi-red">text</span>
- CSS classes map to terminal color palette
- Store raw ANSI in database, parse on read

CSS terminal colors:
.ansi-black { color: #000000; }
.ansi-red { color: #cd3131; }
.ansi-green { color: #0dbc79; }
.ansi-yellow { color: #e5e510; }
.ansi-blue { color: #2472c8; }
.ansi-magenta { color: #bc3fbc; }
.ansi-cyan { color: #11a8cd; }
.ansi-white { color: #e5e5e5; }
.ansi-bright-black { color: #666666; }
(etc. for full 16-color palette plus bold/italic/underline)


Session Stats Extraction
-------------------------

Claude Code emits stats via hooks. Need to parse and display:

- Prompts count (user interactions)
- Completions count (LLM responses)
- Tools count (tool invocations)
- Compressions count (context compaction events)
- Thinking time (cumulative seconds in thinking state)
- Work time (cumulative seconds in ready/thinking/busy states)
- Idle time (time since last activity)
- Current mode (normal / auto_accept / plan)
- Current model name (claude-opus-4-5-20251101, etc.)

Stats arrive via "stats" event type (see crabigator events.rs lines 199-275):

{
  "type": "stats",
  "prompts": 5,
  "completions": 3,
  "tools": 12,
  "compressions": 1,
  "thinking_seconds": 45,
  "work_seconds": 180,
  "mode": "normal",
  "model": "claude-opus-4-5-20251101",
  "prompts_changed_at": 1706472000.0,
  "completions_changed_at": 1706471980.0,
  "tool_timestamps": [1706471900.0, 1706471920.0, ...],
  "session_start": 1706471800.0,
  "idle_since": 1706472100.0
}

Stats UI (widget in session card):
- Single line: "5 prompts | 3 completions | 12 tools | 1 compression"
- Timing line: "45s thinking | 3m idle"
- Mode badge: "PLAN MODE" or "AUTO-ACCEPT" if not normal
- Model name: "opus-4-5" (shortened)
- Sparkline for tool activity using tool_timestamps (optional phase 2.5)

Stats storage:
- Add columns to sessions table: prompts, completions, tools, compressions,
  thinking_seconds, work_seconds, mode, model, idle_since
- Update on stats event (high frequency, throttle to every 5s)
- Show in dashboard session list (for quick scanning)


Git Status Extraction
----------------------

Git status widget shows current branch and file changes. Crabigator extracts this
by parsing git status output in the PTY stream. For clarc, two approaches:

Approach A (simple): Git hook in Claude Code
- Claude Code has git hooks that emit structured git events
- Listen for git events, store in session state
- Display in widget

Approach B (parse output): Pattern matching
- Watch PTY output for git commands (git status, git diff)
- Parse output to extract branch and file list
- Fragile but works without hook support

Recommendation: Approach A if hooks available, Approach B as fallback

Git event structure (from crabigator events.rs lines 95-121):
{
  "type": "git",
  "branch": "main",
  "files": [
    { "path": "src/index.ts", "status": "M ", "additions": 5, "deletions": 2 },
    { "path": "README.md", "status": "??", "additions": 0, "deletions": 0 }
  ]
}

Git widget UI:
- Collapsible card below stats, above output
- Header: branch name with git icon
- File list: path + status indicator (M/A/D/??) + diff count
- Color code: M=yellow, A=green, D=red, ??=gray
- Max 10 files shown, "and N more" if truncated
- No git data: hide widget entirely


SESSION STATE BADGES
====================

Claude Code sessions have explicit states (see crabigator events.rs lines 13-20):
- ready: idle, waiting for user input
- thinking: LLM processing request
- permission: waiting for tool permission
- question: waiting for question answer
- complete: session finished
- interrupted: user cancelled

Current: implicit state inference from prompt presence
Needed: explicit state tracking and visual badges

State event:
{
  "type": "state",
  "state": "thinking",
  "timestamp": 1706472000000
}

State badge UI (in session card header):
- ready: gray "READY"
- thinking: blue "THINKING" with animated dots
- permission: yellow "PERMISSION REQUIRED"
- question: yellow "QUESTION"
- complete: green "COMPLETE"
- interrupted: red "INTERRUPTED"

Badge behavior:
- Replace connection status indicator
- Connection status moves to header icon (filled=connected, outline=disconnected)
- State badge is primary status indicator
- Animate state transitions (fade between states)


UI ENHANCEMENTS
===============

Style Controls
--------------

Crabigator has comprehensive style popover (see dashboard.ts lines 69-132).
Priority features for phase 2:

High priority:
- Column layout: 1 / 2 / 3 / Fit (auto-columns based on viewport width)
- Text size: +/- buttons to scale font size (90% to 140% in 10% steps)
- Terminal height: +/- buttons to adjust output area (250px to 550px in 50px steps)
- Text wrap: toggle between wrap and horizontal scroll

Medium priority:
- Widget collapse: toggle for collapsing stats/git widgets
- Grouping: all sessions vs. by project (group by cwd)

Implementation:
- Store preferences in localStorage (key: clarc-prefs)
- Apply via CSS classes on container element
- Layout: data-layout="1" | "2" | "3" | "fit"
- Font size: CSS variable --font-scale
- Terminal height: CSS variable --terminal-height
- Wrap: class="terminal-wrap" vs. "terminal-scroll"


Session Filtering
-----------------

Focus mode: view single session, hide others. Useful for multi-session workspaces.

UI:
- Session count button in header (e.g., "3 sessions")
- Click to open popover with session list
- Each session: command + cwd + state badge
- Click session to filter to that session only
- Filter indicator shows in header: "Viewing 1 session" with X to clear
- Clear filter button returns to all sessions

Implementation:
- Store filter in component state (not localStorage - session-specific)
- Filter by session ID in render loop
- Popover positioned below sessions button


Auto-scroll Control
-------------------

Output auto-scrolls to bottom on new content. User scrolling up should pause
auto-scroll, with button to re-enable.

UI:
- Pin/unpin button in output footer
- Unpinned (auto-scroll on): pin icon, tooltip "Pin scroll position"
- Pinned (auto-scroll off): unpin icon, tooltip "Follow output"
- Auto-unpin when user scrolls up
- Auto-pin when user scrolls to bottom

Implementation:
- Track scroll position in output container
- On scroll event: if scrollTop + clientHeight < scrollHeight - 50, unpin
- On new content: if unpinned, scroll to bottom
- Pin button click: toggle unpinned state + scroll to bottom


DATA MODEL CHANGES
==================

Sessions Table Schema
---------------------

Current columns:
- id (primary key)
- command
- cwd
- started_at
- ended_at
- is_active

New columns for phase 2:

Stats:
- prompts INTEGER DEFAULT 0
- completions INTEGER DEFAULT 0
- tools INTEGER DEFAULT 0
- compressions INTEGER DEFAULT 0
- thinking_seconds INTEGER DEFAULT 0
- work_seconds INTEGER DEFAULT 0
- mode TEXT DEFAULT 'normal'
- model TEXT
- idle_since INTEGER  -- unix timestamp

State:
- state TEXT DEFAULT 'ready'  -- ready|thinking|permission|question|complete|interrupted

Git:
- git_branch TEXT
- git_files_json TEXT  -- JSON array of file objects

Prompt:
- current_prompt_json TEXT  -- serialized CloudPromptData or null

Migration:
- Add columns with ALTER TABLE
- Default values for existing rows
- No data loss for old sessions


Stats Storage Approach
----------------------

Stats events arrive frequently (every time a tool runs, every state change).
Two storage strategies:

Strategy A: Update on every event
- Simple: just UPDATE sessions SET ... WHERE id = ?
- High write volume, may cause SQLite lock contention

Strategy B: Throttle updates
- Update in-memory session state immediately (for SSE streaming)
- Persist to SQLite every 5 seconds if changed
- Trade-off: 5s data loss window on server crash
- Much lower write volume

Recommendation: Strategy B (throttled updates) for phase 2

Implementation:
- Session manager holds in-memory state map: Map<sessionId, SessionState>
- On stats event: update in-memory state, mark dirty
- Background interval (5s): persist all dirty sessions
- On session end: persist immediately


IMPLEMENTATION PHASES
=====================

Break implementation into atomic deliverables. Each phase should be independently
testable and useful.

Phase 2.1: Rich Prompt Foundation
----------------------------------

Goal: Support multi-option prompts without tab instructions yet

Tasks:
1. Define prompt types and response types (TypeScript interfaces)
2. Update session state to track current_prompt_json
3. Extend PTY wrapper to emit structured prompt events
4. Change /approve endpoint to /answer endpoint with response types
5. Render permission prompts with option list (no tab instructions yet)
6. Render question prompts with option list (no "Other" yet)
7. Test: permission prompt with 3 options (yes/yes always/no)

Deliverable: Can approve tool permissions by selecting specific option

Phase 2.2: Text Input and Tab Instructions
-------------------------------------------

Goal: Complete prompt system with all input types

Tasks:
1. Add "Other" text input for question prompts
2. Add "Add instructions" button for permission prompts
3. Implement key sequence generation for tab instructions
4. Implement key sequence execution in PTY wrapper
5. Test: question prompt with "Other" option
6. Test: permission prompt with tab instructions

Deliverable: Full prompt interactivity matches desktop Claude Code

Phase 2.3: Session States and Stats
------------------------------------

Goal: Track and display session state and statistics

Tasks:
1. Add state/stats columns to sessions table (migration)
2. Parse and emit state events from PTY output
3. Parse and emit stats events from PTY output
4. Update session state in database (throttled writes)
5. Add state badges to session card headers
6. Add stats widget to session cards
7. Test: state transitions visible in UI
8. Test: stats update as session progresses

Deliverable: Rich session metadata visible in dashboard

Phase 2.4: ANSI Colors
----------------------

Goal: Colored terminal output

Tasks:
1. Add ansi-to-html dependency
2. Parse ANSI codes in output before SSE transmission
3. Add terminal color CSS classes
4. Update output rendering to preserve HTML spans
5. Test: colored tool output (git diff, test results)

Deliverable: Output looks like terminal, not plain text

Phase 2.5: Git Widget
---------------------

Goal: Show git status for sessions in git repositories

Tasks:
1. Add git columns to sessions table (migration)
2. Parse git events from PTY output (pattern matching or hooks)
3. Add git widget component to session cards
4. Update widget on git events
5. Test: git status visible after git commands

Deliverable: Git branch and file changes visible in dashboard

Phase 2.6: UI Polish
--------------------

Goal: Style controls and UX improvements

Tasks:
1. Add style popover with column layout options
2. Add text size +/- controls
3. Add terminal height +/- controls
4. Add text wrap toggle
5. Add session filtering (focus mode)
6. Add auto-scroll control (pin/unpin)
7. Persist preferences to localStorage
8. Test: style changes apply correctly
9. Test: filter to single session works

Deliverable: Dashboard matches crabigator's UX quality


TESTING STRATEGY
================

Each phase needs:
- Unit tests for new functions (prompt parsing, key sequence generation)
- Integration tests for API endpoints (answer endpoint with different response types)
- Manual testing with real Claude Code sessions

Key test scenarios:
- Permission prompt: approve with each option (yes / yes always / no)
- Permission prompt: add tab instructions
- Question prompt: select numbered option
- Question prompt: enter "Other" text
- State transitions: ready -> thinking -> permission -> ready
- Stats updates: watch counts increment during session
- Git status: run git commands, verify widget updates
- ANSI colors: run command with colored output (git status, test runner)
- Style controls: change layout, font size, terminal height
- Session filter: filter to one session, clear filter
- Auto-scroll: scroll up to pause, scroll down to resume


OPEN QUESTIONS
==============

1. Hook availability: Does Claude Code expose hooks for git/stats/prompts?
   - If yes: use structured events
   - If no: parse PTY output (fragile but workable)

2. Key sequence timing: What delays needed between key presses?
   - Start with 100ms, adjust based on testing
   - May need longer delays for slow terminal responses

3. Prompt detection: How to reliably detect prompt boundaries in output?
   - Look for specific patterns in PTY output
   - May need escape sequence markers
   - Fallback: timeout-based detection (no output for 500ms = prompt)

4. Stats persistence frequency: 5s throttle good enough?
   - Depends on write volume and SQLite performance
   - Monitor DB file size growth
   - May need adaptive throttling (1s when active, 10s when idle)


REFERENCES
==========

Crabigator patterns to steal from:
- workers/crabigator-api/src/durable-objects/SessionDO.ts (lines 330-419)
  State management, event handling, persistence strategy
- src/cloud/events.rs (lines 1-741)
  Event type definitions, prompt structures, key sequences
- workers/crabigator-api/src/dashboard.ts (lines 69-132)
  Style controls UI patterns

Claude Code documentation:
- Prompt hooks: check official docs for hook event structures
- PTY escape codes: standard ANSI/VT100 sequences