---
phase: 09-message-composition
plan: 01
subsystem: ui
tags: [react, redux, chat, forms, validation, keyboard-handling]

# Dependency graph
requires:
  - phase: 07-chat-infrastructure
    provides: sendMessage thunk, Redux selectors
  - phase: 08-chat-window-ui
    provides: Chat window shell, message list display
provides:
  - Message composition UI with textarea
  - Character count validation (1-255 chars)
  - Keyboard handling (Enter/Shift+Enter)
  - Visual feedback for validation states
affects: [09-message-composition, 10-read-unread-status, 11-chat-finalization]

# Tech tracking
tech-stack:
  added: []
  patterns: [controlled-components, local-state-for-ephemeral-ui, character-validation]

key-files:
  created: [jam-ui/src/components/client/chat/JKChatComposer.js]
  modified: []

key-decisions:
  - "Local state for inputText (ephemeral, no Redux needed)"
  - "Trim whitespace before validation (1-255 chars after trim)"
  - "Three-tier character count feedback: gray (0-230), yellow (231-255), red (256+)"
  - "Enter sends, Shift+Enter for newline (standard chat UX pattern)"

patterns-established:
  - "Character count with overflow prevention (X/255 format)"
  - "Validation messages guide user input (over-limit, empty, disconnected)"
  - "Disabled states: !isConnected, isSending, !isValid"

issues-created: []

# Metrics
duration: 4min
completed: 2026-01-27
---

# Phase 9 Plan 1: Message Composer UI & Validation Summary

**Created message composer with textarea, keyboard handling (Enter/Shift+Enter), character validation (1-255), and visual feedback**

## Performance

- **Duration:** 4 min
- **Started:** 2026-01-27T09:47:00Z
- **Completed:** 2026-01-27T09:51:33Z
- **Tasks:** 3
- **Files modified:** 1

## Accomplishments

- JKChatComposer component with controlled textarea
- Character count display (X/255) with color-coded feedback (gray/yellow/red)
- Validation: empty check after trim, 255-char limit
- Keyboard handling: Enter to send, Shift+Enter for newline
- Disabled states: disconnected, sending, invalid input
- Error display for send failures and disconnected warning
- React.memo and useCallback optimizations

## Task Commits

1. **Tasks 1-3: Create JKChatComposer** - `d4fc7005d` (feat)
   - All three tasks modified the same component file
   - Combined into single commit for atomic delivery

**Plan metadata:** (pending - will commit with SUMMARY)

## Files Created/Modified

**Created:**
- `jam-ui/src/components/client/chat/JKChatComposer.js` - Message composition component with validation

## Decisions Made

**Local state for inputText:**
- Input text is ephemeral UI state (doesn't need Redux persistence)
- Cleared after successful send
- No sharing needed with other components

**Validation approach:**
- Trim whitespace before checking length (prevents whitespace-only messages)
- 1-255 character range after trim
- Three-tier feedback: gray (normal), yellow (approaching limit at 231+), red (over limit)

**Keyboard UX:**
- Enter key: send message (if valid)
- Shift+Enter: insert newline (multi-line messages)
- preventDefault on Enter to avoid newline + send

**Disabled logic:**
- Textarea disabled when: !isConnected OR isSending
- Send button disabled when: !isConnected OR isSending OR !isValid

## Deviations from Plan

None - plan executed exactly as written.

## Issues Encountered

None

## Next Phase Readiness

- Composer component ready for integration into chat window (Plan 09-02)
- sendMessage thunk already exists in Redux (Phase 7)
- Component exports properly with React.memo optimization
- No PropTypes warnings or console errors

---
*Phase: 09-message-composition*
*Completed: 2026-01-27*
