strat-gameplay-webapp/backend
Cal Corum e147ab17f1 CLAUDE: Phase 3F - Substitution System WebSocket Events
Implemented complete WebSocket integration for real-time player substitutions.
System is now 80% complete - only tests remain.

## WebSocket Events Implemented (600 lines)

### Event Handlers (backend/app/websocket/handlers.py):
1. request_pinch_hitter - Pinch hitter substitution
   - Validates: game_id, player_out_lineup_id, player_in_card_id, team_id
   - Executes: SubstitutionManager.pinch_hit()
   - Broadcasts: player_substituted (all clients), substitution_confirmed (requester)
   - Error codes: MISSING_FIELD, INVALID_FORMAT, NOT_CURRENT_BATTER, etc.

2. request_defensive_replacement - Defensive replacement
   - Additional field: new_position (P, C, 1B, 2B, 3B, SS, LF, CF, RF)
   - Executes: SubstitutionManager.defensive_replace()
   - Same broadcast pattern as pinch hitter

3. request_pitching_change - Pitching change
   - Validates minimum batters faced (handled in SubstitutionManager)
   - Executes: SubstitutionManager.change_pitcher()
   - Broadcasts new pitcher to all clients

4. get_lineup - Get active lineup for team
   - Returns: lineup_data with all active players
   - Uses: StateManager cache (O(1)) or database fallback
   - Purpose: UI refresh after substitutions

### Event Pattern (follows existing handlers):
- Validate inputs (UUID format, required fields, game exists)
- Create SubstitutionManager instance with DatabaseOperations
- Execute substitution (validate → DB → state)
- Broadcast player_substituted to game room
- Send substitution_confirmed to requester
- Error handling with specific error codes

### Events Emitted:
- player_substituted (broadcast) - Includes: type, lineup IDs, position, batting_order
- substitution_confirmed (requester) - Success confirmation with new_lineup_id
- substitution_error (requester) - Validation error with error code
- lineup_data (requester) - Active lineup response
- error (requester) - Generic error

## Documentation Updates (350 lines)

### backend/app/websocket/CLAUDE.md:
- Complete handler documentation with examples
- Event data structures and response formats
- Error code reference (MISSING_FIELD, INVALID_FORMAT, NOT_CURRENT_BATTER, etc.)
- Client integration examples (JavaScript)
- Complete workflow diagrams
- Updated event summary table (+8 events)
- Updated Common Imports section

### .claude/implementation/ updates:
- NEXT_SESSION.md: Marked Task 1 complete, updated to 80% done
- SUBSTITUTION_SYSTEM_SUMMARY.md: Added WebSocket section, updated status
- GAMESTATE_REFACTOR_PLAN.md: Marked complete
- PHASE_3_OVERVIEW.md: Updated all phases to reflect completion
- phase-3e-COMPLETED.md: Created comprehensive completion doc

## Architecture

### DB-First Pattern (maintained):
```
Client Request → WebSocket Handler
    ↓
SubstitutionManager
    ├─ SubstitutionRules.validate_*()
    ├─ DatabaseOperations.create_substitution() (DB first!)
    ├─ StateManager.update_lineup_cache()
    └─ Update GameState if applicable
    ↓
Success Responses
    ├─ player_substituted (broadcast to room)
    └─ substitution_confirmed (to requester)
```

### Error Handling:
- Three-tier: ValidationError, GameValidationError, Exception
- Specific error codes for each failure type
- User-friendly error messages
- Comprehensive logging at each step

## Status Update

**Phase 3F Substitution System**: 80% Complete
-  Core logic (SubstitutionRules, SubstitutionManager) - 1,027 lines
-  Database operations (create_substitution, get_eligible_substitutes)
-  WebSocket events (4 handlers) - 600 lines
-  Documentation (350 lines)
-  Unit tests (20% remaining) - ~300 lines needed
-  Integration tests - ~400 lines needed

**Phase 3 Overall**: ~97% Complete
- Phase 3A-D (X-Check Core): 100%
- Phase 3E (GameState, Ratings, Redis, Testing): 100%
- Phase 3F (Substitutions): 80%

## Files Modified

backend/app/websocket/handlers.py (+600 lines)
backend/app/websocket/CLAUDE.md (+350 lines)
.claude/implementation/NEXT_SESSION.md (updated progress)
.claude/implementation/SUBSTITUTION_SYSTEM_SUMMARY.md (added WebSocket section)
.claude/implementation/GAMESTATE_REFACTOR_PLAN.md (marked complete)
.claude/implementation/PHASE_3_OVERVIEW.md (updated all phases)
.claude/implementation/phase-3e-COMPLETED.md (new file, 400+ lines)

## Next Steps

Remaining work (2-3 hours):
1. Unit tests for SubstitutionRules (~300 lines)
   - 15+ pinch hitter tests
   - 12+ defensive replacement tests
   - 10+ pitching change tests
2. Integration tests for SubstitutionManager (~400 lines)
   - Full DB + state sync flow
   - State recovery verification
   - Error handling and rollback

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>
2025-11-04 21:24:43 -06:00
..
.claude CLAUDE: Refactor GameEngine to forward-looking play tracking pattern 2025-10-25 22:18:15 -05:00
.git-hooks CLAUDE: Fix all unit test failures and implement 100% test requirement 2025-11-04 19:35:21 -06:00
app CLAUDE: Phase 3F - Substitution System WebSocket Events 2025-11-04 21:24:43 -06:00
scripts CLAUDE: Refactor GameEngine to forward-looking play tracking pattern 2025-10-25 22:18:15 -05:00
terminal_client CLAUDE: Fix all unit test failures and implement 100% test requirement 2025-11-04 19:35:21 -06:00
tests CLAUDE: Fix all unit test failures and implement 100% test requirement 2025-11-04 19:35:21 -06:00
.dockerignore CLAUDE: Fix Docker build for UV migration 2025-11-04 09:19:30 -06:00
.env.example CLAUDE: Complete Phase 1 backend infrastructure setup 2025-10-21 19:46:16 -05:00
.python-version CLAUDE: Migrate backend to UV package management 2025-11-04 08:52:11 -06:00
CLAUDE.md CLAUDE: Fix all unit test failures and implement 100% test requirement 2025-11-04 19:35:21 -06:00
clean_test_data.py CLAUDE: Refactor game models and modularize terminal client 2025-10-28 14:16:38 -05:00
docker-compose.yml CLAUDE: Complete Phase 1 backend infrastructure setup 2025-10-21 19:46:16 -05:00
Dockerfile CLAUDE: Fix Docker build for UV migration 2025-11-04 09:19:30 -06:00
mypy.ini CLAUDE: Refactor GameEngine to forward-looking play tracking pattern 2025-10-25 22:18:15 -05:00
pyproject.toml CLAUDE: Update REPL for new GameState and standardize UV commands 2025-11-04 09:59:13 -06:00
pyrightconfig.json Clean up false positive Pylance errors 2025-10-23 09:10:41 -05:00
pytest.ini CLAUDE: Complete Week 4 - State Management & Persistence 2025-10-22 12:01:03 -05:00
README.md CLAUDE: Fix Docker build for UV migration 2025-11-04 09:19:30 -06:00
requirements-dev.txt CLAUDE: Complete Phase 1 backend infrastructure setup 2025-10-21 19:46:16 -05:00
requirements.txt CLAUDE: Add interactive terminal client for game engine testing 2025-10-26 12:51:01 -05:00
test_db_playground.py Add scripts to test models in dev database 2025-10-23 09:10:55 -05:00
test_pd_api_live.py CLAUDE: Phase 3E-Main - Position Ratings Integration for X-Check Resolution 2025-11-03 21:00:37 -06:00
test_pd_api_mock.py CLAUDE: Phase 3E-Main - Position Ratings Integration for X-Check Resolution 2025-11-03 21:00:37 -06:00
test_redis_cache.py CLAUDE: Phase 3E-Final - Redis Caching & X-Check WebSocket Integration 2025-11-03 22:46:59 -06:00
uv.lock CLAUDE: Fix game recovery for new GameState structure 2025-11-04 15:26:00 -06:00

Paper Dynasty Backend

FastAPI-based real-time baseball game engine with WebSocket support.

Quick Start

# Install UV
curl -LsSf https://astral.sh/uv/install.sh | sh

# Install dependencies
uv sync

# Run server
uv run python -m app.main

Documentation

See CLAUDE.md for full documentation.