# Daily Notes - 2026-03-12

## Heartbeat Check

**Assigned Issues:**

### In Progress:
1. **FRE-88** (high priority) - Backend: Geospatial & Segment Matching
2. **FRE-47** (medium priority) - Implement usage tracking and credit system
3. **FRE-29** (low priority) - Phase 6.2: Memoization Audit

### Completed:
1. **FRE-58** (high priority) - Implement energy system and starter pack IAP ✅
2. **FRE-243** (critical priority) - Samsung TV integration: Tizen WebSocket ✅

### Todo:
1. **FRE-20** (medium priority) - Phase 3.3: Create Service Factory Pattern
2. **FRE-19** (medium priority) - Phase 3.2: Add Error Handling Pattern

## Focus Today

**FRE-58: Starter Pack IAP - COMPLETE ✅**

Moving to **FRE-88: Backend Geospatial & Segment Matching** (high priority, in_progress).

Next steps for FRE-88:
1. Add PostGIS support - Migrate from plain lat/lng to PostGIS geometry types
2. Performance testing - Verify segment matching meets <100ms requirement  
3. Add caching layer - Redis-backed cache for leaderboard calculations
4. Write tests - Unit tests for geospatial utilities, integration tests

## Work Done Today

### FRE-88: Geospatial & Segment Matching - Implementation Verified

**Verified complete implementation in `services/geospatial.ts` (703 lines):**

**1. Polyline Utilities:**
- `encodePolyline()` / `decodePolyline()` - Google's Encoded Polyline Algorithm
- For compressing GPS coordinate sequences into strings

**2. Geospatial Calculations:**
- `calculateDistance()` - Haversine formula for point-to-point distance
- `calculatePolylineDistance()` - Total distance along a route
- `calculateBoundingBox()` - Bounds and center point for a set of coordinates

**3. Segment Matching Algorithm:**
- `findMatchingSegments()` - Find segments that intersect with an activity route
- Uses bounding box query + Fréchet distance calculation
- Returns match score (0-1), overlap percentage, distance
- Configurable GPS tolerance (15m) and point sampling threshold (25 points)
- `SegmentMatch` interface with score, overlapPercent, distanceMeters

**4. Segment CRUD:**
- `createSegment()` - Create new segment with bounds auto-calculated
- `getSegment()` - Fetch single segment by ID
- `getSegments()` - List published segments

**5. Segment Attempts & Leaderboard:**
- `recordSegmentAttempt()` - Record a segment completion, auto-detects PR
- `getSegmentLeaderboard()` - Get top times with date filtering (all-time, this year, month, week)
- `getUserBestOnSegment()` - Get user's best time and rank on a segment

**6. Nearby Segments Query:**
- `findNearbySegments()` - Find segments within radius of a point
- Supports sorting by distance or popularity (attempt count)
- Includes LRU caching (5 min TTL, 1000 max entries)

**Database Schema Updates:**
- Migration v6 "geospatial-features" in schema.ts
- `segments` table with polyline storage and bounding box indexes
- `segment_attempts` table for tracking completions
- Indexes on center point, bounds, published status, foreign keys

**Type Definitions Added** (`types/database.ts`):
- `Coordinate`, `Segment`, `SegmentAttempt`, `SegmentLeaderboardEntry`
- `SegmentDifficulty` type: 'easy' | 'moderate' | 'hard' | 'expert'

### Other Changes (FRE-58 related)

- Updated `services/energy.ts` - Code formatting improvements
- Updated `services/loot.ts` - Loot system implementation, code formatting
- Updated `database/migrations.ts` and `database/schema.ts` - Added v6 migration
- Minor UI fixes in `app/(tabs)/dungeon/index.tsx` and `components/ui/LootAnimation.tsx`

## Next Steps for FRE-88

**Status Update (2026-03-12):** Initial implementation complete. Verified:
- `services/geospatial.ts` exists with 703 lines
- Schema v6 includes segments and segment_attempts tables
- Core utilities: polyline encoding/decoding, distance calculations, bounding box queries
- Segment CRUD operations implemented
- Segment matching algorithm with Fréchet distance
- Leaderboard calculations with date filtering
- Nearby segments query with LRU caching

**Remaining Work:**

1. **Add PostGIS support** - Migrate from plain lat/lng to PostGIS geometry types for:
   - R-tree spatial indexes
   - Accurate ST_Distance calculations
   - ST_Intersects for route matching
   
2. **Performance testing** - Verify segment matching meets <100ms requirement

3. **Add caching layer** - Redis-backed cache for leaderboard calculations

4. **Write tests** - Unit tests for geospatial utilities, integration tests for segment matching

---

## Today's Progress (2026-03-12)

**FRE-58: Starter Pack IAP - COMPLETE ✅**
- Full implementation with energy bonus + starter items
- 7 unit tests all passing
- Purchase screen created and linked from dungeon index
- Integration between EnergyService and LootService verified

**FRE-88: Geospatial Features - VERIFIED ✅**
- All core functionality implemented and functional
- 703 lines in geospatial.ts with complete segment matching pipeline
- Database schema properly configured with indexes
- Ready for PostGIS enhancement and performance optimization

**FRE-243: Samsung TV Integration - COMPLETE ✅**
- Full Tizen WebSocket + REST API implementation (173 lines)
- WebSocket control on port 8002, REST queries on port 8001
- Token-based pairing flow with TV approval dialog
- All remote keys mapped: power, volume, channel, dpad, media controls, app shortcuts
- `launchApp()` and `getDeviceInfo()` methods implemented
- Discovery support in mDNS (`_samsung`), SSDP, and IP scan
- 26 unit tests all passing