# CLAUDE.md

This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.

## Project Overview

Dereth Tracker is a real-time telemetry service for game world tracking. It's a FastAPI-based WebSocket and HTTP API service that ingests player position/stats data via plugins and provides live map visualization through a web interface.

## Key Components

### Main Service (main.py)
- WebSocket endpoint `/ws/position` receives telemetry and inventory events
- Routes inventory events to inventory service via HTTP
- Handles real-time player tracking and map updates

### Inventory Service (inventory-service/main.py)
- Separate FastAPI service for inventory management
- Processes inventory JSON into normalized PostgreSQL tables
- Provides search API with advanced filtering and sorting
- Uses comprehensive enum database for translating game IDs to readable names

### Database Architecture
- **Telemetry DB**: TimescaleDB for time-series player tracking data
- **Inventory DB**: PostgreSQL with normalized schema for equipment data
  - `items`: Core item properties
  - `item_combat_stats`: Armor level, damage bonuses
  - `item_enhancements`: Material, item sets, tinkering
  - `item_spells`: Spell names and categories
  - `item_raw_data`: Original JSON for complex queries

## Memories and Known Bugs

* Fixed: Material names now properly display (e.g., "Gold Celdon Girth" instead of "Unknown_Material_Gold Celdon Girth")
* Fixed: Slot column shows "-" instead of "Unknown" for items without slot data
* Fixed: All 208 items in Larsson's inventory now process successfully (was 186 with 22 SQL type errors)
* Added: Type column in inventory search using object_classes enum for accurate item type classification
* Note: ItemType data is inconsistent in JSON - using ObjectClass as primary source for Type column

## Recent Fixes (September 2025)

### Portal Coordinate Rounding Fix ✅ RESOLVED
* **Problem**: Portal insertion failed with duplicate key errors due to coordinate rounding mismatch
* **Root Cause**: Code used 2 decimal places (`ROUND(ns::numeric, 2)`) but database constraint used 1 decimal place
* **Solution**: Changed all portal coordinate checks to use 1 decimal place to match DB constraint
* **Result**: 98% reduction in duplicate key errors (from 600+/min to ~11/min)
* **Location**: `main.py` lines ~1989, 1996, 2025, 2047

### Character Display Issues ✅ RESOLVED
* **Problem**: Some characters (e.g., "Crazed n Dazed") not appearing in frontend
* **Root Cause**: Database connection pool exhaustion from portal error spam
* **Solution**: Fixed portal errors to reduce database load
* **Result**: Characters now display correctly after portal fix

### Docker Container Deployment
* **Issue**: Code changes require container rebuild with `--no-cache` flag
* **Command**: `docker compose build --no-cache dereth-tracker`
* **Reason**: Docker layer caching can prevent updated source code from being copied

## Current Known Issues

### Minor Portal Race Conditions
* **Status**: ~11 duplicate key errors per minute (down from 600+)
* **Cause**: Multiple players discovering same portal simultaneously
* **Impact**: Minimal - errors are caught and handled gracefully
* **Handling**: Try/catch in code logs as debug messages and updates portal timestamp
* **Potential Fix**: PostgreSQL ON CONFLICT DO UPDATE (upsert pattern) would eliminate completely

### Database Initialization Warnings
* **TimescaleDB Hypertable**: `telemetry_events` fails to become hypertable due to primary key constraint
* **Impact**: None - table works as regular PostgreSQL table
* **Warning**: "cannot create a unique index without the column 'timestamp'"

### Connection Pool Under Load
* **Issue**: Database queries can timeout when connection pool is exhausted
* **Symptom**: Characters may not appear during high error load
* **Mitigation**: Portal error fix significantly reduced this issue

## Equipment Suit Builder

### Status: PRODUCTION READY

Real-time equipment optimization engine for building optimal character loadouts by searching across multiple characters' inventories (mules). Uses Mag-SuitBuilder constraint satisfaction algorithms.

**Core Features:**
- Multi-character inventory search across 100+ characters, 25,000+ items
- Armor set constraints (primary 5-piece + secondary 4-piece set support)
- Cantrip/ward spell optimization with bitmap-based overlap detection
- Crit damage rating optimization
- Locked slots with set/spell preservation across searches
- Real-time SSE streaming with progressive phase updates
- Suit summary with copy-to-clipboard functionality
- Stable deterministic sorting for reproducible results

**Access:** `/suitbuilder.html`

**Architecture Details:** See `docs/plans/2026-02-09-suitbuilder-architecture.md`

### Known Limitations
- Slot-aware spell filtering not yet implemented (e.g., underclothes have limited spell pools but system treats all slots equally)
- All spells weighted equally (no priority/importance weighting yet)
- See architecture doc for future enhancement roadmap

## Technical Notes for Development

### Database Performance
- Connection pool: 5-20 connections (configured in `db_async.py`)
- Under heavy error load, pool exhaustion can cause 2-minute query timeouts
- Portal error fix significantly improved database performance

### Docker Development Workflow
1. **Code Changes**: Edit source files locally
2. **Rebuild**: `docker compose build --no-cache dereth-tracker` (required for code changes)
3. **Deploy**: `docker compose up -d dereth-tracker`
4. **Debug**: `docker logs mosswartoverlord-dereth-tracker-1` and `docker logs dereth-db`

### Frontend Architecture
- **Main Map**: `static/index.html` - Real-time player tracking
- **Inventory Search**: `static/inventory.html` - Advanced item filtering
- **Suitbuilder**: `static/suitbuilder.html` - Equipment optimization interface
- **All static files**: Served directly by FastAPI StaticFiles

### DOM Optimization Status ✅ COMPLETE (September 2025)
* **Achievement**: 100% DOM element reuse with zero element creation after initial render
* **Performance**: ~5ms render time for 69 players, eliminated 4,140+ elements/minute creation
* **Implementation**: Element pooling system with player name mapping for O(1) lookup
* **Monitoring**: Color-coded console output (✨ green = optimized, ⚡ yellow = partial, 🔥 red = poor)
* **Status**: Production ready - achieving perfect element reuse consistently

**Current Render Stats**:
- ✅ This render: 0 dots created, 69 reused | 0 list items created, 69 reused
- ✅ Lifetime: 69 dots created, 800+ reused | 69 list items created, 800+ reused

**Remaining TODO**:
- ❌ Fix CSS Grid layout for player sidebar (deferred per user request)
- ❌ Extend optimization to trails and portal rendering
- ❌ Add memory usage tracking

### WebSocket Endpoints
- `/ws/position`: Plugin telemetry, inventory, portal, rare events (authenticated)
- `/ws/live`: Browser client commands and live updates (unauthenticated)