Catacombs/CLAUDE.md

CLAUDE.md

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

Project Overview

Catacombs is a multiplayer roguelike dungeon crawler with dual access: SSH (native TUI) and HTTP/WebSocket (web browser via xterm.js). Written in Go, it uses Bubble Tea for the terminal UI and BoltDB for persistence.

Build & Run Commands

go build -o catacombs .          # Build
go test ./...                     # Run all tests
go test ./combat/                 # Run tests for a single package
go test ./entity/ -run TestName   # Run a specific test
go vet ./...                      # Lint

Docker:

docker build -t catacombs .
docker-compose up                 # SSH on :2222, HTTP on :8080

Architecture

Package dependency flow: main → server/web/store → game → dungeon → entity → combat

Package	Responsibility
main.go	Entry point: initializes BoltDB (./data/catacombs.db), starts SSH server (:2222) and HTTP server (:8080)
game/	Lobby (room management, player tracking, reconnection), GameSession (turn-based state), turn execution (5s action timeout), room events (combat/shop/treasure)
ui/	Bubble Tea state machine with 8 screen states (nickname → lobby → class select → game → shop → result → leaderboard → achievements). model.go is the central state machine (~19K lines)
dungeon/	BSP tree procedural generation (60x20 maps), ASCII rendering with floor themes, field-of-view
entity/	Player (4 classes: Warrior/Mage/Healer/Rogue), Monster (8 types + 4 bosses with floor scaling), Items/Relics
combat/	Damage calculation, monster AI targeting, cooperative damage bonus
store/	BoltDB persistence: profiles, rankings, achievements (10 unlockable)
server/	Wish SSH server with fingerprint-based auth
web/	HTTP + WebSocket bridge to SSH, embedded xterm.js frontend

Key Patterns

• Concurrent session management: Mutex-protected game state for multi-player synchronization (up to 4 players per room)
• Turn-based action collection: 5-second timeout window; players who don't submit default to "Wait"
• SSH fingerprint reconnection: Players reconnect to active sessions via Lobby.activeSessions fingerprint mapping
• Dual access: SSH server (native PTY) and HTTP/WebSocket (xterm.js) share the same Lobby and DB instances
• Combat log reveal: Logs shown incrementally via PendingLogs → CombatLog system

Game Balance Constants

• 20 floors with bosses at 5, 10, 15, 20
• Monster scaling: 1.15x power per floor above minimum
• Solo mode halves enemy stats
• Cooperative bonus: +10% damage when 2+ players target same enemy
• Inventory limit: 10 items, 3 skill uses per combat