chess_game/web_app.py

import os
import uuid

from fastapi import FastAPI, Request, HTTPException
from fastapi.responses import HTMLResponse, JSONResponse, RedirectResponse
from fastapi.staticfiles import StaticFiles
from fastapi.templating import Jinja2Templates

from .chess_server import start_game as m_start_game, player_move as m_player_move, ai_move as m_ai_move, board as m_board, legal_moves as m_legal_moves, status as m_status, pgn as m_pgn


BASE_DIR = os.path.dirname(__file__)
TEMPLATES_DIR = os.path.join(BASE_DIR, "templates")
STATIC_DIR = os.path.join(BASE_DIR, "static")


app = FastAPI()
app.mount("/static", StaticFiles(directory=STATIC_DIR), name="static")
templates = Jinja2Templates(directory=TEMPLATES_DIR)


# Simple room registry for UI convenience (MCP state keyed by room_id in chess_server)
rooms = {}


def generate_room_id() -> str:
    return uuid.uuid4().hex[:8]


@app.get("/", response_class=HTMLResponse)
def home(request: Request):
    base_path = request.scope.get('root_path', '')
    return templates.TemplateResponse("index.html", {"request": request, "rooms": rooms, "base_path": base_path})


@app.post("/create_room")
def create_room(request: Request):
    # Choose a new room id and redirect to room page; player picks color there
    room_id = generate_room_id()
    rooms[room_id] = {"id": room_id}
    return RedirectResponse(url=f"{request.scope.get('root_path', '')}/room/{room_id}", status_code=303)


@app.get("/room/{room_id}", response_class=HTMLResponse)
def room_page(room_id: str, request: Request):
    base_path = request.scope.get('root_path', '')
    # Fetch board (this also ensures MCP game exists lazily)
    state = m_board(session_id=room_id)
    if room_id not in rooms:
        rooms[room_id] = {"id": room_id}
    return templates.TemplateResponse("room.html", {"request": request, "room_id": room_id, "state": state, "base_path": base_path})


# --- API: Map to MCP tools ---


@app.post("/room/{room_id}/start")
def api_start(room_id: str, payload: dict | None = None):
    player_color = (payload or {}).get("player_color", "white")
    state = m_start_game(session_id=room_id, player_color=player_color)
    return JSONResponse(state)


@app.post("/room/{room_id}/player_move")
def api_player_move(room_id: str, payload: dict):
    if not payload or "move" not in payload:
        raise HTTPException(status_code=400, detail="Missing 'move' in body")
    result = m_player_move(move=payload["move"], session_id=room_id)
    if "error" in result:
        raise HTTPException(status_code=400, detail=result["error"])
    return JSONResponse(result)


@app.post("/room/{room_id}/ai_move")
def api_ai_move(room_id: str):
    result = m_ai_move(session_id=room_id)
    return JSONResponse(result)


@app.get("/room/{room_id}/board")
def api_board(room_id: str):
    return JSONResponse(m_board(session_id=room_id))


@app.get("/room/{room_id}/legal_moves")
def api_legal_moves(room_id: str):
    return JSONResponse(m_legal_moves(session_id=room_id))


@app.get("/room/{room_id}/status")
def api_status(room_id: str):
    return JSONResponse(m_status(session_id=room_id))


@app.get("/room/{room_id}/pgn")
def api_pgn(room_id: str):
    return JSONResponse({"pgn": m_pgn(session_id=room_id)})