backend/main.py

"""
GCP - Game Context Protocol Server
FastAPI server for the 3D scene viewer HTTP endpoints.
MCP tools are defined in mcp_server.py
"""
import os
from pathlib import Path
from fastapi import FastAPI, HTTPException
from fastapi.responses import HTMLResponse, JSONResponse
from fastapi.middleware.cors import CORSMiddleware
from fastapi.staticfiles import StaticFiles

from backend.storage import storage

# Get project root directory
PROJECT_ROOT = Path(__file__).parent.parent

# Create FastAPI app
app = FastAPI(
    title="GCP - Game Context Protocol",
    description="3D scene building server. Use MCP tools via Claude/AI assistants, or view scenes via HTTP.",
    version="2.0.0",
)

# Add CORS middleware
app.add_middleware(
    CORSMiddleware,
    allow_origins=["*"],
    allow_credentials=True,
    allow_methods=["*"],
    allow_headers=["*"],
)

# Mount static files for models
models_path = PROJECT_ROOT / "models"
if models_path.exists():
    app.mount("/static/models", StaticFiles(directory=str(models_path)), name="models")


# =============================================================================
# HTTP Endpoints (for viewer and health checks)
# =============================================================================

@app.get("/health")
async def health_check():
    """Health check endpoint for startup verification."""
    return {
        "status": "healthy",
        "service": "GCP - Game Context Protocol",
        "version": "2.0.0",
    }


@app.get("/api")
async def api_root():
    """API root endpoint with API information."""
    return {
        "name": "GCP - Game Context Protocol",
        "version": "2.0.0",
        "description": "MCP server for building 3D scenes with AI assistants",
        "endpoints": {
            "viewer": "/view/scene/{scene_id}",
            "scene_data": "/api/scenes/{scene_id}",
            "health": "/health",
        },
        "mcp": "Connect via stdio transport using: python -m backend.mcp_server",
    }


@app.get("/api/scenes/{scene_id}")
async def get_scene_api(scene_id: str):
    """Get scene configuration and data as JSON."""
    scene = storage.get(scene_id)
    if not scene:
        raise HTTPException(status_code=404, detail=f"Scene '{scene_id}' not found")
    return scene


@app.get("/view/scene/{scene_id}")
async def view_scene(scene_id: str):
    """Serve the Three.js viewer for a scene."""
    scene = storage.get(scene_id)
    if not scene:
        raise HTTPException(status_code=404, detail=f"Scene '{scene_id}' not found")

    # Serve the game viewer HTML
    try:
        viewer_path = os.path.join(os.path.dirname(__file__), "..", "frontend", "game_viewer.html")
        with open(viewer_path, 'r') as f:
            html_content = f.read()
        return HTMLResponse(content=html_content)
    except FileNotFoundError:
        raise HTTPException(status_code=500, detail="Game viewer HTML not found")


@app.get("/manifest.json")
async def get_manifest():
    """Serve PWA manifest to avoid 404 errors."""
    try:
        manifest_path = os.path.join(os.path.dirname(__file__), "..", "frontend", "manifest.json")
        with open(manifest_path, 'r') as f:
            import json
            manifest_content = json.load(f)
        return JSONResponse(content=manifest_content)
    except FileNotFoundError:
        return JSONResponse(content={"name": "GCP", "short_name": "GCP"})


# =============================================================================
# Run server
# =============================================================================

if __name__ == "__main__":
    import uvicorn
    uvicorn.run(app, host="0.0.0.0", port=8000)