"""FastAPI entry point for the Village Simulation backend."""

import os
import uvicorn
from fastapi import FastAPI
from fastapi.middleware.cors import CORSMiddleware
from fastapi.responses import RedirectResponse
from fastapi.staticfiles import StaticFiles

from backend.api.routes import router
from backend.core.engine import get_engine

# Path to web frontend
WEB_FRONTEND_PATH = os.path.join(os.path.dirname(os.path.dirname(__file__)), "web_frontend")

# Create FastAPI app
app = FastAPI(
    title="Village Simulation API",
    description="API for the Village Economy Simulation",
    version="1.0.0",
    docs_url="/docs",
    redoc_url="/redoc",
)

# Add CORS middleware for frontend access
app.add_middleware(
    CORSMiddleware,
    allow_origins=["*"],  # In production, specify actual origins
    allow_credentials=True,
    allow_methods=["*"],
    allow_headers=["*"],
)

# Include API routes
app.include_router(router, prefix="/api", tags=["simulation"])


@app.on_event("startup")
async def startup_event():
    """Initialize the simulation on startup with config.json values."""
    from backend.config import get_config

    config = get_config()
    engine = get_engine()
    # Use reset() which automatically loads config values
    engine.reset()
    print(f"Village Simulation initialized with {config.world.initial_agents} agents")


@app.get("/", tags=["root"])
def root():
    """Root endpoint - redirect to web frontend."""
    return RedirectResponse(url="/web/")


@app.get("/health", tags=["health"])
def health_check():
    """Health check endpoint."""
    engine = get_engine()
    return {
        "status": "healthy",
        "simulation_running": engine.is_running,
        "agents_alive": len(engine.world.get_living_agents()),
    }


# ============== Web Frontend ==============

@app.get("/web", include_in_schema=False)
def redirect_to_web_frontend():
    """Redirect /web to /web/ for static file serving."""
    return RedirectResponse(url="/web/")


# Mount static files for web frontend (access at http://localhost:8000/web/)
if os.path.exists(WEB_FRONTEND_PATH):
    app.mount("/web", StaticFiles(directory=WEB_FRONTEND_PATH, html=True), name="web_frontend")
else:
    print(f"Warning: Web frontend not found at {WEB_FRONTEND_PATH}")


def main():
    """Run the server."""
    uvicorn.run(
        "backend.main:app",
        host="0.0.0.0",
        port=8000,
        reload=True,
    )


if __name__ == "__main__":
    main()