"""
main.py
Application entrypoint.
Starts the FastAPI HTTP server (web UI + REST API) and mounts the FastMCP
streamable-HTTP endpoint under /mcp.
"""

from __future__ import annotations

import logging
from contextlib import asynccontextmanager

import uvicorn
from fastapi import FastAPI, Request
from fastapi.responses import FileResponse, JSONResponse
from fastapi.staticfiles import StaticFiles

from app.api import routes_config, routes_instructions, routes_status
from app.config import settings
from app.database import init_db
from app.logging_setup import configure_logging
from app.mcp_server import mcp, mcp_asgi_app
from app.services import instruction_service

# ---------------------------------------------------------------------------
# Logging must be configured before any module emits log messages
# ---------------------------------------------------------------------------
configure_logging(settings)
logger = logging.getLogger(__name__)


# ---------------------------------------------------------------------------
# Build the FastAPI application
# ---------------------------------------------------------------------------

@asynccontextmanager
async def lifespan(app: FastAPI):
    # Startup
    logger.info("local-mcp starting up – initialising database …")
    init_db(settings.db_path)
    await instruction_service.init_wakeup()
    logger.info(
        "local-mcp ready  http://%s:%d  |  MCP  http://%s:%d/mcp  (stateless=%s)",
        settings.host, settings.http_port,
        settings.host, settings.http_port,
        settings.mcp_stateless,
    )
    # Run the MCP session manager for the duration of the app lifetime
    async with mcp.session_manager.run():
        yield
    # Shutdown
    logger.info("local-mcp shutting down")


def create_app() -> FastAPI:
    app = FastAPI(
        title="local-mcp",
        description="Localhost MCP server with instruction queue management UI",
        version="1.0.0",
        lifespan=lifespan,
    )

    # --- Global exception handler ---
    @app.exception_handler(Exception)
    async def global_exception_handler(request: Request, exc: Exception):
        logger.exception("Unhandled exception for %s %s", request.method, request.url)
        return JSONResponse(
            status_code=500,
            content={"detail": "Internal server error", "error": str(exc)},
        )

    # --- API routers ---
    app.include_router(routes_status.router)
    app.include_router(routes_instructions.router)
    app.include_router(routes_config.router)

    # --- MCP streamable-HTTP transport mounted at /mcp ---
    # mcp_asgi_app was pre-built in mcp_server.py; session manager is
    # started explicitly in the lifespan above.
    app.mount("/mcp", mcp_asgi_app)

    # --- Static files for the web UI ---
    app.mount("/static", StaticFiles(directory="static", html=False), name="static")

    @app.get("/", include_in_schema=False)
    def serve_index():
        return FileResponse("static/index.html")

    return app


app = create_app()


if __name__ == "__main__":
    uvicorn.run(
        "main:app",
        host=settings.host,
        port=settings.http_port,
        log_level=settings.log_level.lower(),
        reload=False,
    )