import logging
import os
import uvicorn
from contextlib import asynccontextmanager
from fastapi import FastAPI
from fastapi.middleware.cors import CORSMiddleware
from fastapi.responses import RedirectResponse
from app.api.routers.chat import chat_router
from app.api.routers.user import user_router
from app.settings import init_settings
from fastapi.staticfiles import StaticFiles
from alembic.config import Config
from alembic import command


from app.engine.postgresdb import postgresdb
from config.index import config

logger = logging.getLogger("uvicorn")


def run_migrations(connection, cfg):
    cfg.attributes["connection"] = connection
    command.upgrade(cfg, "head")


async def run_async_migrations():
    logger.info("Running migrations...")
    async_engine = postgresdb.get_engine()

    async with async_engine.begin() as conn:
        await conn.run_sync(run_migrations, Config("alembic.ini"))

    logger.info("Finished running migrations")


@asynccontextmanager
async def lifespan(app_: FastAPI):
    yield
    if postgresdb.get_engine() is not None:
        await postgresdb.close()


init_settings()
# init_observability()


def init_app():
    app = FastAPI(lifespan=lifespan)
    if config.ENVIRONMENT == "dev":
        logger.warning("Running in development mode - allowing CORS for all origins")
        app.add_middleware(
            CORSMiddleware,
            allow_origins=["*"],
            allow_credentials=True,
            allow_methods=["*"],
            allow_headers=["*"],
        )

    if os.path.exists("data"):
        app.mount("/api/data", StaticFiles(directory="data"), name="static")
    app.include_router(chat_router, prefix="/api/chat")
    app.include_router(user_router)

    return app


app = init_app()

if __name__ == "__main__":
    # Redirect to documentation page when accessing base URL
    @app.get("/")
    async def redirect_to_docs():
        return RedirectResponse(url="/docs")

    uvicorn.run(app="main:app", host=config.APP_HOST, port=config.APP_PORT, reload=(config.ENVIRONMENT == "dev"))