import base64
import binascii

import uvicorn
from fastapi import FastAPI
import casbin

from core.config import settings
from starlette.middleware.cors import CORSMiddleware
from starlette.authentication import AuthenticationBackend, AuthenticationError, SimpleUser, AuthCredentials
from starlette.middleware.authentication import AuthenticationMiddleware


from db import connect_to_mongo, close_mongo_connection

app = FastAPI(title=settings.PROJECT_NAME)

if settings.BACKEND_CORS_ORIGINS:
    app.add_middleware(
        CORSMiddleware,
        allow_origins=['*'],
        allow_credentials=True,
        allow_methods=["*"],
        allow_headers=["*"],
    )
app.add_event_handler("startup", connect_to_mongo)
app.add_event_handler("shutdown", close_mongo_connection)


class BasicAuth(AuthenticationBackend):
    async def authenticate(self, request):
        if "Authorization" not in request.headers:
            return None

        auth = request.headers["Authorization"]
        try:
            scheme, credentials = auth.split()
            decoded = base64.b64decode(credentials).decode("ascii")
        except (ValueError, UnicodeDecodeError, binascii.Error):
            raise AuthenticationError("Invalid basic auth credentials")

        username, _, password = decoded.partition(":")
        return AuthCredentials(["authenticated"]), SimpleUser(username)

# enforcer = casbin.Enforcer('rbac_model.conf', 'rbac_policy.csv')
# app.add_middleware(CasbinMiddleware, enforcer=enforcer)
# app.add_middleware(AuthenticationMiddleware, backend=BasicAuth())

from api.api_v1.api import api_router

app.include_router(api_router, prefix=settings.API_V1_STR)

if __name__ == '__main__':
    uvicorn.run(app='main:app', host="0.0.0.0", port=8889, reload=True, debug=True)