## Copyright © 2026 Olaf Kolkman
## SPDX-License-Identifier: GPL-3.0-or-later

from urllib.parse import quote
from urllib.error import HTTPError

from fastapi import APIRouter, Depends, HTTPException
from fastapi.responses import RedirectResponse
from starlette.requests import Request

from backend.app.api.dependencies import get_current_user
from backend.app.services.mastodon_oauth import finish_authorization, start_authorization
from backend.app.core.errors import public_error, redacted_error, request_id
import logging

router = APIRouter()
logger = logging.getLogger(__name__)


@router.get('/oauth/start')
def oauth_start(request: Request, instance: str = 'mastodon.social', user: dict = Depends(get_current_user)):
    try:
        authorization_url = start_authorization(user['id'], instance)
    except HTTPError as error:
        retry_after = error.headers.get('Retry-After') if error.headers else None
        headers = {'Retry-After': retry_after} if retry_after else None
        raise HTTPException(
            status_code=error.code,
            detail=f'Mastodon returned HTTP {error.code} while registering LinkLog. Try again later.',
            headers=headers,
        ) from error
    except Exception as error:
        logger.error('Mastodon registration failed request_id=%s error=%s', request_id(request), redacted_error(error))
        raise HTTPException(status_code=502, detail=public_error(request, 'Could not register with Mastodon.')) from error
    return {'authorization_url': authorization_url}


@router.get('/oauth/callback')
def oauth_callback(request: Request, code: str | None = None, state: str | None = None, error: str | None = None):
    if error or not code or not state:
        return RedirectResponse(f'/profile?mastodon_error={quote(error or "Authorization was cancelled")}')
    try:
        finish_authorization(code, state)
    except Exception as callback_error:
        logger.error('Mastodon callback failed request_id=%s error=%s', request_id(request), redacted_error(callback_error))
        return RedirectResponse(f'/profile?mastodon_error={quote(public_error(request, "Could not complete Mastodon authorization."))}')
    return RedirectResponse('/profile?mastodon=connected')