from __future__ import annotations

import logging
from datetime import timedelta
from logging.handlers import RotatingFileHandler
from pathlib import Path

from flask import Flask

from .services import Office365Service
from .settings import Settings, load_settings
from .tasks import BackgroundTaskManager


def _configure_logging(app: Flask) -> None:
    log_dir = Path(app.root_path).parent / "logs"
    log_dir.mkdir(parents=True, exist_ok=True)
    log_path = log_dir / "office365_admin.log"

    root_logger = logging.getLogger()
    formatter = logging.Formatter("%(asctime)s [%(levelname)s] %(name)s - %(message)s")

    if not any(isinstance(handler, RotatingFileHandler) for handler in root_logger.handlers):
        file_handler = RotatingFileHandler(
            log_path,
            maxBytes=2 * 1024 * 1024,
            backupCount=5,
            encoding="utf-8",
        )
        file_handler.setFormatter(formatter)
        root_logger.addHandler(file_handler)

    root_logger.setLevel(logging.INFO)
    app.logger.info("Logging initialized at %s", log_path)


def create_app(
    settings_override: Settings | None = None,
    service_factory=None,
    task_manager_factory=None,
) -> Flask:
    settings = settings_override or load_settings()
    app = Flask(__name__, template_folder="templates", static_folder="static")
    app.config["SETTINGS"] = settings
    app.config["JSON_AS_ASCII"] = False
    app.secret_key = settings.session_secret
    app.permanent_session_lifetime = timedelta(hours=8)
    _configure_logging(app)

    if service_factory is None:
        service = Office365Service(settings)
    elif callable(service_factory):
        service = service_factory(settings)
    else:
        service = service_factory

    app.extensions["office365_service"] = service
    if task_manager_factory is None:
        task_manager = BackgroundTaskManager()
    elif callable(task_manager_factory):
        task_manager = task_manager_factory()
    else:
        task_manager = task_manager_factory
    app.extensions["task_manager"] = task_manager

    from .routes import bp

    app.register_blueprint(bp)
    return app