import logging
import os
from logging.handlers import RotatingFileHandler

from flask import Flask

from backend.config import FRONTEND_DIST, LOG_DIR, PORT, SECRET_KEY_PATH, STATIC_DIR
from backend.routes.api import api_bp
from backend.routes.spa import spa_bp

os.makedirs(LOG_DIR, exist_ok=True)
os.makedirs(STATIC_DIR, exist_ok=True)


def _load_secret_key():
    secret = os.environ.get("SECRET_KEY")
    if not secret and os.path.exists(SECRET_KEY_PATH):
        with open(SECRET_KEY_PATH, "rb") as f:
            secret = f.read()
    if not secret:
        secret = os.urandom(24)
        with open(SECRET_KEY_PATH, "wb") as f:
            f.write(secret)
    return secret


def create_app():
    app = Flask(__name__)
    app.secret_key = _load_secret_key()

    handler = RotatingFileHandler(
        os.path.join(LOG_DIR, "app.log"),
        maxBytes=1024 * 1024 * 10,
        backupCount=5,
        encoding="utf-8",
    )
    handler.setLevel(logging.INFO)
    handler.setFormatter(logging.Formatter("%(asctime)s - %(levelname)s - %(message)s"))
    app.logger.addHandler(handler)
    app.logger.setLevel(logging.INFO)

    app.register_blueprint(api_bp)
    app.register_blueprint(spa_bp)
    return app