"""Flask web application main script"""

import os
import secrets
from pathlib import Path

from flask import Flask


def create_app() -> Flask:
    """Flask app factory function"""

    root = Path('..')
    static = str(root / 'static')
    tmpl = str(root / 'templates')

    app = Flask(
        __name__,
        static_folder=static,
        template_folder=tmpl,
        instance_relative_config=True,
    )
    app.config['SECRET_KEY'] = os.getenv(
        'SECRET_KEY',
        secrets.token_hex(32),
    )

    try:
        os.makedirs(app.instance_path)
    except OSError:
        pass

    return app