from __future__ import annotations

import json
import secrets
from pathlib import Path

from flask import Flask

from .routes import ui


def _load_secret_key(conf_path: Path) -> str:
    default_key = secrets.token_hex(32)

    if not conf_path.exists():
        return default_key

    try:
        payload = json.loads(conf_path.read_text(encoding="utf-8"))
    except Exception:
        return default_key

    value = payload.get("secret_key") if isinstance(payload, dict) else None
    if isinstance(value, str) and value.strip():
        return value.strip()
    return default_key


def create_app() -> Flask:
    app = Flask(__name__)

    frontend_root = Path(__file__).resolve().parents[1]
    project_root = Path(__file__).resolve().parents[2]
    conf_path = frontend_root / "data" / "conf.json"

    app.config["PROJECT_ROOT"] = project_root
    app.config["MUSIC_DIR"] = project_root / "backend" / "data" / "musiques"
    app.secret_key = _load_secret_key(conf_path)

    app.register_blueprint(ui)
    return app