"""Flask application factory."""
import os
from flask import Flask
from flask_cors import CORS
from app.extensions import db
from app.routes_tunes import tunes_bp
from app.routes_instruments import instruments_bp
from app.routes_sub import sub_bp
from app.routes_sources import sources_bp
from app.routes_musicians import musicians_bp
from app.routes_tunings import tunings_bp


def create_app():
    app = Flask(__name__)

    # --- Config ---
    app.config["SQLALCHEMY_DATABASE_URI"] = os.environ["DATABASE_URL"]
    app.config["SQLALCHEMY_TRACK_MODIFICATIONS"] = False

    # --- CORS ---
    # CORS_ORIGINS in .env is a comma-separated list of allowed origins.
    # Defaults to * for local dev. Lock this down in production to your
    # S3 bucket / CloudFront domain, e.g.:
    #   CORS_ORIGINS=https://yourdomain.com,https://www.yourdomain.com
    raw = os.environ.get("CORS_ORIGINS", "*")
    origins = [o.strip() for o in raw.split(",")] if raw != "*" else "*"
    CORS(app, origins=origins, supports_credentials=False)

    # --- Extensions ---
    db.init_app(app)

    # --- Blueprints ---
    app.register_blueprint(tunes_bp)
    app.register_blueprint(instruments_bp)
    app.register_blueprint(sub_bp)
    app.register_blueprint(sources_bp)
    app.register_blueprint(musicians_bp)
    app.register_blueprint(tunings_bp)

    # --- Error handlers ---
    from sqlalchemy.exc import IntegrityError

    @app.errorhandler(IntegrityError)
    def handle_integrity_error(e):
        db.session.rollback()
        return {"error": "Conflict — duplicate or constraint violation"}, 409

    @app.get("/health")
    def health():
        return {"status": "ok"}

    return app