import os

# From flask tutorial,
# https://flask.palletsprojects.com/en/3.0.x/tutorial/factory/
from flask import Flask

# https://flask-cors.readthedocs.io/en/latest/
from flask_cors import CORS

# Factory for creating the app object.  Available throughout the app.
def create_app(test_config=None):
    # create and configure the app
    app = Flask(__name__, instance_relative_config=True)
    app.config.from_mapping(
        SECRET_KEY='dev',
        DATABASE=os.path.join(app.instance_path, 'msgcollect.sqlite'),
    )

    # Adds cross-origin permission to everything.
    CORS(app)

    # 
    if test_config is None:
        # load the instance config, if it exists, when not testing
        app.config.from_pyfile('config.py', silent=True)
    else:
        # load the test config if passed in
        app.config.from_mapping(test_config)
    
    # ensure the instance folder exists
    try:
        os.makedirs(app.instance_path)
    except OSError:
        pass

    # a simple page that says hello
    @app.route('/hello')
    def hello():
        return 'Hello, World!'

    from . import db
    db.init_app(app)

    from . import poll
    poll.mk_poll(app)

    from . import add
    add.mk_add(app)

#    from . import altgreet
#    altgreet.mk_alt(app)

    return app