import os

from flask import Flask
from flaskpages import pages
import logging
from flask_flatpages import pygments_style_defs
def create_app(test_config=None):
    """Create and configure an instance of the Flask application."""
    app = Flask(__name__, instance_relative_config=True)
    app.config.from_mapping(
        # a default secret that should be overridden by instance config
        SECRET_KEY="dev", 
        URL_PREFIX = "/"
    )

    if not test_config:
        # load the instance config, if it exists, when not testing
        app.config.from_pyfile("cfg.py")
    else:
        # load the test config if passed in
        app.config.update(test_config)

    # ensure the instance folder exists
    try:
        os.makedirs(app.instance_path)
    except OSError:
        pass
    
    if app.config["DEBUG"]:
        app.logger.setLevel(logging.DEBUG)
    @app.route("/hello")
    def hello():
        return "Hello, World!"

    app.logger.debug(app.config)
    app.register_blueprint(pages.create_bp(app), url_prefix = app.config["URL_PREFIX"], static_folder='static')

    @app.route('/pygments.css')
    def pygments_css():
        return pygments_style_defs('tango'), 200, {'Content-Type': 'text/css'}
    
    app.add_url_rule("/", endpoint="index")

    return app