import os
from logging.config import dictConfig

from flask import Flask
from flask_migrate import Migrate, upgrade
from flask_sqlalchemy import SQLAlchemy

from corvus import utility

db: SQLAlchemy = SQLAlchemy()

dictConfig({
    'version': 1,
    'formatters': {'default': {
        'format': '[%(asctime)s] %(levelname)s in %(module)s: %(message)s',
    }},
    'handlers': {'wsgi': {
        'class': 'logging.StreamHandler',
        'stream': 'ext://flask.logging.wsgi_errors_stream',
        'formatter': 'default'
    }},
    'root': {
        'level': 'INFO',
        'handlers': ['wsgi']
    }
})


def create_app(test_config: dict = None) -> Flask:
    app = Flask(__name__, instance_relative_config=True)
    app.logger.debug('Creating Corvus Server')

    data_directory = os.getenv('CORVUS_DATA_DIRECTORY', '/tmp')
    app.logger.debug('Corvus Data Directory: %s', data_directory)

    default_database_uri = 'sqlite:///{}/corvus.db'.format(data_directory)
    app.config.from_mapping(
        SECRET_KEY='dev',
        SQLALCHEMY_DATABASE_URI=default_database_uri,
        SQLALCHEMY_TRACK_MODIFICATIONS=False
    )

    if test_config is None:
        app.logger.debug('Loading configurations')
        app.config.from_object('corvus.default_settings')
        app.config.from_pyfile('config.py', silent=True)
        if os.getenv('CORVUS_SETTINGS', None):
            app.config.from_envvar('CORVUS_SETTINGS')
    else:
        app.logger.debug('Loading test configuration')
        app.config.from_object(test_config)

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

    app.json_encoder = utility.CustomJSONEncoder

    app.logger.debug('Initializing Application')
    db.init_app(app)
    app.logger.debug('Registering Database Models')
    Migrate(app, db)

    return app


def register_blueprints(app: Flask) -> None:
    from corvus.api import auth_blueprint
    app.register_blueprint(auth_blueprint)


app = create_app()
register_blueprints(app)


def init_db() -> None:
    """Clear existing data and create new tables."""
    upgrade('migrations')


if __name__ == "__main__":
    app.run()