import flask
import logging
import sys
import os
from flaskbase.extensions import db
from flaskbase.middleware import MethodRewriteMiddleware

_initializers = set()


def import_submodules(app, submodule):
    ret = list()

    for mod_name in app.config['ENABLED_MODULES']:
        try:
            # FIXME support for mod_name directing to submodule
            mod = __import__('%s.%s' % (mod_name, submodule))
            ret.append((mod_name, getattr(mod, submodule)))
        except ImportError:
            # Check if error occured right in that try clause
            if sys.exc_info()[2].tb_next:
                logging.warning('Import failed for %s.%s', mod_name, submodule,
                                exc_info=True)

    return ret


def create_app(settings_object=None, settings={}):
    app = flask.Flask(
        __name__,
        template_folder='../templates',
        static_folder='../static'
        )

    if 'SETTINGS_MODULE' in os.environ:
        app.config.from_envvar('SETTINGS_MODULE')
    else:
        if not settings_object:
            settings_object = 'flaskbase.settings.{}'.format(
                os.environ.get('ENV', 'production'))

        app.config.from_object(settings_object)

    app.config.update(settings)

    # FIXME https://github.com/mattupstate/flask-social/issues/34
    app.wsgi_app = MethodRewriteMiddleware(app.wsgi_app)

    for m_name, m in import_submodules(app, 'extensions'):
        m.init_app(app)

    import_submodules(app, 'models')

    for m_name, m in import_submodules(app, 'views'):
        app.register_blueprint(
            m.blueprint,
            url_prefix=app.config['URLS'].get(m_name, '/' + m.blueprint.name),
            )

    import_submodules(app, 'admin')

    for fun in _initializers:
        fun(app)

    logging.info('Starting...')
    return app


def initializer(f):
    _initializers.add(f)

    return f


def init_db(app):
    db.create_all()