import logging
import os
import sys
import warnings

from flask import Flask

from tofu_api.api import TofuApiBlueprint
from tofu_api.common.config import Config
from tofu_api.common.json import JSONProvider
from tofu_api.common.rest import RestApiErrorHandler
from tofu_api.dependencies import Dependencies

# Enable deprecation warnings in dev environment
if not sys.warnoptions and os.getenv('FLASK_DEBUG'):
    warnings.filterwarnings('default', module='tofu_api.*')


class App(Flask):
    """
    Flask application for Tofu API.
    """
    # Override Flask classes
    config_class = Config
    json_provider_class = JSONProvider

    # Set type hint for config
    config: Config

    # Dependencies container
    dependencies: Dependencies

    def __init__(self):
        # Set instance path to the project root directory
        project_root_dir = os.path.abspath('.')

        # Create and configure the app
        super().__init__(
            'tofu_api',
            instance_path=project_root_dir,
            instance_relative_config=True,
        )

        # Load app configuration from YAML file
        self.config.from_yaml(os.getenv('FLASK_CONFIG_FILE', default='config.yml'))

        # Configure logging and error handling
        self.configure_logging()
        self.configure_error_handling()

        # Initialize DI container
        self.dependencies = Dependencies()

        # Initialize dependencies
        self.init_database()

        # Register blueprints
        self.register_blueprint(TofuApiBlueprint(self))

    def configure_logging(self) -> None:
        """
        Configures the logging system.
        """
        logging.basicConfig(
            level=logging.DEBUG if self.debug else logging.INFO,
            format='{asctime}.{msecs:03.0f} {levelname:>8} [{name}] {message}',
            datefmt='%Y-%m-%d %H:%M:%S',
            style='{',
        )

    def configure_error_handling(self) -> None:
        """
        Registers error handlers to the app.
        """
        error_handler = RestApiErrorHandler(debug_mode=self.debug)
        error_handler.register_error_handlers(self)

    def init_database(self) -> None:
        """
        Initialize database connection and models.
        """
        # Initialize SQLAlchemy, create the database engine based on the app config
        db = self.dependencies.get_sqlalchemy()
        db.init_database(self)

        # Import models to populate the database metadata
        import tofu_api.models  # noqa (unused import)


def create_app() -> App:
    """
    App factory, returns a Flask app object.
    """
    return App()