"""
Exposes Django utilities for consumption in the xmodule library
NOTE: This file should only be imported into 'django-safe' code, i.e. known that this code runs int the Django
runtime environment with the djangoapps in common configured to load
"""


from os import listdir

import webpack_loader
# NOTE: we are importing this method so that any module that imports us has access to get_current_request
from crum import get_current_request
from django.conf import settings
from webpack_loader.loader import WebpackLoader


class XModuleWebpackLoader(WebpackLoader):
    """
    Custom webpack loader that consumes the output generated by webpack-bundle-tracker
    and the files from XModule style generation stage. Briefly, this allows to use the
    generated js bundles and compiled assets for XModule-style during Xblocks rendering.
    """

    def load_assets(self):
        """
        This function will append XModule css files to the standard load_assets results.

        The standard WebpackLoader load_assets method returns a dictionary like the following:

            {
                'status': 'done',
                'chunks': {
                    'AnnotatableBlockPreview': [
                        {
                            'name': 'AnnotatableBlockPreview.js',
                            'path': '/openedx/edx-platform/common/static/bundles/AnnotatableBlockPreview.js'
                        },
                        {
                            'name': 'AnnotatableBlockPreview.js.map',
                            'path': '/openedx/edx-platform/common/static/bundles/AnnotatableBlockPreview.js.map'
                        }
                    ],
                    ...
                }
            }

        Chunks key contains the data for every file in /openedx/edx-platform/common/static/bundles/, that
        is a folder created during the compilation theme, this method will append the listed files in
        common/static/css/xmodule to the correspondent key, the result will be the following:

            {
                'status': 'done',
                'chunks': {
                    'AnnotatableBlockPreview': [
                        {
                            'name': 'AnnotatableBlockPreview.js',
                            'path': '/openedx/edx-platform/common/static/bundles/AnnotatableBlockPreview.js'
                        },
                        {
                            'name': 'AnnotatableBlockPreview.js.map',
                            'path': '/openedx/edx-platform/common/static/bundles/AnnotatableBlockPreview.js.map'
                        },
                        {
                            'name': 'AnnotatableBlockPreview.css',
                            'path': 'common/static/css/xmodule/AnnotatableBlockPreview.css',
                            'publicPath': '/static/css/xmodule/AnnotatableBlockPreview.css'
                        }
                    ],
                    ...
                }
            }

        Returns:
            dict: Assets dictionary as described above.
        """
        assets = super().load_assets()

        css_path = "common/static/css/xmodule"
        css_files = listdir(css_path)

        for css_file in css_files:
            name = css_file.split(".")[0]
            css_chunk = {
                "name": css_file,
                "path": f"{css_path}/{css_file}",
                "publicPath": f"{settings.STATIC_URL}css/xmodule/{css_file}",
            }
            assets["chunks"][name].append(css_chunk)

        return assets


def get_current_request_hostname():
    """
    This method will return the hostname that was used in the current Django request
    """
    hostname = None
    request = get_current_request()
    if request:
        hostname = request.META.get('HTTP_HOST')

    return hostname


def add_webpack_to_fragment(fragment, bundle_name, extension=None, config='DEFAULT'):
    """
    Add all webpack chunks to the supplied fragment as the appropriate resource type.
    """
    for chunk in webpack_loader.utils.get_files(bundle_name, extension, config):
        if chunk['name'].endswith(('.js', '.js.gz')):
            fragment.add_javascript_url(chunk['url'])
        elif chunk['name'].endswith(('.css', '.css.gz')):
            fragment.add_css_url(chunk['url'])