"""
Supports replacement of static/course/jump-to-id URLs to absolute URLs in XBlocks.
"""

from xblock.reference.plugins import Service

from common.djangoapps.static_replace import (
    replace_course_urls,
    replace_jump_to_id_urls,
    replace_static_urls
)


class ReplaceURLService(Service):
    """
    A service for replacing static/course/jump-to-id URLs with absolute URLs in XBlocks.

    Args:
        block: (optional) An XBlock instance. Used when retrieving the service from the ModuleStoreRuntime.
        static_asset_path: (optional) Path for static assets, which overrides data_directory and course_id, if nonempty
        static_paths_out: (optional) Array to collect tuples for each static URI found:
            * the original unmodified static URI
            * the updated static URI (will match the original if unchanged)
        jump_to_id_base_url: (optional) Absolute path to the base of the handler that will perform the redirect
        lookup_url_func: Lookup function which returns the correct path of the asset
    """
    def __init__(
        self,
        block=None,
        static_asset_path='',
        static_paths_out=None,
        jump_to_id_base_url=None,
        lookup_asset_url=None,
        **kwargs
    ):
        super().__init__(**kwargs)
        self.static_asset_path = static_asset_path
        self.static_paths_out = static_paths_out
        self.jump_to_id_base_url = jump_to_id_base_url
        self.lookup_asset_url = lookup_asset_url
        # This is needed because the `Service` class initialization expects the XBlock passed as an `xblock` keyword
        #  argument, but the `service` method from the `ModuleStoreRuntime` passes a `block`.
        self._xblock = self.xblock() or block

    def replace_urls(self, text, static_replace_only=False):
        """
        Replaces all static/course/jump-to-id URLs in provided text/html.

        Args:
            text: String containing the URL to be replaced
            static_replace_only: If True, only static urls will be replaced
        """
        block = self.xblock()
        if self.lookup_asset_url:
            text = replace_static_urls(text, xblock=block, lookup_asset_url=self.lookup_asset_url)
        else:
            text = replace_static_urls(
                text,
                data_directory=getattr(block, 'data_dir', None),
                course_id=block.scope_ids.usage_id.context_key,
                static_asset_path=self.static_asset_path or block.static_asset_path,
                static_paths_out=self.static_paths_out
            )
            if not static_replace_only:
                text = replace_course_urls(text, block.scope_ids.usage_id.context_key)
                if self.jump_to_id_base_url:
                    text = replace_jump_to_id_urls(text, block.scope_ids.usage_id.context_key, self.jump_to_id_base_url)

        return text