from typing import Any

from markdown import Markdown

from jweb.content import Content, ContentField
from jweb.context import Context


def load_extension(context: Context) -> None:
    context.add_filters(markdown=_MarkdownDocument)


class _MarkdownDocument:
    def __init__(self, content: Content[Any]) -> None:
        if not isinstance(content, Content) or not isinstance(content.data, (str, bytes)):
            raise ValueError("markdown filter can only accept byte or string content")

        data = content.data
        if isinstance(data, bytes):
            data = data.decode("utf-8")

        assert isinstance(data, str)

        self.__content = content
        self.__markdown = Markdown(extensions=["full_yaml_metadata"])
        self.__html = self.__markdown.convert(data)

    @property
    def html(self) -> str:
        return self.__html

    @property
    def meta(self) -> Any:
        return ContentField(self.__content.path, self.__markdown.Meta, self.__content.language)  # type: ignore