import asyncio
import tarfile
import constants
import appdirs
import aiofiles
from pathlib import Path
import shutil
import aiohttp


class Patcher:
    def __init__(self, gamedir=Path.cwd(), data_dir: str | Path = None, patch_url: str = None):
        self._gamedir = gamedir
        self._patch_url = (patch_url if patch_url else constants.PATCH_GIT_URL).replace('http://', 'https://')
        if not data_dir:
            self._appdirs = appdirs.AppDirs(constants.APP_NAME, constants.APP_AUTHOR)
            self._patch_path = Path(self._appdirs.user_data_dir).joinpath("Patch")
            self._temp_path = Path(self._appdirs.user_cache_dir)
        else:
            if not isinstance(data_dir, Path):
                override_data_dir = Path(data_dir)
            self._patch_path = data_dir.joinpath("Patch")
            self._temp_path = data_dir.joinpath("Temp")

    @staticmethod
    async def _get(url, **kwargs) -> aiohttp.ClientResponse:
        async with aiohttp.ClientSession() as session:
            rsp = await session.get(url, **kwargs)
            rsp.raise_for_status()
            return rsp

    async def _get_git_archive(self, archive_format="tar.gz", branch="master"):
        """
        Get the git archive of the patch repository.
        This supports Gitea API and also introduce workaround for https://notabug.org

        :return: Archive file in bytes
        """
        # Replace http with https
        if self._patch_url.startswith('https://notabug.org'):
            archive_url = self._patch_url + '/archive/master.{}'.format(archive_format)
            return await (await self._get(archive_url)).read()
        try:
            url_split = self._patch_url.split('//')
            git_server = url_split[0]
            git_owner, git_repo = url_split[1].split('/')
            archive_url = git_server + '/api/v1/repos/{}/{}/archive/{}.{}'.format(
                git_owner, git_repo, branch, archive_format
            )
            archive = await self._get(archive_url)
        except aiohttp.ClientResponseError:
            pass
        else:
            return await archive.read()
        return

    async def _download_repo(self):
        if shutil.which("git"):
            if not self._patch_path.exists() or not self._patch_path.is_dir() \
                    or not self._patch_path.joinpath(".git").exists():
                await asyncio.create_subprocess_exec("git", "clone", self._patch_url, str(self._patch_path))
            else:
                await asyncio.create_subprocess_exec("git", "pull", cwd=str(self._patch_path))
        else:
            archive = await self._get_git_archive()
            if not archive:
                raise RuntimeError("Cannot download patch repository")

            with tarfile.open(archive) as tar:
                tar.extractall(self._patch_path)

    def override_patch_url(self, url) -> None:
        """
        Override the patch url.

        :param url: Patch repository url, the url must be a valid git repository.
        :return: None
        """
        self._patch_url = url

    async def download_patch(self) -> None:
        """
        If `git` exists, this will clone the patch git url and save it to a temporary directory.
        Else, this will download the patch from the patch url and save it to a temporary directory. (Not reliable)

        :return: None
        """
        await self._download_repo()

    def apply_patch(self, crash_fix=False) -> None:
        """
        Patch the game (and optionally patch the login door crash fix if specified)

        :param crash_fix: Whether to patch the login door crash fix or not
        :return: None
        """
        pass

    def revert_patch(self):
        """
        Revert the patch (and revert the login door crash fix if patched)

        :return: None
        """
        pass