import os
import platform
import tarfile
from pathlib import Path
import shutil
import aiohttp
import asyncio

from aiopath import AsyncPath

from worthless import constants
from worthless.launcher import Launcher
from worthless.installer import Installer

match platform.system():
    case "Linux":
        from worthless import linux
    case "Windows":
        pass  # TODO
    case "Darwin":
        pass  # TODO

NO_XDELTA3_MODULE = False
try:
    import xdelta3
except ImportError:
    NO_XDELTA3_MODULE = True


class Patcher:
    def __init__(self, gamedir: Path | AsyncPath | str = AsyncPath.cwd(), data_dir: str | Path | AsyncPath = None,
                 patch_url: str = None, overseas=True):
        if isinstance(gamedir, str | Path):
            gamedir = AsyncPath(gamedir)
        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 = constants.APPDIRS
            self._patch_path = AsyncPath(self._appdirs.user_data_dir).joinpath("Patch")
            self._temp_path = AsyncPath(self._appdirs.user_cache_dir).joinpath("Patcher")
        else:
            if isinstance(data_dir, str | Path):
                data_dir = AsyncPath(data_dir)
            self._patch_path = data_dir.joinpath("Patch")
            self._temp_path = data_dir.joinpath("Temp/Patcher")
        self._overseas = overseas
        self._installer = Installer(self._gamedir, overseas=overseas, data_dir=data_dir)
        self._launcher = Launcher(self._gamedir, overseas=overseas)
        match platform.system():
            case "Linux":
                self._linux = linux.LinuxUtils()

    @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()

    async def _download_repo(self, fallback=False):
        if shutil.which("git") and not fallback:
            if not await self._patch_path.is_dir() or not await self._patch_path.joinpath(".git").exists():
                proc = await asyncio.create_subprocess_exec("git", "clone", self._patch_url, str(self._patch_path))
            else:
                proc = await asyncio.create_subprocess_exec("git", "pull", cwd=str(self._patch_path))
            await proc.wait()
            if proc.returncode != 0:
                raise RuntimeError("Cannot download patch repository through git.")
        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()

    async def is_telemetry_blocked(self, optional=False):
        """
        Check if the telemetry is blocked.

        """
        if self._overseas:
            telemetry_url = constants.TELEMETRY_URL_LIST
        else:
            telemetry_url = constants.TELEMETRY_URL_CN_LIST
        if optional:
            telemetry_url |= constants.TELEMETRY_OPTIONAL_URL_LIST
        unblocked_list = []
        async with aiohttp.ClientSession() as session:
            for url in telemetry_url:
                try:
                    await session.get("https://" + url, timeout=15)
                except (aiohttp.ClientResponseError, aiohttp.ClientConnectorError, asyncio.exceptions.TimeoutError):
                    continue
                else:
                    unblocked_list.append(url)
        return None if not unblocked_list else unblocked_list

    async def block_telemetry(self, optional=False):
        telemetry = await self.is_telemetry_blocked(optional)
        if not telemetry:
            raise ValueError("All telemetry are blocked")
        telemetry_hosts = "\n"
        for url in telemetry:
            telemetry_hosts += "0.0.0.0 " + url + "\n"
        match platform.system():
            case "Linux":
                await self._linux.append_text_to_file(telemetry_hosts, "/etc/hosts")
                return
        # TODO: Windows and macOS
        raise NotImplementedError("Platform not implemented.")

    async def _patch_unityplayer_fallback(self, patch):
        gamever = "".join((await self._installer.get_game_version()).split("."))
        unity_path = self._gamedir.joinpath("UnityPlayer.dll")
        await unity_path.rename(self._gamedir.joinpath("UnityPlayer.dll.bak"))
        proc = await asyncio.create_subprocess_exec("xdelta3", "-d", "-s",
                                                    str(self._gamedir.joinpath("UnityPlayer.dll.bak")),
                                                    str(self._patch_path.joinpath(
                                                        "{}/patch_files/{}".format(gamever, patch))),
                                                    str(self._gamedir.joinpath("UnityPlayer.dll")), cwd=self._gamedir)
        await proc.wait()

    async def _patch_xlua_fallback(self, patch):
        gamever = "".join((await self._installer.get_game_version()).split("."))
        data_name = self._installer.get_game_data_name()
        xlua_path = self._gamedir.joinpath("{}/Plugins/xlua.dll".format(data_name))
        await xlua_path.rename(self._gamedir.joinpath("{}/Plugins/xlua.dll.bak".format(data_name)))
        proc = await asyncio.create_subprocess_exec("xdelta3", "-d", "-s",
                                                    str(self._gamedir.joinpath(
                                                        "{}/Plugins/xlua.dll.bak".format(data_name))),
                                                    str(self._patch_path.joinpath(
                                                        "{}/patch_files/{}".format(gamever, patch))),
                                                    str(self._gamedir.joinpath(
                                                        "{}/Plugins/xlua.dll".format(data_name))),
                                                    cwd=self._gamedir)
        await proc.wait()

    async def _patch_unityplayer(self, patch):
        gamever = "".join((await self._installer.get_game_version()).split("."))
        unity_path = self._gamedir.joinpath("UnityPlayer.dll")
        patch_bytes = self._patch_path.joinpath("{}/patch_files/{}".format(gamever, patch)).read_bytes()
        patched_unity_bytes = xdelta3.decode(unity_path.read_bytes(), patch_bytes)
        unity_path.rename(self._gamedir.joinpath("UnityPlayer.dll.bak"))
        with Path(self._gamedir.joinpath("UnityPlayer.dll")).open("wb") as f:
            f.write(patched_unity_bytes)

    async def _patch_xlua(self, patch):
        gamever = "".join((await self._installer.get_game_version()).split("."))
        data_name = self._installer.get_game_data_name()
        xlua_path = self._gamedir.joinpath("{}/Plugins/xlua.dll".format(data_name))
        patch_bytes = self._patch_path.joinpath("{}/patch_files/{}".format(gamever, patch)).read_bytes()
        patched_xlua_bytes = xdelta3.decode(xlua_path.read_bytes(), patch_bytes)
        xlua_path.rename(self._gamedir.joinpath("{}/Plugins/xlua.dll.bak".format(data_name)))
        with Path(self._gamedir.joinpath("{}/Plugins/xlua.dll".format(data_name))).open("wb") as f:
            f.write(patched_xlua_bytes)

    async def apply_xlua_patch(self, fallback=True):
        if self._overseas:
            patch = "xlua_patch_os.vcdiff"
        else:
            patch = "xlua_patch_cn.vcdiff"
        if NO_XDELTA3_MODULE or fallback:
            await self._patch_xlua_fallback(patch)
            return
        await self._patch_xlua(patch)

    async def apply_patch(self, crash_fix=False, fallback=True) -> None:
        """
        Patch the game (and optionally patch xLua if specified)

        :param fallback:
        :param crash_fix: Whether to patch xLua or not
        :return: None
        """
        # Patch UnityPlayer.dll
        # xdelta3-python doesn't work because it's outdated.
        if self._overseas:
            patch = "unityplayer_patch_os.vcdiff"
        else:
            patch = "unityplayer_patch_cn.vcdiff"
        patch_jobs = []
        if NO_XDELTA3_MODULE or fallback:
            patch_jobs.append(self._patch_unityplayer_fallback(patch))
        else:
            patch_jobs.append(self._patch_unityplayer(patch))
        # Patch xLua.dll
        if crash_fix:
            patch_jobs.append(self.apply_xlua_patch(fallback=fallback))
        # Disable crash reporters

        async def disable_crashreporters():
            disable_files = [
                self._installer.get_game_data_name() + "upload_crash.exe",
                self._installer.get_game_data_name() + "Plugins/crashreport.exe",
            ]
            for file in disable_files:
                file_path = Path(file).resolve()
                if file_path.exists():
                    file_path.rename(str(file_path) + ".bak")

        patch_jobs.append(disable_crashreporters())
        await asyncio.gather(*patch_jobs)

    @staticmethod
    async def _creation_date(file_path: AsyncPath):
        """
        Try to get the date that a file was created, falling back to when it was
        last modified if that isn't possible.
        See http://stackoverflow.com/a/39501288/1709587 for explanation.
        """
        if platform.system() == 'Windows':
            return os.path.getctime(file_path)
        else:
            stat = await file_path.stat()
            try:
                return stat.st_birthtime
            except AttributeError:
                # We're probably on Linux. No easy way to get creation dates here,
                # so we'll settle for when its content was last modified.
                return stat.st_mtime

    async def _revert_file(self, original_file: str, base_file: AsyncPath, ignore_error=False):
        original_path = await self._gamedir.joinpath(original_file + ".bak").resolve()
        target_file = await self._gamedir.joinpath(original_file).resolve()
        if await original_path.exists():
            if abs(await self._creation_date(base_file) - await self._creation_date(original_path)) > 86400:  # 24 hours
                if not ignore_error:
                    raise RuntimeError("{} is not for this game version.".format(original_path.name))
                original_path.unlink(missing_ok=True)
            else:
                target_file.unlink(missing_ok=True)
                original_path.rename(target_file)

    async def revert_patch(self, ignore_errors=True) -> None:
        """
        Revert the patch (and revert the xLua patch if patched)

        :return: None
        """
        game_exec = self._gamedir.joinpath((await self._launcher.get_resource_info()).game.latest.entry)
        revert_files = [
            "UnityPlayer.dll",
            self._installer.get_game_data_name() + "upload_crash.exe",
            self._installer.get_game_data_name() + "Plugins/crashreport.exe",
            self._installer.get_game_data_name() + "Plugins/xlua.dll",
        ]
        revert_job = []
        for file in revert_files:
            revert_job.append(self._revert_file(file, game_exec, ignore_errors))
        for file in ["launcher.bat", "mhyprot2_running.reg"]:
            revert_job.append(self._gamedir.joinpath(file).unlink(missing_ok=True))

        async def get_files(extensions):
            all_files = []
            for ext in extensions:
                all_files.extend(await self._gamedir.glob(ext))
            return all_files

        files = await get_files(('*.dxvk-cache', '*_d3d9.log', '*_d3d11.log', '*_dxgi.log'))
        for file in files:
            revert_job.append(file.unlink(missing_ok=True))

        await asyncio.gather(*revert_job)

    async def clear_cache(self):
        await asyncio.to_thread(shutil.rmtree, self._temp_path, ignore_errors=True)