import abc
import os
from pathlib import Path
import time
from typing import Optional, Any
from dataclasses import dataclass

from lmm.overlayfs import OverlayFSMount
from lmm.profile import Profile
from lmm.steam import find_library_folder_for_game


class CannotStartReason:
    pass


@dataclass
class PathNotExistingReason(CannotStartReason):
    # The path that is not existing
    path: Path

    def __str__(self) -> str:
        return f"Path {self.path} does not exist"


class Game(abc.ABC):
    # The name of the game.
    name: str

    # List of profiles.
    profiles: list[Profile]

    # The default runner to use when launching the game.
    default_runner: Optional["Runner"]

    def __init__(
        self, name: str, profiles: list[Profile], default_runner: Optional["Runner"]
    ):
        self.name = name
        self.profiles = profiles
        self.default_runner = default_runner

    def get_profile_by_name(self, name: str) -> Optional[Profile]:
        for profile in self.profiles:
            if profile.name == name:
                return profile
        return None

    @classmethod
    def from_dict(cls, data: dict[str, Any]) -> "Game":
        raise NotImplementedError()

    def to_dict(self) -> dict[str, Any]:
        raise NotImplementedError()

    def installation_path(self) -> Path:
        raise NotImplementedError()

    def prepare_overlays(self, profile: Profile) -> list[OverlayFSMount]:
        raise NotImplementedError()

    def can_start(self) -> bool:
        return True

    def cannot_start_reasons(self) -> list[CannotStartReason]:
        return []

    def wait(self):
        return None


class ProtonGame(Game, abc.ABC):
    # The appid of the game in Steam.
    appid: str

    # The PID of the game.
    _pid: Optional[str]

    def __init__(
        self,
        name: str,
        appid: str,
        profiles: list[Profile],
        default_runner: Optional["Runner"],
    ):
        super().__init__(name, profiles, default_runner)
        self._pid = None
        self.appid = appid

    def compat_path(self) -> Path:
        raise NotImplementedError()

    @property
    def game_executable(self) -> Path:
        raise NotImplementedError()

    @property
    def steam_library(self) -> Optional[Path]:
        return find_library_folder_for_game(self.appid)

    def wait(self):
        # Wait until we started the game.
        proc = Path("/proc")
        windows_path = str(self.game_executable).replace("/", "\\")
        wine_exe_path = f"Z:{windows_path}"
        print(wine_exe_path)
        print("Polling for game process...")
        while True:
            for dir in os.listdir(proc):
                if not dir.isnumeric():
                    continue

                proc_path = proc / dir / "cmdline"
                try:
                    with open(proc_path, "r") as f:
                        cmdline = f.read()

                    # Workaround for games like Baldur's Gate 3 that have a relative path in the cmdline.
                    # Note that the cmdline contains null bytes that we have to remove.
                    abs_cmdline = os.path.abspath(cmdline).replace("\x00", "")
                    if cmdline.startswith(wine_exe_path) or abs_cmdline == str(
                        self.game_executable
                    ):
                        self._pid = dir
                        break
                except:
                    pass
            if self._pid is not None:
                print(f"Found {self.name} at PID {self._pid}")
                break
            print(".")
            time.sleep(2)
        print()

        # Poll until the game quits.
        print(f"Polling {self._pid}")
        pid_path = proc / self._pid
        while pid_path.exists():
            time.sleep(2)