"""
GameAdapterRegistry — singleton that holds all registered game adapters.
Adapters register themselves at import time.
"""
from __future__ import annotations

import logging

logger = logging.getLogger(__name__)


class GameAdapterRegistry:
    _adapters: dict[str, object] = {}  # game_type -> GameAdapter

    @classmethod
    def register(cls, adapter) -> None:
        """Register a game adapter. Called at import time by each adapter package."""
        if adapter.game_type in cls._adapters:
            logger.warning(
                "Adapter for '%s' already registered. Overwriting.", adapter.game_type
            )
        cls._adapters[adapter.game_type] = adapter
        logger.info("Registered game adapter: %s (%s)", adapter.game_type, adapter.display_name)

    @classmethod
    def get(cls, game_type: str):
        """
        Get adapter by game_type. Raises KeyError if not registered.
        Core code calls this whenever game-specific behavior is needed.
        """
        adapter = cls._adapters.get(game_type)
        if adapter is None:
            raise KeyError(
                f"No adapter registered for game type '{game_type}'. "
                f"Available: {list(cls._adapters.keys())}"
            )
        return adapter

    @classmethod
    def all(cls) -> list:
        """Return all registered adapters."""
        return list(cls._adapters.values())

    @classmethod
    def list_game_types(cls) -> list[dict]:
        """Return metadata list for API /games endpoint."""
        result = []
        for adapter in cls._adapters.values():
            caps = []
            for cap in [
                "config_generator", "process_config", "log_parser",
                "remote_admin", "mission_manager", "mod_manager", "ban_manager",
            ]:
                if adapter.has_capability(cap):
                    caps.append(cap)
            result.append({
                "game_type": adapter.game_type,
                "display_name": adapter.display_name,
                "version": adapter.version,
                "capabilities": caps,
            })
        return result

    @classmethod
    def is_registered(cls, game_type: str) -> bool:
        return game_type in cls._adapters