"""Command registry and dispatcher."""

from collections.abc import Awaitable, Callable
from dataclasses import dataclass, field

from mudlib.player import Player

# Type alias for command handlers
CommandHandler = Callable[[Player, str], Awaitable[None]]


@dataclass
class CommandDefinition:
    """Metadata wrapper for a registered command."""

    name: str
    handler: CommandHandler
    aliases: list[str] = field(default_factory=list)
    mode: str = "normal"
    help: str = ""
    hidden: bool = False


# Registry maps command names to definitions
_registry: dict[str, CommandDefinition] = {}


def register(defn: CommandDefinition) -> None:
    """Register a command definition with its aliases.

    Args:
        defn: The command definition to register
    """
    _registry[defn.name] = defn
    for alias in defn.aliases:
        _registry[alias] = defn


async def dispatch(player: Player, raw_input: str) -> None:
    """Parse input, find command, call handler.

    Args:
        player: The player executing the command
        raw_input: The raw input string from the player
    """
    raw_input = raw_input.strip()

    if not raw_input:
        return

    # Split into command and arguments
    parts = raw_input.split(maxsplit=1)
    command = parts[0].lower()
    args = parts[1] if len(parts) > 1 else ""

    # Look up the definition
    defn = _registry.get(command)

    if defn is None:
        player.writer.write(f"Unknown command: {command}\r\n")
        await player.writer.drain()
        return

    # Check mode restriction
    if defn.mode != "*" and defn.mode != player.mode:
        player.writer.write("You can't do that right now.\r\n")
        await player.writer.drain()
        return

    # Execute the handler
    await defn.handler(player, args)