"""
Handler registry — maps job_type strings to Handler classes.
"""

from typing import Dict, Type

from .handlers.base import Handler

_handlers: Dict[str, Type[Handler]] = {}


def register_handler(job_type: str, handler_class: Type[Handler]) -> None:
    """Register a handler class for a job type."""
    _handlers[job_type] = handler_class


def get_handler(job_type: str) -> Handler:
    """Get an instantiated handler for a job type."""
    if job_type not in _handlers:
        raise ValueError(f"Unknown job type: {job_type}")
    return _handlers[job_type]()


def _register_defaults() -> None:
    """Register built-in handlers."""
    from .handlers.chunk import ChunkHandler
    from .handlers.transcode import TranscodeHandler

    register_handler("transcode", TranscodeHandler)
    register_handler("chunk", ChunkHandler)


_register_defaults()