"""Backend factory for easy switching between LLM backends."""

from typing import Optional
from .base import LLMBackend
from .ollama import OllamaBackend
from .llama_cpp import LlamaCppBackend


class BackendFactory:
    """Factory for creating LLM backend instances."""

    @staticmethod
    def create_backend(
        backend_type: str = "ollama",
        host: Optional[str] = None,
        model: Optional[str] = None,
        **kwargs,
    ) -> LLMBackend:
        """Create an LLM backend instance.

        Args:
            backend_type: Type of backend ("ollama" or "llama_cpp").
            host: Backend-specific host/connection info.
            model: Model name/path.
            **kwargs: Additional backend-specific arguments.

        Returns:
            LLMBackend instance.
        """
        backend_type = backend_type.lower()

        if backend_type == "ollama":
            return OllamaBackend(
                host=host or "localhost:11434",
                model=model or "codellama",
                temperature=kwargs.get("temperature", 0.1),
                max_tokens=kwargs.get("max_tokens", 500),
            )

        elif backend_type == "llama_cpp":
            return LlamaCppBackend(
                model_path=model or "~/.cache/llama-cpp/models/",
                n_ctx=kwargs.get("n_ctx", 2048),
                n_threads=kwargs.get("n_threads", 4),
                temperature=kwargs.get("temperature", 0.1),
                max_tokens=kwargs.get("max_tokens", 500),
            )

        else:
            raise ValueError(f"Unknown backend type: {backend_type}")

    @staticmethod
    def get_available_backends() -> list[str]:
        """Get list of available backend types.

        Returns:
            List of backend type strings.
        """
        return ["ollama", "llama_cpp"]