Epic Patient API MCP Server

"""Factory for creating LLM clients."""
import os
from .base import LLMClient
from .gemini import GeminiClient
from .openrouter import OpenRouterClient


def create_llm_client() -> LLMClient:
    """Create an LLM client based on environment variables.

    Checks for LLM_PROVIDER environment variable to determine which client to create.
    Falls back to Gemini if not specified.

    Environment variables:
        LLM_PROVIDER: "gemini" or "openrouter" (default: "gemini")
        GEMINI_API_KEY: Required if using Gemini
        GEMINI_MODEL: Optional model name for Gemini (default: "gemini-2.0-flash-exp")
        OPENROUTER_API_KEY: Required if using OpenRouter
        OPENROUTER_MODEL: Optional model name for OpenRouter (default: "anthropic/claude-3.5-sonnet")

    Returns:
        Configured LLM client

    Raises:
        ValueError: If required API key is not set
    """
    provider = os.getenv("LLM_PROVIDER", "gemini").lower()

    if provider == "openrouter":
        api_key = os.getenv("OPENROUTER_API_KEY")
        if not api_key:
            raise ValueError("OPENROUTER_API_KEY not set")

        model = os.getenv("OPENROUTER_MODEL", "anthropic/claude-3.5-sonnet")
        return OpenRouterClient(api_key=api_key, model=model)

    else:  # Default to Gemini
        api_key = os.getenv("GEMINI_API_KEY")
        if not api_key:
            raise ValueError("GEMINI_API_KEY not set")

        model = os.getenv("GEMINI_MODEL", "gemini-2.0-flash-exp")
        return GeminiClient(api_key=api_key, model=model)