voice-to-notes/python/voice_to_notes/providers/anthropic_provider.py

"""Anthropic provider — direct Anthropic SDK integration."""

from __future__ import annotations

import os
from typing import Any

from voice_to_notes.providers.base import AIProvider


class AnthropicProvider(AIProvider):
    """Connects to the Anthropic API."""

    def __init__(
        self,
        api_key: str | None = None,
        model: str = "claude-sonnet-4-6",
    ) -> None:
        self._api_key = api_key or os.environ.get("ANTHROPIC_API_KEY", "")
        self._model = model
        self._client: Any = None

    def _ensure_client(self) -> Any:
        if self._client is not None:
            return self._client

        if not self._api_key:
            raise RuntimeError(
                "Anthropic API key not configured. Set ANTHROPIC_API_KEY or provide it in settings."
            )

        try:
            import anthropic

            self._client = anthropic.Anthropic(api_key=self._api_key)
        except ImportError:
            raise RuntimeError("anthropic package is required. Install with: pip install anthropic")
        return self._client

    def chat(self, messages: list[dict[str, str]], **kwargs: Any) -> str:
        client = self._ensure_client()

        # Anthropic expects a system message separately
        system_msg = ""
        chat_messages = []
        for msg in messages:
            if msg.get("role") == "system":
                system_msg = msg.get("content", "")
            else:
                chat_messages.append(msg)

        create_kwargs: dict[str, Any] = {
            "model": kwargs.get("model", self._model),
            "messages": chat_messages,
            "max_tokens": kwargs.get("max_tokens", 2048),
        }
        if system_msg:
            create_kwargs["system"] = system_msg

        response = client.messages.create(**create_kwargs)
        # Anthropic returns content blocks
        return "".join(block.text for block in response.content if hasattr(block, "text"))

    def is_available(self) -> bool:
        return bool(self._api_key)

    @property
    def name(self) -> str:
        return "Anthropic"