import json

from anthropic import AsyncAnthropic

from app.services.ai.base import AIProvider, SYSTEM_PROMPT, USER_PROMPT_TEMPLATE


class AnthropicProvider(AIProvider):
    def __init__(self, config: dict) -> None:
        self._client = AsyncAnthropic(api_key=config["api_key"])
        self._model = config.get("model", "claude-haiku-4-5-20251001")

    async def classify_document(self, text: str) -> dict:
        message = await self._client.messages.create(
            model=self._model,
            max_tokens=2048,
            system=SYSTEM_PROMPT,
            messages=[{
                "role": "user",
                "content": USER_PROMPT_TEMPLATE.format(text=text[:100_000]),
            }],
        )
        raw = message.content[0].text.strip()
        return _parse_json(raw)


def _parse_json(raw: str) -> dict:
    # Strip accidental markdown fences despite explicit instruction not to include them
    if raw.startswith("```"):
        raw = raw.split("\n", 1)[1].rsplit("```", 1)[0]
    return json.loads(raw)