from fastapi import APIRouter, HTTPException, Depends
import httpx
import json

from ..config import settings
from ..models import SummarizeRequest, SummarizeResponse, ActionItemCreate, TokenPayload
from .auth import get_current_user

router = APIRouter()


@router.post("/ai/summarize", response_model=SummarizeResponse)
async def summarize_transcript(
    request: SummarizeRequest, current_user: TokenPayload = Depends(get_current_user)
):
    """
    Send transcript to Dify for AI summarization.
    Returns structured conclusions and action items.
    """
    if not settings.DIFY_API_KEY:
        raise HTTPException(status_code=503, detail="Dify API not configured")

    async with httpx.AsyncClient() as client:
        try:
            response = await client.post(
                f"{settings.DIFY_API_URL}/chat-messages",
                headers={
                    "Authorization": f"Bearer {settings.DIFY_API_KEY}",
                    "Content-Type": "application/json",
                },
                json={
                    "inputs": {},
                    "query": request.transcript,
                    "response_mode": "blocking",
                    "user": current_user.email,
                },
                timeout=120.0,  # Long timeout for LLM processing
            )

            if response.status_code != 200:
                raise HTTPException(
                    status_code=response.status_code,
                    detail=f"Dify API error: {response.text}",
                )

            data = response.json()
            answer = data.get("answer", "")

            # Try to parse structured JSON from Dify response
            parsed = parse_dify_response(answer)

            return SummarizeResponse(
                conclusions=parsed["conclusions"],
                action_items=[
                    ActionItemCreate(
                        content=item.get("content", ""),
                        owner=item.get("owner", ""),
                        due_date=item.get("due_date"),
                    )
                    for item in parsed["action_items"]
                ],
            )

        except httpx.TimeoutException:
            raise HTTPException(
                status_code=504, detail="Dify API timeout - transcript may be too long"
            )
        except httpx.RequestError as e:
            raise HTTPException(status_code=503, detail=f"Dify API unavailable: {str(e)}")


def parse_dify_response(answer: str) -> dict:
    """
    Parse Dify response to extract conclusions and action items.
    Attempts JSON parsing first, then falls back to text parsing.
    """
    # Try to find JSON in the response
    try:
        # Look for JSON block
        if "```json" in answer:
            json_start = answer.index("```json") + 7
            json_end = answer.index("```", json_start)
            json_str = answer[json_start:json_end].strip()
        elif "{" in answer and "}" in answer:
            # Try to find JSON object
            json_start = answer.index("{")
            json_end = answer.rindex("}") + 1
            json_str = answer[json_start:json_end]
        else:
            raise ValueError("No JSON found")

        data = json.loads(json_str)
        return {
            "conclusions": data.get("conclusions", []),
            "action_items": data.get("action_items", []),
        }
    except (ValueError, json.JSONDecodeError):
        # Fallback: return raw answer as single conclusion
        return {
            "conclusions": [answer] if answer else [],
            "action_items": [],
        }