"""
Extraction sidecar — FastAPI app running LangExtract.

Internal service, not exposed externally. Called by the Fastify extraction-service.
Default port: 4006.
"""

from __future__ import annotations

import os

import structlog
import uvicorn
from fastapi import FastAPI, HTTPException, Request

from .cache import extraction_cache
from .extractor import extract
from .models import (
    BatchExtractRequest,
    ExtractRequest,
    ExtractResponse,
    HealthResponse,
)

logger = structlog.get_logger(__name__)

app = FastAPI(
    title="Extraction Sidecar",
    description="Internal LangExtract sidecar for extraction-service",
    version="0.1.0",
)


@app.get("/health")
async def health():
    base = HealthResponse()
    return {**base.model_dump(), "cache": extraction_cache.stats}


@app.post("/extract", response_model=ExtractResponse)
async def extract_endpoint(req: ExtractRequest, request: Request) -> ExtractResponse:
    request_id = request.headers.get("x-request-id", "")

    logger.info(
        "extract_request",
        task_id=req.task_id,
        model_id=req.model_id,
        text_length=len(req.text),
        request_id=request_id,
    )

    # Check cache first
    cached = extraction_cache.get(req.text, req.task_id, req.model_id)
    if cached is not None:
        logger.info("cache_hit", task_id=req.task_id, request_id=request_id)
        return cached

    try:
        result = await extract(
            text=req.text,
            task_prompt=req.task_prompt,
            examples=[e.model_dump() for e in req.examples] if req.examples else None,
            model_id=req.model_id,
            extraction_passes=req.extraction_passes,
            max_workers=req.max_workers,
            max_char_buffer=req.max_char_buffer,
        )
        extraction_cache.put(req.text, req.task_id, req.model_id, result)
        return result
    except Exception as exc:
        logger.error("extract_failed", error=str(exc), request_id=request_id)
        raise HTTPException(status_code=500, detail=str(exc)) from exc


@app.post("/extract/batch", response_model=list[ExtractResponse])
async def extract_batch_endpoint(
    batch: BatchExtractRequest,
    request: Request,
) -> list[ExtractResponse]:
    request_id = request.headers.get("x-request-id", "")

    logger.info(
        "batch_extract_request",
        input_count=len(batch.requests),
        request_id=request_id,
    )

    results: list[ExtractResponse] = []
    for req in batch.requests:
        try:
            result = await extract(
                text=req.text,
                task_prompt=req.task_prompt,
                examples=[e.model_dump() for e in req.examples] if req.examples else None,
                model_id=req.model_id,
                extraction_passes=req.extraction_passes,
                max_workers=req.max_workers,
                max_char_buffer=req.max_char_buffer,
            )
            results.append(result)
        except Exception as exc:
            logger.error("batch_item_failed", error=str(exc), request_id=request_id)
            raise HTTPException(status_code=500, detail=str(exc)) from exc

    return results


def main() -> None:
    port = int(os.environ.get("SIDECAR_PORT", "4006"))
    host = os.environ.get("SIDECAR_HOST", "0.0.0.0")

    logger.info("sidecar_starting", port=port, host=host)

    uvicorn.run(
        "src.app:app",
        host=host,
        port=port,
        reload=os.environ.get("NODE_ENV") == "development",
        log_level="info",
    )


if __name__ == "__main__":
    main()