from __future__ import annotations

import json
import logging

from fastapi import FastAPI
from fastapi.middleware.cors import CORSMiddleware
from fastapi.responses import FileResponse
from fastapi.staticfiles import StaticFiles
from pathlib import Path
from pydantic import BaseModel
from sse_starlette.sse import EventSourceResponse

from src.config import settings
from src.pipeline import generate_slide

logging.basicConfig(level=getattr(logging, settings.log_level, logging.DEBUG))
logger = logging.getLogger(__name__)

app = FastAPI(title="Design Agent", version="0.1.0")


@app.on_event("startup")
async def startup_preload():
    """서버 시작 시 FAISS 인덱스 + 임베딩 모델 미리 로드."""
    try:
        from src.block_search import _ensure_loaded
        _ensure_loaded()
        logger.info("FAISS 인덱스 + bge-m3 모델 미리 로드 완료")
    except Exception as e:
        logger.warning(f"FAISS 미리 로드 실패 (첫 요청 시 로드): {e}")

app.add_middleware(
    CORSMiddleware,
    allow_origins=["http://localhost:5174", "http://localhost:5173"],
    allow_methods=["*"],
    allow_headers=["*"],
)

# 정적 파일 서빙 (CSS, 폰트 등)
static_dir = Path(__file__).parent.parent / "static"
if static_dir.exists():
    app.mount("/static", StaticFiles(directory=str(static_dir)), name="static")


class SlideRequest(BaseModel):
    content: str
    base_path: str = ""  # 이미지 기준 폴더 경로 (선택, 로컬 경로)


@app.get("/api/health")
async def health():
    return {"status": "ok", "service": "design-agent"}


@app.post("/api/generate")
async def generate(req: SlideRequest):
    """콘텐츠 → 슬라이드 생성 (SSE 스트리밍)."""
    async def event_stream():
        async for event in generate_slide(req.content, base_path=req.base_path):
            yield {
                "event": event["event"],
                "data": json.dumps(event["data"], ensure_ascii=False),
            }

    return EventSourceResponse(event_stream())


@app.get("/")
async def frontend():
    """프론트엔드 UI — static/index.html 서빙."""
    return FileResponse(str(static_dir / "index.html"), media_type="text/html")