"""Define API routes for perception (regulatory intelligence)."""

from __future__ import annotations

import json

from fastapi import APIRouter, Query
from fastapi.responses import StreamingResponse

from app.shared.bootstrap import get_perception_service
from app.shared.async_utils import iter_in_thread

router = APIRouter(prefix="/perception", tags=["智能感知"])


@router.get("/stats")
async def get_perception_stats():
    """Return KPI statistics for the perception dashboard."""
    return get_perception_service().get_stats()


@router.get("/events")
async def list_events(
    source: str | None = Query(default=None, description="来源筛选 (MIIT/UN-ECE/ISO/国标委/EUR-Lex/IATF)"),
    impact_level: str | None = Query(default=None, description="影响等级 (high/medium/low)"),
    limit: int = Query(default=50, ge=1, le=100),
):
    """Return regulatory events with optional filters."""
    events = get_perception_service().list_events(
        source=source,
        impact_level=impact_level,
        limit=limit,
    )
    return {"events": events, "total": len(events)}


@router.get("/events/{event_id}")
async def get_event(event_id: str):
    """Return a single regulatory event by ID."""
    event = get_perception_service().get_event(event_id)
    if event is None:
        from fastapi import HTTPException
        raise HTTPException(status_code=404, detail=f"Event {event_id} not found")
    return event


@router.post("/events/{event_id}/analyze")
async def analyze_event(event_id: str):
    """Stream SSE impact analysis for a regulatory event."""
    service = get_perception_service()

    async def event_stream():
        async for item in iter_in_thread(service.analyze_event(event_id)):
            event_name = item.get("event", "message")
            data = item.get("data", "")
            if isinstance(data, (dict, list)):
                data = json.dumps(data, ensure_ascii=False)
            yield f"event: {event_name}\ndata: {data}\n\n"

    return StreamingResponse(
        event_stream(),
        media_type="text/event-stream",
        headers={
            "Cache-Control": "no-cache",
            "X-Accel-Buffering": "no",
        },
    )