from __future__ import annotations

import time

from fastapi import APIRouter, Depends

from app.api.deps import get_embeddings_service, require_auth
from app.models.schemas import SemanticRouterRequest, SemanticRouterResponse
from app.services.embeddings_service import EmbeddingService
from app.services.semantic_router_service import SemanticRouterService

router = APIRouter()


@router.post(
    "/semantic-router/route",
    response_model=SemanticRouterResponse,
    summary="Route a query to the best matching route using semantic similarity",
)
async def route_query(
    body: SemanticRouterRequest,
    token: str = Depends(require_auth),
    embedding_service: EmbeddingService = Depends(get_embeddings_service),
) -> SemanticRouterResponse:
    start = time.perf_counter()
    svc = SemanticRouterService(embedding_service)
    routes_dict = [r.model_dump() for r in body.routes]
    result = svc.route(body.query, routes_dict, body.threshold)
    elapsed_ms = round((time.perf_counter() - start) * 1000, 3)
    return SemanticRouterResponse(
        success=result["success"],
        time_ms=elapsed_ms,
        name=result.get("name"),
        models=result.get("models", []),
        error=result.get("error"),
        confidence=result.get("confidence"),
        margin=result.get("margin"),
        threshold=result.get("threshold"),
        matched_utterance=result.get("matched_utterance"),
    )