package ai

import (
	"encoding/json"
	"fmt"
	"net/http"

	"github.com/youruser/base/internal/logic/ai"
	"github.com/youruser/base/internal/svc"
	"github.com/youruser/base/internal/types"
	"github.com/zeromicro/go-zero/rest/httpx"
)

func AiChatCompletionsHandler(svcCtx *svc.ServiceContext) http.HandlerFunc {
	return func(w http.ResponseWriter, r *http.Request) {
		var req types.AIChatCompletionRequest
		if err := httpx.ParseJsonBody(r, &req); err != nil {
			httpx.ErrorCtx(r.Context(), w, err)
			return
		}

		l := ai.NewAiChatCompletionsLogic(r.Context(), svcCtx)

		if req.Stream {
			// SSE streaming mode
			w.Header().Set("Content-Type", "text/event-stream")
			w.Header().Set("Cache-Control", "no-cache")
			w.Header().Set("Connection", "keep-alive")
			w.Header().Set("Access-Control-Allow-Origin", "*")

			flusher, ok := w.(http.Flusher)
			if !ok {
				http.Error(w, "streaming not supported", http.StatusInternalServerError)
				return
			}

			streamChan, err := l.ChatStream(&req)
			if err != nil {
				errData, _ := json.Marshal(map[string]string{"error": err.Error()})
				fmt.Fprintf(w, "data: %s\n\n", errData)
				flusher.Flush()
				return
			}

			for chunk := range streamChan {
				data, _ := json.Marshal(chunk)
				fmt.Fprintf(w, "data: %s\n\n", data)
				flusher.Flush()
			}
			fmt.Fprintf(w, "data: [DONE]\n\n")
			flusher.Flush()
		} else {
			// Normal (non-streaming) mode
			resp, err := l.Chat(&req)
			if err != nil {
				httpx.ErrorCtx(r.Context(), w, err)
			} else {
				httpx.OkJsonCtx(r.Context(), w, resp)
			}
		}
	}
}