package service

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

	"eino-project/internal/domain/llm"
	"eino-project/internal/domain/workflow"
	"eino-project/internal/pkg/sseutil"

	"github.com/go-kratos/kratos/v2/log"
	kratoshttp "github.com/go-kratos/kratos/v2/transport/http"
)

type WorkflowService struct {
	models llm.LLM
	log    *log.Helper
}

func NewWorkflowService(logger log.Logger, models llm.LLM) *WorkflowService {
	return &WorkflowService{
		models: models,
		log:    log.NewHelper(logger),
	}
}

func (s *WorkflowService) HandleProductWorkflow(ctx kratoshttp.Context) error {
	type reqType struct {
		Message   string `json:"message"`
		SessionID string `json:"session_id"`
	}
	var req reqType
	if err := json.NewDecoder(ctx.Request().Body).Decode(&req); err != nil {
		return ctx.JSON(http.StatusBadRequest, &CommonResp{Code: http.StatusBadRequest, Msg: "Invalid request body"})
	}

	w := ctx.Response()
	w.Header().Set("Content-Type", "text/event-stream")
	w.Header().Set("Cache-Control", "no-cache")
	w.Header().Set("Connection", "keep-alive")
	fl, ok := w.(http.Flusher)
	if !ok {
		return ctx.JSON(http.StatusInternalServerError, &CommonResp{Code: http.StatusInternalServerError, Msg: "SSE not supported"})
	}

	sseutil.WriteLoading(w, fl, req.SessionID, "开始执行工作流")
	sseutil.WriteProcess(w, fl, req.SessionID, "预处理输入", false)

	wf := workflow.NewZltxProductWorkflow(s.models)
	final, err := wf.Run(context.Background(), req.Message)
	if err != nil {
		sseutil.WriteError(w, fl, req.SessionID, err.Error())
		sseutil.WriteDone(w, fl, req.SessionID)
		return nil
	}

	var comp map[string]interface{}
	if json.Unmarshal([]byte(final), &comp) != nil {
		comp = map[string]interface{}{"result": final}
	}
	sseutil.WriteJson(w, fl, req.SessionID, comp, true)
	sseutil.WriteDone(w, fl, req.SessionID)
	return nil
}