package service

import (
	"context"
	"errors"
	"time"

	"model-asynch/dao"
	"model-asynch/model/dto"
	"model-asynch/model/entity"

	"github.com/gogf/gf/v2/database/gdb"
	"github.com/gogf/gf/v2/frame/g"
	"github.com/gogf/gf/v2/os/gtime"
	"github.com/google/uuid"
)

var Task = &taskService{}

type taskService struct{}

func (s *taskService) Create(ctx context.Context, req *dto.CreateTaskReq) (res *dto.CreateTaskRes, err error) {
	startAt := time.Now()
	// 固化 token/user 等信息
	ctx = asyncCtx(ctx)

	// 1) 检查模型配置
	m, err := dao.Model.GetByModelName(ctx, req.ModelName)
	if err != nil {
		return nil, err
	}
	if m == nil || m.Enabled != 1 {
		return nil, errors.New("模型不存在或未启用")
	}

	// 2) 排队上限（近似控制）
	if m.QueueLimit > 0 {
		cnt, err := dao.Task.CountActiveByModel(ctx, req.ModelName)
		if err != nil {
			return nil, err
		}
		if cnt >= int64(m.QueueLimit) {
			return nil, errors.New("任务排队已满，请稍后再试")
		}
	}

	taskID := uuid.NewString()
	// 将调用模型的 payload 与透传头信息一起存入 request_payload，供后台 worker 使用
	storedPayload := map[string]any{
		"payload": req.RequestPayload,
		"headers": forwardHeaders(ctx),
	}

	t := &entity.AsynchTask{
		ModelName:      req.ModelName,
		TaskID:         taskID,
		State:          0,
		InputRef:       req.InputRef,
		RequestPayload: storedPayload,
	}
	_, err = dao.Task.Insert(ctx, t)
	if err != nil {
		return nil, err
	}

	// 3) 写操作日志（尽量不影响主流程，失败忽略）
	ip := ""
	ua := ""
	apiPath := "/task/createTask"
	httpMethod := "POST"
	if r := g.RequestFromCtx(ctx); r != nil {
		ip = r.GetClientIp()
		ua = r.UserAgent()
		apiPath = r.URL.Path
		httpMethod = r.Method
	}
	_, _ = dao.OpLog.Insert(ctx, &entity.AsynchOpLog{
		IP:             ip,
		UserAgent:      ua,
		APIPath:        apiPath,
		HttpMethod:     httpMethod,
		BizName:        req.BizName,
		ModelName:      req.ModelName,
		TaskID:         taskID,
		OpType:         "createTask",
		Success:        1,
		ErrorMsg:       "",
		CostMs:         time.Since(startAt).Milliseconds(),
		RequestPayload: storedPayload,
		ResponsePayload: gdb.Map{
			"taskId": taskID,
		},
	})
	return &dto.CreateTaskRes{TaskID: taskID}, nil
}

func (s *taskService) GetResult(ctx context.Context, taskID string) (res *dto.GetTaskResultRes, err error) {
	t, err := dao.Task.GetByTaskID(ctx, taskID)
	if err != nil {
		return nil, err
	}
	if t == nil {
		return nil, errors.New("任务不存在")
	}
	return &dto.GetTaskResultRes{
		OssFile: t.OssFile,
		State:   t.State,
	}, nil
}

// GetBatch 批量查询任务；将成功(state=2)的任务更新为已下载(state=4)，并写入过期时间
func (s *taskService) GetBatch(ctx context.Context, req *dto.GetTaskBatchReq) (res *dto.GetTaskBatchRes, err error) {
	if req == nil || len(req.TaskIDs) == 0 {
		return &dto.GetTaskBatchRes{List: []dto.GetTaskBatchItem{}}, nil
	}
	// 1) 先查当前租户下的任务列表
	list, err := dao.Task.ListByTaskIDs(ctx, req.TaskIDs)
	if err != nil {
		return nil, err
	}

	// 2) 对成功(state=2)的任务：标记为已下载(state=4)并写入 expire_at
	now := time.Now()
	for _, t := range list {
		if t == nil {
			continue
		}
		if t.State != 2 {
			continue
		}
		// 按模型配置决定保留时间
		m, err := dao.Model.GetByModelName(ctx, t.ModelName)
		if err != nil {
			return nil, err
		}
		retainSeconds := 86400
		if m != nil && m.AutoCleanSeconds > 0 {
			retainSeconds = m.AutoCleanSeconds
		}
		expireAt := gtime.New(now.Add(time.Duration(retainSeconds) * time.Second))
		_ = dao.Task.MarkDownloadedByID(ctx, t.Id, expireAt)

		// 为了本次返回一致性，内存里也更新
		t.State = 4
		t.ExpireAt = expireAt
	}

	// 3) 组装返回
	items := make([]dto.GetTaskBatchItem, 0, len(list))
	for _, t := range list {
		if t == nil {
			continue
		}
		items = append(items, dto.GetTaskBatchItem{
			TaskID:  t.TaskID,
			State:   t.State,
			OssFile: t.OssFile,
		})
	}
	return &dto.GetTaskBatchRes{List: items}, nil
}

func (s *taskService) List(ctx context.Context, req *dto.ListTaskReq) (res *dto.ListTaskRes, err error) {
	pageNum, pageSize := 1, 10
	if req != nil && req.Page != nil {
		if req.Page.PageNum > 0 {
			pageNum = int(req.Page.PageNum)
		}
		if req.Page.PageSize > 0 {
			pageSize = int(req.Page.PageSize)
		}
	}
	modelName := ""
	taskID := ""
	var state *int
	if req != nil {
		modelName = req.ModelName
		taskID = req.TaskID
		state = req.State
	}
	list, total, err := dao.Task.List(ctx, pageNum, pageSize, modelName, taskID, state)
	if err != nil {
		return nil, err
	}
	return &dto.ListTaskRes{List: list, Total: total}, nil
}