package admin

import (
	"fmt"
	"time"

	"github.com/go-playground/validator/v10"
	"github.com/gofiber/fiber/v2"
	"github.com/google/uuid"
	"github.com/hibiken/asynq"
	"go.uber.org/zap"

	"github.com/break/junhong_cmp_fiber/internal/task"
	"github.com/break/junhong_cmp_fiber/pkg/constants"
	"github.com/break/junhong_cmp_fiber/pkg/errors"
	"github.com/break/junhong_cmp_fiber/pkg/queue"
	"github.com/break/junhong_cmp_fiber/pkg/response"
)

// TaskHandler 任务处理器
type TaskHandler struct {
	queueClient *queue.Client
	logger      *zap.Logger
	validator   *validator.Validate
}

// NewTaskHandler 创建任务处理器实例
func NewTaskHandler(queueClient *queue.Client, logger *zap.Logger) *TaskHandler {
	return &TaskHandler{
		queueClient: queueClient,
		logger:      logger,
		validator:   validator.New(),
	}
}

// SubmitEmailTaskRequest 提交邮件任务请求
type SubmitEmailTaskRequest struct {
	To          string   `json:"to" validate:"required,email"`
	Subject     string   `json:"subject" validate:"required,min=1,max=200"`
	Body        string   `json:"body" validate:"required,min=1"`
	CC          []string `json:"cc,omitempty" validate:"omitempty,dive,email"`
	Attachments []string `json:"attachments,omitempty"`
	RequestID   string   `json:"request_id,omitempty"`
}

// SubmitSyncTaskRequest 提交数据同步任务请求
type SubmitSyncTaskRequest struct {
	SyncType  string `json:"sync_type" validate:"required,oneof=sim_status flow_usage real_name"`
	StartDate string `json:"start_date" validate:"required"`
	EndDate   string `json:"end_date" validate:"required"`
	BatchSize int    `json:"batch_size,omitempty" validate:"omitempty,min=1,max=1000"`
	RequestID string `json:"request_id,omitempty"`
	Priority  string `json:"priority,omitempty" validate:"omitempty,oneof=critical default low"`
}

// TaskResponse 任务响应
type TaskResponse struct {
	TaskID string `json:"task_id"`
	Queue  string `json:"queue"`
	Status string `json:"status"`
}

// SubmitEmailTask 提交邮件发送任务
// @Summary 提交邮件发送任务
// @Description 异步发送邮件
// @Tags 任务
// @Accept json
// @Produce json
// @Param request body SubmitEmailTaskRequest true "邮件任务参数"
// @Success 200 {object} response.Response{data=TaskResponse}
// @Failure 400 {object} response.Response
// @Router /api/v1/tasks/email [post]
func (h *TaskHandler) SubmitEmailTask(c *fiber.Ctx) error {
	var req SubmitEmailTaskRequest
	if err := c.BodyParser(&req); err != nil {
		h.logger.Warn("解析邮件任务请求失败",
			zap.Error(err))
		return errors.New(errors.CodeInvalidParam, "请求参数格式错误")
	}

	// 验证参数
	if err := h.validator.Struct(&req); err != nil {
		h.logger.Warn("邮件任务参数验证失败",
			zap.Error(err))
		return errors.New(errors.CodeInvalidParam, err.Error())
	}

	// 生成 RequestID（如果未提供）
	if req.RequestID == "" {
		req.RequestID = generateRequestID("email")
	}

	// 构造任务载荷
	payload := &task.EmailPayload{
		RequestID:   req.RequestID,
		To:          req.To,
		Subject:     req.Subject,
		Body:        req.Body,
		CC:          req.CC,
		Attachments: req.Attachments,
	}

	// 提交任务到队列
	err := h.queueClient.EnqueueTask(
		c.Context(),
		constants.TaskTypeEmailSend,
		payload,
		asynq.Queue(constants.QueueDefault),
		asynq.MaxRetry(constants.DefaultRetryMax),
		asynq.Timeout(constants.DefaultTimeout),
	)
	if err != nil {
		h.logger.Error("提交邮件任务失败",
			zap.String("to", req.To),
			zap.String("request_id", req.RequestID),
			zap.Error(err))
		return errors.New(errors.CodeInternalError, "任务提交失败")
	}

	h.logger.Info("邮件任务提交成功",
		zap.String("queue", constants.QueueDefault),
		zap.String("to", req.To),
		zap.String("request_id", req.RequestID))

	return response.SuccessWithMessage(c, TaskResponse{
		TaskID: req.RequestID,
		Queue:  constants.QueueDefault,
		Status: "queued",
	}, "邮件任务已提交")
}

// SubmitSyncTask 提交数据同步任务
// @Summary 提交数据同步任务
// @Description 异步执行数据同步
// @Tags 任务
// @Accept json
// @Produce json
// @Param request body SubmitSyncTaskRequest true "同步任务参数"
// @Success 200 {object} response.Response{data=TaskResponse}
// @Failure 400 {object} response.Response
// @Router /api/v1/tasks/sync [post]
func (h *TaskHandler) SubmitSyncTask(c *fiber.Ctx) error {
	var req SubmitSyncTaskRequest
	if err := c.BodyParser(&req); err != nil {
		h.logger.Warn("解析同步任务请求失败",
			zap.Error(err))
		return errors.New(errors.CodeInvalidParam, "请求参数格式错误")
	}

	// 验证参数
	if err := h.validator.Struct(&req); err != nil {
		h.logger.Warn("同步任务参数验证失败",
			zap.Error(err))
		return errors.New(errors.CodeInvalidParam, err.Error())
	}

	// 生成 RequestID（如果未提供）
	if req.RequestID == "" {
		req.RequestID = generateRequestID("sync")
	}

	// 设置默认批量大小
	if req.BatchSize == 0 {
		req.BatchSize = 100
	}

	// 确定队列优先级
	queueName := constants.QueueDefault
	if req.Priority == "critical" {
		queueName = constants.QueueCritical
	} else if req.Priority == "low" {
		queueName = constants.QueueLow
	}

	// 构造任务载荷
	payload := &task.DataSyncPayload{
		RequestID: req.RequestID,
		SyncType:  req.SyncType,
		StartDate: req.StartDate,
		EndDate:   req.EndDate,
		BatchSize: req.BatchSize,
	}

	// 提交任务到队列
	err := h.queueClient.EnqueueTask(
		c.Context(),
		constants.TaskTypeDataSync,
		payload,
		asynq.Queue(queueName),
		asynq.MaxRetry(constants.DefaultRetryMax),
		asynq.Timeout(constants.DefaultTimeout),
	)
	if err != nil {
		h.logger.Error("提交同步任务失败",
			zap.String("sync_type", req.SyncType),
			zap.String("request_id", req.RequestID),
			zap.Error(err))
		return errors.New(errors.CodeInternalError, "任务提交失败")
	}

	h.logger.Info("同步任务提交成功",
		zap.String("queue", queueName),
		zap.String("sync_type", req.SyncType),
		zap.String("request_id", req.RequestID))

	return response.SuccessWithMessage(c, TaskResponse{
		TaskID: req.RequestID,
		Queue:  queueName,
		Status: "queued",
	}, "同步任务已提交")
}

// generateRequestID 生成请求 ID
func generateRequestID(prefix string) string {
	return fmt.Sprintf("%s-%s-%d", prefix, uuid.New().String(), time.Now().UnixNano())
}