/*
我们使用腾讯云的CMQ作为公司的消息队列基础服务
产品的说明文档：https://cloud.tencent.com/document/product/406
*/
package mqMgr

import (
	"encoding/json"
	"errors"
	"fmt"
	"strings"

	. "Framework/mqMgr/model"
	"goutil/webUtil"
)

const (
	EMPTY_MESSAGE_ERROR          = "消息为空"
	EMPTY_HANDLE_ERROR           = "句柄为空"
	MIN_DELAY_SECONDS            = 0
	MIN_POLLING_WAIT_SECONDS     = 0
	MAX_POLLING_WAIT_SECONDS     = 30
	MAX_BATCH_COUNT              = 16
	EMPTY_BATCH_LIST_ERROR       = "批量消息为空"
	EXCEED_MAX_BATCH_COUNT_ERROR = "批量消息数量超过上限，最多为16条"
)

// Queue对象
type Queue struct {
	// 地域
	region string

	// 网络类型：内网、外网
	network string

	// 队列名称
	queueName string

	// API密钥Id
	secretId string

	// API密钥key
	secretKey string
}

// 执行操作
func (this *Queue) action(requestObj IRequest, responseObj interface{}) error {
	requestObj.SetCommonRequest(NewCommonRequest(requestObj.GetActionName(), this.region, this.secretId, this.queueName))

	// 组装请求url
	paramMap := requestObj.AssembleParamMap()
	url, signature, err := AssembleUrl(this.region, this.network, MQ_TYPE_QUEUE, this.secretKey, paramMap)
	if err != nil {
		return err
	}
	paramMap["Signature"] = signature

	//请求url,请求头
	header := webUtil.GetFormHeader()
	transport := webUtil.NewTransport()
	transport.DisableKeepAlives = true
	transport = webUtil.GetTimeoutTransport(transport, 10)

	statusCode, result, err := webUtil.PostMapData(url, paramMap, header, transport)
	//statusCode, result, err := webUtil.PostMapData(url, paramMap, header, nil)
	if err != nil {
		return err
	}
	if statusCode != 200 {
		return fmt.Errorf("Wrong status from server:%d", statusCode)
	}

	// 解析请求结果
	err = json.Unmarshal(result, responseObj)

	return err
}

// 处理发送消息延迟的时间
func (this *Queue) handleDelaySeconds(delaySeconds int) int {
	if delaySeconds < MIN_DELAY_SECONDS {
		delaySeconds = MIN_DELAY_SECONDS
	}

	return delaySeconds
}

// 处理当没有消息是轮询等待的时间
func (this *Queue) handlePollingWaitSeconds(pollingWaitSeconds int) int {
	if pollingWaitSeconds < MIN_POLLING_WAIT_SECONDS {
		pollingWaitSeconds = MIN_POLLING_WAIT_SECONDS
	} else if pollingWaitSeconds > MAX_POLLING_WAIT_SECONDS {
		pollingWaitSeconds = MAX_POLLING_WAIT_SECONDS
	}

	return pollingWaitSeconds
}

// 验证批量处理的列表
func (this *Queue) validBatchList(list []string) error {
	if list == nil || len(list) == 0 {
		return errors.New(EMPTY_BATCH_LIST_ERROR)
	}
	if len(list) > MAX_BATCH_COUNT {
		return errors.New(EXCEED_MAX_BATCH_COUNT_ERROR)
	}

	return nil
}

// error:错误对象
func (this *Queue) GetQueueAttributes() (err error) {
	// 逻辑处理
	requestObj := NewGetQueueAttributesRequest()
	responseObj := NewGetQueueAttributesResponse()

	// 发送请求
	err = this.action(requestObj, &responseObj)
	if err != nil {
		return
	}

	if responseObj.IsFailure() {
		err = errors.New(responseObj.Message)
		return
	}

	return
}

// SendMessage 发送单条消息
// 参数
// message:消息内容
// delaySeconds:单位为秒，表示该消息发送到队列后，需要延时多久用户才可见该消息。
// 返回值
// error:错误对象
func (this *Queue) SendMessage(message string, delaySeconds int) (err error) {
	// 参数验证和处理
	if message == "" {
		err = errors.New(EMPTY_MESSAGE_ERROR)
		return
	}
	delaySeconds = this.handleDelaySeconds(delaySeconds)

	// 逻辑处理
	requestObj := NewSendMessageRequest(message, delaySeconds)
	responseObj := NewSendMessageResponse()

	// 发送请求
	err = this.action(requestObj, &responseObj)
	if err != nil {
		return
	}

	if responseObj.IsFailure() {
		err = errors.New(responseObj.Message)
		return
	}

	return
}

// BatchSendMessage 批量发送消息
// 参数
// messageList:消息内容列表
// delaySeconds:单位为秒，表示该消息发送到队列后，需要延时多久用户才可见该消息。
// 返回值
// error:错误对象
func (this *Queue) BatchSendMessage(messageList []string, delaySeconds int) (err error) {
	// 参数验证和处理
	err = this.validBatchList(messageList)
	if err != nil {
		return
	}
	delaySeconds = this.handleDelaySeconds(delaySeconds)

	// 逻辑处理
	requestObj := NewBatchSendMessageRequest(messageList, delaySeconds)
	responseObj := NewBatchSendMessageResponse()

	// 发送请求
	err = this.action(requestObj, &responseObj)
	if err != nil {
		return
	}

	if responseObj.IsFailure() {
		err = errors.New(responseObj.Message)
		return
	}

	return
}

// Receive 消费单条消息
// pollingWaitSeconds:本次请求的长轮询等待时间。取值范围0 - 30秒，如果不设置该参数，则默认使用队列属性中的 pollingWaitSeconds 值。
// 返回值
// receiptHandle:消息句柄
// message:消息内容
// exist:是否存在数据
// err:错误对象
func (this *Queue) ReceiveMessage(pollingWaitSeconds int) (receiptHandle, message string, exist bool, err error) {
	// 参数验证和处理
	pollingWaitSeconds = this.handlePollingWaitSeconds(pollingWaitSeconds)

	// 逻辑处理
	requestObj := NewReceiveMessageRequest(pollingWaitSeconds)
	responseObj := NewReceiveMessageResponse()

	// 发送请求
	err = this.action(requestObj, &responseObj)
	if err != nil {
		return
	}

	// 忽略掉没有消息的错误
	if responseObj.HaveNoMessage() {
		return
	}

	if responseObj.IsFailure() {
		err = errors.New(responseObj.Message)
		return
	}

	receiptHandle = responseObj.ReceiptHandle
	message = responseObj.MsgBody
	exist = true

	return
}

// BatchReceiveMessage 批量消费消息
// 参数
// numOfMsg:本次消费的消息数量
// pollingWaitSeconds:本次请求的长轮询等待时间。取值范围0 - 30秒，如果不设置该参数，则默认使用队列属性中的 pollingWaitSeconds 值。
// 返回值
// receiptHandleList:消息句柄列表
// messageList:消息内容列表
// exist:是否存在数据
// err:错误对象
func (this *Queue) BatchReceiveMessage(numOfMsg, pollingWaitSeconds int) (receiptHandleList, messageList []string, exist bool, err error) {
	// 参数验证和处理
	if numOfMsg > MAX_BATCH_COUNT {
		err = errors.New(EXCEED_MAX_BATCH_COUNT_ERROR)
		return
	}
	pollingWaitSeconds = this.handlePollingWaitSeconds(pollingWaitSeconds)

	// 逻辑处理
	requestObj := NewBatchReceiveMessageRequest(numOfMsg, pollingWaitSeconds)
	responseObj := NewBatchReceiveMessageResponse()

	// 发送请求
	err = this.action(requestObj, &responseObj)
	if err != nil {
		return
	}

	// 忽略掉没有消息的错误
	if responseObj.HaveNoMessage() {
		return
	}

	if responseObj.IsFailure() {
		err = errors.New(responseObj.Message)
		return
	}

	// 组装返回
	receiptHandleList = make([]string, 0, numOfMsg)
	messageList = make([]string, 0, numOfMsg)
	for _, msgInfo := range responseObj.MsgInfoList {
		receiptHandleList = append(receiptHandleList, msgInfo.ReceiptHandle)
		messageList = append(messageList, msgInfo.MsgBody)
	}
	exist = true

	return
}

// DeleteMessage 删除单条消息
// 参数
// receiptHandle:消息句柄
// 返回值
// error:错误对象
func (this *Queue) DeleteMessage(receiptHandle string) (err error) {
	// 参数验证和处理
	if receiptHandle == "" {
		err = errors.New(EMPTY_HANDLE_ERROR)
		return
	}

	// 逻辑处理
	requestObj := NewDeleteMessageRequest(receiptHandle)
	responseObj := NewDeleteMessageResponse()

	// 发送请求
	err = this.action(requestObj, &responseObj)
	if err != nil {
		return err
	}

	if responseObj.IsFailure() {
		err = errors.New(responseObj.Message)
		return
	}

	return
}

// BatchDeleteMessage 批量删除消息
// 参数
// receiptHandleList:消息句柄列表
// 返回值
// errorMap:删除错误的字典(key:删除失败的消息句柄;value:删除失败的原因)
// err:错误对象
func (this *Queue) BatchDeleteMessage(receiptHandleList []string) (errorMap map[string]string, err error) {
	// 参数验证和处理
	err = this.validBatchList(receiptHandleList)
	if err != nil {
		return
	}

	// 逻辑处理
	requestObj := NewBatchDeleteMessageRequest(receiptHandleList)
	responseObj := NewBatchDeleteMessageResponse()

	// 发送请求
	err = this.action(requestObj, &responseObj)
	if err != nil {
		return
	}

	if responseObj.IsFailure() {
		err = errors.New(responseObj.Message)
		// 组装返回
		errorMap = make(map[string]string)
		for _, errInfo := range responseObj.ErrorList {
			errorMap[errInfo.ReceiptHandle] = errInfo.Message
		}
		return
	}

	return
}

// 创建新的Queue对象
func NewQueue(region, queueName, secretId, secretKey string) *Queue {
	queueConfigObj := &QueueConfig{
		Region:    region,
		QueueName: queueName,
		SecretId:  secretId,
		SecretKey: secretKey,
	}

	return NewQueueByConfig(queueConfigObj)
}

// 通过队列配置对象创建新的Queue对象
func NewQueueByConfig(queueConfigObj *QueueConfig) *Queue {
	queueObj := &Queue{
		region:    queueConfigObj.Region,
		network:   MQ_NETWORK_INTERNAL,
		queueName: queueConfigObj.QueueName,
		secretId:  queueConfigObj.SecretId,
		secretKey: queueConfigObj.SecretKey,
	}

	err := queueObj.GetQueueAttributes()
	if err != nil {
		if strings.Contains(err.Error(), MQ_NETWORK_INTERNAL) {
			queueObj.network = MQ_NETWORK_PUBLIC
		}
	}

	return queueObj
}