package mq

import (
	"encoding/json"
	"fmt"
	"reflect"

	"mongo.games.com/goserver/core/broker"
	"mongo.games.com/goserver/core/broker/rabbitmq"
	"mongo.games.com/goserver/core/logger"

	"mongo.games.com/game/mq/internal"
)

type HandlerFunc func(data interface{}) (err error)

type HandlerData struct {
	T reflect.Type
	F HandlerFunc
}

type MessageMgr struct {
	name    map[reflect.Type]string
	handler map[string]HandlerData
}

type RegisterMessageParam struct {
	Name string
	Data interface{}
}

// RegisterMessage 注册消息
func (c *MessageMgr) RegisterMessage(param *RegisterMessageParam) {
	if param == nil {
		return
	}
	t := c.getType(param.Data)
	c.name[t] = param.Name
}

func (c *MessageMgr) getType(data interface{}) reflect.Type {
	return reflect.Indirect(reflect.ValueOf(data)).Type()
}

func (c *MessageMgr) getName(data interface{}) string {
	t := c.getType(data)
	if name, exist := c.name[t]; exist {
		return name
	}
	return ""
}

type RabbitMQData struct {
	MQName string // 是队列名称也是Routing key
	Data   interface{}
}

func (c *MessageMgr) Send(data interface{}, name ...string) error {
	if msg, ok := data.(*RabbitMQData); ok {
		return Send(msg.MQName, msg.Data)
	}
	if len(name) > 0 && name[0] != "" {
		return Send(name[0], data)
	}
	key := c.getName(data)
	if key == "" {
		key = "_null_"
	}
	return Send(key, data)
}

type RegisterHandlerParam struct {
	Name    string
	Data    interface{}
	Handler HandlerFunc
}

// RegisterHandler 注册消息处理函数
func (c *MessageMgr) RegisterHandler(param *RegisterHandlerParam) {
	if param == nil {
		return
	}
	if _, ok := c.handler[param.Name]; ok {
		panic(fmt.Sprintf("RabbitMQ RegisterHandler repeatet name:%v", param.Name))
		return
	}
	if param.Data == nil {
		return
	}
	if param.Handler == nil {
		return
	}
	c.handler[param.Name] = HandlerData{
		T: c.getType(param.Data),
		F: param.Handler,
	}

	internal.RegisterSubscriber(param.Name, func(e broker.Event) (err error) {
		msg := e.Message()
		if msg != nil {
			defer func() {
				e.Ack()
			}()

			log := reflect.New(c.handler[param.Name].T).Interface()
			err = json.Unmarshal(msg.Body, log)
			if err != nil {
				logger.Logger.Errorf("RabbitMQ Unmarshal error: %v", err)
				return
			}
			logger.Logger.Tracef("MQ Receive[%v]: %#v", param.Name, log)

			return c.handler[param.Name].F(log)
		}
		return nil
	}, broker.Queue(param.Name), broker.DisableAutoAck(), rabbitmq.DurableQueue())
}

// MessageMgrSingle 消息发送器
var MessageMgrSingle = &MessageMgr{
	name:    make(map[reflect.Type]string),
	handler: make(map[string]HandlerData),
}

// RegisterMessage 注册消息
// name: 消息名称
// data: 消息结构体指针
func RegisterMessage(param *RegisterMessageParam) {
	MessageMgrSingle.RegisterMessage(param)
}

// Write 发送消息
// 默认队列名称规则：队列前缀_消息结构体名称
func Write(data interface{}, name ...string) error {
	return MessageMgrSingle.Send(data, name...)
}

// RegisterHandler 注册消息处理函数
func RegisterHandler(param *RegisterHandlerParam) {
	MessageMgrSingle.RegisterHandler(param)
}

var globalConsumer *internal.RabbitMQConsumer

// StartConsumer 启动消费者
func StartConsumer(url string, exchange string, durableExchange bool, opts ...broker.Option) {
	StopConsumer()
	globalConsumer = internal.NewRabbitMQConsumer(url, rabbitmq.Exchange{Name: exchange, Durable: durableExchange}, opts...)
	if err := globalConsumer.Start(); err != nil {
		panic(fmt.Sprintf("RabbitMQConsumer.Start() url:%v exchange:%v err:%v", url, exchange, err))
	}
}

// StopConsumer 停止消费者
func StopConsumer() {
	if globalConsumer != nil {
		globalConsumer.Stop()
	}
}

var globalPublisher *internal.RabbitMQPublisher

// StartPublisher 启动发布者
func StartPublisher(url string, exchange string, durableExchange bool, queueSize int, opts ...broker.Option) {
	StopPublisher()
	globalPublisher = internal.NewRabbitMQPublisher(url, rabbitmq.Exchange{Name: exchange, Durable: durableExchange}, queueSize, opts...)
	if err := globalPublisher.Start(); err != nil {
		panic(fmt.Sprintf("RabbitMQPublisher.Start() url:%v exchange:%v err:%v", url, exchange, err))
	}
}

// StopPublisher 停止发布者
func StopPublisher() {
	if globalPublisher != nil {
		globalPublisher.Stop()
	}
}

func Send(topic string, msg interface{}, opts ...broker.PublishOption) (err error) {
	if globalPublisher != nil {
		logger.Logger.Tracef("MQ Send[%v]: %#v", topic, msg)
		return globalPublisher.Send(topic, msg, opts...)
	}
	logger.Logger.Errorf("RabbitMQPublisher not start!")
	return internal.ErrClosed
}