package redis

import (
	"git.sxidc.com/go-framework/baize/framework/core/infrastructure/logger"
	"git.sxidc.com/go-framework/baize/framework/core/infrastructure/message_queue/common"
	"github.com/pkg/errors"
	"github.com/robinjoseph08/redisqueue/v2"
	"strings"
	"sync"
)

const (
	messageValuesDataKey = "data"
)

type Option func(options *Options)

type Options struct {
	MaxLen      int64
	ConsumerNum int
}

func WithMaxLen(maxLen int64) Option {
	return func(options *Options) {
		options.MaxLen = maxLen
	}
}

func WithConsumerNum(consumerNum int) Option {
	return func(options *Options) {
		options.ConsumerNum = consumerNum
	}
}

type MessageQueue struct {
	redisOptions *redisqueue.RedisOptions

	producerMapMutex *sync.Mutex
	producerMap      map[string]*redisqueue.Producer

	consumerMapMutex *sync.Mutex
	consumerMap      map[string]*redisqueue.Consumer

	options *Options
}

func New(address string, userName string, password string, db int, opts ...Option) *MessageQueue {
	options := new(Options)

	for _, opt := range opts {
		opt(options)
	}

	if options.MaxLen == 0 {
		options.MaxLen = 1000
	}

	if options.ConsumerNum == 0 {
		options.ConsumerNum = 10
	}

	return &MessageQueue{
		redisOptions: &redisqueue.RedisOptions{
			Addr:     address,
			Username: userName,
			Password: password,
			DB:       db,
		},
		producerMapMutex: &sync.Mutex{},
		producerMap:      make(map[string]*redisqueue.Producer),
		consumerMapMutex: &sync.Mutex{},
		consumerMap:      make(map[string]*redisqueue.Consumer),
		options:          options,
	}
}

func Destroy(messageQueue *MessageQueue) {
	if messageQueue.redisOptions == nil {
		return
	}

	messageQueue.producerMapMutex.Lock()
	defer messageQueue.producerMapMutex.Unlock()

	messageQueue.producerMap = nil

	messageQueue.consumerMapMutex.Lock()
	defer messageQueue.consumerMapMutex.Unlock()

	for _, consumer := range messageQueue.consumerMap {
		consumer.Shutdown()
		consumer = nil
	}

	messageQueue.consumerMap = nil
}

func (messageQueue *MessageQueue) Subscribe(group string, topic string, handler common.MessageHandler) error {
	messageQueue.consumerMapMutex.Lock()
	defer messageQueue.consumerMapMutex.Unlock()

	groupTopic := messageQueue.formGroupTopic(group, topic)

	_, ok := messageQueue.consumerMap[groupTopic]
	if ok {
		return nil
	}

	newConsumer, err := redisqueue.NewConsumerWithOptions(&redisqueue.ConsumerOptions{
		GroupName:    group,
		Concurrency:  messageQueue.options.ConsumerNum,
		RedisClient:  nil,
		RedisOptions: messageQueue.redisOptions,
	})
	if err != nil {
		return err
	}

	newConsumer.Register(topic, func(message *redisqueue.Message) error {
		data, ok := message.Values[messageValuesDataKey].(string)
		if !ok {
			logger.GetInstance().Error(errors.New("数据不存在"))
			return nil
		}

		handler(messageQueue, message.Stream, data)
		return nil
	})

	go newConsumer.Run()

	messageQueue.consumerMap[groupTopic] = newConsumer
	return nil
}

func (messageQueue *MessageQueue) UnSubscribe(group string, topic string) error {
	messageQueue.consumerMapMutex.Lock()
	defer messageQueue.consumerMapMutex.Unlock()

	groupTopic := messageQueue.formGroupTopic(group, topic)

	consumer, ok := messageQueue.consumerMap[groupTopic]
	if !ok {
		return nil
	}

	consumer.Shutdown()
	delete(messageQueue.consumerMap, groupTopic)

	return nil
}

func (messageQueue *MessageQueue) Publish(topic string, data string) error {
	messageQueue.producerMapMutex.Lock()
	defer messageQueue.producerMapMutex.Unlock()

	producer, err := messageQueue.getProducerNoLock(topic)
	if err != nil {
		return err
	}

	err = producer.Enqueue(&redisqueue.Message{
		Stream: topic,
		Values: map[string]any{
			messageValuesDataKey: data,
		},
	})
	if err != nil {
		return err
	}

	return nil
}

func (messageQueue *MessageQueue) getProducerNoLock(topic string) (*redisqueue.Producer, error) {
	producer, ok := messageQueue.producerMap[topic]
	if ok {
		return producer, nil
	}

	newProducer, err := redisqueue.NewProducerWithOptions(&redisqueue.ProducerOptions{
		StreamMaxLength:      messageQueue.options.MaxLen,
		ApproximateMaxLength: true,
		RedisOptions:         messageQueue.redisOptions,
	})
	if err != nil {
		return nil, err
	}

	return newProducer, nil
}

func (messageQueue *MessageQueue) formGroupTopic(group string, topic string) string {
	return strings.Join([]string{group, topic}, "::")
}