package nsqclient

import (
	"fmt"
	"time"

	nsq "github.com/nsqio/go-nsq"
)

type Producer interface {
	Publish(topic string, body []byte) error
	MultiPublish(topic string, body [][]byte) error
	DeferredPublish(topic string, delay time.Duration, body []byte) error
}

var _ Producer = (*producer)(nil)

type producer struct {
	pool Pool
}

var (
	// 				   name   pool producer
	nsqList = make(map[string]Pool)
)

type Config struct {
	Addr     string `toml:"addr" json:"addr"`
	InitSize int    `toml:"init_size" json:"init_size"`
	MaxSize  int    `toml:"max_size" json:"max_size"`
}

func CreateProducerPool(configs map[string]Config) {
	for name, conf := range configs {
		n, err := newProducerPool(conf.Addr, conf.InitSize, conf.MaxSize)
		if err == nil {
			nsqList[name] = n
			// 支持ip:port寻址
			nsqList[conf.Addr] = n
		}
	}
}

func DestroyProducerPool() {
	for _, p := range nsqList {
		p.Close()
	}
}

func GetProducer(key ...string) (*producer, error) {
	k := "default"
	if len(key) > 0 {
		k = key[0]
	}
	if n, ok := nsqList[k]; ok {
		return &producer{n}, nil
	}
	return nil, fmt.Errorf("GetProducer can't get producer")
}

// CreateNSQProducer create nsq producer
func newProducer(addr string, options ...func(*nsq.Config)) (*nsq.Producer, error) {
	cfg := nsq.NewConfig()
	for _, option := range options {
		option(cfg)
	}

	producer, err := nsq.NewProducer(addr, cfg)
	if err != nil {
		return nil, err
	}
	// producer.SetLogger(log.New(os.Stderr, "", log.Flags()), nsq.LogLevelError)
	return producer, nil
}

// CreateNSQProducerPool create a nwq producer pool
func newProducerPool(addr string, initSize, maxSize int, options ...func(*nsq.Config)) (Pool, error) {
	factory := func() (*nsq.Producer, error) {
		// TODO 这里应该执行ping方法来确定连接是正常的否则不应该创建conn
		return newProducer(addr, options...)
	}
	nsqPool, err := NewChannelPool(initSize, maxSize, factory)
	if err != nil {
		return nil, err
	}
	return nsqPool, nil
}

func NewProducer(addr string) (*producer, error) {
	CreateProducerPool(map[string]Config{"default": {addr, 1, 1}})
	return GetProducer()
}

func retry(num int, fn func() error) error {
	var err error
	for i := 0; i < num; i++ {
		err = fn()
		if err == nil {
			break
		}
	}
	return err
}

func (p *producer) Publish(topic string, body []byte) error {
	nsq, err := p.pool.Get()
	if err != nil {
		return err
	}
	defer nsq.Close()

	return retry(2, func() error {
		return nsq.Publish(topic, body)
	})
}

func (p *producer) MultiPublish(topic string, body [][]byte) error {
	nsq, err := p.pool.Get()
	if err != nil {
		return err
	}
	defer nsq.Close()

	return retry(2, func() error {
		return nsq.MultiPublish(topic, body)
	})
}

func (p *producer) DeferredPublish(topic string, delay time.Duration, body []byte) error {
	nsq, err := p.pool.Get()
	if err != nil {
		return err
	}
	defer nsq.Close()

	return retry(2, func() error {
		return nsq.DeferredPublish(topic, delay, body)
	})
}