package redis

import (
	"git.aionnect.com/aionnect/go-common/utils/logger"
	redisc "github.com/chasex/redis-go-cluster"
	"github.com/gomodule/redigo/redis"
	"github.com/spf13/viper"
	"os"
	"os/signal"
	"strings"
	"sync"
	"time"
)

type Hub struct {
	LOG     func() *logger.Logger
	pool    *redis.Pool
	cluster *redisc.Cluster
	once    sync.Once
}

func NewHub() *Hub {
	viper.SetDefault("redis.max_idle", 300)
	viper.SetDefault("redis.max_active", 1000)
	viper.SetDefault("redis.timeout", time.Duration(60000))
	return &Hub{
		LOG: func() *logger.Logger {
			return logger.New()
		},
	}
}

func (h *Hub) conn() error {
	//var err error
	maxIdle := viper.GetInt("redis.max_idle")
	maxActive := viper.GetInt("redis.max_active")
	idleTimeout := viper.GetDuration("redis.timeout")

	nodes := viper.GetStringSlice("redis.nodes")
	if nil != nodes && len(nodes) > 0 { // 集群
		//var cluster *redisc.Cluster
		cluster, err := redisc.NewCluster(&redisc.Options{
			StartNodes:   nodes,
			ConnTimeout:  5 * time.Second,
			ReadTimeout:  50 * time.Millisecond,
			WriteTimeout: 50 * time.Millisecond,
			KeepAlive:    maxActive,
			AliveTime:    idleTimeout,
		})
		if nil != err {
			return err
		}

		h.LOG().Info("Redis cluster connected")
		h.cluster = cluster
	} else { // 单点
		var pool *redis.Pool
		host := viper.GetString("redis.host")
		opts := []redis.DialOption{redis.DialConnectTimeout(5 * time.Second)}
		password := viper.GetString("redis.password")
		if len(strings.TrimSpace(password)) > 0 {
			opts = append(opts, redis.DialPassword(strings.TrimSpace(password)))
		}

		pool = &redis.Pool{
			MaxIdle:     maxIdle,
			MaxActive:   maxActive,
			IdleTimeout: idleTimeout,
			Dial: func() (redis.Conn, error) {
				if conn, err := redis.Dial("tcp", host, opts...); err != nil {
					h.LOG().Warnf("Get Redis connection failed: %s", err.Error())
					return nil, err
				} else {
					return conn, nil
				}
			},
			TestOnBorrow: func(c redis.Conn, t time.Time) error {
				_, err := c.Do("PING")
				return err
			},
		}

		// 连接测试
		conn := pool.Get()
		defer func(conn redis.Conn) {
			_ = conn.Close()
		}(conn)
		if reply, err := redis.String(conn.Do("PING")); err != nil || reply != "PONG" {

			if err != nil {
				h.LOG().Warnf("Can not connect to redis: %s", err.Error())
			} else {
				h.LOG().Warnf("Can not connect to redis: %s", reply)
			}

			return err
		}

		h.LOG().Info("Redis connected")
		h.pool = pool
	}

	go func(h2 *Hub) {
		defer func(h3 *Hub) {
			if err := h3.Close(); nil != err {
				h3.LOG().Error("Close redis connection failed:", err.Error())
			}
			h3.LOG().Info("Redis connection closed")
		}(h2)
		quit := make(chan os.Signal)
		signal.Notify(quit, os.Interrupt)
		<-quit
	}(h)
	return nil
}

func (h *Hub) Close() error {
	if nil == h {
		return nil
	}
	var err error
	if nil != h.cluster {
		h.cluster.Close()
	} else if nil != h.pool {
		err = h.pool.Close()
	}
	return err
}

func (h *Hub) Do(cmd string, args ...interface{}) (interface{}, error) {
	if nil == h {
		return nil, nil
	}
	var err error
	h.once.Do(func() {
		e := h.conn()
		if nil != e {
			err = e
		}
	})
	if nil != err {
		return nil, err
	}

	if nil != h.cluster {
		return h.cluster.Do(cmd, args...)
	} else if nil != h.pool {
		conn := h.pool.Get()
		defer func(conn redis.Conn) {
			_ = conn.Close()
		}(conn)
		do, err := conn.Do(cmd, args...)
		if nil != err {
			return nil, err
		}
		return do, nil
	} else {
		return nil, ErrRedisConnNil
	}
}

const (
	ErrRedisConnNil = ErrRedis("redis conn nil")
)

type ErrRedis string

func (err ErrRedis) Error() string {
	return string(err)
}

func (h *Hub) Get() (redis.Conn, error) {
	if nil == h.pool {
		err := h.conn()
		if nil != err {
			return nil, err
		}
	}
	conn := h.pool.Get()
	return conn, nil
}