package application

import (
	"context"
	"fmt"
	"mayfly-go/internal/constant"
	machineapp "mayfly-go/internal/machine/application"
	"mayfly-go/internal/machine/infrastructure/machine"
	"mayfly-go/internal/redis/domain/entity"
	"mayfly-go/internal/redis/domain/repository"
	"mayfly-go/pkg/biz"
	"mayfly-go/pkg/cache"
	"mayfly-go/pkg/global"
	"mayfly-go/pkg/model"
	"mayfly-go/pkg/utils"
	"net"
	"strconv"
	"strings"
	"time"

	"github.com/redis/go-redis/v9"
)

type Redis interface {
	// 分页获取机器脚本信息列表
	GetPageList(condition *entity.RedisQuery, pageParam *model.PageParam, toEntity any, orderBy ...string) *model.PageResult[any]

	Count(condition *entity.RedisQuery) int64

	// 根据id获取
	GetById(id uint64, cols ...string) *entity.Redis

	// 根据条件获取
	GetRedisBy(condition *entity.Redis, cols ...string) error

	Save(entity *entity.Redis)

	// 删除数据库信息
	Delete(id uint64)

	// 获取数据库连接实例
	// id: 数据库实例id
	// db: 库号
	GetRedisInstance(id uint64, db int) *RedisInstance
}

func newRedisApp(redisRepo repository.Redis) Redis {
	return &redisAppImpl{
		redisRepo: redisRepo,
	}
}

type redisAppImpl struct {
	redisRepo repository.Redis
}

// 分页获取机器脚本信息列表
func (r *redisAppImpl) GetPageList(condition *entity.RedisQuery, pageParam *model.PageParam, toEntity any, orderBy ...string) *model.PageResult[any] {
	return r.redisRepo.GetRedisList(condition, pageParam, toEntity, orderBy...)
}

func (r *redisAppImpl) Count(condition *entity.RedisQuery) int64 {
	return r.redisRepo.Count(condition)
}

// 根据id获取
func (r *redisAppImpl) GetById(id uint64, cols ...string) *entity.Redis {
	return r.redisRepo.GetById(id, cols...)
}

// 根据条件获取
func (r *redisAppImpl) GetRedisBy(condition *entity.Redis, cols ...string) error {
	return r.redisRepo.GetRedis(condition, cols...)
}

func (r *redisAppImpl) Save(re *entity.Redis) {
	// ’修改信息且密码不为空‘ or ‘新增’需要测试是否可连接
	if (re.Id != 0 && re.Password != "") || re.Id == 0 {
		TestRedisConnection(re)
	}

	// 查找是否存在该库
	oldRedis := &entity.Redis{Host: re.Host}
	if re.SshTunnelMachineId > 0 {
		oldRedis.SshTunnelMachineId = re.SshTunnelMachineId
	}
	err := r.GetRedisBy(oldRedis)

	if re.Id == 0 {
		biz.IsTrue(err != nil, "该实例已存在")
		re.PwdEncrypt()
		r.redisRepo.Insert(re)
	} else {
		// 如果存在该库，则校验修改的库是否为该库
		if err == nil {
			biz.IsTrue(oldRedis.Id == re.Id, "该实例已存在")
		}
		// 如果修改了redis实例的库信息，则关闭旧库的连接
		if oldRedis.Db != re.Db || oldRedis.SshTunnelMachineId != re.SshTunnelMachineId {
			for _, dbStr := range strings.Split(oldRedis.Db, ",") {
				db, _ := strconv.Atoi(dbStr)
				CloseRedis(re.Id, db)
			}
		}
		re.PwdEncrypt()
		r.redisRepo.Update(re)
	}
}

// 删除Redis信息
func (r *redisAppImpl) Delete(id uint64) {
	re := r.GetById(id)
	biz.NotNil(re, "该redis信息不存在")
	// 如果存在连接，则关闭所有库连接信息
	for _, dbStr := range strings.Split(re.Db, ",") {
		db, _ := strconv.Atoi(dbStr)
		CloseRedis(re.Id, db)
	}
	r.redisRepo.Delete(id)
}

// 获取数据库连接实例
func (r *redisAppImpl) GetRedisInstance(id uint64, db int) *RedisInstance {
	// Id不为0，则为需要缓存
	needCache := id != 0
	if needCache {
		load, ok := redisCache.Get(getRedisCacheKey(id, db))
		if ok {
			return load.(*RedisInstance)
		}
	}
	// 缓存不存在，则回调获取redis信息
	re := r.GetById(id)
	re.PwdDecrypt()
	biz.NotNil(re, "redis信息不存在")

	redisMode := re.Mode
	var ri *RedisInstance
	if redisMode == "" || redisMode == entity.RedisModeStandalone {
		ri = getRedisCient(re, db)
		// 测试连接
		_, e := ri.Cli.Ping(context.Background()).Result()
		if e != nil {
			ri.Close()
			panic(biz.NewBizErr(fmt.Sprintf("redis连接失败: %s", e.Error())))
		}
	} else if redisMode == entity.RedisModeCluster {
		ri = getRedisClusterClient(re)
		// 测试连接
		_, e := ri.ClusterCli.Ping(context.Background()).Result()
		if e != nil {
			ri.Close()
			panic(biz.NewBizErr(fmt.Sprintf("redis集群连接失败: %s", e.Error())))
		}
	} else if redisMode == entity.RedisModeSentinel {
		ri = getRedisSentinelCient(re, db)
		// 测试连接
		_, e := ri.Cli.Ping(context.Background()).Result()
		if e != nil {
			ri.Close()
			panic(biz.NewBizErr(fmt.Sprintf("redis sentinel连接失败: %s", e.Error())))
		}
	}

	global.Log.Infof("连接redis: %s", re.Host)
	if needCache {
		redisCache.Put(getRedisCacheKey(id, db), ri)
	}
	return ri
}

// 生成redis连接缓存key
func getRedisCacheKey(id uint64, db int) string {
	return fmt.Sprintf("%d/%d", id, db)
}

func toRedisInfo(re *entity.Redis, db int) *RedisInfo {
	redisInfo := new(RedisInfo)
	utils.Copy(redisInfo, re)
	redisInfo.Db = db
	return redisInfo
}

func getRedisCient(re *entity.Redis, db int) *RedisInstance {
	ri := &RedisInstance{Id: getRedisCacheKey(re.Id, db), Info: toRedisInfo(re, db)}

	redisOptions := &redis.Options{
		Addr:         re.Host,
		Password:     re.Password, // no password set
		DB:           db,          // use default DB
		DialTimeout:  8 * time.Second,
		ReadTimeout:  -1, // Disable timeouts, because SSH does not support deadlines.
		WriteTimeout: -1,
	}
	if re.SshTunnelMachineId > 0 {
		redisOptions.Dialer = getRedisDialer(re.SshTunnelMachineId)
	}
	ri.Cli = redis.NewClient(redisOptions)
	return ri
}

func getRedisClusterClient(re *entity.Redis) *RedisInstance {
	ri := &RedisInstance{Id: getRedisCacheKey(re.Id, 0), Info: toRedisInfo(re, 0)}

	redisClusterOptions := &redis.ClusterOptions{
		Addrs:       strings.Split(re.Host, ","),
		Password:    re.Password,
		DialTimeout: 8 * time.Second,
	}
	if re.SshTunnelMachineId > 0 {
		redisClusterOptions.Dialer = getRedisDialer(re.SshTunnelMachineId)
	}
	ri.ClusterCli = redis.NewClusterClient(redisClusterOptions)
	return ri
}

func getRedisSentinelCient(re *entity.Redis, db int) *RedisInstance {
	ri := &RedisInstance{Id: getRedisCacheKey(re.Id, db), Info: toRedisInfo(re, db)}
	// sentinel模式host为 masterName=host:port,host:port
	masterNameAndHosts := strings.Split(re.Host, "=")
	sentinelOptions := &redis.FailoverOptions{
		MasterName:       masterNameAndHosts[0],
		SentinelAddrs:    strings.Split(masterNameAndHosts[1], ","),
		Password:         re.Password, // no password set
		SentinelPassword: re.Password, // 哨兵节点密码需与redis节点密码一致
		DB:               db,          // use default DB
		DialTimeout:      8 * time.Second,
		ReadTimeout:      -1, // Disable timeouts, because SSH does not support deadlines.
		WriteTimeout:     -1,
	}
	if re.SshTunnelMachineId > 0 {
		sentinelOptions.Dialer = getRedisDialer(re.SshTunnelMachineId)
	}
	ri.Cli = redis.NewFailoverClient(sentinelOptions)
	return ri
}

func getRedisDialer(machineId int) func(ctx context.Context, network, addr string) (net.Conn, error) {
	sshTunnel := machineapp.GetMachineApp().GetSshTunnelMachine(machineId)
	return func(_ context.Context, network, addr string) (net.Conn, error) {
		if sshConn, err := sshTunnel.GetDialConn(network, addr); err == nil {
			// 将ssh conn包装，否则redis内部设置超时会报错,ssh conn不支持设置超时会返回错误: ssh: tcpChan: deadline not supported
			return &utils.WrapSshConn{Conn: sshConn}, nil
		} else {
			return nil, err
		}
	}
}

//------------------------------------------------------------------------------

// redis客户端连接缓存，指定时间内没有访问则会被关闭
var redisCache = cache.NewTimedCache(constant.RedisConnExpireTime, 5*time.Second).
	WithUpdateAccessTime(true).
	OnEvicted(func(key any, value any) {
		global.Log.Info(fmt.Sprintf("删除redis连接缓存 id = %s", key))
		value.(*RedisInstance).Close()
	})

// 移除redis连接缓存并关闭redis连接
func CloseRedis(id uint64, db int) {
	redisCache.Delete(getRedisCacheKey(id, db))
}

func init() {
	machine.AddCheckSshTunnelMachineUseFunc(func(machineId int) bool {
		// 遍历所有redis连接实例，若存在redis实例使用该ssh隧道机器，则返回true，表示还在使用中...
		items := redisCache.Items()
		for _, v := range items {
			if v.Value.(*RedisInstance).Info.SshTunnelMachineId == machineId {
				return true
			}
		}
		return false
	})
}

func TestRedisConnection(re *entity.Redis) {
	var cmd redis.Cmdable
	// 取第一个库测试连接即可
	dbStr := strings.Split(re.Db, ",")[0]
	db, _ := strconv.Atoi(dbStr)
	if re.Mode == "" || re.Mode == entity.RedisModeStandalone {
		rcli := getRedisCient(re, db)
		defer rcli.Close()
		cmd = rcli.Cli
	} else if re.Mode == entity.RedisModeCluster {
		ccli := getRedisClusterClient(re)
		defer ccli.Close()
		cmd = ccli.ClusterCli
	} else if re.Mode == entity.RedisModeSentinel {
		rcli := getRedisSentinelCient(re, db)
		defer rcli.Close()
		cmd = rcli.Cli
	}

	// 测试连接
	_, e := cmd.Ping(context.Background()).Result()
	biz.ErrIsNilAppendErr(e, "Redis连接失败: %s")
}

type RedisInfo struct {
	Id      uint64
	Host    string
	Db      int // 库号
	TagPath string
	Mode    string
	Name    string

	SshTunnelMachineId int
}

// 获取记录日志的描述
func (r *RedisInfo) GetLogDesc() string {
	return fmt.Sprintf("Redis[id=%d, tag=%s, host=%s, db=%d]", r.Id, r.TagPath, r.Host, r.Db)
}

// redis实例
type RedisInstance struct {
	Id   string
	Info *RedisInfo

	Cli        *redis.Client
	ClusterCli *redis.ClusterClient
}

// 获取命令执行接口的具体实现
func (r *RedisInstance) GetCmdable() redis.Cmdable {
	redisMode := r.Info.Mode
	if redisMode == "" || redisMode == entity.RedisModeStandalone || r.Info.Mode == entity.RedisModeSentinel {
		return r.Cli
	}
	if redisMode == entity.RedisModeCluster {
		return r.ClusterCli
	}
	return nil
}

func (r *RedisInstance) Scan(cursor uint64, match string, count int64) ([]string, uint64) {
	keys, newcursor, err := r.GetCmdable().Scan(context.Background(), cursor, match, count).Result()
	biz.ErrIsNilAppendErr(err, "scan失败: %s")
	return keys, newcursor
}

func (r *RedisInstance) Close() {
	mode := r.Info.Mode
	if mode == entity.RedisModeStandalone || mode == entity.RedisModeSentinel {
		if err := r.Cli.Close(); err != nil {
			global.Log.Errorf("关闭redis单机实例[%s]连接失败: %s", r.Id, err.Error())
		}
		r.Cli = nil
	}
	if mode == entity.RedisModeCluster {
		if err := r.ClusterCli.Close(); err != nil {
			global.Log.Errorf("关闭redis集群实例[%s]连接失败: %s", r.Id, err.Error())
		}
		r.ClusterCli = nil
	}
}