package redis

import (
	"context"
	"time"

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

type RedisLock struct {
	conn    redis.Cmdable
	timeout time.Duration
	key     string
	val     string
}

var ctx = context.Background()

func NewRedisLock(conn redis.Cmdable, key, val string, timeout time.Duration) *RedisLock {
	return &RedisLock{conn: conn, timeout: timeout, key: key, val: val}
}

// TryLock return true ===> Get the lock successfully
func (lock *RedisLock) TryLock() (bool, error) {
	return lock.conn.SetNX(ctx, lock.key, lock.val, lock.timeout).Result()
}

func (lock *RedisLock) UnLock() error {
	luaDel := redis.NewScript("if redis.call('get',KEYS[1]) == ARGV[1] then " +
		"return redis.call('del',KEYS[1]) else return 0 end")
	return luaDel.Run(ctx, lock.conn, []string{lock.key}, lock.val).Err()
}

func (lock *RedisLock) GetLockKey() string {
	return lock.key
}

func (lock *RedisLock) GetLockVal() string {
	return lock.val
}