无可用代理后报错

[zj-xjy]

已无可用代理，请重新运行程序
可用代理已仅剩0个,[]，
panic: runtime error: index out of range [0] with length 0

goroutine 6179 [running]:
Deadpool/utils.getNextProxy()
Deadpool/utils/utils.go:247 +0x1c5
Deadpool/utils.transmitReqFromClient({0xd8f3f6, 0x3}, {0xc000494060, 0x11})
Deadpool/utils/utils.go:218 +0x37
Deadpool/utils.transmitReqFromClient({0xd8f3f6, 0x3}, {0xc000494060, 0x11})
Deadpool/utils/utils.go:232 +0x1d0
Deadpool/utils.DefineDial({0xc0002e61a0?, 0x10?}, {0xd8f3f6?, 0x4?}, {0xc000494060?, 0x1bb?})
Deadpool/utils/utils.go:214 +0x29
github.com/armon/go-socks5.(*Server).handleConnect(0xc000620ac0, {0xe1d200?, 0x103c700?}, {0x110e233ef28, 0xc00051c000}, 0xc0001c6040)
github.com/armon/go-socks5@v0.0.0-20160902184237-e75332964ef5/request.go:177 +0x175
github.com/armon/go-socks5.(*Server).handleRequest(0xc000620ac0, 0xc0001c6040, {0x110e233ef28, 0xc00051c000})
github.com/armon/go-socks5@v0.0.0-20160902184237-e75332964ef5/request.go:145 +0x205
github.com/armon/go-socks5.(*Server).ServeConn(0xc000620ac0, {0xe1e7e8, 0xc00051c000})
github.com/armon/go-socks5@v0.0.0-20160902184237-e75332964ef5/socks5.go:162 +0x7c7
created by github.com/armon/go-socks5.(*Server).Serve in goroutine 1
github.com/armon/go-socks5@v0.0.0-20160902184237-e75332964ef5/socks5.go:115 +0x39

是因为改了后面的代码没循环使用代理池的代理吗？每个代理只使用了一次。
希望能添加功能：可以使用命令指定一个ip进行代理，或者等到ip被ban后切换ip
版本：最新1.5， 实测1.3版本没这个问题