package xenserver

import (
	"fmt"
	"github.com/mitchellh/multistep"
	"github.com/mitchellh/packer/packer"
	"log"
	"net"
)

type stepForwardPortOverSSH struct {
	RemotePort func(state multistep.StateBag) (uint, error)
	RemoteDest func(state multistep.StateBag) (string, error)

	HostPortMin uint
	HostPortMax uint

	ResultKey string
}

func (self *stepForwardPortOverSSH) Run(state multistep.StateBag) multistep.StepAction {

	config := state.Get("config").(config)
	ui := state.Get("ui").(packer.Ui)

	// Find a free local port:

	log.Printf("Looking for an available port between %d and %d",
		self.HostPortMin,
		self.HostPortMax)

	var sshHostPort uint
	var foundPort bool

	foundPort = false

	for i := self.HostPortMin; i < self.HostPortMax; i++ {
		sshHostPort = i
		log.Printf("Trying port: %d", sshHostPort)
		l, err := net.Listen("tcp", fmt.Sprintf("127.0.0.1:%d", sshHostPort))
		if err == nil {
			l.Close()
			foundPort = true
			break
		}

	}

	if !foundPort {
		log.Fatal("Error: unable to find free host port. Try providing a larger range")
		return multistep.ActionHalt
	}

	ui.Say(fmt.Sprintf("Creating a local port forward over SSH on local port %d", sshHostPort))

	remotePort, _ := self.RemotePort(state)
	remoteDest, _ := self.RemoteDest(state)

	go ssh_port_forward(sshHostPort, remotePort, remoteDest, config.HostIp, config.Username, config.Password)
	ui.Say(fmt.Sprintf("Port forward setup. %d ---> %s:%d on %s", sshHostPort, remoteDest, remotePort, config.HostIp))

	// Provide the local port to future steps.
	state.Put(self.ResultKey, sshHostPort)

	return multistep.ActionContinue
}

func (self *stepForwardPortOverSSH) Cleanup(state multistep.StateBag) {}