package frp

import (
    "github.com/fatedier/frp/pkg/config"
    "github.com/fatedier/frp/server"
    "github.com/phayes/freeport"
    "io/ioutil"
    "net/http"
)

type Server struct {
    address string
    port    int
}

// StartFRPProxyFromRandom starts
// reverse proxy server based on
// a random port generated
func StartFRPProxyFromRandom() (int, error) {
    // gets current configuration
    //config, err := configP2PRC.ConfigInit()
    //if err != nil {
    //    return err
    //}

    var s Server
    s.address = "0.0.0.0"

    // use random port
    OpenPorts, err := freeport.GetFreePorts(1)
    if err != nil {
        return 0, err
    }

    s.port = OpenPorts[0]

    // start FRP server

    go s.StartFRPServer()

    return OpenPorts[0], nil

}

// StartFRPServer The initial plan is only support reverse proxy
// for TCP ports
// This function starts a server that can act as a reverse
// proxy for nodes behind NAT.
func (s *Server) StartFRPServer() error {
    baseConfig := config.GetDefaultServerConf()
    baseConfig.BindAddr = s.address

    baseConfig.BindPort = s.port
    service, err := server.NewService(baseConfig)
    if err != nil {
        return err
    }

    service.Run()
    return nil
}

// GetFRPServerPort Gets the port no from the FRPServer to establish
// the FRP connection needed.
func GetFRPServerPort(host string) (string, error) {
    resp, err := http.Get(host + "/FRPPort")

    if err != nil {
        return "", err
    }

    defer resp.Body.Close()

    body, err := ioutil.ReadAll(resp.Body)

    if err != nil {
        return "", err
    }

    return string(body), nil
}