package ru.smoltelecom.zapret.protocol;

import java.io.BufferedReader;
import java.io.InputStreamReader;

import ru.smoltelecom.zapret.protocol.auth.UserPassInfo;

import com.jcraft.jsch.Channel;
import com.jcraft.jsch.ChannelExec;
import com.jcraft.jsch.ChannelSftp;
import com.jcraft.jsch.ChannelShell;
import com.jcraft.jsch.JSch;
import com.jcraft.jsch.Session;
import com.jcraft.jsch.UserInfo;

import expect4j.Expect4j;

public class SFTP {

    private String host;
    private String userName;
    private String userPassword;
    private int port;

    private Session session;
    private Channel channel;

    private ChannelShell shell;
    private Expect4j     expect;
    private ExpectHelper expectHelper;

    private JSch jsch;

    public SFTP(String host, String userName, String userPassword, int port) {
        this.host = host;
        this.userName = userName;
        this.userPassword = userPassword;
        this.port = port;
    }

    public void open() throws Exception {
        jsch = new JSch();
        session = jsch.getSession(userName, host, port);
        UserInfo ui = new UserPassInfo(userPassword);
        session.setUserInfo(ui);
        session.connect();
    }

    public ChannelSftp openSFTPChannel() throws Exception {
        channel = session.openChannel("sftp");
        channel.connect();
        return (ChannelSftp)channel;
    }

    public ExpectHelper getExpect(String rootPassword) throws Exception {

        if(shell==null){
            shell  = (ChannelShell)session.openChannel("shell");
            expect = new Expect4j(shell.getInputStream(),shell.getOutputStream());
            expect.setDefaultTimeout(1000L);
            expectHelper = new ExpectHelper(expect,rootPassword);
        }

        return expectHelper;
    }

    public void closeExpect(){
        shell.disconnect();
        expect.close();
    }

    public String execCommand(String command) throws Exception {

        Channel     channel = session.openChannel("exec");
        ChannelExec exec    = (ChannelExec)channel;

        BufferedReader in = new BufferedReader(new InputStreamReader(exec.getInputStream()));
        exec.setCommand(command);
        exec.connect();

        String msg = null;
        String result = "";

            while ((msg = in.readLine()) != null) {
                result+=msg+"\n";
                System.out.print(msg+"\n");
            }

        exec.disconnect();

        return result;

    }

    public void close(){

        if (channel != null) {
            channel.disconnect();
        }
        if (session != null) {
            session.disconnect();
        }

    }

}