package com.mikroTik.wiki;

// *** Based on Sources from the MikroTik wiki - Free to use license
// *** Orig author apparently "janisk"

/*
 * This contains connection. Everything should be here,
 * should operate with this class only
 */
import java.io.*;
import java.net.*;
import java.security.KeyManagementException;
import java.security.NoSuchAlgorithmException;
import java.security.cert.X509Certificate;
import java.util.concurrent.LinkedBlockingQueue;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.net.ssl.SSLContext;
import javax.net.ssl.SSLSocket;
import javax.net.ssl.SSLSocketFactory;
import javax.net.ssl.TrustManager;
import javax.net.ssl.X509TrustManager;

/**
 *
 * @author janisk
 */
public class ApiConn extends Thread {

    private Socket sock = null;
    private DataOutputStream out = null;
    private DataInputStream in = null;
    private String ipAddress;
    private int ipPort;
    private boolean connected = false;
    private String message = "Not connected";
    private ReadCommand readCommand = null;
    private WriteCommand writeCommand = null;
    private Thread listener = null;
    LinkedBlockingQueue queue = new LinkedBlockingQueue(40);
    private SSLMode sslMode;

    public enum SSLMode {

        /**
         * No encryption
         */
        None,
        /**
         * SSL without certificate check
         */
        Weak,
        /**
         * SSL verifiying for valid certificate
         */
        Strict
    }

    /**
     * Constructor of the connection class
     *
     * @param ipAddress - IP address of the router you want to conenct to
     * @param ipPort - port used for connection, ROS default is 8728
     */
    public ApiConn(String ipAddress, int ipPort, SSLMode sslMode) {
        this.sslMode = sslMode;
        this.ipAddress = ipAddress;
        this.ipPort = ipPort;
        this.setName("settings");
    }

    /**
     * State of connection
     *
     * @return - if connection is established to router it returns true.
     */
    public boolean isConnected() {
        return connected;
    }

    public void disconnect() throws IOException {
        listener.interrupt();
        sock.close();
    }

    private void listen() {
        if (this.isConnected()) {
            if (readCommand == null) {
                readCommand = new ReadCommand(in, queue);
            }
            listener = new Thread(readCommand);
            listener.setDaemon(true);
            listener.setName("listener");
            listener.start();

        }
    }

    /**
     * to get IP address of the connection. Reads data from socket created.
     *
     * @return InetAddress
     */
    public InetAddress getIpAddress() {
        return sock == null ? null : sock.getInetAddress();
    }

    /**
     * returns ip address that socket is asociated with.
     *
     * @return InetAddress
     */
    public InetAddress getLocalIpAddress() {
        return sock == null ? null : sock.getLocalAddress();
    }

    /**
     * Socket remote port number
     *
     * @return
     */
    public int getPort() {
        return sock == null ? null : sock.getPort();
    }

    /**
     * return local prot used by socket
     *
     * @return
     */
    public int getLocalPort() {
        return sock == null ? null : sock.getLocalPort();
    }

    /**
     * Returns status message set up bu class.
     *
     * @return
     */
    public String getMessage() {
        return message;
    }

    /**
     * sets and exectues command (sends it to RouterOS host connected)
     *
     * @param s - command will be sent to RouterOS for example
     * "/ip/address/print\n=follow="
     * @return
     */
    public String sendCommand(String s) {
        return writeCommand.setCommand(s).runCommand();
    }

    /**
     * exeecutes already set command.
     *
     * @return returns status of the command sent
     */
    public String runCommand() {
        return writeCommand.runCommand();
    }

    /**
     * Tries to fech data that is repllied to commands sent. It will wait till
     * it can return something.
     *
     * @return returns data sent by RouterOS
     * @throws java.lang.InterruptedException
     */
    public String getData() throws InterruptedException {
        String s = (String) queue.take();
        return s;
    }

    /**
     * returns command that is set at this moment. And will be exectued if
     * runCommand is exectued.
     *
     * @return
     */
    public String getCommand() {
        return writeCommand.getCommand();
    }

    /**
     * set up method that will log you in
     *
     * @param name - username of the user on the router
     * @param password - password for the user
     * @return
     */
    public String login(String name, char[] password) {
        this.sendCommand("/login");
        String s = "a";
        try {
            s = this.getData();
        } catch (InterruptedException ex) {
            Logger.getLogger(ApiConn.class.getName()).log(Level.SEVERE, null, ex);
            return "failed read #1";
        }
        if (!s.contains("!trap") && s.length() > 4) {
            String[] tmp = s.trim().split("\n");
            if (tmp.length > 1) {
                tmp = tmp[1].split("=ret=");
                s = "";
                String transition = tmp[tmp.length - 1];
                String chal = "";
                chal = Hasher.hexStrToStr("00") + new String(password) + Hasher.hexStrToStr(transition);
                chal = Hasher.hashMD5(chal);
                String m = "/login\n=name=" + name + "\n=response=00" + chal;
                s = this.sendCommand(m);
                try {
                    s = this.getData();
                } catch (InterruptedException ex) {
                    Logger.getLogger(ApiConn.class.getName()).log(Level.SEVERE, null, ex);
                    return "failed read #2";
                }
                if (s.contains("!done")) {
                    if (!s.contains("!trap")) {
                        return "Login successful";
                    }
                }
            }
        }
        return "Login failed";
    }

    private static final TrustManager[] ALL_TRUSTING_TRUST_MANAGER = new TrustManager[]{
        new X509TrustManager() {
            public X509Certificate[] getAcceptedIssuers() {
                return null;
            }

            public void checkClientTrusted(X509Certificate[] certs, String authType) {
            }

            public void checkServerTrusted(X509Certificate[] certs, String authType) {
            }
        }
    };

//    private static final HostnameVerifier ALL_TRUSTING_HOSTNAME_VERIFIER = new HostnameVerifier() {
//        public boolean verify(String hostname, SSLSession session) {
//            return true;
//        }
//    };
    @Override
    public void run() {
        try {
            InetAddress ia = InetAddress.getByName(ipAddress);
            if (ia.isReachable(1000)) {

                SSLSocketFactory sslSockFact = null;
                if (sslMode == SSLMode.None) {
                    sock = new Socket(ipAddress, ipPort);
                } else if (sslMode == SSLMode.Weak) {
                    try {
                        SSLContext sc = SSLContext.getInstance("SSL");
                        sc.init(null, ALL_TRUSTING_TRUST_MANAGER, new java.security.SecureRandom());
                        sslSockFact = sc.getSocketFactory();
                    } catch (NoSuchAlgorithmException | KeyManagementException nex) {
                        throw new RuntimeException(nex);
                    }
                } else {// if (sslMode == SSLMode.Strict) {
                    sslSockFact = (SSLSocketFactory) SSLSocketFactory.getDefault();

                }
                if (sslSockFact != null) {
                    SSLSocket socket = (SSLSocket) sslSockFact.createSocket(ipAddress, ipPort);
                    sock = socket;
                }

                //sock = new Socket(ipAddress, ipPort);
                in = new DataInputStream(sock.getInputStream());
                out = new DataOutputStream(sock.getOutputStream());
                connected = true;
                readCommand = new ReadCommand(in, queue);
                writeCommand = new WriteCommand(out);
                this.listen();
                message = "Connected";
            } else {
                message = "Not reachable";
            }
        } catch (UnknownHostException ex) {
            connected = false;
            message = ex.getMessage();
            ex.printStackTrace();
        } catch (IOException ex) {
            connected = false;
            message = ex.getMessage();
            ex.printStackTrace();
        }
    }
}