package umich.cbe.distview.demos;

import java.lang.*;
import java.util.*;
import java.io.*;

import umich.cbe.distview.io.*;
import umich.cbe.distview.server.*;
import umich.cbe.distview.util.DVApplet;

/**
 * A TestClient is a simple client which connects to the server, joins a 
 * group, sends/receives broadcast messages and measures roundtrip delays
 * for these messages.
 * Alternatively, a TestClient can be used to cause the server print status
 * information.
 */
public class TestClient extends DVApplet {
  DVSharedState	myGroup;

  //for testing
  //public long t2, t3, t4, t5, t6;
  Thread senderThread;
  long tstart[], tstop[], t0, t1, total=0;
  int t[], cnt=0, no=0;


  public TestClient(String hostName, int portNumber, String grpName) {
    serverHostName = hostName;
    serverPort = portNumber;
    appletGroupName = grpName;
    userName = "TestClient";
    //userName = "Snooper";
  }


  /**
   * Starts a session. Joins a collaboration group.
   */
  public void startSession() {
    int ret = 0;
    stateSize = 0;

    if (group == null)
      getGroup();  // this sets group if possible

    // join the collaboration group if needed
    if (group != null) {
      prepareToJoin(group);
      ret = group.join(false, stateSize);
      if (ret == 0) {
	group.disconnect();
	group = null;
      }
      else {
	joined(group);
      }
    }
  }


  /**
   * Performs application-specific operations, e.g., set a bcast handler
   * and add a shared object before joining.
   */
  public void prepareToJoin(DVSharedState group) {
    TCBcastHandler cHandler = new TCBcastHandler(this);
    CBEDebug.debug("prepareToJoin called");
    group.setBcastHandler(cHandler);
    myGroup = group;
  }


  /**
   * Notifies that this applet has successfully joined the specified group.
   */
  public void joined(DVSharedState group) {
    group.setGroupProperty(DVGroupProperty.GROUP_TYPE, "Chat");
  }


  public void hideApplet() {}


  public void killApplet() {
    stopSession();
  }


  /**
   * Creates a new TestClient.
   * @param args[]  port#  hostname
   */
  public static void main(String args[]) {
    String grpname, grptype;
    int port, delay = 0;
    String host;

    // to be used with serverInfo()
    /*
    if(args.length < 2){
      System.out.println("Usage : TestClient [port#] [hostname]");
      System.exit(0);
    }
    grpname = new String("Snooper");
     try {
      port = Integer.parseInt(args[0],10);
    }
    catch(Exception e) {
      System.out.println("Defaulting to port 12345");
      port = 12345;
    }
    host = args[1];
    */

    // to be used with action()
    if(args.length < 3){
      System.out.println("Usage : TestClient [Group_name] [port#] [hostname]");
      System.exit(0);
    }
    grpname = args[0];
    try {
      port = Integer.parseInt(args[1],10);
    }
    catch(Exception e) {
      System.out.println("Defaulting to port 12345");
      port = 12345;
    }
    host = args[2];

    TestClient TC = new TestClient(host, port, grpname);
    CBEDebug.setLevel(0);
    TC.startSession();
    /* use either serverInfo() or action(), but not both
     * serverInfo() causes the server to print server information
     * action() sends broadcast messages and measures the roundtrip delay
     */
    //TC.serverInfo();
    TC.action();
  }
  

  /**
   * Sends SERVER_INFO messages to the sever, causing the server to display
   * status information.
   */
  private void serverInfo() {
    int i=0, size = 0;
    String command = null;
    size = myGroup.getGroupSize();
    System.out.println("GROUP SIZE = " + size);
    BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
    while(true) {
      System.out.print("\nPrint server info ? (y/n):  ");
      System.out.flush();
      try {
	command = br.readLine();
      }
      catch(Exception e) {
	System.out.println("input read error");
	System.exit(0);
      }
      if(!command.equals("y")) {
	stopSession();
	System.exit(0);
      }
      myGroup.serverInfo();
    }
  }


  /**
   * Sends a String message. 
   * @param aMsg  the message
   */
  public void sendMsg(String aMsg)    {
    if (myGroup != null) {
      try {
	Message msg = new Message(Message.GROUP_MESSAGE, Message.STRING);
	msg.setMsgData(aMsg);
	//t2 = System.currentTimeMillis();
	myGroup.bcast(msg);
	//t3 = System.currentTimeMillis();
      }
      catch(Exception e) {
	System.out.println("TestClient: exception in newMsg(): "+
			   e.getMessage());
      }
    }
  }


  /**
   * Sends a byte array message. 
   * @param aMsg  the message
   */
  public void sendMsg(byte aMsg[]) {
    if (myGroup != null) {
      try {
	Message msg = new Message(Message.GROUP_MESSAGE, Message.B_ARRAY);
	msg.setMsgBuf(aMsg, aMsg.length);
	//t2 = System.currentTimeMillis();
	myGroup.bcast(msg);
	//t3 = System.currentTimeMillis();
      }
      catch(Exception e) {
	System.out.println("TestClient: exception in newMsg(): "+
			   e.getMessage());
      }
    }
  }


  /**
   * Sends broadcast messages in a loop and measures the roundtrip delay for
   * these messages. 
   */
  private void action() {
    int size=0, delay=0, i;
    size = myGroup.getGroupSize();
    System.out.println("GROUP SIZE = " + size);
    // the next line is optional
    myGroup.serverInfo();

    senderThread = Thread.currentThread();
    senderThread.setPriority(2);
    BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
    DataInputStream in = new DataInputStream(System.in);
    while(true) {
      System.out.print("\nSize of the messages to send(chars): ");
      System.out.flush();
      try {
	size = Integer.parseInt(br.readLine());
      }
      catch(Exception e) {
	System.out.println("Number format error");
	System.exit(0);
      }
      if(size <= 0) {
	stopSession();
	System.exit(0);
      }

      byte sbuf[] = new byte[size];
      System.out.print("Number   of   messages   to  send  : ");
      System.out.flush();
      try {
	no = Integer.parseInt(br.readLine());
      }
      catch(Exception e) {
	System.out.println("Number format error");
	System.exit(0);
      }
      if(no <= 0) {
	stopSession();
	System.exit(0);
      }
      tstart = new long[no];
      tstop = new long[no];
      System.out.print("Delay      between       messages  : ");
      System.out.flush();
      try {
	delay = Integer.parseInt(br.readLine());
      }
      catch(Exception e) {
	delay = 0;
      }
      if(no < 0) {
	delay = 0;
      }

      t0 = System.currentTimeMillis();
      for(i=0; i<no; i++) {
	tstart[i] = System.currentTimeMillis();
	sendMsg(sbuf);
/*	try {
	  senderThread.suspend();
	}
	catch(Exception e) {
	  System.out.println("Exception in suspend");
	}
*/	try {
	  senderThread.sleep(delay);
	}
	catch(Exception e) {
	  System.out.println("Exception in sleep");
	}
      }
      t1 = System.currentTimeMillis();
      System.out.println("Total send time: " + (t1 - t0) + " msec");
    }
  }


  /**
   * Measures the roundtrip delay for broadcast messages and performs
   * other statistical calculations. 
   */
  public void processBroadcastMessage() {
    int sz=0, i;
    double std=0, mean;

    total += (System.currentTimeMillis() - tstart[cnt++]);
    // tstop[cnt++] = System.currentTimeMillis();

    //System.out.println(cnt + "\t" + (tstop-tstart));
    //System.out.println("t2 - tstart = " + (t2 - tstart));
    //System.out.println("t3 - t2 = " + (t3 - t2));
    //System.out.println("t4 - t3 = " + (myGroup.t4 - t3));
    //System.out.println("t5 - t4 = " + (t5 - myGroup.t4));
    //System.out.println("t6 - t5 = " + (t6 - t5));
    //System.out.println("tstop - t6 = " + (tstop - t6));
    //System.out.println("Tsend = " + t3);
    //System.out.println("Trecv = " + myGroup.t4 + "\n");
    if(cnt == no) {
      //System.out.println("Total recv time: "+(tstop[no-1]-tstop[0]) +"msec");
      cnt = 0;

      /* XXX
      for(i=0; i<no; i++) {
        tstop[i] -= tstart[i];
        total += tstop[i];
      }
      */

      mean = (double)total/no;
      for(i=0; i<no; i++) {
	std += java.lang.Math.pow(tstop[i]-mean, 2);
      }
      std /= no;
      std = java.lang.Math.sqrt(std);
      
      System.out.println("Average latency    : " + mean + "\n");
      //System.out.println("Standard deviation : " + std);
      //System.out.println("Stddev/Avglatency  : " + std/mean);
      total = 0;
    }
    /* try {
      senderThread.resume();
    }
    catch(SecurityException e) {}*/
  }
}


/**
 * The broadcast handler for the TestClient class
 */
class TCBcastHandler extends DVBcastHandler {
  private TestClient myApplet;

  public TCBcastHandler(TestClient myApplet) {
    super();
    this.myApplet = myApplet;
  }

  
  /**
   * Does nothing
   * NOTE: use only in conjunction with serverInfo(). 
   */
  //public void procBcastMsg(String senderGroup, Message aMsg) {}


  /**
   * Informs the applet that a broadcast message has been received . 
   * NOTE: use only in conjunction with action(). 
   */
  public void procBcastMsg(String senderGroup, Message aMsg) {
    int msgType = aMsg.getType();
    //myApplet.t5 = System.currentTimeMillis();
    myApplet.processBroadcastMessage();
  }
}