/*
 * SIP Communicator, the OpenSource Java VoIP and Instant Messaging client.
 *
 * Distributable under LGPL license.
 * See terms of license at gnu.org.
 *
 * SSHReaderDaemon.java
 *
 * SSH Suport in SIP Communicator - GSoC' 07 Project
 *
 */
package net.java.sip.communicator.impl.protocol.ssh;

import java.io.*;

import net.java.sip.communicator.service.protocol.*;

/**
 *
 * @author Shobhit Jindal
 */
public class SSHReaderDaemon
        extends Thread
{

    /**
     * A Buffer to aggregate replies to be sent as one message
     */
    private StringBuffer replyBuffer;
    
    /**
     * The identifier of Contact representing the remote machine
     */
    private ContactSSHImpl sshContact;
    
    /**
     * The identifier of the message received from server
     */
    private String message;
    
    /**
     * An identifier representing the state of Reader Daemon
     */
    private boolean isActive = false;
    
    /**
     * This OperationSet delivers incoming message
     */
    private OperationSetBasicInstantMessagingSSHImpl instantMessaging;
    
    /**
     * Input Stream of remote user to be read
     */
    private InputStream shellInputStream;
    
    /**
     * Buffered Reader associated with above input stream
     */
    private InputStreamReader shellReader;
    
//    /**
//     * This OperationSet delivers incoming message
//     */
//    private OperationSetPersistentPresenceSSHImpl persistentPresence;
    
    /**
     * Bytes available in Input Stream before reading
     */
    private int bytesAvailable;
    
    private int bytesRead;
    
    int bufferCount;
    
    char buf;
    
    /**
     * Creates a new instance of SSHReaderDaemon
     */
    public SSHReaderDaemon(ContactSSH sshContact)
    {
        this.sshContact = (ContactSSHImpl)sshContact;
        instantMessaging =
            (OperationSetBasicInstantMessagingSSHImpl)
                sshContact
                    .getProtocolProvider()
                        .getOperationSet(
                            OperationSetBasicInstantMessaging.class);
    }
    
    /**
     * Reads the remote machine, updating the chat window as necessary
     * in a background thread
     */
    public void run()
    {
        shellInputStream = sshContact.getShellInputStream();
        shellReader = sshContact.getShellReader();
        replyBuffer = new StringBuffer();

        
        try
        {
            do
            {
                bytesAvailable = shellInputStream.available();
                
                if(bytesAvailable == 0 )
                {
                    // wait if more data is available
                    // for a slower connection this value need to be raised
                    // to avoid splitting of messages
                    Thread.sleep(250);
                    continue;
                }
                
                bufferCount = 0;
                
//                if(replyBuffer > 0)
                
                do
                {
                    // store the responses in a buffer
                    storeMessage(replyBuffer);
                    
                    Thread.sleep(250);
                    
                    bytesAvailable = shellInputStream.available();
                    
                }while(bytesAvailable > 0  && bufferCount<16384);
                
                message = replyBuffer.toString();
                
                if(sshContact.isCommandSent())
                {
                    // if the response is as a result of a command sent
                    sshContact.setMessageType(sshContact
                            .CONVERSATION_MESSAGE_RECEIVED);
                    
                    message = message.substring(message.indexOf('\n') + 1);
                    
                    sshContact.setCommandSent(false);
                }
                else
                {
                    // server sent an asynchronous message to the terminal
                    // display it as a system message
                    sshContact.setMessageType(sshContact
                            .SYSTEM_MESSAGE_RECEIVED);
                    
                    //popup disabled
//                    JOptionPane.showMessageDialog(
//                            null,
//                            message,
//                            "Message from " + sshContact.getDisplayName(),
//                            JOptionPane.INFORMATION_MESSAGE);
                }
                
                instantMessaging.deliverMessage(
                        instantMessaging.createMessage(message),
                        sshContact);
                
                replyBuffer.delete(0, replyBuffer.length());
                
            }while(isActive);
        }
        catch(Exception ex)
        {
            ex.printStackTrace();
        }
    }
    
    /**
     * Stores the response from server in a temporary buffer
     * the bytes available are determined before the function is called
     *
     * @param replyBuffer to store the response from server
     *
     * @throws IOException if the network goes down
     */
    private void storeMessage(StringBuffer replyBuffer) throws IOException
    {
        do
        {
            buf = (char)shellInputStream.read();
            
//            System.out.println(String.valueOf(buf)+ " " + (int)buf);
            
            replyBuffer.append(String.valueOf(buf));
            
//                    logger.debug(shellReader.readLine());
            
            bufferCount++;
            
            bytesAvailable--;
            
        }while(bytesAvailable>0 && bufferCount<32700);
    }
    
    public void isActive(boolean isActive)
    {
        this.isActive = isActive;
    }
}