source: trunk/src/org/expeditee/network/ImageServer.java@ 1510

/**
 *    ImageServer.java
 *    Copyright (C) 2010 New Zealand Digital Library, http://expeditee.org
 *
 *    This program is free software: you can redistribute it and/or modify
 *    it under the terms of the GNU General Public License as published by
 *    the Free Software Foundation, either version 3 of the License, or
 *    (at your option) any later version.
 *
 *    This program is distributed in the hope that it will be useful,
 *    but WITHOUT ANY WARRANTY; without even the implied warranty of
 *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *    GNU General Public License for more details.
 *
 *    You should have received a copy of the GNU General Public License
 *    along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

package org.expeditee.network;

import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.ServerSocket;
import java.net.Socket;

import org.expeditee.gui.FrameIO;

public class ImageServer extends DefaultServer {
        
        public static void sendImage(File file, Socket socket) throws IOException {
                if(!file.isFile()) {
                        System.out.println("Could not find " + file.getName());
                        return;
                }
                OutputStream os = socket.getOutputStream();
        // send the file over the socket
        int fileLen = (int) file.length();
        System.out.println("Sending " + file.getName() + " (" + fileLen + " bytes)");
        byte[] fileLenBytes = new byte[4];
        fileLenBytes[0] = (byte) ((fileLen >> 24) & 0xFF);
        fileLenBytes[1] = (byte) ((fileLen >> 16) & 0xFF);
        fileLenBytes[2] = (byte) ((fileLen >> 8) & 0xFF);
        fileLenBytes[3] = (byte) ((fileLen) & 0xFF);
        os.write(fileLenBytes);
        FileInputStream in = new FileInputStream(file);
        byte[] buf = null;
        if(in.available() > 1024) {
                buf = new byte[1024];
                while(in.available() > 1024) {
                        in.read(buf);
                        os.write(buf);
                }
        }
        buf = new byte[in.available()];
        in.read(buf);
                os.write(buf);
                os.flush();
                in.close();
        }
        
        /**
         * Reads an image request, and sends the image back if it was found
         * 
         * @author jts21
         *
         */
        private static class ImageSender extends Thread {
                
                private Socket socket;
                
                public ImageSender(Socket client) {
                        super("ImageSender");
                        this.socket = client;
                }
                
                @Override
                public void run() {
                        try {
                                InputStream is = this.socket.getInputStream();
                                // file name length is the first byte
                    int fileNameLen = is.read();
                    if(fileNameLen <= 0)
                        return;
                    // file name is the remaining bytes of the stream, encoded in UTF-8
                    byte[] fileName = new byte[fileNameLen];
                    is.read(fileName);
                    sendImage(new File(FrameIO.IMAGES_PATH + new String(fileName, FrameShare.CHARSET)), socket);
                this.socket.close();
            } catch (IOException e) {
                    e.printStackTrace();
            }
                }
        }
        
        public final static int OFFSET = 5;
        
        private ServerSocket socket;

        public ImageServer(int port) throws IOException {
                super("ImageServer");
                this.socket = new ServerSocket(port + OFFSET);
        }

        @Override
        protected void listenForMessages() throws IOException {
                Socket client = socket.accept();
                // should probably only allow a limited number of threads here
                new ImageSender(client).start();
        }
        
        @Override
        protected void closeSocket() {
                try {
                        socket.close();
                } catch (IOException e) {
                        e.printStackTrace();
                }
        }

}