package com.j2medev.chapter9;

import java.io.*;
import java.util.Vector;
import javax.bluetooth.*;
import javax.microedition.io.*;

public class BTServer implements Runnable {
    
    //存儲BTMIDlet實例，方便回調
    private BTMIDlet midlet = null;
    private LocalDevice device = null;
    private StreamConnectionNotifier server = null;
    private ConnectionHandle handle = null;
    private boolean stop = false;
    
    public BTServer(BTMIDlet _midlet) {
        this.midlet = _midlet;
    }
    
    public void run() {
        try {
            device = LocalDevice.getLocalDevice();
            device.setDiscoverable(DiscoveryAgent.GIAC);
            UUID u = new UUID(0x0001);
            //啟動SPP服務器
            server = (StreamConnectionNotifier)Connector.open("btspp://localhost:"+u.toString());
            midlet.btServerReady();
            handle = new ConnectionHandle();
            while(!stop){
                StreamConnection conn = null;
                try {
                    //將ServiceRecord注冊到SDDB
                    conn = server.acceptAndOpen();
                } catch (IOException ex) {
                    ex.printStackTrace();
                    continue;
                }
                //處理客戶端的連接
                handle.addConnection(conn);
            }
        } catch (BluetoothStateException ex) {
            ex.printStackTrace();
        } catch (IOException ex) {
            ex.printStackTrace();
        }
    }
    //根據連接的類型，進行不同方式的處理
    private void processConnection(Connection _conn){
        if(_conn instanceof StreamConnection){
            StreamConnection conn = (StreamConnection)_conn;
            try {
                //流連接
                InputStream is = conn.openInputStream();
                byte[] buffer = new byte[1024];
                int ch = -1;
                ByteArrayOutputStream baos = new ByteArrayOutputStream();
                while((ch = is.read(buffer))!= -1){
                    baos.write(buffer,0,ch);
                }
                byte[] img = baos.toByteArray();
                midlet.imageReceived(img);
                is.close();
                baos.close();
                conn.close();
            } catch (IOException ex) {
                ex.printStackTrace();
            }
        }else if(_conn instanceof L2CAPConnection){
            L2CAPConnection conn = (L2CAPConnection)_conn;
            try {
                //要充分考慮最大接受單元，避免丟失數據
                int max = conn.getReceiveMTU();
                byte[] buffer = new byte[max];
                int len = 0;
                ByteArrayOutputStream baos = new ByteArrayOutputStream();
                while(conn.ready()&&(len = conn.receive(buffer)) != -1){
                    baos.write(buffer,0,len);
                }
                byte[] img = baos.toByteArray();
                midlet.imageReceived(img);
                baos.close();
                conn.close();
            } catch (IOException ex) {
                ex.printStackTrace();
            }
        }
    }
    
    private class ConnectionHandle implements Runnable{
        
        private Thread t = null;
        //存儲客戶端連接
        private Vector conns = new Vector();
        
        ConnectionHandle(){
            t = new Thread(this);
            t.start();
        }
        
        public void run(){
            while(!stop){
                //如果conns為空，則線程進入等待狀態
                synchronized (this){
                    try {
                        if(conns.size() == 0)
                            wait();
                    } catch (InterruptedException ex) {
                        ex.printStackTrace();
                    }
                }
                StreamConnection conn = null;
                synchronized (this){
                    //取出第一個連接并刪除掉
                    conn = (StreamConnection)conns.elementAt(0);
                    conns.removeElementAt(0);
                    //開始處理
                    processConnection(conn);
                }
            }
        }
        
        void addConnection(StreamConnection _conn){
            //新連接到來，喚醒線程處理
            synchronized(this){
                conns.addElement(_conn);
                notify();
            }
        }
    }
}