package com.j2medev.chapter6;

import java.io.*;
import java.util.*;
import javax.microedition.io.*;
import javax.microedition.midlet.*;
import javax.microedition.lcdui.*;
import javax.wireless.messaging.*;

public class MessageMIDlet extends MIDlet implements MessageListener,CommandListener {
    
    private Display display = null;
    private MenuCanvas main = new MenuCanvas(this);
    private MessageConnection receiveConn = null;
    private boolean done = false;
    MessageReader reader = null;
    public static final Command backCommand = new Command("back",Command.BACK,1);
    
    public void startApp() {
        if(display == null){
            display = Display.getDisplay(this);
            display.setCurrent(main);
            //建立服務器端模式的連接
            String serverURL = "mms://:"+this.getAppProperty("Application-ID");
            initMessageServer(serverURL);
            String[] url = PushRegistry.listConnections(true);
            if(url != null && url.length > 0){
                reader.handleMessage();
                //如果MIDlet被短消息激活，那么在接收后設置監聽器
                setMessageListener(receiveConn);
            }else{
                setMessageListener(receiveConn);
                display.setCurrent(main);
            }
        }
    }
    
    public void pauseApp() {
    }
    
    public void destroyApp(boolean unconditional) {
        release();
    }
    
    private void exit(){
        destroyApp(false);
        notifyDestroyed();
    }
    
    private void release(){
        //釋放資源
        done = true;
        try{
            receiveConn.setMessageListener(null);
            receiveConn.close();
            receiveConn = null;
        }catch(IOException ex){
            ex.printStackTrace();
        }
    }
    private void setMessageListener(MessageConnection mc){
        try{
            mc.setMessageListener(this);
        }catch(Exception ex){
            //處理異常
        }
    }
    private void initMessageServer(String url){
        //程序啟動后，建立服務器模式的MessageConnection，監聽短消息
        done = false;
        try{
            receiveConn = (MessageConnection)Connector.open(url);
            //設置監聽器，異步模式等待短信
            reader = new MessageReader();
            new Thread(reader).start();
        }catch(IOException ex){
            displayMessage(ex.getMessage(),main,AlertType.ERROR,"error");
        }
    }
    public void displayMessage(String message,Displayable nextui,AlertType type,String title){
        Alert alert = new Alert(title);
        alert.setType(type);
        alert.setString(message);
        alert.setTimeout(2000);
        display.setCurrent(alert,nextui);
    }
    
    public void displaySuccess(String message){
        displayMessage(message,main,AlertType.CONFIRMATION,"Success");
    }
    
    public void setCurrent(Displayable displayable){
        display.setCurrent(displayable);
    }
    
    public void setMainUI(){
        display.setCurrent(main);
    }
    public void setCurrent(int selected){
        Displayable displayable = null;
        switch(selected){
            case 0:{
                displayable = new SendMMSMessageUI(this);
                break;
            }
            case 1:{
                //fix me
                break;
            }
            case 2:{
                //fix me
                break;
            }
            case 3:{
                exit();
                return;
            }
            default:
                break;
        }
        setCurrent(displayable);
    }
    
    public void notifyIncomingMessage(MessageConnection conn){
        if(conn == receiveConn)
            reader.handleMessage();
    }
    
    public void commandAction(Command cmd,Displayable displayable){
        if(cmd.getCommandType() == Command.BACK){
            display.setCurrent(main);
        }
    }
    class MessageReader implements Runnable{
        
        private int pendingMessage = 0;
        
        public void run(){
            while(!done){
                synchronized(this){
                    //如果沒有消息，則線程等待
                    if(pendingMessage == 0){
                        try{
                            wait();
                        }catch(InterruptedException ex){
                            ex.printStackTrace();
                        }
                    }
                    //讀取消息，pendingMessage--
                    pendingMessage--;
                }
                //接收短信
                Message message = null;
                try{
                    message = receiveConn.receive();
                    
                }catch(IOException ex){
                    //處理異常
                    ex.printStackTrace();
                }
                displayMessage(message);
            }
        }
        
        //短消息進入，喚醒等待的線程讀取消息
        public synchronized void handleMessage(){
            pendingMessage++;//未讀取的消息數增加1
            notify();
        }
        
        private void displayMessage(Message message){
            if(message instanceof TextMessage){
                //不做處理
            }else if( message instanceof BinaryMessage){
                //這里不考慮BinaryMessage的情況
            }else if (message instanceof MultipartMessage){
                //接收多媒體消息并顯示在Form上
                Form form = new Form("mms");
                MultipartMessage mms = (MultipartMessage)message;
                String subject = mms.getSubject();
                form.append("subject:"+subject+"\n");
                String from = mms.getAddress();
                form.append("from:"+from+"\n");
                Date date = mms.getTimestamp();
                form.append("Time:"+parseDate(date));
                MessagePart[] parts = mms.getMessageParts();
                for(int i = 0;i<parts.length;i++){
                    String mimeType = parts[i].getMIMEType();
                    String contentId = parts[i].getContentID();
                    form.append("part"+(i+1)+":"+contentId+"\n");
                    
                    byte[] data = parts[i].getContent();
                    int length = parts[i].getLength();
                    String location = parts[i].getContentLocation();
                    
                    if(mimeType.equals("image/png")){
                        Image img = Image.createImage(data,0,length);
                        form.append(img);
                        form.append("\n");
                    }else if(mimeType.equals("text/plain")){
                        String s = "";
                        try {
                            s = new String(data, parts[i].getEncoding());
                        } catch (UnsupportedEncodingException ex) {
                            ex.printStackTrace();
                        }
                        StringItem text = new StringItem(s,null);
                        text.setLayout(Item.LAYOUT_NEWLINE_BEFORE);
                        form.append(text);
                    }
                }
                form.addCommand(backCommand);
                form.setCommandListener(MessageMIDlet.this);
                display.setCurrent(form);
            }
        }
        //把日期解析為String
        private String parseDate(Date d){
            StringBuffer sb = new StringBuffer();
            Calendar calendar = Calendar.getInstance();
            calendar.setTime(d);
            sb.append(calendar.get(Calendar.YEAR)+"-").append((1+calendar.get(Calendar.MONTH))+"-").
                    append(calendar.get(Calendar.DAY_OF_MONTH));
            return sb.toString();
        }
    }
    
}