package com.digi.config.util;


import java.awt.Cursor;
import java.util.Stack;
import java.awt.Component;
import javax.swing.JLabel;


/**
 * This class is used for putting up the busy cursor when in gui mode
 */

public class Busy {
    private static StatusDisplay guiComponent   =null;
    private static Stack messages    =new Stack();
    private static String initialMsg ="";

    /**
     * This method registers the GUI Component that the busy cursor is to be
     * displayed in. This should be done once at the beginning of the application
     * <p>
     * @param theComponent the gui component to show the busy cursor and status text (implements
     * the StatusDisplay interface.
     */
    public static void registerGUIComponent(StatusDisplay theComponent) {
        guiComponent=theComponent;
        // Finish this...
        // provide support such that if no gui component is passed in, then we put up
        // a temporary busy dialog that informs the user that work is in progress and
        // what the current message is.
    }


    /**
     * This method turns on the busy cursor. If the cursor is already
     * on, it bumps a count of the number of busy sections.
     * <p>
     * Note: If no component is registered, then this method does nothing.
     */
    public static void begin(String msg) {
        try {
            String lastMsg="";
            // if Just turning busy, turn on busy cursor
            if (messages.isEmpty()) {
                if (guiComponent!=null) {
                    initialMsg=guiComponent.getStatusText();
                    lastMsg=initialMsg;
                }
            }
            else {
                lastMsg=(String)messages.peek();
            }

            // Use message passed in. If none passed in, then use previous busy message
            if ((msg==null)||(msg.trim().length()==0)) {
                msg=lastMsg;
            }

            // push this message on the message stack && update the message area
            messages.push(msg);
            if (guiComponent!=null) {
                guiComponent.updateStatus(true, msg);
            }
        }
        catch (Exception e) {
            // finish this... msg work
            SystemLog.log("Internal Error: ending busy cursor");
            SystemLog.log(e);
        }
    }

    public static void begin() {
        begin(null);
    }

    /**
     * This method decrements the count of busy sections by one. When the count reaches
     * zero, this method turns off the busy cursor.
     * <p>
     * Note: If no component is registered, then this method does nothing.
     */
    public static void end() {
        String lastMsg="";
        try {
            messages.pop();
            if (messages.isEmpty()) {
                lastMsg=initialMsg;
            }
            else {
                lastMsg=(String)messages.peek();
            }
        }
        catch (Exception e) {
            // finish this... msg work
            SystemLog.log("Internal Error: ending busy cursor");
            SystemLog.log(e);
        }
        if (guiComponent!=null) {
            guiComponent.updateStatus(false, lastMsg);
        }
    }

}