/** 
  * Plink: Contacts Database Demonstrator Applet
  * @author Robert J Morton YE572246C
  * @version 25 November 2001 revamped 16 November 2007
  * Converted to a JFramed application  Mon 06 Mar 2017  */

/* Open a terminal and change directory to where this file is loacated.
   To compile this program, enter the terminal command: javac plink.java
   To run this program, enter the terminal command: java plink */

import javax.swing.*;
import java.awt.Dimension;  // to be able to set the preferred JFrame size
import java.awt.Color;      // to be able to set JFrame background colour


public class plink extends JFrame {

  private static final long 
    serialVersionUID = 507L;  // what the hell this is for, I don't know!

  private int
    XE = 515,  // Horizontal extent of window and JFrame. 513 +  2
    YE = 328;  // Vertical extent of window and JFrame.   303 + 25

  private static String[] SW = {"-f","-j","-s"};
  private static int[] LS = {0,1,2};
  private static int ls = 1;  // default is load from jar file

  private static String  // default URL of the class, image and data files 
    cb = "http://localhost/software/java_progs/plink/"; 

  /* Declare a reference to an instance of the child class. Beware:
  an instance of the child class cannot be created here because this 
  must be done within the invokeAndWait environment. */
  private address LG; 


  public plink() {  // construct an instance of this extended JFrame

    //set window frame title on title bar
    super("Plink: Contacts Database Demonstrator Applet");

    /* Set up the window listener to listen for the window close command which
    occurs when the user clicks on the X control in the window's title bar.*/
    setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);

    /* Set the initial size of the extended JFrame. This is the area INSIDE 
    the frame. It does not include the border or the title bar areas. */
    setPreferredSize(new Dimension(XE, YE));

    setBounds(0,0,XE,YE);           // of area inside window frame
    setBackground(Color.black);     // default background colour of JFrame
    LG = new address(XE,YE,ls,cb);  // Create new instance of plink
    getContentPane().add(LG);       // add it to the extended JFrame's pane
    pack();                         // should automatically fill the JFrame
    setVisible(true);               // make this extended JFrame visible
  }


  public static void main(final String[] args) {

    if(argsValid(args)) {

      /* Initiate the creation of a new instance of this extended JFrame then
      wait until the building process has completely finished before giving
      the new instance of the child class permission to commence running. */

      try {
        javax.swing.SwingUtilities.invokeAndWait(
          new Runnable(){public void run(){new plink();}});
      } catch(Exception e) {
        System.out.println("Couldn't create Swing GUI.");
        System.out.println("There's probably an error in the constructor");
        System.out.println("code of one of this class's child classes.");
        System.out.println(e);
        System.out.println(e.getCause()); 
      }
    }   // end of if(argsValid)
  }     // end of main()

  /* The above try-catch sequence is necessary for the following reason. The 
  statement "new plink();" is a request to Swing to create a GUI instance of
  this application. It includes, in effect, all the statements in the constr-
  uctor methods of all this class's child classes. All these requests are made
  on this, the main() program thread. 

  However, these requests are carried out [ie the actual constructing is done]
  by the underlying Swing system on the Event Despatching Thread. The constr-
  ucting process necessarily takes longer to do than the mere task of REQUEST-
  ING that the constructing be done. This means that the main() thread will
  set the run() thread in motion before the GUI has finished being construct-
  ed. Hence trouble.

  The solution is to force the main() thread to withhold permission for the
  run() thread to start its job until the Event Despatching Thread has comp-
  letely finished constructing the GUI. */

  /* NOTE: This class inherits a paint() method from the JFrame class that it
  extends. This method automatically calls the paint() method of the child
  [extended JPanel] class when necessary. */


  private static boolean argsValid(String[] args) {
    int L = args.length;        //number of command-line arguments
    if(L == 0) return true;     //if command line has no arguments
    String s = args[0];         //the first command line argument

    if(s.indexOf("help") != -1) {
      System.out.println("This program accepts command line arguments to");
      System.out.println("say from where it should load its data files:");
      System.out.println("-f = load files from local directory.");
      System.out.println("-j = load files from this app's jar file.");
      System.out.println("-s = load files from a specified server.");
      System.out.println("A URL may be entered after the -s switch.");
      System.out.println("If no URL is given, a default URL is used.");
      return false;
    }
    for(int i = 0; i < 3; i++) {
      if(s.equals(SW[i])) {
        ls = i;
        break;
      }
    }
    if(L < 2) return true;      //no second argument so use default URL
    cb = args[1];               //there must be a second arguement [URL]
    if(!cb.startsWith("http://")) {
      System.out.println("URL has absent or invalid protocol.");
      return false;
    }
    return true;
  }

}  //end of plink class