/** 
  * Message Panel for the Moving Map Navigator
  * @author Robert J Morton YE572246C
  * @version 12 December 2007
  * @copyright Robert J Morton (all rights reserved) */


import javax.swing.*;     // Java Swing GUI utilities
import java.awt.*;        // Java Abstract Windowing Toolkit
import java.awt.event.*;  // for the new-fangled 1.1 event handling


class msgpanel extends JPanel {  // TO DISPLAY ERROR AND PROGRESS MESSAGES

  private static final long 
    serialVersionUID = 15L;  // what the hell this is for, I don't know!

  private static msgpanel mp;  // reference to current instance of this class
  private boolean 
    progressMsg = true,  // true if a progress message, not an error message
    imageLoad = false,   /* true = image load failure, 
                            false = route/waypoints load failure. */
    b = false;  // background photo not yet loaded

  private int
    Lx =  15,      // x-coord of top left corner of panel within applet
    Ly = 480,      // y-coord of top left corner of panel within applet
    Lw = 406,      // width of panel
    Lh =  35,      // height of panel
    Bw =  80,      // button width
    Mw = Lw - Bw,  // width of message area
    Ti = 10,       // text inset from start of message area
    q = Bw + Ti,   // x-bias for printing directly on panel or on image
    My,            // y-origin of the message line
    L;             // language switch

  private String
    S[] = {"Retry","Tentar"},
    msg = "";  // to contain the current message to be displayed

  private movmap mm;  // reference to current instance of the movmap applet
  private loader ld;  // reference to the current instance of the data loader

  // button for retrying to load a route names or waypoint list
  private JButton RtryBut;

  private Font font;  // ref for large and small fonts used in this applet
  private FontMetrics fm;  // typeface dimensions for the above fonts
  private Color fg, fgc;   // foreground colour


  msgpanel(movmap mm, Color fg, int L) {
    this.mm = mm;
    this.fg = fg;  // foreground colour (for lettering)
    mp = this;     // reference to this instance of this class
    this.L = L;
    setLayout(null);    // to allow the control panels to be laid out manually
    fgc = Color.black;  // initial foreground colour before images are loaded

    font = new Font("Serif",Font.BOLD,16);  // font for applet canvas
    fm = getFontMetrics(font);  // get letter dimensions etc for this font
    My = (Lh + fm.getAscent()) >> 1;  // vertical base line offset

    /* Create the "Retry" button, set its position
    and size then create a listener for it. */

    RtryBut = new JButton("");
    add(RtryBut);
    RtryBut.setBounds(0,0,Bw,Lh);
    RtryBut.addActionListener(new rtlisten(rtlisten.RTRYBUT, this));
  }


  void setLoader(loader ld) { this.ld = ld; }
  void changeColour() { fgc = fg; b = true; }


  // DISPLAY ON INITIALIZATION OR WHEN APPLET IS UNECLIPSED
  public void paint(Graphics g) {
    super.paint(g);  // paint the retry button
    if(b)  // if background photo available, draw it on the applet panel
       g.drawImage(movmap.IMG4,Bw,0,this);
    else {
      g.setColor(getBackground());  // clear the field by
      g.fillRect(Bw, 0, Mw, Lh);    // filling it with background colour
    }
    g.setFont(font);          // use the big bold font
    if(progressMsg) {         // if in the process of loading
      RtryBut.setForeground(Color.lightGray); 
      RtryBut.setText(S[L]);  // kill label on retry button
      g.setColor(fgc);        // display route information in black lettering
    } else {                  // else it must be an error condition
      RtryBut.setForeground(Color.black); 
      RtryBut.setText(S[L]);  // change label on retry button to "Retry"
      g.setColor(Color.red);  // display error message in red lettering
    }
    g.drawString(msg,q,My);   // display the message
  }


  void showMsg(String msg, boolean progressMsg, boolean imageLoad) {
    this.msg = msg;
    this.progressMsg = progressMsg;
    this.imageLoad = imageLoad;
    repaint();  // gets graphics reference and calls update(g)
  }


  void pressRtryBut() {     // RE-TRY BUTTON TO ATTEMPT A RELOAD AFTER AN ERROR
    if(progressMsg)         // if it's not an error message,
      return;               // then exit now
    if(imageLoad) {         // if error occurred during image loading
      RtryBut.setText("");  // kill the label of the retry button
      mm.imgReload();       // command to reload all images
    }

    /* Else, the error must have occurred during the loading
    of the routes data. So, if it were a connecting or loading
    error, kill the label of the retry button, wipe the error
    message then re-initiate the loading sequence. */

    else {
      if(ld.getlp() > 3) {
        RtryBut.setText("");
        showMsg("",true,false);
        ld.setlp(1);
      } 
    }
  }    // error conditions tested and found to be working correctly
}



// LISTENS FOR EVENTS FROM THE BUTTONS
class rtlisten implements ActionListener {
  static final int 
    RTRYBUT = 3;  // 're-try button pressed' event
  int id;         // one of the above
  msgpanel ap;    // the application that called: always the above panel

  // constructor for a new command
  public rtlisten(int id, msgpanel ap) { this.id = id; this.ap = ap; }

  // one of the buttons has been clicked
  public void actionPerformed(ActionEvent e) {
    switch(id) {           // id of this instance of ActionEvent
      case RTRYBUT:        // it was the 're-try' button
        ap.pressRtryBut();
    }
  }
}