/* Copyright 2000 Charles G. Wright
 * This software may be distributed under the terms of the
 * GNU General Public License.
 *
 * $Id: GRAgraphs.java,v 1.1 2000-06-15 10:14:56-05 chuckles Exp chuckles $
 */

import java.awt.*;
import java.awt.event.*;
import java.io.*;
import java.util.*;

/** <p>Class implementing several graphs and a data selector.
 * There are two subpanels. One of these is a List object
 * that shows all displayable data elements.
 * <p> The other of these is a panel that shows one of
 * several graphs, plus buttons that page through the various
 * available graphs.
 */

public class GRAgraphs extends Panel implements ActionListener, ItemListener, TMYgraphMaster {

  public CWObservable obs;
  private Button next;
  private Button previous;
  private java.awt.List fieldList;
  public TMYdata tmystuff;
  private Panel graph_panel_top;
  private Panel graph_panel;
  private Panel title_panel;
  private Label graph_title;
  private Label l1;
  private Color[] colors;
  private CardLayout graph_panel_layout;

  /** Creates a panel containing a selection list on the left,
   * plus a panel on the right that shows one of several graphs. */

  public GRAgraphs(Color[] colors){

    // This CWObservable keeps track of the GRAgraph objects that
    // are managed by this GRAgraphs, and handles updates that
    // are required when the fieldList selections are changed.

    obs = new CWObservable();

    fieldList = new java.awt.List(10, true);

    // Register it to receive monitorable elements
    CWmonitoredElements.addList(fieldList);
    fieldList.addItemListener(this);

    this.colors = colors;

    //-------------------------------------------------
    // title panel creation
    FlowLayout fl = new FlowLayout(FlowLayout.LEFT, 2, 2);
    title_panel = new Panel(fl);
    
    l1 = new Label("Graph selection:");
    title_panel.add(l1);
    previous = new Button("<");
    previous.addActionListener(this);
    title_panel.add(previous);

    next = new Button(">");
    next.addActionListener(this);
    title_panel.add(next);

    // End of title panel definition
    //----------------------------------------------
    // graph panel definition
    graph_panel = new Panel();
    graph_panel_layout = new CardLayout();
    graph_panel.setLayout(graph_panel_layout);
    // We don't add anything to it right away.
    //End of graph panel definition

    //-------- top graph panel definition -----------
    graph_panel_top = new Panel();
    GridBagLayout top_graph_layout = new GridBagLayout();
    graph_panel_top.setLayout(top_graph_layout);

    GridBagConstraints ct = new GridBagConstraints();
    ct.fill = GridBagConstraints.BOTH;
    ct.gridwidth = GridBagConstraints.REMAINDER;
    ct.weightx = 1.0;
    ct.weighty = 0.0;
    ct.gridx = 0;
    top_graph_layout.setConstraints(title_panel, ct);

    ct.fill = GridBagConstraints.BOTH;
    ct.weighty = 1.0;
    top_graph_layout.setConstraints(graph_panel, ct);
    graph_panel_top.add(title_panel);
    graph_panel_top.add(graph_panel);
    //-------- end of top graph panel layout --------

    //--------- top level layout --------------------
    GridBagLayout top_layout = new GridBagLayout();
    setLayout(top_layout);
    // put field list on the left
    GridBagConstraints c0l = new GridBagConstraints();
    c0l.fill = GridBagConstraints.BOTH;
    c0l.weightx = 0.3;
    c0l.weighty = 1.0;
    c0l.gridx = 0;
    c0l.insets = new Insets(3,3,3,3);
    top_layout.setConstraints(fieldList, c0l);
    // put graph panel on the right
    c0l.weightx = 1.0;
    top_layout.setConstraints(graph_panel_top, c0l);
    //--------- End of top level layout

    add(fieldList);
    add(graph_panel_top);
  }

  public TMYdata getTMY(){
    return(tmystuff);
  }

  public java.awt.List getFieldList(){
    return(fieldList);
  }

  public void paint(Graphics g){
    setForeground(Color.black);
    Dimension d = getSize();
    g.drawRect(0, 0, d.width - 1, d.height - 1);
  }

  /** Adds a graph to be displayed. */

  public void addGraph(GRAgraph graph, String name){
    graph_panel.add(graph, name);
    obs.addObserver(graph);
  }

  /** Event handler to handle button presses. In this case,
   * the class has 2 buttons, to left or right scroll through
   * the available graphs. */

  public void actionPerformed(ActionEvent ae){

    Object sel = ae.getSource();

     // Handle interactions between month and day selectors.
    if (sel == previous){
      graph_panel_layout.previous(graph_panel);
    } else if (sel == next){
      graph_panel_layout.next(graph_panel);
    }
  }

  /** Event handler for changes to the list of displayable elements. */
  public void itemStateChanged(ItemEvent e){
    obs.setChanged();
    obs.notifyObservers(this);
    // This will cause obs to issue an update(obs, this) to each of
    // the graphs owned by this.
    System.out.println("item listener invoked");
  }
}