/*
  Graph File Viewer & Editing Utility
     Steven Hansen
     CSE690
 */


   package EDU.auburn.VGJ.gui;



   import java.awt.Frame;
   import java.awt.Event;
   import java.awt.TextArea;
   import java.awt.TextField;
   import java.awt.Panel;
   import java.awt.BorderLayout;
   import java.awt.GridLayout;
   import java.awt.Button;
   import java.awt.MenuBar;
   import java.awt.MenuItem;
   import java.awt.Menu;
   import java.awt.Color;
   import java.awt.Label;
   import java.awt.Component;
   import java.io.StringBufferInputStream;
   import java.io.IOException;
   import java.lang.NumberFormatException;
   import EDU.auburn.VGJ.graph.Graph;
   import EDU.auburn.VGJ.graph.GMLobject;
   import EDU.auburn.VGJ.graph.GMLlexer;
   import EDU.auburn.VGJ.algorithm.GraphUpdate;
   import EDU.auburn.VGJ.graph.ParseError;


/**
 *	GraphEdit is a text editing window for Graphs
 *	</p>Here is the <a href="../gui/GraphEdit.java">source</a>.
 *
 *@author	Steven Hansen
**/

   public class GraphEdit extends Frame {
   
      private Graph graph_;
      private GraphUpdate update_;
      private static TextArea textarea_;
      private static String originalGraphSpec_;   
      private TextField text1, text2;
      private Label label1, label2;
      private Button okButton, cancelButton;
      private static String lastaction = "";
      private boolean firstTime_ = true;
   
      public GraphEdit(Graph graph_in, GraphUpdate update_in) {
      
         setTitle("Text Edit " + update_in.getFrame().getTitle() + " (GML)");
      
         graph_ = graph_in;
      
         GMLobject GMLgraph = new GMLobject("graph", GMLobject.GMLlist);
         graph_.setGMLvalues(GMLgraph);
         GMLgraph.prune();
      
         update_ = update_in;
      
         Panel topPanel = new Panel();
         Panel bottomPanel = new Panel();
         Panel centerPanel = new Panel();
         setLayout(new BorderLayout());
      
        //Set up the menu bar.
         MenuBar mb = new MenuBar();
         Menu m = new Menu("Menu");
         m.add(new MenuItem("Apply Changes"));
         m.add(new MenuItem("-"));
         m.add(new MenuItem("Exit"));
         mb.add(m);
         Menu m2 = new Menu("Edit");
         m2.add(new MenuItem("GoToTop"));
         m2.add(new MenuItem("GoToBottom"));
         m2.add(new MenuItem("GoToLine"));
         m2.add(new MenuItem("Search"));
         m2.add(new MenuItem("Replace"));
         mb.add(m2);
         setMenuBar(mb);
      
      //add editing controls to the top of the window
         okButton = new Button("Apply");
         cancelButton = new Button("Done");
         text1 = new TextField(15);
         text1.setBackground(Color.white);
         text2 = new TextField(15);
         text2.setBackground(Color.white);
         label1 = new Label("Search for:");
         label2 = new Label("    Replace all with:");
      
         topPanel.add(label1);
         topPanel.add(text1);
         topPanel.add(label2);
         topPanel.add(text2);
         topPanel.add(okButton);
         topPanel.add(cancelButton);
         add("North", topPanel);
      
        //Add small things at the bottom of the window.
         bottomPanel.add(new Button("Apply Changes"));
         bottomPanel.add(new Button("Exit"));
         add("South", bottomPanel);
      
        //Add big things to the center area of the window.
         centerPanel.setLayout(new GridLayout(1,2));
         Panel p = new Panel();
         p.setLayout(new BorderLayout());
         p.add("North", new Label("Edit Graph Below; Press \"Apply Changes\" to update the graph.", Label.CENTER));
         originalGraphSpec_ = GMLgraph.toString(0);
         textarea_ = new TextArea(originalGraphSpec_, 24, 80);
         textarea_.setBackground(Color.white);
         p.add("Center",  textarea_);
         centerPanel.add(p);
         add("Center", centerPanel);
      
         hideAll_();
      }
   
      public boolean action(Event event, Object arg)  {
         if (((String)arg).equals("GoToTop")) {
            textarea_.select(0, 0);
            return true;
         }
         if (((String)arg).equals("GoToBottom")) {
            textarea_.select(textarea_.getText().length(),
                             textarea_.getText().length());
            return true;
         }
         if (((String)arg).equals("GoToLine")) {
            hideAll_();
            buttonLabels_();
            label1.show();
            label1.setText("Go To Line #:");
            text1.show();
            okButton.show();
            cancelButton.show();
            lastaction = "Line";
            validate();
            pack();
            textarea_.requestFocus();
            return true;
         }
         if (((String)arg).equals("Search")) {
            hideAll_();
            buttonLabels_();
            label1.show();
            label1.setText("Search for:");
            text1.show();
            okButton.show();
            cancelButton.show();
            lastaction = "Search";
            validate();
            pack();
            text1.setText("");
            textarea_.requestFocus();
            return true;
         }
         if (((String)arg).equals("Replace")) {
            hideAll_();
            buttonLabels_();
            label1.show();
            label1.setText("Search for:");
            text1.show();
            label2.show();
            text2.show();
            okButton.show();
            cancelButton.show();
            lastaction = "Replace";
            validate();
            pack();
            text1.setText("");
            text2.setText("");
            textarea_.requestFocus();
            return true;
         }
         if (((String)arg).equals("Apply")) {
            if (lastaction.equals("Search")) {
               String text = textarea_.getText();
               String lookfor = text1.getText().trim();
               int start = textarea_.getSelectionEnd();
               int where = text.indexOf(lookfor, start);
               if(where == -1)  // Wrap around.
                  where = text.indexOf(lookfor);
               if(where != -1)
                  textarea_.select(where, where + lookfor.length());
            }
            else if (lastaction.equals("Replace")) {
               String lookfor = text1.getText();
               int lookfor_len = lookfor.length();
               if(lookfor_len > 0)
               {
                  int where;
                  String text = textarea_.getText();
                  String new_text = "";
                  String replace_with = text2.getText();
                  int prev_where = 0;
                  while((where = text.indexOf(lookfor, prev_where)) != -1)
                  {
                     new_text += text.substring(prev_where, where);
                     new_text += replace_with;
                     prev_where = where + lookfor_len;
                  }
                  if(prev_where < text.length())
                     new_text += text.substring(prev_where, text.length());
                  textarea_.setText(new_text);
               }
            }
            else if (lastaction.equals("Line")) {
               int whichline;
               try
               { whichline = Integer.parseInt(text1.getText().trim()); }
                  catch(NumberFormatException e)
                  { whichline = -1; }
            
               String text = textarea_.getText();
               int start, end, count;
            
               start = -1;
               for(count = 0; count < whichline - 1; count++)
               {
                  start = text.indexOf("\n", start + 1);
                  if(start == -1)
                     break;
               }
            
               if(start != -1 || whichline == 1)
               {
                  end = text.indexOf("\n", start + 1);
                  if(end == -1)
                     end = text.length() - 1;
                  textarea_.select(start + 1, end);
               }
               else if(start == -1 && whichline > 0)
               {
                  end = text.length();
                  start = text.lastIndexOf("\n", end - 1);
                  if(start == -1)
                     start = 0;
                  textarea_.select(start + 1, end);
               }
            
            }
         
            textarea_.requestFocus();
            return true;
         }
         else if (((String)arg).equals("Done")) {
            hideAll_();
            lastaction = "";
         
            validate();
            pack();
         
            textarea_.requestFocus();
            return true;
         }
         else if(((String)arg).equals("Find"))
         // Find.
         {
            String lookfor = textarea_.getSelectedText();
            if(lookfor.length() > 0)
            {
               String text = textarea_.getText();
               int pos = textarea_.getSelectionStart();
               int where = text.indexOf(lookfor, pos + 1);
               if(where == -1)
               // Wrap around.
                  where = text.indexOf(lookfor);
               if(where == -1)
                  return false;
               textarea_.select(where, where + lookfor.length());
            }
            textarea_.requestFocus();
         }
         else if(((String)arg).equals("Find Backwards"))
         // Find backwards.
         {
            String lookfor = textarea_.getSelectedText();
            if(lookfor.length() > 0)
            {
               String text = textarea_.getText();
               int pos = textarea_.getSelectionStart();
               int where = text.lastIndexOf(lookfor, pos - 1);
               if(where == -1)
               // Wrap around.
                  where = text.lastIndexOf(lookfor, text.length() - 1);
               if(where == -1)
                  return false;
               textarea_.select(where, where + lookfor.length());
            }
         
            textarea_.requestFocus();
         }
      
      
         if (((String)arg).equals("Exit")) {
            dispose();
         }
         if (((String)arg).equals("Apply Changes")) {
           // perform a graph update here...need to pass text to graph object
         
            String text = textarea_.getText();
            StringBufferInputStream stream = new StringBufferInputStream(text);
            GMLlexer lexer = new GMLlexer(stream);
         
            Graph newgraph = null;
            try
            {
               GMLobject GMLgraph = new GMLobject(lexer, null);
               GMLobject GMLtmp;
            
               // If the GML doesn't contain a graph, assume it is a graph.
               GMLtmp = GMLgraph.getGMLSubObject("graph", GMLobject.GMLlist, false);
               if(GMLtmp != null)
                  GMLgraph = GMLtmp;
               newgraph = new Graph(GMLgraph);
            
               graph_.copy(newgraph);
               update_.update(true);
            }
               catch(ParseError error)
               {
                  MessageDialog dg = new MessageDialog(this,
                                                      "Error", error.getMessage() +
                                                      " at line " + lexer.getLineNumber() + " at or near \""
                                                      + lexer.getStringval() + "\".", true);
                  return true;
               }
               catch(IOException error)
               {
                  MessageDialog dg = new MessageDialog(this,
                                                      "Error", error.getMessage(), true);
                  return true;
               }
            textarea_.requestFocus();
         }
         return true;
      }
   
      public boolean handleEvent(Event event) {
         if(firstTime_)
         {
            firstTime_ = false;
            textarea_.requestFocus();
         }
         if (event.id == Event.WINDOW_DESTROY)
         {
            dispose();
            return true;
         }
         return super.handleEvent(event);
      }
   
   
      private void hideAll_()
      {
         label1.hide();
         text1.hide();
         label2.hide();
         text2.hide();
      
         okButton.setLabel("Find");
         cancelButton.setLabel("Find Backwards");
      }
   
      private void buttonLabels_()
      {
         okButton.setLabel("Apply");
         cancelButton.setLabel("Done");
      }
   
   }