package net.sf.clipsrules.jni.examples.animal;

import javax.swing.*; 
import javax.swing.border.*; 
import javax.swing.table.*;
import java.awt.*; 
import java.awt.event.*; 

import java.io.FileNotFoundException;

import java.text.BreakIterator;

import java.util.Locale;
import java.util.ResourceBundle;
import java.util.MissingResourceException;

import java.util.ArrayList;
 
import net.sf.clipsrules.jni.*;

/* Implement FindFact which returns just a FactAddressValue or null */
/* TBD Add size method to PrimitiveValue */

/*

Notes:

This example creates just a single environment. If you create multiple environments,
call the destroy method when you no longer need the environment. This will free the
C data structures associated with the environment.

   clips = new Environment();
      .
      . 
      .
   clips.destroy();

Calling the clear, reset, load, loadFacts, run, eval, build, assertString,
and makeInstance methods can trigger CLIPS garbage collection. If you need
to retain access to a PrimitiveValue returned by a prior eval, assertString,
or makeInstance call, retain it and then release it after the call is made.

   PrimitiveValue pv1 = clips.eval("(myFunction foo)");
   pv1.retain();
   PrimitiveValue pv2 = clips.eval("(myFunction bar)");
      .
      .
      .
   pv1.release();

*/

class AnimalDemo implements ActionListener
  {  
   private enum InterviewState 
     {
      GREETING,
      INTERVIEW,
      CONCLUSION
     };

   JLabel displayLabel;
   JButton nextButton;
   JButton prevButton;
   JPanel choicesPanel;
   ButtonGroup choicesButtons;
   ResourceBundle animalResources;

   Environment clips;
   boolean isExecuting = false;
   Thread executionThread;

   String lastAnswer;
   String relationAsserted;
   ArrayList<String> variableAsserts;
   ArrayList<String> priorAnswers;

   InterviewState interviewState;

   AnimalDemo()
     {  
      try
        {
         animalResources = ResourceBundle.getBundle("net.sf.clipsrules.jni.examples.animal.resources.AnimalResources",Locale.getDefault());
        }
      catch (MissingResourceException mre)
        {
         mre.printStackTrace();
         return;
        }

      /*================================*/
      /* Create a new JFrame container. */
      /*================================*/
     
      JFrame jfrm = new JFrame(animalResources.getString("AnimalDemo"));  
 
      /*=============================*/
      /* Specify FlowLayout manager. */
      /*=============================*/
        
      jfrm.getContentPane().setLayout(new GridLayout(3,1));  
 
      /*=================================*/
      /* Give the frame an initial size. */
      /*=================================*/
     
      jfrm.setSize(350,200);  
  
      /*=============================================================*/
      /* Terminate the program when the user closes the application. */
      /*=============================================================*/
     
      jfrm.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);  
 
      /*===========================*/
      /* Create the display panel. */
      /*===========================*/
      
      JPanel displayPanel = new JPanel(); 
      displayLabel = new JLabel();
      displayPanel.add(displayLabel);
      
      /*===========================*/
      /* Create the choices panel. */
      /*===========================*/
     
      choicesPanel = new JPanel(); 
      choicesButtons = new ButtonGroup();
      
      /*===========================*/
      /* Create the buttons panel. */
      /*===========================*/

      JPanel buttonPanel = new JPanel(); 
      
      prevButton = new JButton(animalResources.getString("Prev"));
      prevButton.setActionCommand("Prev");
      buttonPanel.add(prevButton);
      prevButton.addActionListener(this);
      
      nextButton = new JButton(animalResources.getString("Next"));
      nextButton.setActionCommand("Next");
      buttonPanel.add(nextButton);
      nextButton.addActionListener(this);
     
      /*=====================================*/
      /* Add the panels to the content pane. */
      /*=====================================*/
      
      jfrm.getContentPane().add(displayPanel); 
      jfrm.getContentPane().add(choicesPanel); 
      jfrm.getContentPane().add(buttonPanel); 

      /*===================================*/
      /* Initialize the state information. */
      /*===================================*/

      variableAsserts = new ArrayList<String>();
      priorAnswers = new ArrayList<String>();

      /*==================================*/
      /* Load and run the animal program. */
      /*==================================*/

      clips = new Environment();
      
      try
        {
         clips.loadFromResource("/net/sf/clipsrules/jni/examples/animal/resources/bcengine.clp");
         clips.loadFromResource("/net/sf/clipsrules/jni/examples/animal/resources/animal.clp");
         
         try 
           {
            clips.loadFromResource("/net/sf/clipsrules/jni/examples/animal/resources/animal_" + 
                                   Locale.getDefault().getLanguage() + ".clp");
           }
         catch (FileNotFoundException fnfe)
           {
            if (Locale.getDefault().getLanguage().equals("en"))
              { throw fnfe; }
            else
              { clips.loadFromResource("/net/sf/clipsrules/jni/examples/animal/resources/animal_en.clp"); }
           }
            
         processRules();
        }
      catch (Exception e)
        {
         e.printStackTrace();
         System.exit(1);
        }

      /*====================*/
      /* Display the frame. */
      /*====================*/
      
      jfrm.setVisible(true);  
     }  

   /*******************/
   /* handleResponse: */
   /*******************/  
   private void handleResponse() throws Exception
     {
      /*===========================*/
      /* Get the current UI state. */
      /*===========================*/
            
      FactAddressValue fv = clips.findFact("UI-state");

      /*========================================*/
      /* Determine the Next/Prev button states. */
      /*========================================*/
      
      if (fv.getSlotValue("state").toString().equals("conclusion"))
        { 
         interviewState = InterviewState.CONCLUSION;
         nextButton.setActionCommand("Restart");
         nextButton.setText(animalResources.getString("Restart")); 
         prevButton.setVisible(true);
         choicesPanel.setVisible(false);
        }
      else if (fv.getSlotValue("state").toString().equals("greeting"))
        {
         interviewState = InterviewState.GREETING;
         nextButton.setActionCommand("Next");
         nextButton.setText(animalResources.getString("Next"));
         prevButton.setVisible(false);
         choicesPanel.setVisible(false);
        }
      else
        { 
         interviewState = InterviewState.INTERVIEW;
         nextButton.setActionCommand("Next");
         nextButton.setText(animalResources.getString("Next"));
         prevButton.setVisible(true);
         choicesPanel.setVisible(true);
        }
      
      /*=====================*/
      /* Set up the choices. */
      /*=====================*/
      
      choicesPanel.removeAll();
      choicesButtons = new ButtonGroup();
            
      MultifieldValue damf = (MultifieldValue) fv.getSlotValue("display-answers");
      MultifieldValue vamf = (MultifieldValue) fv.getSlotValue("valid-answers");
      
      String selected = fv.getSlotValue("response").toString();
      JRadioButton firstButton = null;
      
      for (int i = 0; i < damf.size(); i++) 
        {
         LexemeValue da = (LexemeValue) damf.get(i);
         LexemeValue va = (LexemeValue) vamf.get(i);
         JRadioButton rButton;
         String buttonName, buttonText, buttonAnswer;
         
         buttonName = da.getValue();
         buttonText = buttonName.substring(0,1).toUpperCase() + buttonName.substring(1);
         buttonAnswer = va.getValue();
         
         if (((lastAnswer != null) && buttonAnswer.equals(lastAnswer)) ||                  
             ((lastAnswer == null) && buttonAnswer.equals(selected)))
            { rButton = new JRadioButton(buttonText,true); }
         else
            { rButton = new JRadioButton(buttonText,false); }
         
         rButton.setActionCommand(buttonAnswer);
         choicesPanel.add(rButton);
         choicesButtons.add(rButton);
         
         if (firstButton == null)
           { firstButton = rButton; }
        }
        
      if ((choicesButtons.getSelection() == null) && (firstButton != null))
        { choicesButtons.setSelected(firstButton.getModel(),true); }

      choicesPanel.repaint();
      
      /*====================================*/
      /* Set the label to the display text. */
      /*====================================*/

      relationAsserted = ((LexemeValue) fv.getSlotValue("relation-asserted")).getValue();

      /*====================================*/
      /* Set the label to the display text. */
      /*====================================*/

      String theText = ((StringValue) fv.getSlotValue("display")).getValue();
            
      wrapLabelText(displayLabel,theText);
      
      executionThread = null;
      
      isExecuting = false;
     }

   /*########################*/
   /* ActionListener Methods */
   /*########################*/

   /*******************/
   /* actionPerformed */
   /*******************/  
   public void actionPerformed(
     ActionEvent ae)
     { 
      try
        { onActionPerformed(ae); }
      catch (Exception e)
        { e.printStackTrace(); }
     }

   /*************/
   /* runAnimal */
   /*************/  
   public void runAnimal()
     {
      Runnable runThread = 
         new Runnable()
           {
            public void run()
              {
               try
                 { clips.run(); }
               catch (CLIPSException e)
                 { e.printStackTrace(); }

               SwingUtilities.invokeLater(
                  new Runnable()
                    {
                     public void run()
                       {
                        try 
                          { handleResponse(); }
                        catch (Exception e)
                          { e.printStackTrace(); }
                       }
                    });
              }
           };
      
      isExecuting = true;
      
      executionThread = new Thread(runThread);
      
      executionThread.start();
     }

   /****************/
   /* processRules */
   /****************/  
   private void processRules() throws CLIPSException
     {
      clips.reset();      
      
      for (String factString : variableAsserts) 
        {
         String assertCommand = "(assert " + factString + ")";
         clips.eval(assertCommand);
		}
		
      runAnimal();
     }
     
   /********************/
   /* nextButtonAction */
   /********************/  
   private void nextButtonAction() throws CLIPSException
     { 
      String theString;
      String theAnswer;
      
      lastAnswer = null;
      switch (interviewState)
        {
         /* Handle Next button. */
         case GREETING:
         case INTERVIEW:
           theAnswer = choicesButtons.getSelection().getActionCommand();
           theString = "(variable (name " + relationAsserted + ") (value " +  theAnswer + "))";
           variableAsserts.add(theString);
           priorAnswers.add(theAnswer);
           break;
           
         /* Handle Restart button. */
         case CONCLUSION:
           variableAsserts.clear();
           priorAnswers.clear();
           break;
        }  
        
      processRules();      
     }

   /********************/
   /* prevButtonAction */
   /********************/  
   private void prevButtonAction() throws CLIPSException
     { 
      lastAnswer = priorAnswers.get(priorAnswers.size() - 1);
   
      variableAsserts.remove(variableAsserts.size() - 1);
      priorAnswers.remove(priorAnswers.size() - 1);
       
      processRules();   
     }

   /*********************/
   /* onActionPerformed */
   /*********************/  
   private void onActionPerformed(
     ActionEvent ae) throws Exception
     { 
      if (isExecuting) return;
      
      if (ae.getActionCommand().equals("Next"))
        { nextButtonAction(); }
      else if (ae.getActionCommand().equals("Restart"))
        { nextButtonAction(); }
      else if (ae.getActionCommand().equals("Prev"))
        { prevButtonAction(); }
     }

   /*****************/
   /* wrapLabelText */
   /*****************/  
   private void wrapLabelText(
     JLabel label, 
     String text) 
     {
      FontMetrics fm = label.getFontMetrics(label.getFont());
      Container container = label.getParent();
      int containerWidth = container.getWidth();
      int textWidth = SwingUtilities.computeStringWidth(fm,text);
      int desiredWidth;

      if (textWidth <= containerWidth)
        { desiredWidth = containerWidth; }
      else
        { 
         int lines = (int) ((textWidth + containerWidth) / containerWidth);
                  
         desiredWidth = (int) (textWidth / lines);
        }
                 
      BreakIterator boundary = BreakIterator.getWordInstance();
      boundary.setText(text);
   
      StringBuffer trial = new StringBuffer();
      StringBuffer real = new StringBuffer("<html><center>");
   
      int start = boundary.first();
      for (int end = boundary.next(); end != BreakIterator.DONE;
           start = end, end = boundary.next())
        {
         String word = text.substring(start,end);
         trial.append(word);
         int trialWidth = SwingUtilities.computeStringWidth(fm,trial.toString());
         if (trialWidth > containerWidth) 
           {
            trial = new StringBuffer(word);
            real.append("<br>");
            real.append(word);
           }
         else if (trialWidth > desiredWidth)
           {
            trial = new StringBuffer("");
            real.append(word);
            real.append("<br>");
           }
         else
           { real.append(word); }
        }
   
      real.append("</html>");
   
      label.setText(real.toString());
     }

   public static void main(String args[])
     {  
      // Create the frame on the event dispatching thread.  
      SwingUtilities.invokeLater(
        new Runnable() 
          {  
           public void run() { new AnimalDemo(); }  
          });   
     }  
  }