/**

  * Copyright 2009 Timothy Johnston Licensed under the Apache License, Version 2.0 (the "License"); you may not use this

  * file except in compliance with the License. You may obtain a copy of the License at

  * 

  * http://www.apache.org/licenses/LICENSE-2.0

  * 

  * Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on

  * an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the

  * specific language governing permissions and limitations under the License.

  */

 package com.timjohnstondev.unitconverter.view;

 import java.awt.Color;

 import java.awt.Component;

 import java.awt.Dimension;

 import java.awt.GridLayout;

 import java.awt.event.KeyAdapter;

 import java.awt.event.KeyEvent;

 import java.math.BigDecimal;

 import java.util.ResourceBundle;

 import javax.swing.BorderFactory;

 import javax.swing.JLabel;

 import javax.swing.JPanel;

 import javax.swing.JTextField;

 import javax.swing.event.DocumentEvent;

 import javax.swing.event.DocumentListener;

 import com.timjohnstondev.unitconverter.controller.LogicController;

 /**

  * This panel contains all of the {@code JTextField}s for input, conversion factor and result display. All fields can be

  * copied from, but only the input field can take number input.

  */

 public class CalculationPanel extends JPanel implements Configuration

 {

   private LogicController logicController;

   private JLabel inputLabel;

   private JLabel conversionFactorLabel;

   private JLabel resultLabel;

   private JTextField input;

   private ConversionTextField conversionFactor;

   private JTextField result;

   private ResourceBundle resources;

   /**

    * Constructs a {@code CalculationPanel} and sets the layout and size of the panel and its contents.

    */

   public CalculationPanel()

   {

     setMaximumSize(new Dimension(500, 80));

     setLayout(new GridLayout(2, 3, 10, 5));

     setBorder(BorderFactory.createEmptyBorder(20, 10, 5, 10));

     logicController = new LogicController();

     resources = ResourceBundle.getBundle("com.timjohnstondev.unitconverter.view.View");

     inputLabel = new JLabel(resources.getString("CalculationPanel.inputLabel"));

     conversionFactorLabel = new JLabel(resources.getString("CalculationPanel.conversionFactorLabel"));

     resultLabel = new JLabel(resources.getString("CalculationPanel.resultLabel"));

     configureLabels();

     input = new JTextField();

     input.setDocument(new InputFilter(resources.getString("CalculationPanel.allowableCharacters")));

     conversionFactor = new ConversionTextField();

     result = new JTextField();

     addListeners();

     add(inputLabel);

     add(conversionFactorLabel);

     add(resultLabel);

     add(input);

     add(conversionFactor);

     add(result);

   }

   /**

    * Updates the conversion factor field and stores the exact number or formula because the display may limit the

    * characters to show.

    * 

    * @param conversion the conversion factor or formula

    */

   public final void setConversion(final String conversion)

   {

     conversionFactor.setConversion(conversion);

     final String text = logicController.getConversionFactor(conversion);

     conversionFactor.setText(text);

   }

   /**

    * Updates the result field if the input field has valid data and a conversion factor is selected.

    * 

    * @param molecularWeightCorrection the correction factor to adjust for molecular weight in mole to mass and mass to

    *          mole conversions

    */

   public final void updateCalculations(final BigDecimal molecularWeightCorrection)

   {

     final String conversion = conversionFactor.getConversion();

     final String resultText = logicController.getResult(input.getText(), conversion, molecularWeightCorrection);

     result.setText(resultText);

   }

   private void updateCalculations()

   {

     updateCalculations(BigDecimal.ONE);

   }

   /**

    * Clears out the text of the conversion factor and results displays by setting their text to {@code null}.

    */

   public final void clearFactor()

   {

     conversionFactor.setConversion(null);

     conversionFactor.setText(null);

     result.setText(null);

   }

   private void configureLabels()

   {

     final JLabel[] labels = {inputLabel, conversionFactorLabel, resultLabel};

     for (JLabel label : labels)

     {

       label.setBorder(BorderFactory.createEmptyBorder(0, 0, 0, 0));

     }

   }

   private void addListeners()

   {

     input.getDocument().addDocumentListener(new InputDocumentListener());

     conversionFactor.addKeyListener(new DoNothingKeyListener());

     result.addKeyListener(new DoNothingKeyListener());

   }

   private class InputDocumentListener implements DocumentListener

   {

     @Override

     public final void changedUpdate(final DocumentEvent e)

     {

       updateCalculations();

     }

     @Override

     public final void insertUpdate(final DocumentEvent e)

     {

       changedUpdate(e);

     }

     @Override

     public final void removeUpdate(final DocumentEvent e)

     {

       changedUpdate(e);

     }

   }

   private class DoNothingKeyListener extends KeyAdapter

   {

     @Override

     public final void keyPressed(final KeyEvent e)

     {

       if (e.getKeyCode() == KeyEvent.VK_V)

       {

         e.consume();

       }

     }

     @Override

     public final void keyTyped(final KeyEvent e)

     {

       e.consume();

     }

   }

   private class ConversionTextField extends JTextField

   {

     private String conversion;

     private void setConversion(final String newConversion)

     {

       conversion = newConversion;

     }

     private String getConversion()

     {

       return conversion;

     }

   }

   @Override

   public final void setBackgroundColor(final Color color)

   {

     setBackground(color);

     final Component[] children = getComponents();

     for (Component child : children)

     {

       if (child instanceof JLabel)

       {

         child.setBackground(color);

       }

       if (child instanceof JTextField)

       {

         child.setBackground(color.brighter());

       }

     }

   }

   @Override

   public final void setForegroundColor(final Color color)

   {

     setForeground(color);

     final Component[] children = getComponents();

     for (Component child : children)

     {

       child.setForeground(color);

     }

   }

   @Override

   public final void setFontSize(final float fontSize)

   {

     setFont(getFont().deriveFont(fontSize));

     final Component[] children = getComponents();

     for (Component child : children)

     {

       child.setFont(child.getFont().deriveFont(fontSize));

     }

   }

 }