package com.onaro.util.jfc.mixedvalue;

import javax.swing.*;
import java.awt.*;
import java.awt.event.FocusEvent;
import java.awt.event.FocusListener;

/**
 * Shows "Mixed values" when the value is null
 */
public class MixedValueTextArea extends JTextArea implements FocusListener{
    private static final long serialVersionUID = 1L;
    
    private String mixedValueText;
    private Color regularColor;
    private Font italicFont;
    private Font plainFont;

    public MixedValueTextArea(String mixedValueText, int rows, int columns) {
        super(rows,columns);
        this.mixedValueText = mixedValueText;
        this.regularColor = this.getForeground();
        italicFont = getFont().deriveFont(Font.ITALIC);
        plainFont = getFont().deriveFont(Font.PLAIN);

        setMixed();
        addFocusListener(this);
    }

    private void setMixed() {
        super.setText(mixedValueText);
        setForeground(UIManager.getColor("mixedValue.color")); //$NON-NLS-1$
        setFont(italicFont);
    }

    public void focusGained(FocusEvent e) {
        if (mixedValueText.equals(super.getText()) && isFocusOwner()) {
            setText(null);
        }
    }

    public void focusLost(FocusEvent e) {
        //do nothing
    }

    public String getText() {
        String text = super.getText();
        return text.equals(mixedValueText) ? null : text;
    }

    public void setText(String text){
        if(text == null){
            text = mixedValueText;
            setMixed();
        }else{
            setNormal();
        }
        super.setText(text);
    }

    private void setNormal() {
        setForeground(regularColor);
        setFont(plainFont);
    }
}