/*******************************************************************************
 * Copyright (c) 2000, 2005 IBM Corporation and others.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     IBM Corporation - initial API and implementation
 * Port to the D programming language:
 *     Frank Benoit <benoit@tionex.de>
 *******************************************************************************/
module dwtx.draw2d.DefaultRangeModel;

import dwt.dwthelper.utils;
import dwtx.dwtxhelper.Bean;
import tango.text.convert.Format;

import dwtx.draw2d.RangeModel;

/**
 * Generic implementation for a RangeModel.
 *
 *
 *<pre>
 *                    |<----extent--->|
 *    ----|-----------|---------------|---------------|----
 *       min          |                              max
 *                  value
 * </pre>
 */
public class DefaultRangeModel
    : RangeModel
{

/**
 * Listeners interested in the range model's property changes.
 */
protected PropertyChangeSupport propertyListeners;
private int minimum = 0;
private int maximum = 100;
private int extent =  20;
private int value = 0;

public this(){
    propertyListeners = new PropertyChangeSupport(this);
}

/**
 * Registers the given listener as a PropertyChangeListener.
 *
 * @param listener the listener to be added
 * @since 2.0
 */
public void addPropertyChangeListener(PropertyChangeListener listener) {
    propertyListeners.addPropertyChangeListener(listener);
}

/**
 * Notifies any listening PropertyChangeListeners that the property with the given id has
 * changed.
 *
 * @param string the property name
 * @param oldValue the old value
 * @param newValue the new value
 * @since 2.0
 */
protected void firePropertyChange(String string, int oldValue, int newValue) {
    propertyListeners.firePropertyChange(string, oldValue, newValue);
}

/**
 * @return the extent
 */
public int getExtent() {
    return extent;
}

/**
 * @return the maximum value
 */
public int getMaximum() {
    return maximum;
}

/**
 * @return the minimum value
 */
public int getMinimum() {
    return minimum;
}

/**
 * @return the current value
 */
public int getValue() {
    return value;
}

/**
 * @return whether the extent is between the minimum and maximum values
 */
public bool isEnabled() {
    return (getMaximum() - getMinimum()) > getExtent();
}

/**
 * Removes the given PropertyChangeListener from the list of listeners.
 *
 * @param listener the listener to be removed
 */
public void removePropertyChangeListener(PropertyChangeListener listener) {
    propertyListeners.removePropertyChangeListener(listener);
}

/**
 * @see dwtx.draw2d.RangeModel#setAll(int, int, int)
 */
public void setAll(int min, int ext, int max) {
    int oldMin = minimum;
    int oldExtent = extent;
    int oldMax = maximum;
    maximum = max;
    minimum = min;
    extent = ext;
    if (oldMax !is max)
        firePropertyChange(PROPERTY_MAXIMUM, oldMax, max);
    if (oldExtent !is ext)
        firePropertyChange(PROPERTY_EXTENT, oldExtent, ext);
    if (oldMin !is min)
        firePropertyChange(PROPERTY_MINIMUM, oldMin, min);
    setValue(getValue());
}

/**
 * Sets this RangeModel's extent and fires a property change if the given value is
 * different from the current extent.
 *
 * @param extent the new extent value
 */
public void setExtent(int extent) {
    if (this.extent is extent)
        return;
    int oldValue = this.extent;
    this.extent = extent;
    firePropertyChange(PROPERTY_EXTENT, oldValue, extent);
    setValue(getValue());
}

/**
 * Sets this RangeModel's maximum value and fires a property change if the given value is
 * different from the current maximum value.
 *
 * @param maximum the new maximum value
 */
public void setMaximum(int maximum) {
    if (this.maximum is maximum)
        return;
    int oldValue = this.maximum;
    this.maximum = maximum;
    firePropertyChange(PROPERTY_MAXIMUM, oldValue, maximum);
    setValue(getValue());
}

/**
 * Sets this RangeModel's minimum value and fires a property change if the given value is
 * different from the current minimum value.
 *
 * @param minimum the new minumum value
 */
public void setMinimum(int minimum) {
    if (this.minimum is minimum)
        return;
    int oldValue = this.minimum;
    this.minimum = minimum;
    firePropertyChange(PROPERTY_MINIMUM, oldValue, minimum);
    setValue(getValue());
}

/**
 * Sets this RangeModel's current value.  If the given value is greater than the maximum,
 * the maximum value is used.  If the given value is less than the minimum, the minimum
 * value is used.  If the adjusted value is different from the current value, a property
 * change is fired.
 *
 * @param value the new value
 */
public void setValue(int value) {
    value = Math.max(getMinimum(), Math.min(getMaximum() - getExtent(), value));
    if (this.value is value)
        return;
    int oldValue = this.value;
    this.value = value;
    firePropertyChange(PROPERTY_VALUE, oldValue, value);
}

/**
 * @see java.lang.Object#toString()
 */
public String toString() {
    return Format( "{} ({}, {}, {}, {})", super.toString(), minimum, maximum //$NON-NLS-2$ //$NON-NLS-1$
            , extent, value ); //$NON-NLS-3$ //$NON-NLS-2$ //$NON-NLS-1$
}

}