content: /*******************************************************************************
   * Copyright (c) 2000, 2008 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
   *******************************************************************************/
   
  package org.eclipse.wst.jsdt.internal.ui.preferences;
  
  import org.eclipse.core.runtime.Assert;
  import org.eclipse.jface.preference.IPreferenceStore;
  import org.eclipse.jface.preference.PreferenceStore;
  import org.eclipse.jface.util.IPropertyChangeListener;
  import org.eclipse.jface.util.PropertyChangeEvent;
  
  
  /**
   * An overlaying preference store.
   */
  public class OverlayPreferenceStore  implements IPreferenceStore {
  	
  	
  	public static final class TypeDescriptor {
  		private TypeDescriptor() {
  		}
  	}
  	
  	public static final TypeDescriptor BOOLEAN= new TypeDescriptor();
  	public static final TypeDescriptor DOUBLE= new TypeDescriptor();
  	public static final TypeDescriptor FLOAT= new TypeDescriptor();
  	public static final TypeDescriptor INT= new TypeDescriptor();
  	public static final TypeDescriptor LONG= new TypeDescriptor();
  	public static final TypeDescriptor STRING= new TypeDescriptor();
  	
  	public static class OverlayKey {
  		
  		TypeDescriptor fDescriptor;
  		String fKey;
  		
  		public OverlayKey(TypeDescriptor descriptor, String key) {
  			fDescriptor= descriptor;
  			fKey= key;
  		}
  	}
  	
  	private class PropertyListener implements IPropertyChangeListener {
  				
  		/*
  		 * @see IPropertyChangeListener#propertyChange(PropertyChangeEvent)
  		 */
  		public void propertyChange(PropertyChangeEvent event) {
  			OverlayKey key= findOverlayKey(event.getProperty());
  			if (key != null)
  				propagateProperty(fParent, key, fStore); 
  		}
  	}
  	
  	
  	private IPreferenceStore fParent;
  	private IPreferenceStore fStore;
  	private OverlayKey[] fOverlayKeys;
  	
  	private PropertyListener fPropertyListener;
  	private boolean fLoaded;
  	
  	
  	public OverlayPreferenceStore(IPreferenceStore parent, OverlayKey[] overlayKeys) {
  		fParent= parent;
  		fOverlayKeys= overlayKeys;
  		fStore= new PreferenceStore();
  	}
  	
  	private OverlayKey findOverlayKey(String key) {
  		for (int i= 0; i < fOverlayKeys.length; i++) {
  			if (fOverlayKeys[i].fKey.equals(key))
  				return fOverlayKeys[i];
  		}
  		return null;
  	}
  	
  	private boolean covers(String key) {
  		return (findOverlayKey(key) != null);
  	}
  	
  	private void propagateProperty(IPreferenceStore orgin, OverlayKey key, IPreferenceStore target) {
  		
  		if (orgin.isDefault(key.fKey)) {
  			if (!target.isDefault(key.fKey))
  				target.setToDefault(key.fKey);
  			return;
  		}
  		
  		TypeDescriptor d= key.fDescriptor;
  		if (BOOLEAN == d) {
  			
  			boolean originValue= orgin.getBoolean(key.fKey);
  			boolean targetValue= target.getBoolean(key.fKey);
  			if (targetValue != originValue)
  				target.setValue(key.fKey, originValue);
  				
  		} else if (DOUBLE == d) {
  			
  			double originValue= orgin.getDouble(key.fKey);
  			double targetValue= target.getDouble(key.fKey);
  			if (targetValue != originValue)
  				target.setValue(key.fKey, originValue);
  		
  		} else if (FLOAT == d) {
  			
  			float originValue= orgin.getFloat(key.fKey);
  			float targetValue= target.getFloat(key.fKey);
  			if (targetValue != originValue)
  				target.setValue(key.fKey, originValue);
  				
  		} else if (INT == d) {
  
  			int originValue= orgin.getInt(key.fKey);
  			int targetValue= target.getInt(key.fKey);
  			if (targetValue != originValue)
  				target.setValue(key.fKey, originValue);
  
  		} else if (LONG == d) {
  
  			long originValue= orgin.getLong(key.fKey);
  			long targetValue= target.getLong(key.fKey);
  			if (targetValue != originValue)
  				target.setValue(key.fKey, originValue);
  
  		} else if (STRING == d) {
  
  			String originValue= orgin.getString(key.fKey);
  			String targetValue= target.getString(key.fKey);
  			if (targetValue != null && originValue != null && !targetValue.equals(originValue))
  				target.setValue(key.fKey, originValue);
  
  		}
  	}
  	
  	public void propagate() {
  		for (int i= 0; i < fOverlayKeys.length; i++)
  			propagateProperty(fStore, fOverlayKeys[i], fParent);
  	}
  	
  	private void loadProperty(IPreferenceStore orgin, OverlayKey key, IPreferenceStore target, boolean forceInitialization) {
  		TypeDescriptor d= key.fDescriptor;
  		if (BOOLEAN == d) {
  			
  			if (forceInitialization)
  				target.setValue(key.fKey, true);
  			target.setValue(key.fKey, orgin.getBoolean(key.fKey));
  			target.setDefault(key.fKey, orgin.getDefaultBoolean(key.fKey));
  			
  		} else if (DOUBLE == d) {
  			
  			if (forceInitialization)
  				target.setValue(key.fKey, 1.0D);
  			target.setValue(key.fKey, orgin.getDouble(key.fKey));
  			target.setDefault(key.fKey, orgin.getDefaultDouble(key.fKey));
  			
  		} else if (FLOAT == d) {
  			
  			if (forceInitialization)
  				target.setValue(key.fKey, 1.0F);
  			target.setValue(key.fKey, orgin.getFloat(key.fKey));
  			target.setDefault(key.fKey, orgin.getDefaultFloat(key.fKey));
  			
  		} else if (INT == d) {
  			
  			if (forceInitialization)
  				target.setValue(key.fKey, 1);
  			target.setValue(key.fKey, orgin.getInt(key.fKey));
  			target.setDefault(key.fKey, orgin.getDefaultInt(key.fKey));
  			
  		} else if (LONG == d) {
  			
  			if (forceInitialization)
  				target.setValue(key.fKey, 1L);
  			target.setValue(key.fKey, orgin.getLong(key.fKey));
  			target.setDefault(key.fKey, orgin.getDefaultLong(key.fKey));
  			
  		} else if (STRING == d) {
  			
  			if (forceInitialization)
  				target.setValue(key.fKey, "1"); //$NON-NLS-1$
  			target.setValue(key.fKey, orgin.getString(key.fKey));
  			target.setDefault(key.fKey, orgin.getDefaultString(key.fKey));
  			
  		}
  	}
  	
  	public void load() {
  		for (int i= 0; i < fOverlayKeys.length; i++)
  			loadProperty(fParent, fOverlayKeys[i], fStore, true);
  		
  		fLoaded= true;
  		
  	}
  	
  	public void loadDefaults() {
  		for (int i= 0; i < fOverlayKeys.length; i++)
  			setToDefault(fOverlayKeys[i].fKey);
  	}
  	
  	public void start() {
  		if (fPropertyListener == null) {
  			fPropertyListener= new PropertyListener();
  			fParent.addPropertyChangeListener(fPropertyListener);
  		}
  	}
  	
  	public void stop() {
  		if (fPropertyListener != null)  {
  			fParent.removePropertyChangeListener(fPropertyListener);
  			fPropertyListener= null;
  		}
  	}
  	
  	/*
  	 * @see IPreferenceStore#addPropertyChangeListener(IPropertyChangeListener)
  	 */
  	public void addPropertyChangeListener(IPropertyChangeListener listener) {
  		fStore.addPropertyChangeListener(listener);
  	}
  	
  	/*
  	 * @see IPreferenceStore#removePropertyChangeListener(IPropertyChangeListener)
  	 */
  	public void removePropertyChangeListener(IPropertyChangeListener listener) {
  		fStore.removePropertyChangeListener(listener);
  	}
  	
  	/*
  	 * @see IPreferenceStore#firePropertyChangeEvent(String, Object, Object)
  	 */
  	public void firePropertyChangeEvent(String name, Object oldValue, Object newValue) {
  		fStore.firePropertyChangeEvent(name, oldValue, newValue);
  	}
  
  	/*
  	 * @see IPreferenceStore#contains(String)
  	 */
  	public boolean contains(String name) {
  		return fStore.contains(name);
  	}
  	
  	/*
  	 * @see IPreferenceStore#getBoolean(String)
  	 */
  	public boolean getBoolean(String name) {
  		return fStore.getBoolean(name);
  	}
  
  	/*
  	 * @see IPreferenceStore#getDefaultBoolean(String)
  	 */
  	public boolean getDefaultBoolean(String name) {
  		return fStore.getDefaultBoolean(name);
  	}
  
  	/*
  	 * @see IPreferenceStore#getDefaultDouble(String)
  	 */
  	public double getDefaultDouble(String name) {
  		return fStore.getDefaultDouble(name);
  	}
  
  	/*
  	 * @see IPreferenceStore#getDefaultFloat(String)
  	 */
  	public float getDefaultFloat(String name) {
  		return fStore.getDefaultFloat(name);
  	}
  
  	/*
  	 * @see IPreferenceStore#getDefaultInt(String)
  	 */
  	public int getDefaultInt(String name) {
  		return fStore.getDefaultInt(name);
  	}
  
  	/*
  	 * @see IPreferenceStore#getDefaultLong(String)
  	 */
  	public long getDefaultLong(String name) {
  		return fStore.getDefaultLong(name);
  	}
  
  	/*
  	 * @see IPreferenceStore#getDefaultString(String)
  	 */
  	public String getDefaultString(String name) {
  		return fStore.getDefaultString(name);
  	}
  
  	/*
  	 * @see IPreferenceStore#getDouble(String)
  	 */
  	public double getDouble(String name) {
  		return fStore.getDouble(name);
  	}
  
  	/*
  	 * @see IPreferenceStore#getFloat(String)
  	 */
  	public float getFloat(String name) {
  		return fStore.getFloat(name);
  	}
  
  	/*
  	 * @see IPreferenceStore#getInt(String)
  	 */
  	public int getInt(String name) {
  		return fStore.getInt(name);
  	}
  
  	/*
  	 * @see IPreferenceStore#getLong(String)
  	 */
  	public long getLong(String name) {
  		return fStore.getLong(name);
  	}
  
  	/*
  	 * @see IPreferenceStore#getString(String)
  	 */
  	public String getString(String name) {
  		return fStore.getString(name);
  	}
  
  	/*
  	 * @see IPreferenceStore#isDefault(String)
  	 */
  	public boolean isDefault(String name) {
  		return fStore.isDefault(name);
  	}
  
  	/*
  	 * @see IPreferenceStore#needsSaving()
  	 */
  	public boolean needsSaving() {
  		return fStore.needsSaving();
  	}
  
  	/*
  	 * @see IPreferenceStore#putValue(String, String)
  	 */
  	public void putValue(String name, String value) {
  		if (covers(name))
  			fStore.putValue(name, value);
  	}
  
  	/*
  	 * @see IPreferenceStore#setDefault(String, double)
  	 */
  	public void setDefault(String name, double value) {
  		if (covers(name))
  			fStore.setDefault(name, value);
  	}
  
  	/*
  	 * @see IPreferenceStore#setDefault(String, float)
  	 */
  	public void setDefault(String name, float value) {
  		if (covers(name))
  			fStore.setDefault(name, value);
  	}
  
  	/*
  	 * @see IPreferenceStore#setDefault(String, int)
  	 */
  	public void setDefault(String name, int value) {
  		if (covers(name))
  			fStore.setDefault(name, value);
  	}
  
  	/*
  	 * @see IPreferenceStore#setDefault(String, long)
  	 */
  	public void setDefault(String name, long value) {
  		if (covers(name))
  			fStore.setDefault(name, value);
  	}
  
  	/*
  	 * @see IPreferenceStore#setDefault(String, String)
  	 */
  	public void setDefault(String name, String value) {
  		if (covers(name))
  			fStore.setDefault(name, value);
  	}
  
  	/*
  	 * @see IPreferenceStore#setDefault(String, boolean)
  	 */
  	public void setDefault(String name, boolean value) {
  		if (covers(name))
  			fStore.setDefault(name, value);
  	}
  
  	/*
  	 * @see IPreferenceStore#setToDefault(String)
  	 */
  	public void setToDefault(String name) {
  		fStore.setToDefault(name);
  	}
  
  	/*
  	 * @see IPreferenceStore#setValue(String, double)
  	 */
  	public void setValue(String name, double value) {
  		if (covers(name))
  			fStore.setValue(name, value);
  	}
  
  	/*
  	 * @see IPreferenceStore#setValue(String, float)
  	 */
  	public void setValue(String name, float value) {
  		if (covers(name))
  			fStore.setValue(name, value);
  	}
  
  	/*
  	 * @see IPreferenceStore#setValue(String, int)
  	 */
  	public void setValue(String name, int value) {
  		if (covers(name))
  			fStore.setValue(name, value);
  	}
  
  	/*
  	 * @see IPreferenceStore#setValue(String, long)
  	 */
  	public void setValue(String name, long value) {
  		if (covers(name))
  			fStore.setValue(name, value);
  	}
  
  	/*
  	 * @see IPreferenceStore#setValue(String, String)
  	 */
  	public void setValue(String name, String value) {
  		if (covers(name))
  			fStore.setValue(name, value);
  	}
  
  	/*
  	 * @see IPreferenceStore#setValue(String, boolean)
  	 */
  	public void setValue(String name, boolean value) {
  		if (covers(name))
  			fStore.setValue(name, value);
  	}
  
  	/**
  	 * The keys to add to the list of overlay keys.
  	 * <p>
  	 * Note: This method must be called before {@link #load()} is called. 
  	 * </p>
  	 * 
  	 * @param keys
  	 * 
  	 */
  	public void addKeys(OverlayKey[] keys) {
  		Assert.isTrue(!fLoaded);
  		Assert.isNotNull(keys);
  		
  		int overlayKeysLength= fOverlayKeys.length;
  		OverlayKey[] result= new OverlayKey[keys.length + overlayKeysLength];
  
  		for (int i= 0, length= overlayKeysLength; i < length; i++)
  			result[i]= fOverlayKeys[i];
  		
  		for (int i= 0, length= keys.length; i < length; i++)
  			result[overlayKeysLength + i]= keys[i];
  		
  		fOverlayKeys= result;
  		
  		if (fLoaded)
  			load();
  	}
  }
  