/**
 * Created on 11.10.2002
 * 
 * @author Jan Schulz
 */
package net.sourceforge.phpdt.tidy.preferences;

import java.util.ArrayList;
import java.util.List;

import org.eclipse.core.resources.IResource;
import org.eclipse.core.runtime.CoreException;
import org.eclipse.core.runtime.Platform;
import org.eclipse.core.runtime.QualifiedName;
import org.eclipse.jface.preference.IPreferenceStore;
import org.eclipse.jface.preference.PreferenceStore;
import org.eclipse.jface.resource.JFaceResources;
import org.eclipse.jface.util.Assert;
import org.eclipse.jface.util.IPropertyChangeListener;
import org.eclipse.jface.util.ListenerList;
import org.eclipse.jface.util.PropertyChangeEvent;
import org.eclipse.jface.util.SafeRunnable;


/**
 * This class can be used for wrapping a IResource to a PreferencePage
 * 
 * Most of the class is C&P from the PreferenceStore which uses a Propertie 
 * instance to store a the Properties.
 * 
 * 
 * @author Jan Schulz
 * @since 11.10.2002
 */
public class ResourcePreferenceStore implements IPreferenceStore {

	private IResource resource;
	private IPreferenceStore defaultValues = null;
	private String prefix;

	private List unDefaulted = new ArrayList();

	/** 
	 * List of registered listeners (element type: <code>IPropertyChangeListener</code>).
	 * These listeners are to be informed when the current value of a preference changes.
	 */
	private ListenerList listeners = new ListenerList();

	/**
	 * Indicates whether a value as been changed by <code>setToDefault</code>
	 * or <code>setValue</code>; initially <code>false</code>.
	 */
	private boolean dirty = false;

	/**
	 * <p>
	 * Creates a IPreferenceStore were the Values are stored in a IResource 
	 * and the defaultValues are taken from a different IPreferenceStore 
	 * (like the default one of the plugin). If _defaultValues is empty, no 
	 * default values are present.  
	 * </p>
	 * <p>
	 * Because of the different mechanism for storeing Preferences, any 
	 * lookup for a preference with the given name will be 'translated' as 
	 * following:
	 * </p><p>
	 * <ul>
	 * <li>The defaultValues are querried without prefix just with the given 
	 *     name</li>
	 * <li>The Resource will be querried with the prefix and the name as a  
	 *     QualifiedName</li>
	 * </ul> 
	 * </p><p>
	 * Be carefull: even defaulted Properties are written into the underlying 
	 * resource! 
	 * @param _prefix -- String used as Qualifier
	 * @param _resource -- a IResource, which may NOT be null
	 * @param _defaultValues -- a IPreferenceStore or null
		 */
	public ResourcePreferenceStore(IResource _resource, String _prefix, IPreferenceStore _defaultValues) {
		super();
		Assert.isNotNull(_resource);
		resource = _resource;
		prefix = _prefix;
		defaultValues = _defaultValues;
		if (defaultValues == null) {
			defaultValues = new PreferenceStore();
		}
	}

	public ResourcePreferenceStore(IResource _resource, String _prefix) {
		this(_resource, _prefix, null);
	}

	public ResourcePreferenceStore(IResource _resource) {
		this(_resource, null, null);
	}

	private QualifiedName getQNForName(String name) {
		return new QualifiedName(prefix, name);
	}

	private boolean resourceContains(String name) {
		try {
			return (resource.getPersistentProperty(getQNForName(name)) != null);
		} catch (CoreException e) {
			return false;
		}
	}

	private String getProperty(String name) {
		try {
			return resource.getPersistentProperty(getQNForName(name));
		} catch (CoreException e) {
		}

		return null;
	}

	private void setProperty(String name, String value) {
		try {
			resource.setPersistentProperty(getQNForName(name), value);
		} catch (CoreException e) {
		}

	}

	/* (non-Javadoc)
	 * Method declared on IPreferenceStore.
	 */
	public void addPropertyChangeListener(IPropertyChangeListener listener) {
		listeners.add(listener);
	}
	/* (non-Javadoc)
	 * Method declared on IPreferenceStore.
	 */
	public boolean contains(String name) {
		return (resourceContains(name) || defaultValues.contains(name));
	}
	/* (non-Javadoc)
	 * Method declared on IPreferenceStore.
	 */
	public void firePropertyChangeEvent(String name, Object oldValue, Object newValue) {
		final Object[] listeners = this.listeners.getListeners();
		// Do we need to fire an event.
		if (listeners.length > 0 && (oldValue == null || !oldValue.equals(newValue))) {
			final PropertyChangeEvent pe = new PropertyChangeEvent(this, name, oldValue, newValue);

			Platform.run(new SafeRunnable(JFaceResources.getString("PreferenceStore.changeError")) { //$NON-NLS-1$
				public void run() {
					for (int i = 0; i < listeners.length; ++i) {
						IPropertyChangeListener l = (IPropertyChangeListener) listeners[i];
						l.propertyChange(pe);
					}
				}
			});
		}
	}

	/**
	 * Helper function: gets boolean for a given name.
	 */
	public boolean getBoolean(String name) {
		String value = getProperty(name);
		if (value == null)
			return BOOLEAN_DEFAULT_DEFAULT;
		if (value.equals(IPreferenceStore.TRUE))
			return true;
		return false;
	}
	/* (non-Javadoc)
	 * Method declared on IPreferenceStore.
	 */
	public boolean getDefaultBoolean(String name) {
		return defaultValues.getBoolean(name);
	}
	/* (non-Javadoc)
	 * Method declared on IPreferenceStore.
	 */
	public double getDefaultDouble(String name) {
		return defaultValues.getDouble(name);
	}
	/* (non-Javadoc)
	 * Method declared on IPreferenceStore.
	 */
	public float getDefaultFloat(String name) {
		return defaultValues.getFloat(name);
	}
	/* (non-Javadoc)
	 * Method declared on IPreferenceStore.
	 */
	public int getDefaultInt(String name) {
		return defaultValues.getInt(name);
	}
	/* (non-Javadoc)
	 * Method declared on IPreferenceStore.
	 */
	public long getDefaultLong(String name) {
		return defaultValues.getLong(name);
	}
	/* (non-Javadoc)
	 * Method declared on IPreferenceStore.
	 */
	public String getDefaultString(String name) {
		return defaultValues.getString(name);
	}

	public double getDouble(String name) {
		String value = getProperty(name);
		if (value == null)
			return DOUBLE_DEFAULT_DEFAULT;
		double ival = DOUBLE_DEFAULT_DEFAULT;
		try {
			ival = new Double(value).doubleValue();
		} catch (NumberFormatException e) {
		}
		return ival;
	}

	/**
	* Helper function: gets long for a given name.
	*/
	public long getLong(String name) {
		String value = getProperty(name);
		if (value == null)
			return LONG_DEFAULT_DEFAULT;
		long ival = LONG_DEFAULT_DEFAULT;
		try {
			ival = Long.parseLong(value);
		} catch (NumberFormatException e) {
		}
		return ival;
	}
	/* (non-Javadoc)
	 * Method declared on IPreferenceStore.
	 */
	public String getString(String name) {
		String value = getProperty(name);
		if (value == null)
			return STRING_DEFAULT_DEFAULT;
		return value;
	}

	public float getFloat(String name) {
		String value = getProperty(name);
		if (value == null)
			return FLOAT_DEFAULT_DEFAULT;
		float ival = FLOAT_DEFAULT_DEFAULT;
		try {
			ival = new Float(value).floatValue();
		} catch (NumberFormatException e) {
		}
		return ival;
	}

	/* (non-Javadoc)
	 * Method declared on IPreferenceStore.
	 */

	public int getInt(String name) {
		String value = getProperty(name);
		if (value == null)
			return INT_DEFAULT_DEFAULT;
		int ival = 0;
		try {
			ival = Integer.parseInt(value);
		} catch (NumberFormatException e) {
		}
		return ival;
	}

	/* (non-Javadoc)
	 * Method declared on IPreferenceStore.
	 */
	public boolean isDefault(String name) {
		//REMIND: Is that the right algo?
		return (!resourceContains(name) || getProperty(name).equals(defaultValues.getString(name)));
	}

	/**
	 * Indicates whether this PrefStore needds saving. As there isn't any saving 
	 * facility, it always returns false
	 * 
	 * Method declared on IPreferenceStore.
	 */
	public boolean needsSaving() {
		return false;
	}

	/* (non-Javadoc)
	 * Method declared on IPreferenceStore.
	 */
	public void putValue(String name, String value) {
		String oldValue = getString(name);
		if (oldValue == null || !oldValue.equals(value)) {
			setValue(name, value);
			dirty = true;

		}
	}
	/* (non-Javadoc)
	 * Method declared on IPreferenceStore.
	 */
	public void removePropertyChangeListener(IPropertyChangeListener listener) {
		listeners.remove(listener);
	}

	/* (non-Javadoc)
	 * Method declared on IPreferenceStore.
	 */
	public void setDefault(String name, double value) {
		defaultValues.setValue(name, value);
	}
	/* (non-Javadoc)
	 * Method declared on IPreferenceStore.
	 */
	public void setDefault(String name, float value) {
		defaultValues.setValue(name, value);
	}
	/* (non-Javadoc)
	 * Method declared on IPreferenceStore.
	 */
	public void setDefault(String name, int value) {
		defaultValues.setValue(name, value);
	}
	/* (non-Javadoc)
	 * Method declared on IPreferenceStore.
	 */
	public void setDefault(String name, long value) {
		defaultValues.setValue(name, value);
	}
	/* (non-Javadoc)
	 * Method declared on IPreferenceStore.
	 */
	public void setDefault(String name, String value) {
		defaultValues.setValue(name, value);
	}
	/* (non-Javadoc)
	 * Method declared on IPreferenceStore.
	 */
	public void setDefault(String name, boolean value) {
		defaultValues.setValue(name, value);
	}

	/* (non-Javadoc)
	 * Method declared on IPreferenceStore.
	 */
	public void setToDefault(String name) {
		Object oldValue = getProperty(name);
		String newValue = null;
		if (defaultValues != null)
			newValue = (String) defaultValues.getString(name);
		setProperty(name, newValue);
		dirty = true;

		firePropertyChangeEvent(name, oldValue, newValue);
	}
	/* (non-Javadoc)
	 * Method declared on IPreferenceStore.
	 */
	public void setValue(String name, double value) {
		double oldValue = getDouble(name);
		if (oldValue != value) {
			setProperty(name, Double.toString(value));
			dirty = true;
			firePropertyChangeEvent(name, new Double(oldValue), new Double(value));
		}
	}
	/* (non-Javadoc)
	 * Method declared on IPreferenceStore.
	 */
	public void setValue(String name, float value) {
		float oldValue = getFloat(name);
		if (oldValue != value) {
			setProperty(name, Float.toString(value));
			dirty = true;
			firePropertyChangeEvent(name, new Float(oldValue), new Float(value));
		}
	}
	/* (non-Javadoc)
	 * Method declared on IPreferenceStore.
	 */
	public void setValue(String name, int value) {
		int oldValue = getInt(name);
		if (oldValue != value) {
			setProperty(name, Integer.toString(value));
			dirty = true;
			firePropertyChangeEvent(name, new Integer(oldValue), new Integer(value));
		}
	}
	/* (non-Javadoc)
	 * Method declared on IPreferenceStore.
	 */
	public void setValue(String name, long value) {
		long oldValue = getLong(name);
		if (oldValue != value) {
			setProperty(name, Long.toString(value));
			dirty = true;
			firePropertyChangeEvent(name, new Long(oldValue), new Long(value));
		}
	}
	/* (non-Javadoc)
	 * Method declared on IPreferenceStore.
	 */
	public void setValue(String name, String value) {
		String oldValue = getString(name);
		if (oldValue == null || !oldValue.equals(value)) {
			setProperty(name, value);
			dirty = true;
			firePropertyChangeEvent(name, oldValue, value);
		}
	}
	/* (non-Javadoc)
	 * Method declared on IPreferenceStore.
	 */
	public void setValue(String name, boolean value) {
		boolean oldValue = getBoolean(name);
		if (oldValue != value) {
			setProperty(name, value == true ? IPreferenceStore.TRUE : IPreferenceStore.FALSE);
			dirty = true;
			firePropertyChangeEvent(name, new Boolean(oldValue), new Boolean(value));
		}
	}

}