/*******************************************************************************
 * Copyright (c) 2000, 2003 IBM Corporation and others.
 * All rights reserved. This program and the accompanying materials 
 * are made available under the terms of the Common Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/cpl-v10.html
 * 
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/
package org.eclipse.ui.views.properties;

import java.io.File;

import org.eclipse.core.resources.IFile;
import org.eclipse.core.resources.IResource;
import org.eclipse.core.runtime.IPath;

/**
 * The FilePropertySource gives the extra information that is shown for files
 */
public class FilePropertySource extends ResourcePropertySource {

	private static PropertyDescriptor fileDescriptor;
	{
		fileDescriptor =
			new PropertyDescriptor(
				IResourcePropertyConstants.P_SIZE_RES,
				IResourcePropertyConstants.P_DISPLAY_SIZE);
		fileDescriptor.setAlwaysIncompatible(true);
		fileDescriptor.setCategory(IResourcePropertyConstants.P_FILE_SYSTEM_CATEGORY);
	}	
/**
 * Creates an property source for a file resource.
 * @param file the file resource
 */
public FilePropertySource(IFile file) {
	super(file);
}
/**
 * Get a PropertyDescriptor that defines the size property
 * @return the PropertyDescriptor
 */
private static PropertyDescriptor getInitialPropertyDescriptor() {
	return fileDescriptor;
}
/* (non-Javadoc)
 * Method declared on IPropertySource.
 */
public IPropertyDescriptor[] getPropertyDescriptors() {
	IPropertyDescriptor[] superDescriptors = super.getPropertyDescriptors();
	int superLength = superDescriptors.length;
	IPropertyDescriptor[] fileDescriptors = new IPropertyDescriptor[superLength + 1];
	System.arraycopy(superDescriptors, 0, fileDescriptors, 0, superLength);
	fileDescriptors[superLength] = getInitialPropertyDescriptor();
	
	return fileDescriptors;
}
/* (non-Javadoc)
 * Method declared on IPropertySource.
 */
public Object getPropertyValue(Object key) {

	Object returnValue = super.getPropertyValue(key);
	
	if(returnValue != null)
		return returnValue;
		
	if (key.equals(IResourcePropertyConstants.P_SIZE_RES)) 
		return getSizeString((IFile) element);
	
	return null;
}
/**
 * Return a String that indicates the size of the supplied file.
 */
private String getSizeString(IFile file) {
	if (!file.isLocal(IResource.DEPTH_ZERO))
		return NOT_LOCAL_TEXT;
	else {
		IPath location = file.getLocation();
		if (location == null) {
			if (file.isLinked())
				return UNDEFINED_PATH_VARIABLE;
				
			return FILE_NOT_FOUND;
		}
		else {
			File localFile = location.toFile();
		
			if (localFile.exists()) {
				return Long.toString(localFile.length());
			}
			return FILE_NOT_FOUND;
		}
	}	
}

}