/*******************************************************************************
 * Copyright (c) 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.equinox.internal.provisional.p2.ui.dialogs;

import org.eclipse.equinox.internal.provisional.p2.metadata.IInstallableUnit;
import org.eclipse.equinox.internal.provisional.p2.ui.model.CategoryElement;
import org.eclipse.equinox.internal.provisional.p2.ui.model.IUElement;
import org.eclipse.equinox.internal.provisional.p2.ui.query.IUPropertyUtils;
import org.eclipse.equinox.internal.provisional.p2.ui.viewers.IUColumnConfig;
import org.eclipse.jface.viewers.Viewer;
import org.eclipse.ui.dialogs.PatternFilter;

/**
 * A class that handles filtering IU's based on a supplied
 * matching string.
 *  
 * @since 3.2
 *
 */
public class AvailableIUPatternFilter extends PatternFilter {

	boolean checkName, checkVersion, checkId = false;
	String patternString;

	/**
	 * Create a new instance of a AvailableIUPatternFilter 
	 */
	public AvailableIUPatternFilter(IUColumnConfig[] columnConfig) {
		super();
		for (int i = 0; i < columnConfig.length; i++) {
			int field = columnConfig[i].columnField;
			if (field == IUColumnConfig.COLUMN_ID)
				checkId = true;
			else if (field == IUColumnConfig.COLUMN_NAME)
				checkName = true;
			else if (field == IUColumnConfig.COLUMN_VERSION)
				checkVersion = true;
		}

	}

	/*
	 * (non-Javadoc)
	 * @see org.eclipse.ui.internal.dialogs.PatternFilter#isElementSelectable(java.lang.Object)
	 */
	public boolean isElementSelectable(Object element) {
		return element instanceof IUElement && !(element instanceof CategoryElement);
	}

	/*
	 * Overridden to remember the pattern string for an optimization
	 * in isParentMatch
	 * (non-Javadoc)
	 * @see org.eclipse.ui.dialogs.PatternFilter#setPattern(java.lang.String)
	 */
	public void setPattern(String patternString) {
		super.setPattern(patternString);
		this.patternString = patternString;
	}

	/*
	 * Overridden to avoid getting children unless there is actually
	 * a filter.
	 * (non-Javadoc)
	 * @see org.eclipse.ui.dialogs.PatternFilter#isParentMatch(org.eclipse.jface.viewers.Viewer, java.lang.Object)
	 */
	protected boolean isParentMatch(Viewer viewer, Object element) {
		if (patternString == null || patternString.length() == 0)
			return true;
		return super.isParentMatch(viewer, element);
	}

	/* (non-Javadoc)
	 * @see org.eclipse.ui.dialogs.PatternFilter#isElementMatch(org.eclipse.jface.viewers.Viewer, java.lang.Object)
	 */
	protected boolean isLeafMatch(Viewer viewer, Object element) {
		if (element instanceof CategoryElement) {
			return false;
		}

		String text = null;
		if (element instanceof IUElement) {
			IInstallableUnit iu = ((IUElement) element).getIU();
			if (checkName) {
				// Get the iu name in the default locale
				text = IUPropertyUtils.getIUProperty(iu, IInstallableUnit.PROP_NAME);
				if (text != null && wordMatches(text))
					return true;
			}
			if (checkId) {
				text = iu.getId();
				if (wordMatches(text)) {
					return true;
				}
			}
			if (checkVersion) {
				text = iu.getVersion().toString();
				if (wordMatches(text))
					return true;
			}
		}
		return false;
	}
}