/*******************************************************************************
 * 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.jdt.internal.ui.wizards.buildpaths;

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

import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Control;
import org.eclipse.swt.widgets.Shell;

import org.eclipse.core.runtime.IPath;

import org.eclipse.jdt.core.IClasspathAttribute;
import org.eclipse.jdt.core.IClasspathEntry;
import org.eclipse.jdt.core.IJavaProject;

import org.eclipse.jdt.internal.corext.util.JavaModelUtil;

import org.eclipse.jdt.ui.wizards.ClasspathAttributeConfiguration;

import org.eclipse.jdt.internal.ui.JavaPlugin;

public abstract class BuildPathBasePage {

	private final ClasspathAttributeConfigurationDescriptors fAttributeDescriptors;

	public BuildPathBasePage() {
		fAttributeDescriptors= JavaPlugin.getDefault().getClasspathAttributeConfigurationDescriptors();
	}

	protected boolean editCustomAttribute(Shell shell, CPListElementAttribute elem) {
		ClasspathAttributeConfiguration config= fAttributeDescriptors.get(elem.getKey());
		if (config != null) {
			IClasspathAttribute result= config.performEdit(shell, elem.getClasspathAttributeAccess());
			if (result != null) {
				elem.setValue(result.getValue());
				return true;
			}
		}
		return false;
	}

	protected boolean removeCustomAttribute(CPListElementAttribute elem) {
		ClasspathAttributeConfiguration config= fAttributeDescriptors.get(elem.getKey());
		if (config != null) {
			IClasspathAttribute result= config.performRemove(elem.getClasspathAttributeAccess());
			if (result != null) {
				elem.setValue(result.getValue());
				return true;
			}
		}
		return false;
	}

	protected boolean canEditCustomAttribute(CPListElementAttribute elem) {
		ClasspathAttributeConfiguration config= fAttributeDescriptors.get(elem.getKey());
		if (config != null) {
			return config.canEdit(elem.getClasspathAttributeAccess());
		}
		return false;
	}

	protected boolean canRemoveCustomAttribute(CPListElementAttribute elem) {
		ClasspathAttributeConfiguration config= fAttributeDescriptors.get(elem.getKey());
		if (config != null) {
			return config.canRemove(elem.getClasspathAttributeAccess());
		}
		return false;
	}


	public abstract List getSelection();
	public abstract void setSelection(List selection, boolean expand);


	/**
	 * Adds an element to the page
	 *
	 * @param element the element to add
	 */
	public void addElement(CPListElement element) {
		// default implementation does nothing
	}

	public abstract boolean isEntryKind(int kind);

	protected void filterAndSetSelection(List list) {
		ArrayList res= new ArrayList(list.size());
		for (int i= list.size()-1; i >= 0; i--) {
			Object curr= list.get(i);
			if (curr instanceof CPListElement) {
				CPListElement elem= (CPListElement) curr;
				if (elem.getParentContainer() == null && isEntryKind(elem.getEntryKind())) {
					res.add(curr);
				}
			}
		}
		setSelection(res, false);
	}

	public static void fixNestingConflicts(CPListElement[] newEntries, CPListElement[] existing, Set modifiedSourceEntries) {
		for (int i= 0; i < newEntries.length; i++) {
			addExclusionPatterns(newEntries[i], existing, modifiedSourceEntries);
		}
	}

	private static void addExclusionPatterns(CPListElement newEntry, CPListElement[] existing, Set modifiedEntries) {
		IPath entryPath= newEntry.getPath();
		for (int i= 0; i < existing.length; i++) {
			CPListElement curr= existing[i];
			if (curr.getEntryKind() == IClasspathEntry.CPE_SOURCE) {
				IPath currPath= curr.getPath();
				if (!currPath.equals(entryPath)) {
					if (currPath.isPrefixOf(entryPath)) {
						if (addToExclusions(entryPath, curr)) {
							modifiedEntries.add(curr);
						}
					} else if (entryPath.isPrefixOf(currPath) && newEntry.getEntryKind() == IClasspathEntry.CPE_SOURCE) {
						if (addToExclusions(currPath, newEntry)) {
							modifiedEntries.add(curr);
						}
					}
				}
			}
		}
	}

	private static boolean addToExclusions(IPath entryPath, CPListElement curr) {
		IPath[] exclusionFilters= (IPath[]) curr.getAttribute(CPListElement.EXCLUSION);
		if (!JavaModelUtil.isExcludedPath(entryPath, exclusionFilters)) {
			IPath pathToExclude= entryPath.removeFirstSegments(curr.getPath().segmentCount()).addTrailingSeparator();
			IPath[] newExclusionFilters= new IPath[exclusionFilters.length + 1];
			System.arraycopy(exclusionFilters, 0, newExclusionFilters, 0, exclusionFilters.length);
			newExclusionFilters[exclusionFilters.length]= pathToExclude;
			curr.setAttribute(CPListElement.EXCLUSION, newExclusionFilters);
			return true;
		}
		return false;
	}

	protected boolean containsOnlyTopLevelEntries(List selElements) {
		if (selElements.size() == 0) {
			return true;
		}
		for (int i= 0; i < selElements.size(); i++) {
			Object elem= selElements.get(i);
			if (elem instanceof CPListElement) {
				if (((CPListElement) elem).getParentContainer() != null) {
					return false;
				}
			} else {
				return false;
			}
		}
		return true;
	}

	public abstract void init(IJavaProject javaProject);

	public abstract Control getControl(Composite parent);

	public abstract void setFocus();

}
