/*******************************************************************************
 * Copyright (c) 2002, 2005 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
 *     Jens Lukowski/Innoopract - initial renaming/restructuring
 *     
 *******************************************************************************/
package org.eclipse.wst.xml.ui.internal.catalog;

import org.eclipse.jface.preference.PreferencePage;
import org.eclipse.jface.viewers.ISelection;
import org.eclipse.jface.viewers.ISelectionChangedListener;
import org.eclipse.jface.viewers.IStructuredSelection;
import org.eclipse.jface.viewers.SelectionChangedEvent;
import org.eclipse.swt.SWT;
import org.eclipse.swt.events.SelectionAdapter;
import org.eclipse.swt.events.SelectionEvent;
import org.eclipse.swt.events.SelectionListener;
import org.eclipse.swt.layout.GridData;
import org.eclipse.swt.layout.GridLayout;
import org.eclipse.swt.widgets.Button;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Control;
import org.eclipse.swt.widgets.Group;
import org.eclipse.swt.widgets.Label;
import org.eclipse.ui.IWorkbench;
import org.eclipse.ui.IWorkbenchPreferencePage;
import org.eclipse.wst.xml.core.internal.XMLCorePlugin;
import org.eclipse.wst.xml.core.internal.catalog.CatalogSet;
import org.eclipse.wst.xml.core.internal.catalog.provisional.ICatalog;
import org.eclipse.wst.xml.core.internal.catalog.provisional.ICatalogEntry;
import org.eclipse.wst.xml.core.internal.catalog.provisional.ICatalogEvent;
import org.eclipse.wst.xml.core.internal.catalog.provisional.ICatalogListener;
import org.eclipse.wst.xml.core.internal.catalog.provisional.INextCatalog;

public class XMLCatalogPreferencePage extends PreferencePage implements IWorkbenchPreferencePage, ICatalogListener {

	protected XMLCatalogEntriesView catalogEntriesView;

	protected ICatalog workingUserCatalog;

	protected ICatalog systemCatalog;

	protected ICatalog userCatalog;

	protected ICatalog defaultCatalog;

	protected Button advancedButton;

	public XMLCatalogPreferencePage() {
		defaultCatalog = XMLCorePlugin.getDefault().getDefaultXMLCatalog();
		INextCatalog[] nextCatalogs = defaultCatalog.getNextCatalogs();
		for (int i = 0; i < nextCatalogs.length; i++) {
			INextCatalog catalog = nextCatalogs[i];
			ICatalog referencedCatalog = catalog.getReferencedCatalog();
			if (referencedCatalog != null) {
				if (XMLCorePlugin.SYSTEM_CATALOG_ID.equals(referencedCatalog.getId())) {
					systemCatalog = referencedCatalog;
				}
				else if (XMLCorePlugin.USER_CATALOG_ID.equals(referencedCatalog.getId())) {
					userCatalog = referencedCatalog;
				}
			}
		}
	}

	public void dispose() {
		super.dispose();
		workingUserCatalog.removeListener(this);
	}

	/**
	 * Refresh the view in responce to an event sent by the Catalog
	 */
	public void catalogChanged(ICatalogEvent event) {
		catalogEntriesView.updatePage();
	}

	/**
	 * Creates preference page controls on demand.
	 * 
	 * @param parent
	 *            the parent for the preference page
	 */
	protected Control createContents(Composite parent) {
		// we create a working copy of the 'User Settings' for the Catalog
		// that we can modify
		CatalogSet tempCatalogSet = new CatalogSet();
		workingUserCatalog = tempCatalogSet.lookupOrCreateCatalog("working", ""); //$NON-NLS-1$ //$NON-NLS-2$

		// TODO: add entries from the nested catalogs as well
		workingUserCatalog.addEntriesFromCatalog(userCatalog);
		workingUserCatalog.addListener(this);
		noDefaultAndApplyButton();
		Composite composite = new Composite(parent, SWT.NULL);
		// WorkbenchHelp.setHelp(composite, new
		// ControlContextComputer(composite,
		// XMLBuilderContextIds.XMLP_CATALOG_PAGE));
		composite.setLayout(new GridLayout());
		composite.setLayoutData(new GridData(GridData.FILL_BOTH));
		createCatalogEntriesView(composite);
		createCatalogDetailsView(composite);
		createAdvancedButton(composite);
		// catalogEntriesView.updatePage();
		applyDialogFont(composite);

		return composite;
	}

	protected void createAdvancedButton(Composite composite) {
		Composite panel = new Composite(composite, SWT.NONE);
		GridLayout gridLayout = new GridLayout();
		gridLayout.numColumns = 3;
		panel.setLayout(gridLayout);
		panel.setLayoutData(new GridData(GridData.FILL_HORIZONTAL));
		// TODO... is there a better way to expand the page width?
		// This invisible label is created to force the width of the page to
		// be
		// wide enough to show
		// the rather long uri and key fields of a catalog entry.
		Label widthFudger = new Label(panel, SWT.NONE);
		String widthFudgerString = ""; //$NON-NLS-1$
		for (int i = 0; i < 55; i++) {
			widthFudgerString += "x"; //$NON-NLS-1$
		}
		widthFudger.setText(widthFudgerString);
		widthFudger.setVisible(false);
		Composite placeHolder = new Composite(panel, SWT.NONE);
		placeHolder.setLayoutData(new GridData(GridData.FILL_HORIZONTAL));
		advancedButton = new Button(panel, SWT.NONE);
		advancedButton.setText(XMLCatalogMessages.UI_LABEL_ADVANCED);
		SelectionListener selectionListener = new SelectionAdapter() {
			public void widgetSelected(SelectionEvent e) {
				AdvancedOptionsDialog dialog = new AdvancedOptionsDialog(getShell(), workingUserCatalog);
				dialog.create();
				dialog.getShell().setText(XMLCatalogMessages.UI_LABEL_ADVANCED_XML_CATALOG_PREFS);
				dialog.setBlockOnOpen(true);
				dialog.open();
			}
		};
		advancedButton.addSelectionListener(selectionListener);
	}

	public boolean isSameFileName(String a, String b) {
		boolean result = false;
		if ((a == null) && (b == null)) {
			result = true;
		}
		else if ((a != null) && (b != null)) {
			result = a.equals(b);
		}
		return result;
	}

	protected void createCatalogEntriesView(Composite parent) {
		Group group = new Group(parent, SWT.NONE);
		group.setLayout(new GridLayout());
		group.setLayoutData(new GridData(GridData.FILL_BOTH));
		group.setText(XMLCatalogMessages.UI_LABEL_USER_ENTRIES);
		group.setToolTipText(XMLCatalogMessages.UI_LABEL_USER_ENTRIES_TOOL_TIP);
		// WorkbenchHelp.setHelp(userEntriesGroup, new
		// ControlContextComputer(userEntriesGroup,
		// XMLBuilderContextIds.XMLP_CATALOG_USER_GROUP));
		catalogEntriesView = new XMLCatalogEntriesView(group, workingUserCatalog, systemCatalog);
		catalogEntriesView.setLayoutData(new GridData(GridData.FILL_BOTH));
	}

	protected void createCatalogDetailsView(Composite parent) {
		Group detailsGroup = new Group(parent, SWT.NONE);
		detailsGroup.setLayoutData(new GridData(GridData.FILL_HORIZONTAL));
		detailsGroup.setLayout(new GridLayout());
		detailsGroup.setText(XMLCatalogMessages.UI_LABEL_DETAILS);
		final XMLCatalogEntryDetailsView detailsView = new XMLCatalogEntryDetailsView(detailsGroup);
		ISelectionChangedListener listener = new ISelectionChangedListener() {
			public void selectionChanged(SelectionChangedEvent event) {
				ISelection selection = event.getSelection();
				Object selectedObject = (selection instanceof IStructuredSelection) ? ((IStructuredSelection) selection).getFirstElement() : null;
				if (selectedObject instanceof ICatalogEntry) {
					ICatalogEntry entry = (ICatalogEntry) selectedObject;
					detailsView.setCatalogElement(entry);
				}
				else if (selectedObject instanceof INextCatalog) {
					INextCatalog entry = (INextCatalog) selectedObject;
					detailsView.setCatalogElement(entry);
				}
				else {
					detailsView.setCatalogElement((ICatalogEntry) null);
				}

			}
		};
		catalogEntriesView.getViewer().addSelectionChangedListener(listener);
	}

	/**
	 * Do anything necessary because the OK button has been pressed.
	 * 
	 * @return whether it is okay to close the preference page
	 */
	public boolean performOk() {
		return storeValues();
	}

	/**
	 * @see IWorkbenchPreferencePage
	 */
	public void init(IWorkbench workbench) {
	}

	/**
	 * Stores the values of the controls back to the preference store.
	 */
	private boolean storeValues() {
		// dw Object fileObject = null;
		try {
			// update the userCatalog so that its the same as the working
			// catalog
			userCatalog.clear();
			// TODO add entries from the nested catalogs?
			userCatalog.addEntriesFromCatalog(workingUserCatalog);
			// now save the userCatalog
			userCatalog.save();
		}
		catch (Exception e) {
		}
		return true;
	}


}