/*

* Copyright (c) 2009 Nokia Corporation and/or its subsidiary(-ies).

* All rights reserved.

* This component and the accompanying materials are made available

* under the terms of the License "Eclipse Public License v1.0"

* which accompanies this distribution, and is available

* at the URL "http://www.eclipse.org/legal/epl-v10.html".

*

* Initial Contributors:

* Nokia Corporation - initial contribution.

*

* Contributors:

*

* Description: 

*

*/

package com.nokia.cpp.internal.api.utils.ui;

import org.eclipse.jface.dialogs.IDialogConstants;

import org.eclipse.jface.dialogs.MessageDialogWithToggle;

import org.eclipse.jface.preference.IPreferenceStore;

import org.eclipse.swt.widgets.Shell;

import org.eclipse.ui.plugin.AbstractUIPlugin;

import com.nokia.cpp.internal.api.utils.core.Check;

/**

 * Utility that wraps a JFace dialog to which asks the user

 * a boolean question.  The dialog has a checkbox indicating whether

 * to remember the decision (yea or nay) for later.

 * <p>

 * This differs from QueryWithBooleanPrefDialog which only

 * remembers a decision if it was answered one way or the other.

 * 

 * @see org.eclipse.jface.dialogs.MessageDialogWithToggle

 * @see com.nokia.sdt.utils.ui.QueryWithBooleanPrefDialog

 *

 */

public class QueryWithTristatePrefDialog  {

	public static final int QUERY_YES_NO = 1;

	public static final int QUERY_OK_CANCEL = 2;

	protected String prefName;

	protected boolean valueToSkipDialog;

	protected boolean dontAskValue;

	private IPreferenceStore preferences;

	private Shell parentShell;

	private String title;

	private String prompt;

	private boolean initialSetting;

	private int type;

	/**

	 * Create the dialog

	 * @param parentShell parent of the dialog, null for default

	 * @param title the dialog title, required

	 * @param prompt the prompt text, required

	 * @param plugin the plugin owning the preference, required

	 * @param prefName the name of the boolean preference, required

	 * @param initialSetting the initial setting for the toggle

	 * @param type the query to perform (QUERY_YES_NO, QUERY_OK_CANCEL)

	 */

	public QueryWithTristatePrefDialog(Shell parentShell, 

			String title, String prompt,

			AbstractUIPlugin plugin, String prefName, 

			boolean initialSetting, int type) {

		Check.checkArg(type == QUERY_OK_CANCEL || type == QUERY_YES_NO);

		this.parentShell = parentShell;

		this.title = title;

		this.prompt = prompt;

		this.preferences = plugin.getPreferenceStore();

		this.prefName = prefName;

		this.initialSetting = initialSetting;

		this.type = type;

	}

	/**

	 * Main method to query for a setting.  If the preference setting 

	 * is at the "don't skip" value then the dialog is run. If the

	 * preference setting is at the skip value then the retained value 

	 * is always returned.<p>

	 * If the user clicks OK with the "don't ask" checkbox checked

	 * then the preference setting is automatically updated.

	 * @return true if the "always" pref is set or the positive value (yes/ok) 

	 * was selected, false if the "never" pref or the negative value (no/cancel)

	 * was selected.

	 */

	public boolean doQuery() {

		String value = preferences.contains(prefName)

					? preferences.getString(prefName)

					: null;

        if (value != null) {

        	if (value.equals(MessageDialogWithToggle.ALWAYS))

        		return true;

        	if (value.equals(MessageDialogWithToggle.NEVER))

        		return false;

        	// else, bogus, and go to dialog

        }

		MessageDialogWithToggle dialog;

		boolean confirmed = false;

		if (type == QUERY_YES_NO) {

			dialog = MessageDialogWithToggle.openYesNoQuestion(

				parentShell, title, prompt, "Don't ask to manage dependencies again.",

				initialSetting, preferences, 

				prefName);

			confirmed = dialog.getReturnCode() == IDialogConstants.YES_ID;

		}

		else if (type == QUERY_OK_CANCEL) {

			dialog = MessageDialogWithToggle.openYesNoQuestion(

					parentShell, title, prompt, null,

					initialSetting, preferences, 

					prefName);

			confirmed = dialog.getReturnCode() == IDialogConstants.OK_ID;

		}

		else

			Check.checkState(false);

		return confirmed;

	}

}