ExternalToolsPreferencePage.java

/*
 * Copyright 2008-2012 Amazon Technologies, Inc. 
 *
 * Licensed under the Apache License, Version 2.0 (the "License"); 
 * you may not use this file except in compliance with the License. 
 * You may obtain a copy of the License at:
 * 
 *    http://aws.amazon.com/apache2.0
 *
 * This file is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES 
 * OR CONDITIONS OF ANY KIND, either express or implied. See the 
 * License for the specific language governing permissions and 
 * limitations under the License. 
 */

package com.amazonaws.eclipse.ec2.preferences;

import org.eclipse.jface.preference.FileFieldEditor;
import org.eclipse.jface.preference.PreferencePage;
import org.eclipse.jface.preference.StringFieldEditor;
import org.eclipse.swt.SWT;
import org.eclipse.swt.layout.GridData;
import org.eclipse.swt.layout.GridLayout;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Control;
import org.eclipse.swt.widgets.Group;
import org.eclipse.swt.widgets.Link;
import org.eclipse.ui.IWorkbench;
import org.eclipse.ui.IWorkbenchPreferencePage;

import com.amazonaws.eclipse.core.ui.WebLinkListener;
import com.amazonaws.eclipse.ec2.Ec2Plugin;
import com.amazonaws.eclipse.ec2.PlatformUtils;

/**
 * Preference page for configuring how external tools (ex: ssh clients) are invoked.
 */
public class ExternalToolsPreferencePage
	extends PreferencePage
	implements IWorkbenchPreferencePage {

	private FileFieldEditor terminalExecutable;
	private FileFieldEditor sshClient;
	private StringFieldEditor sshOptions;
	private FileFieldEditor puttyExecutable;
	private StringFieldEditor sshUser;
	
	private static final int MAX_FIELD_EDITOR_COLUMNS = 3;	
	
	public ExternalToolsPreferencePage() {
		super("External Tool Configuration");
		setPreferenceStore(Ec2Plugin.getDefault().getPreferenceStore());
		setDescription("External Tool Configuration");
	}

	public void init(IWorkbench workbench) {}

	/* (non-Javadoc)
	 * @see org.eclipse.jface.preference.PreferencePage#createContents(org.eclipse.swt.widgets.Composite)
	 */
	@Override
	protected Control createContents(Composite parent) {
		Composite top = new Composite(parent, SWT.LEFT);
		
		// Sets the layout data for the top composite's 
		// place in its parent's layout.
		top.setLayoutData(new GridData(GridData.FILL_HORIZONTAL));
		top.setLayout(new GridLayout());
		
		Group sshClientGroup = new Group(top, SWT.LEFT);
		sshClientGroup.setLayoutData(new GridData(GridData.FILL_HORIZONTAL));
		sshClientGroup.setText("SSH Client:");
		
		PlatformUtils platformUtils = new PlatformUtils();
		if (platformUtils.isWindows()) {
			String puttyUrl = "http://www.chiark.greenend.org.uk/~sgtatham/putty/download.html";
			
			WebLinkListener webLinkListener = new WebLinkListener();
			Link l = new Link(sshClientGroup, SWT.NONE);
			l.setText("PuTTY is required for remote shell connections "
					+ "to EC2 instances from Windows.  \nYou can download it for free "
					+ "from <a href=\"" + puttyUrl + "\">" + puttyUrl + "</a>.");
			l.addListener(SWT.Selection, webLinkListener);
			GridData data = new GridData(GridData.FILL_HORIZONTAL);
			data.horizontalSpan = MAX_FIELD_EDITOR_COLUMNS;
			l.setLayoutData(data);
			
			puttyExecutable = newFileFieldEditor(PreferenceConstants.P_PUTTY_EXECUTABLE, "PuTTY Executable:", sshClientGroup);
		} else {
			// For the Mac, we use a custom AppleScript script that we ship with the
			// plugin so we don't need a seperate terminal exectuable.
			if (!platformUtils.isMac()) {
				terminalExecutable = newFileFieldEditor(PreferenceConstants.P_TERMINAL_EXECUTABLE, "Terminal:", sshClientGroup);
			}
			
			sshClient = newFileFieldEditor(PreferenceConstants.P_SSH_CLIENT, "SSH Client:", sshClientGroup);

			sshOptions = new StringFieldEditor(PreferenceConstants.P_SSH_OPTIONS, "SSH Options: ", sshClientGroup);
			sshOptions.setPage(this);
			sshOptions.setPreferenceStore(this.getPreferenceStore());
			sshOptions.load();
			sshOptions.fillIntoGrid(sshClientGroup, MAX_FIELD_EDITOR_COLUMNS);
		}
		
		sshUser = new StringFieldEditor(PreferenceConstants.P_SSH_USER, "SSH User: ", sshClientGroup);
		sshUser.setPage(this);
		sshUser.setPreferenceStore(this.getPreferenceStore());
		sshUser.load();
		sshUser.fillIntoGrid(sshClientGroup, MAX_FIELD_EDITOR_COLUMNS);
		
		// Reset the layout to three columns after the FieldEditors have mucked with it
		GridLayout layout = (GridLayout)(sshClientGroup.getLayout());
		layout.numColumns = MAX_FIELD_EDITOR_COLUMNS;
		layout.marginWidth = 10;
		layout.marginHeight = 8;
		
		return top;
	}

	/* (non-Javadoc)
	 * @see org.eclipse.jface.preference.PreferencePage#performDefaults()
	 */
	@Override
	protected void performDefaults() {
		if (terminalExecutable != null) terminalExecutable.loadDefault();
		if (sshClient != null) sshClient.loadDefault();
		if (sshOptions != null) sshOptions.loadDefault();
		if (sshUser != null) sshUser.loadDefault();
		
		if (puttyExecutable != null) puttyExecutable.loadDefault();
		
		super.performDefaults();
	}

	/* (non-Javadoc)
	 * @see org.eclipse.jface.preference.PreferencePage#performOk()
	 */
	@Override
	public boolean performOk() {
		if (terminalExecutable != null) terminalExecutable.store();
		if (sshClient != null) sshClient.store();
		if (sshOptions != null) sshOptions.store();
		if (sshUser != null) sshUser.store(); 

		if (puttyExecutable != null) puttyExecutable.store();
		
		return super.performOk();
	}

	/*
	 * Private Interface
	 */

	/**
	 * Convenience method for creating a FileFieldEditor.
	 * 
	 * @param preferenceName
	 *            The preference managed by this FileFieldEditor.
	 * @param label
	 *            The label for this FieldEditor.
	 * @param parent
	 *            The parent for this new FieldEditor widget.
	 * 
	 * @return The new FileFieldEditor.
	 */
	private FileFieldEditor newFileFieldEditor(String preferenceName, String label, Composite parent) {
		FileFieldEditor editor = new FileFieldEditor(preferenceName, label, parent);
		editor.setPage(this);
		editor.setPreferenceStore(this.getPreferenceStore());
		editor.load();
		editor.fillIntoGrid(parent, MAX_FIELD_EDITOR_COLUMNS);

		return editor;
	}
}