/*******************************************************************************
 * Copyright (c) 2000, 2003 IBM Corporation and others.
 * All rights reserved. This program and the accompanying materials 
 * are made available under the terms of the Common Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/cpl-v10.html
 * 
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/

package org.eclipse.ui.internal.ide.dialogs;

import java.io.File;

import org.eclipse.core.runtime.IPath;
import org.eclipse.core.runtime.Path;
import org.eclipse.jface.dialogs.IDialogConstants;
import org.eclipse.swt.SWT;
import org.eclipse.swt.widgets.*;
import org.eclipse.ui.dialogs.SelectionDialog;
import org.eclipse.ui.help.WorkbenchHelp;
import org.eclipse.ui.internal.ide.IHelpContextIds;
import org.eclipse.ui.internal.ide.IDEWorkbenchMessages;

/**
 * A selection dialog which shows the path variables defined in the 
 * workspace.
 * The <code>getResult</code> method returns the name(s) of the 
 * selected path variable(s).
 * <p>
 * This class may be instantiated; it is not intended to be subclassed.
 * </p>
 * <p>
 * Example:
 * <pre>
 *  PathVariableSelectionDialog dialog =
 *    new PathVariableSelectionDialog(getShell(), IResource.FOLDER);
 *	dialog.open();
 *	String[] result = (String[]) dialog.getResult();
 * </pre> 	
 * </p>
 * 
 * @since 2.1
 */
public class PathVariableSelectionDialog extends SelectionDialog {
	private static final int EXTEND_ID = IDialogConstants.CLIENT_ID + 1;
	private PathVariablesGroup pathVariablesGroup;
	private int variableType;

/**
 * Creates a path variable selection dialog.
 *
 * @param parentShell the parent shell
 * @param variableType the type of variables that are displayed in 
 * 	this dialog. <code>IResource.FILE</code> and/or <code>IResource.FOLDER</code>
 * 	logically ORed together.
 */
public PathVariableSelectionDialog(Shell parentShell, int variableType) {
	super(parentShell);
	setTitle(IDEWorkbenchMessages.getString("PathVariableSelectionDialog.title")); //$NON-NLS-1$
	this.variableType = variableType;
	pathVariablesGroup = new PathVariablesGroup(
		false, 
		variableType,
		new Listener() {
			public void handleEvent(Event event) {
				updateExtendButtonState();
			}
		}
	);
	setShellStyle(getShellStyle() | SWT.RESIZE);
}
/**
 * Handles an "Extend" button press.
 * 
 * @see org.eclipse.jface.dialogs.Dialog#buttonPressed(int)
 */
protected void buttonPressed(int buttonId) {
	if (buttonId == EXTEND_ID) {
		FileFolderSelectionDialog dialog = new FileFolderSelectionDialog(getShell(), false, variableType);
		PathVariablesGroup.PathVariableElement selection = pathVariablesGroup.getSelection()[0];
		dialog.setTitle(IDEWorkbenchMessages.getString("PathVariableSelectionDialog.ExtensionDialog.title")); //$NON-NLS-1$
		dialog.setMessage(IDEWorkbenchMessages.format("PathVariableSelectionDialog.ExtensionDialog.description", new Object[] {selection.name})); //$NON-NLS-1$
		dialog.setInput(selection.path.toFile());
		if (dialog.open() == FileFolderSelectionDialog.OK && pathVariablesGroup.performOk()) {
			setExtensionResult(selection, (File) dialog.getResult()[0]);
			super.okPressed();
		}
	}
	else
		super.buttonPressed(buttonId);
}
/* (non-Javadoc)
 * Method declared in Window.
 */
protected void configureShell(Shell shell) {
	super.configureShell(shell);
	WorkbenchHelp.setHelp(shell, IHelpContextIds.PATH_VARIABLE_SELECTION_DIALOG);
}
/**
 * Adds an Extend button in addition to OK, Cancel.
 * 
 * @see org.eclipse.jface.dialogs.Dialog#createButtonsForButtonBar(Composite)
 */
protected void createButtonsForButtonBar(Composite parent) {
	createButton(parent, IDialogConstants.OK_ID, IDialogConstants.OK_LABEL, true);
	createButton(parent, EXTEND_ID, IDEWorkbenchMessages.getString("PathVariableSelectionDialog.extendButton"), false);//$NON-NLS-1$	
	createButton(parent, IDialogConstants.CANCEL_ID, IDialogConstants.CANCEL_LABEL, false);
	updateExtendButtonState();
}
/* (non-Javadoc)
 * Method declared on Dialog.
 */
protected Control createDialogArea(Composite parent) {
	// create composite 
	Composite dialogArea = (Composite)super.createDialogArea(parent);

	pathVariablesGroup.createContents(dialogArea);
	return dialogArea;
}
/**
 * Disposes the path variables group.
 * @see org.eclipse.jface.window.Window#close()
 */
public boolean close() {
	pathVariablesGroup.dispose();
	return super.close();
}
/**
 * Sets the dialog result to the selected path variable name(s). 
 */
protected void okPressed() {
	if (pathVariablesGroup.performOk()) {
		PathVariablesGroup.PathVariableElement[] selection = pathVariablesGroup.getSelection();
		String[] variableNames = new String[selection.length];
		
		for (int i = 0; i < selection.length; i++)
			variableNames[i] = selection[i].name;
		setSelectionResult(variableNames);
	}
	else {
		setSelectionResult(null);
	}
	super.okPressed();
}
/**
 * Sets the dialog result to the concatenated variable name and extension.
 * 
 * @param variable variable selected in the variables list and extended
 * 	by <code>extensionFile</code>
 * @param extensionFile file selected to extend the variable.
 */
private void setExtensionResult(PathVariablesGroup.PathVariableElement variable, File extensionFile) {
	IPath extensionPath = new Path(extensionFile.getPath());
	int matchCount = extensionPath.matchingFirstSegments(variable.path);
	IPath resultPath = new Path(variable.name);
		
	extensionPath = extensionPath.removeFirstSegments(matchCount);
	resultPath = resultPath.append(extensionPath);			
	setSelectionResult(new String[] {resultPath.toOSString()});
}
/**
 * Updates the enabled state of the Extend button based on the 
 * current variable selection.
 */
protected void updateExtendButtonState() {
	PathVariablesGroup.PathVariableElement[] selection = pathVariablesGroup.getSelection();
	Button extendButton = getButton(EXTEND_ID);
	
	if (extendButton == null)
		return;
	if (selection.length == 1) {
		File file = selection[0].path.toFile();	
		if (file.exists() == false || file.isFile())
			extendButton.setEnabled(false);
		else
			extendButton.setEnabled(true);
	}
	else
		extendButton.setEnabled(false);	
}

}