// NewIdentifiablePage.java
package org.eclipse.stem.ui.wizards;

/*******************************************************************************
 * Copyright (c) 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
 *******************************************************************************/

import java.util.List;

import org.eclipse.core.resources.IProject;
import org.eclipse.core.resources.IResource;
import org.eclipse.core.resources.ResourcesPlugin;
import org.eclipse.core.runtime.IPath;
import org.eclipse.core.runtime.Path;
import org.eclipse.emf.common.util.URI;
import org.eclipse.jface.viewers.ISelection;
import org.eclipse.jface.viewers.IStructuredSelection;
import org.eclipse.jface.wizard.WizardPage;
import org.eclipse.stem.core.common.Identifiable;
import org.eclipse.stem.core.common.presentation.CoreEditorAdvisor;
import org.eclipse.stem.ui.Activator;
import org.eclipse.stem.ui.Utility;
import org.eclipse.stem.ui.views.explorer.IdentifiableTreeNode;
import org.eclipse.swt.SWT;
import org.eclipse.swt.events.ModifyEvent;
import org.eclipse.swt.events.ModifyListener;
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.Combo;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Label;
import org.eclipse.swt.widgets.Text;

/**
 * This class is the {@link WizardPage} that is the super class of all wizard
 * pages used to specify the details of an {@link Identifiable}.
 * 
 * @see DublinCorePage
 * @see NewIdentifiableWizard
 */
abstract public class NewIdentifiablePage extends WizardPage {

	/**
	 * This {@link Combo} will be populated with the names of the projects in
	 * the workspace that the {@link Identifiable} can be created in.
	 */
	protected Combo projectNamesCombo;

	/**
	 * The name of the file in which the {@link Identifiable} will be
	 * serialized.
	 * 
	 * @see NewIdentifiableWizard#createIdentifiable(org.eclipse.core.runtime.IProgressMonitor,
	 *      org.eclipse.emf.common.util.URI)
	 */
	protected Text serializationFileNameField;

	/**
	 * This {@link Composite} is created by the subclasses with the call to
	 * {@link #createSpecificComposite(Composite)}. This {@link Composite}
	 * contains all of the interface features for defining the details of the
	 * {@link Identifiable} to be created.
	 */
	private Composite specificComposite;

	/**
	 * The collection of STEM projects in the current workspace. This will be
	 * used to populate {@link #projectNamesCombo}.
	 */
	protected List<IProject> stemProjects = null;

	/**
	 * Remember the last project used if the current selection is not referencing 
	 * an existing project
	 */
	
	static IProject lastProject = null;
	
	/**
	 * This {@link ModifyListener} is attached to those widgets whose contents
	 * need to be verified for correctness. Whenever one of those is modified, a
	 * call to {@link #validatePage()} is made which then returns
	 * <code>true</code> or <code>false</code>. This value is passed to
	 * {@link #setPageComplete(boolean)} which then enables or disables the
	 * buttons at the bottom of the page. The attachment is done in the method
	 * {@link #createProjectComposite(Composite)} and in
	 * {@link #createSerializationComposite(Composite)}
	 */
	protected ModifyListener projectValidator = new ModifyListener() {
		public void modifyText(@SuppressWarnings("unused") final ModifyEvent e) {
			setPageComplete(validatePage());
		}
	};

	/**
	 * @param pageName
	 *            the name of the page, this is passed up by a subclass.
	 */
	protected NewIdentifiablePage(final String pageName) {
		super(pageName);
	} // NewIdentifiablePage

	/**
	 * @see org.eclipse.jface.dialogs.IDialogPage#createControl(org.eclipse.swt.widgets.Composite)
	 */
	public void createControl(final Composite parent) {
		/*
		 * Creates a {@link Composite} and calls {@link  #setControl(org.eclipse.swt.widgets.Control)}. Basically, it adds
		 * three things to the Composite it creates, a "project composite" an
		 * "identifiable composite" and a "specific composite". The first is
		 * common to all pages and is used to specify which project the
		 * Identifiable will be serialized in. The second, also common to all
		 * pages, is used to specify the name of the serialization file for the
		 * Identifiable. The third is for the specific details for defining the
		 * Identifiable.
		 */
		// Page Composite
		final Composite pageComposite = new Composite(parent, SWT.NONE);
		final GridLayout pageLayout = new GridLayout();
		pageLayout.numColumns = 1;
		pageLayout.verticalSpacing = 12;
		pageComposite.setLayout(pageLayout);

		final GridData pageLayoutData = new GridData();
		pageLayoutData.verticalAlignment = GridData.FILL;
		pageLayoutData.grabExcessVerticalSpace = true;
		pageLayoutData.horizontalAlignment = GridData.FILL;
		pageComposite.setLayout(pageLayout);

		createProjectComposite(pageComposite);

		// Horizontal Separator
		final Label seperator = new Label(pageComposite, SWT.HORIZONTAL
				| SWT.SEPARATOR);
		seperator.setLayoutData(new GridData(GridData.FILL_HORIZONTAL));

		final Composite identifiableComposite = createSerializationComposite(pageComposite);
		identifiableComposite.setLayoutData(new GridData(
				GridData.FILL_HORIZONTAL));

		// Add anything that is specific to the type of wizard
		specificComposite = createSpecificComposite(pageComposite);
		// Was there anything?
		if (specificComposite != null) {
			// Yes
			final GridData gd = new GridData(GridData.FILL_HORIZONTAL);
			gd.grabExcessHorizontalSpace = true;
			specificComposite.setLayoutData(gd);
		} // if

		setPageComplete(validatePage());
		parent.pack();
		setControl(pageComposite);
	} // createControl

	/**
	 * @param parent
	 *            the parent {@link Composite}
	 */
	private void createProjectComposite(final Composite parent) {
		final Composite projectComposite = new Composite(parent, SWT.None);
		final GridLayout projectCompositeLayout = new GridLayout();
		projectCompositeLayout.numColumns = 3;
		projectCompositeLayout.verticalSpacing = 12;
		projectCompositeLayout.marginHeight = 0;
		projectCompositeLayout.marginWidth = 0;
		projectComposite.setLayout(projectCompositeLayout);

		final GridData projectCompositeLayoutData = new GridData();
		projectCompositeLayoutData.horizontalAlignment = GridData.FILL;
		projectComposite.setLayoutData(projectCompositeLayoutData);

		// Project Label
		final Label projectLabel = new Label(projectComposite, SWT.LEFT);
		projectLabel.setText(Messages.getString("NIdWiz.project") + ":"); //$NON-NLS-1$ //$NON-NLS-2$
		final GridData projectLabelLayoutData = new GridData();
		projectLabelLayoutData.horizontalSpan = 1;
		projectLabelLayoutData.horizontalAlignment = GridData.FILL;
		projectLabel.setLayoutData(projectLabelLayoutData);

		// Project Combo
		projectNamesCombo = new Combo(projectComposite, SWT.BORDER
				| SWT.READ_ONLY);
		final GridData projectFieldLayoutData = new GridData();
		projectFieldLayoutData.horizontalAlignment = GridData.FILL;
		projectFieldLayoutData.grabExcessHorizontalSpace = true;
		projectFieldLayoutData.horizontalSpan = 1;
		projectNamesCombo.setLayoutData(projectFieldLayoutData);

		// initialize the project field to point to the selected project
		initializeProjectCombo(projectNamesCombo);

		// The projectValidator will look at the contents of the field and
		// determine if it refers to a valid project.
		projectNamesCombo.addModifyListener(projectValidator);
		
		// Remember the selection done for future 
		projectNamesCombo.addSelectionListener(new SelectionListener() {
			
			public void widgetSelected(SelectionEvent e) {
				NewIdentifiablePage.lastProject = NewIdentifiablePage.this.getSelectedProject();
			}
			
			public void widgetDefaultSelected(SelectionEvent e) {
				
			}
		});
		// Project Browse Button
		final Button projectFieldBrowseButton = new Button(projectComposite,
				SWT.PUSH);
		projectFieldBrowseButton.setText(Messages.getString("NIdWiz.browse")); //$NON-NLS-1$

		projectFieldBrowseButton.addSelectionListener(new SelectionAdapter() {

			/**
			 * The browse button will pop-up a file search dialog and allow the
			 * user to specify the project
			 * 
			 * @see org.eclipse.swt.events.SelectionAdapter#widgetSelected(org.eclipse.swt.events.SelectionEvent)
			 */
			@Override
			public void widgetSelected(
					@SuppressWarnings("unused") final SelectionEvent e) {
				final String filePath = CoreEditorAdvisor.openFilePathDialog(
						getShell(), "*", SWT.OPEN); //$NON-NLS-1$
				if (filePath != null) {
					projectNamesCombo.setText(filePath);
				}
			}
		});
	} // createProjectComposite

	/**
	 * @param parent
	 *            the parent {@link Composite}
	 * @return a {@link Composite} in which the user can specify the name of the
	 *         file in which the {@link Identifiable} should be serialized.
	 */
	private Composite createSerializationComposite(final Composite parent) {
		final Composite retValue = new Composite(parent, SWT.NONE);
		GridData gridData;

		final GridLayout identifableCompositeLayout = new GridLayout();
		identifableCompositeLayout.numColumns = 3;
		identifableCompositeLayout.verticalSpacing = 12;
		identifableCompositeLayout.marginHeight = 0;
		identifableCompositeLayout.marginWidth = 0;
		retValue.setLayout(identifableCompositeLayout);
		gridData = new GridData();
		// identifiableCompositeLayoutData.horizontalSpan=1;
		gridData.horizontalAlignment = GridData.FILL;
		// identifiableCompositeLayoutData.grabExcessHorizontalSpace = true;
		retValue.setLayoutData(gridData);

		// Serialization file name label
		final Label serializationFileNameLabel = new Label(retValue, SWT.NONE);
		serializationFileNameLabel
				.setText(Messages.getString("NIdWiz.name") + ":"); //$NON-NLS-1$ //$NON-NLS-2$
		gridData = new GridData();
		gridData.horizontalSpan = 1;
		gridData.horizontalAlignment = SWT.LEAD;
		serializationFileNameLabel.setLayoutData(gridData);

		serializationFileNameField = new Text(retValue, SWT.BORDER);
		gridData = new GridData();
		gridData.horizontalAlignment = GridData.FILL;
		gridData.grabExcessHorizontalSpace = true;
		gridData.horizontalSpan = 1;
		serializationFileNameField.setLayoutData(gridData);

		serializationFileNameField.addModifyListener(projectValidator);

		return retValue;
	} // createSerializationComposite

	/**
	 * @param parent
	 *            the parent {@link Composite}, typically the one created in
	 *            {@link #createControl(Composite)}.
	 */
	protected Composite createSpecificComposite(final Composite parent) {
		// The NewModelWizard doesn't provide a "specific composite" so we don't
		// make this method abstract.
		return null;
	} // createSpecificComposite

	/**
	 * @return the project selected by the user.
	 */
	public IProject getSelectedProject() {
		int ind = projectNamesCombo.getSelectionIndex();
		if(ind != -1)
			return stemProjects.get(projectNamesCombo.getSelectionIndex());
		return null;
	} // getSelectedProject

	/**
	 * @param projectCombo
	 *            the {@link Combo} to be initialized with the names of the
	 *            projects.
	 */
	private void initializeProjectCombo(final Combo projectCombo) {

		IProject selectedProject = getWorkSpaceSelectedProject();

		if(selectedProject == null) selectedProject = lastProject;
		
		// Get the Projects that are STEM projects
		int index = 0;
		int i = 0;
		for (final IProject project : getSTEMProjects()) {
			// Is the STEM project selected?
			if (project.equals(selectedProject)) {
				// Yes
				index = i;
			}

			final String projectName = project.getName();
			projectCombo.add(projectName);
			i++;
		} // for each STEM project
		projectCombo.setFocus();
		projectCombo.select(index);
		NewIdentifiablePage.lastProject = this.getSelectedProject();
	} // initializeProjectField

	private IProject getWorkSpaceSelectedProject() {
		IProject retValue = null;
		// Find the name of the currently selected project, if there is one
		final ISelection selection = Activator.getDefault().getWorkbench()
				.getActiveWorkbenchWindow().getSelectionService()
				.getSelection();
		// Structured Selection that might have a project?
		if (selection instanceof IStructuredSelection) {
			for (Object obj : ((IStructuredSelection) selection).toList()) {
				// Project?
				if (obj instanceof IProject) {
					retValue = (IProject) obj;
					break;
				}
				// File or Folder? (in a Project)
				else if (obj instanceof IResource) {
					// Yes
					retValue = ((IResource) obj).getProject();
					break;
				} // else if File or Folder
				// Identifiable?
				else if (obj instanceof Identifiable) {
					URI uri = ((Identifiable) obj).getURI();
					String puri = uri.toPlatformString(true);
					if(puri != null) {
						final IPath path = new Path(puri);
						retValue = ResourcesPlugin.getWorkspace().getRoot()
								.getFile(path).getProject();
					} // if puri is null no path is available, return null
					break;
				} // else if Identifiable
				// IdentifiableTreeNode?
				else if (obj instanceof IdentifiableTreeNode) {
					retValue = ((IdentifiableTreeNode) obj).getProject();
					break;
				} // else if IdentifiableTreeNode

			} // for each selected object
		} // if structured selection

		return retValue;
	} // getWorkSpaceSelectedProject

	/**
	 * @return a List of the projects in the workspace that have STEM Project
	 *         "nature"
	 * 
	 * @see org.eclipse.stem.core.Constants#ID_STEM_PROJECT_NATURE
	 */
	private List<IProject> getSTEMProjects() {
		// Refresh
		stemProjects = Utility.getSTEMProjectsFromWorkspace();
		return stemProjects;
	} // getSTEMProjects

	/**
	 * @return <code>true</code> if the page is complete and ready to go
	 */
	protected boolean validatePage() {
		boolean retValue = true;
		setErrorMessage(null);

		// Are there any projects?
		if (getSTEMProjects().size() == 0) {
			// No
			setErrorMessage(Messages.getString("NIdWiz.noProjErr"));
			retValue = false;
		} // if no projects

		// Is the serialization file name missing?
		if (retValue && serializationFileNameField.getText() == null
				|| "".equals(serializationFileNameField.getText().trim())) {
			// Yes
			setErrorMessage(Messages.getString("NIdWiz.nameMissingErr")); //$NON-NLS-1$
			retValue = false;
		}

		// Is the serialization file name valid?
		if (retValue && !serializationFileNameIsValid()) {
			// No
			setErrorMessage(Messages.getString("NIdWiz.nameErr")); //$NON-NLS-1$
			retValue = false;
		}

		return retValue;
	} // validatePage

	/**
	 * @return <code>true</code> if the serialization file name specified for
	 *         the {@link Identifiable} to be created is a valid name.
	 */
	private boolean serializationFileNameIsValid() {
		final String name = serializationFileNameField.getText();

		if (name == null) {
			return false;
		}

		final String trimedName = name.trim();

		return !(trimedName.equals("") || trimedName.contains(" ")); //$NON-NLS-1$ //$NON-NLS-2$
	} // serializationFileNameIsValid

	/**
	 * @return the value for the {@link DublinCore#getTitle()} attribute on the
	 *         {@link DublinCorePage}.
	 */
	protected String getDCTitle() {
		return getDCDescription();
	} // getDCTitle

	/**
	 * @return the value for a {@link DublinCore#getDescription()} attribute on
	 *         the {@link DublinCorePage}.
	 */
	abstract protected String getDCDescription();

	/**
	 * @return a value suitable for {@link DublinCore#setValid(String)}
	 */
	protected String getDCValidDateRange() {
		return "";
	} // getDCValidDateRange
} // NewIdentifiablePage