package com.windowtester.examples.gef.uml.wizards;

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.ObjectOutputStream;

import org.eclipse.core.resources.IFile;
import org.eclipse.jface.viewers.IStructuredSelection;
import org.eclipse.jface.wizard.Wizard;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.ui.INewWizard;
import org.eclipse.ui.IWorkbench;
import org.eclipse.ui.IWorkbenchPage;
import org.eclipse.ui.PartInitException;
import org.eclipse.ui.dialogs.WizardNewFileCreationPage;
import org.eclipse.ui.ide.IDE;

import com.windowtester.examples.gef.uml.model.ClassDiagram;

/**
 * Create new new .cd-file. Those files can be used with the ClassDiagramEditor
 * (see plugin.xml).
 * 
 * @author Elias Volanakis
 * @author Phil Quitslund
 */
public class ClassDiagramCreationWizard extends Wizard implements INewWizard {

	private static int fileCount = 1;
	private CreationPage page1;

	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.jface.wizard.IWizard#addPages()
	 */
	public void addPages() {
		// add pages to this wizard
		addPage(page1);
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.ui.IWorkbenchWizard#init(org.eclipse.ui.IWorkbench,
	 *      org.eclipse.jface.viewers.IStructuredSelection)
	 */
	public void init(IWorkbench workbench, IStructuredSelection selection) {
		// create pages for this wizard
		page1 = new CreationPage(workbench, selection);
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.jface.wizard.IWizard#performFinish()
	 */
	public boolean performFinish() {
		return page1.finish();
	}

	/**
	 * This WizardPage can create an empty .shapes file for the ClassDiagramEditor.
	 */
	private class CreationPage extends WizardNewFileCreationPage {
		private static final String DEFAULT_EXTENSION = ".cd";
		private final IWorkbench workbench;

		/**
		 * Create a new wizard page instance.
		 * 
		 * @param workbench
		 *            the current workbench
		 * @param selection
		 *            the current object selection
		 * @see ClassDiagramCreationWizard#init(IWorkbench,
		 *      IStructuredSelection)
		 */
		CreationPage(IWorkbench workbench, IStructuredSelection selection) {
			super("classDiagramCreationPage1", selection);
			this.workbench = workbench;
			setTitle("Create a new " + DEFAULT_EXTENSION + " file");
			setDescription("Create a new " + DEFAULT_EXTENSION + " file");
		}

		/*
		 * (non-Javadoc)
		 * 
		 * @see org.eclipse.ui.dialogs.WizardNewFileCreationPage#createControl(org.eclipse.swt.widgets.Composite)
		 */
		public void createControl(Composite parent) {
			super.createControl(parent);
			setFileName("classDiagramExample" + fileCount + DEFAULT_EXTENSION);
			setPageComplete(validatePage());
		}

		private Object createDefaultContent() {
			return new ClassDiagram();
		}

		/**
		 * This method will be invoked, when the "Finish" button is pressed.
		 * 
		 * @see ClassDiagramCreationWizard#performFinish()
		 */
		boolean finish() {
			// create a new file, result != null if successful
			IFile newFile = createNewFile();
			fileCount++;

			// open newly created file in the editor
			IWorkbenchPage page = workbench.getActiveWorkbenchWindow()
					.getActivePage();
			if (newFile != null && page != null) {
				try {
					IDE.openEditor(page, newFile, true);
				} catch (PartInitException e) {
					e.printStackTrace();
					return false;
				}
			}
			return true;
		}

		/*
		 * (non-Javadoc)
		 * 
		 * @see org.eclipse.ui.dialogs.WizardNewFileCreationPage#getInitialContents()
		 */
		protected InputStream getInitialContents() {
			ByteArrayInputStream bais = null;
			try {
				ByteArrayOutputStream baos = new ByteArrayOutputStream();
				ObjectOutputStream oos = new ObjectOutputStream(baos);
				oos.writeObject(createDefaultContent()); // argument must be
															// Serializable
				oos.flush();
				oos.close();
				bais = new ByteArrayInputStream(baos.toByteArray());
			} catch (IOException ioe) {
				ioe.printStackTrace();
			}
			return bais;
		}

		/**
		 * Return true, if the file name entered in this page is valid.
		 */
		private boolean validateFilename() {
			if (getFileName() != null
					&& getFileName().endsWith(DEFAULT_EXTENSION)) {
				return true;
			}
			setErrorMessage("The 'file' name must end with "
					+ DEFAULT_EXTENSION);
			return false;
		}

		/*
		 * (non-Javadoc)
		 * 
		 * @see org.eclipse.ui.dialogs.WizardNewFileCreationPage#validatePage()
		 */
		protected boolean validatePage() {
			return super.validatePage() && validateFilename();
		}
	}
}