package eu.scasefp7.eclipse.servicecomposition.ui;

import java.util.ArrayList;
import java.util.List;

import org.eclipse.core.resources.IContainer;
import org.eclipse.core.resources.IFile;
import org.eclipse.core.resources.IProject;
import org.eclipse.core.resources.IResource;
import org.eclipse.core.resources.ResourcesPlugin;
import org.eclipse.core.runtime.CoreException;
import org.eclipse.core.runtime.IStatus;
import org.eclipse.core.runtime.Status;
import org.eclipse.jface.viewers.ILabelProvider;
import org.eclipse.jface.viewers.ITreeContentProvider;
import org.eclipse.jface.viewers.Viewer;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Shell;
import org.eclipse.ui.dialogs.ElementTreeSelectionDialog;
import org.eclipse.ui.dialogs.ISelectionStatusValidator;
import org.eclipse.ui.model.WorkbenchLabelProvider;

import eu.scasefp7.eclipse.servicecomposition.Activator;

public class ResourceFileSelectionDialog extends ElementTreeSelectionDialog {

	/**
	 * file extensions
	 */
	private String[] extensions;
	/**
	 * content provider of the dialog
	 */
	private static ITreeContentProvider contentProvider = new ITreeContentProvider() {
		public Object[] getChildren(Object element) {
			if (element instanceof IContainer) {
				try {
					return ((IContainer) element).members();
				} catch (CoreException e) {
				}
			}
			return null;
		}

		public Object getParent(Object element) {
			return ((IResource) element).getParent();
		}

		public boolean hasChildren(Object element) {
			return element instanceof IContainer;
		}

		public Object[] getElements(Object input) {
			return (Object[]) input;
		}

		public void dispose() {
		}

		public void inputChanged(Viewer viewer, Object oldInput, Object newInput) {
		}
	};

	private static final IStatus OK = new Status(IStatus.OK, Activator.PLUGIN_ID, 0, "", null);
	private static final IStatus ERROR = new Status(IStatus.ERROR, Activator.PLUGIN_ID, 0, "", null);

	/*
	 * Validator
	 */
	private ISelectionStatusValidator validator = new ISelectionStatusValidator() {
		public IStatus validate(Object[] selection) {
			return selection.length == 1
					&& selection[0] instanceof IFile
					&& checkExtension(((IFile) selection[0]).getFileExtension()) ? OK
					: ERROR;
		}
	};

	public ResourceFileSelectionDialog(String title, String message,
			String[] type) {
		this(Display.getDefault().getActiveShell(), WorkbenchLabelProvider
				.getDecoratingWorkbenchLabelProvider(), contentProvider);
		this.extensions = type;

		setTitle(title);
		setMessage(message);

		setInput(computeInput());
		setValidator(validator);
	}

	public ResourceFileSelectionDialog(Shell parent,
			ILabelProvider labelProvider, ITreeContentProvider contentProvider) {
		super(parent, labelProvider, contentProvider);
	}

	/*
	 * Show projects
	 */
	private Object[] computeInput() {
		/*
		 * Refresh projects tree.
		 */
		IProject[] projects = ResourcesPlugin.getWorkspace().getRoot()
				.getProjects();
		for (int i = 0; i < projects.length; i++) {
			try {
				projects[i].refreshLocal(IResource.DEPTH_INFINITE, null);
			} catch (CoreException e) {
				e.printStackTrace();
			}
		}

		try {
			ResourcesPlugin.getWorkspace().getRoot()
					.refreshLocal(IResource.DEPTH_ONE, null);
		} catch (CoreException e) {
		}
		List<IProject> openProjects = new ArrayList<IProject>(projects.length);
		for (int i = 0; i < projects.length; i++) {
			if (projects[i].isOpen()) {
				openProjects.add(projects[i]);
			}
		}
		return openProjects.toArray();
	}

	/*
	 * Check file extension
	 */
	private boolean checkExtension(String name) {
		if (name.equals("*")) {
			return true;
		}

		for (int i = 0; i < extensions.length; i++) {
			if (extensions[i].equals(name)) {
				return true;
			}
		}
		return false;
	}
}
