core/plugins/org.eclipse.dltk.debug.ui/src/org/eclipse/dltk/internal/debug/ui/interpreters/LibraryContentProvider.java

/*******************************************************************************
 * Copyright (c) 2006, 2018 IBM Corporation and others.
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License v. 2.0 which is available at
 * http://www.eclipse.org/legal/epl-2.0.
 * 
 * SPDX-License-Identifier: EPL-2.0
 *
 *******************************************************************************/
package org.eclipse.dltk.internal.debug.ui.interpreters;

import java.util.ArrayList;
import java.util.HashSet;
import java.util.Iterator;
import java.util.List;
import java.util.Set;

import org.eclipse.dltk.core.environment.IFileHandle;
import org.eclipse.dltk.launching.EnvironmentVariable;
import org.eclipse.dltk.launching.LibraryLocation;
import org.eclipse.jface.viewers.IStructuredSelection;
import org.eclipse.jface.viewers.ITreeContentProvider;
import org.eclipse.jface.viewers.StructuredSelection;
import org.eclipse.jface.viewers.TreeViewer;
import org.eclipse.jface.viewers.Viewer;

public class LibraryContentProvider implements ITreeContentProvider {

	protected TreeViewer fViewer;

	protected LibraryStandin[] fLibraries = new LibraryStandin[0];
	protected LibraryStandin[] fAllLibraries = new LibraryStandin[0];

	public LibraryContentProvider() {
	}

	@Override
	public void dispose() {
	}

	@Override
	public void inputChanged(Viewer viewer, Object oldInput, Object newInput) {
		fViewer = (TreeViewer) viewer;
	}

	@Override
	public Object[] getElements(Object inputElement) {
		return fLibraries;
	}

	public void setLibraries(LibraryLocation[] libs) {
		if (libs != null) {
			fLibraries = new LibraryStandin[libs.length];
			for (int i = 0; i < libs.length; i++) {
				fLibraries[i] = new LibraryStandin(libs[i]);
			}
		} else {
			fLibraries = new LibraryStandin[0];
		}
		fViewer.refresh();
	}

	public void initialize(IFileHandle file,
			EnvironmentVariable[] environmentVariables,
			boolean restoreDefault) {

	}

	public LibraryLocation[] getLibraries() {
		LibraryLocation[] locations = new LibraryLocation[fLibraries.length];
		for (int i = 0; i < locations.length; i++) {
			locations[i] = fLibraries[i].toLibraryLocation();
		}
		return locations;
	}

	/**
	 * Returns the list of libraries in the given selection. SubElements are
	 * replaced by their parent libraries.
	 */
	private Set<LibraryStandin> getSelectedLibraries(
			IStructuredSelection selection) {
		Set<LibraryStandin> libraries = new HashSet<>();
		for (Iterator<?> iter = selection.iterator(); iter.hasNext();) {
			Object element = iter.next();
			if (element instanceof LibraryStandin) {
				libraries.add((LibraryStandin) element);
			}
		}
		return libraries;
	}

	/**
	 * Move the libraries of the given selection up.
	 */
	public void up(IStructuredSelection selection) {
		Set<LibraryStandin> libraries = getSelectedLibraries(selection);
		for (int i = 0; i < fLibraries.length - 1; i++) {
			if (libraries.contains(fLibraries[i + 1])) {
				LibraryStandin temp = fLibraries[i];
				fLibraries[i] = fLibraries[i + 1];
				fLibraries[i + 1] = temp;
			}
		}
		fViewer.refresh();
		fViewer.setSelection(selection);
	}

	/**
	 * Move the libraries of the given selection down.
	 */
	public void down(IStructuredSelection selection) {
		Set<LibraryStandin> libraries = getSelectedLibraries(selection);
		for (int i = fLibraries.length - 1; i > 0; i--) {
			if (libraries.contains(fLibraries[i - 1])) {
				LibraryStandin temp = fLibraries[i];
				fLibraries[i] = fLibraries[i - 1];
				fLibraries[i - 1] = temp;
			}
		}
		fViewer.refresh();
		fViewer.setSelection(selection);
	}

	/**
	 * Remove the libraries contained in the given selection.
	 */
	public void remove(IStructuredSelection selection) {
		List<LibraryStandin> newLibraries = new ArrayList<>();
		for (int i = 0; i < fLibraries.length; i++) {
			newLibraries.add(fLibraries[i]);
		}
		Iterator<?> iterator = selection.iterator();
		while (iterator.hasNext()) {
			Object element = iterator.next();
			if (element instanceof LibraryStandin) {
				newLibraries.remove(element);
			}
		}
		fLibraries = newLibraries
				.toArray(new LibraryStandin[newLibraries.size()]);
		fViewer.refresh();
	}

	/**
	 * Add the given libraries before the selection, or after the existing
	 * libraries if the selection is empty.
	 */
	public void add(LibraryLocation[] libs, IStructuredSelection selection) {
		List<LibraryStandin> newLibraries = new ArrayList<>(
				fLibraries.length + libs.length);
		for (int i = 0; i < fLibraries.length; i++) {
			newLibraries.add(fLibraries[i]);
		}
		List<LibraryStandin> toAdd = new ArrayList<>(libs.length);
		for (int i = 0; i < libs.length; i++) {
			toAdd.add(new LibraryStandin(libs[i]));
		}
		if (selection.isEmpty()) {
			newLibraries.addAll(toAdd);
		} else {
			Object element = selection.getFirstElement();
			if (element instanceof LibraryStandin) {
				LibraryStandin firstLib = (LibraryStandin) element;
				int index = newLibraries.indexOf(firstLib);
				newLibraries.addAll(index, toAdd);
			} else {
				newLibraries.addAll(toAdd);
			}
		}
		fLibraries = newLibraries
				.toArray(new LibraryStandin[newLibraries.size()]);
		fViewer.refresh();
		fViewer.setSelection(new StructuredSelection(libs), true);
	}

	/**
	 * Returns the standin libraries being edited.
	 *
	 * @return standins
	 */
	public LibraryStandin[] getStandins() {
		return fLibraries;
	}

	@Override
	public Object[] getChildren(Object parentElement) {
		// TODO Auto-generated method stub
		return null;
	}

	@Override
	public Object getParent(Object element) {
		// TODO Auto-generated method stub
		return null;
	}

	@Override
	public boolean hasChildren(Object element) {
		// TODO Auto-generated method stub
		return false;
	}

	public boolean isEnabled(Object lib) {
		return true;
	}

	public boolean canRemove(IStructuredSelection selection) {
		return !selection.isEmpty();
	}

	public void changeEnabled() {
	}

	public boolean canEnable(IStructuredSelection selection) {
		return false;
	}

	public boolean canUp(IStructuredSelection selection) {
		return true;
	}

	public boolean canDown(IStructuredSelection selection) {
		return true;
	}
}