/*******************************************************************************
 * Copyright (c) 2006, 2023 Tom Schindl and others.
 *
 * This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License 2.0
 * which accompanies this distribution, and is available at
 * https://www.eclipse.org/legal/epl-2.0/
 *
 * SPDX-License-Identifier: EPL-2.0
 *
 * Contributors:
 *     Tom Schindl <tom.schindl@bestsolution.at> - initial API and implementation
 *     Florian Potschka <signalrauschen@gmail.com> - Bug 260061
 *     Alexander Ljungberg <siker@norwinter.com> - Bug 260061
 *     Jeanderson Candido <http://jeandersonbc.github.io> - Bug 414565
 *     Lars Vogel <Lars.Vogel@vogella.com> - Bug 475361
 *******************************************************************************/

package org.eclipse.jface.snippets.viewers;

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

import org.eclipse.jface.resource.JFaceResources;
import org.eclipse.jface.util.Util;
import org.eclipse.jface.viewers.CellEditor;
import org.eclipse.jface.viewers.ColumnViewer;
import org.eclipse.jface.viewers.ColumnViewerEditor;
import org.eclipse.jface.viewers.ColumnViewerEditorActivationStrategy;
import org.eclipse.jface.viewers.EditingSupport;
import org.eclipse.jface.viewers.FocusCellOwnerDrawHighlighter;
import org.eclipse.jface.viewers.ITreeContentProvider;
import org.eclipse.jface.viewers.OwnerDrawLabelProvider;
import org.eclipse.jface.viewers.TextCellEditor;
import org.eclipse.jface.viewers.TreeViewer;
import org.eclipse.jface.viewers.TreeViewerColumn;
import org.eclipse.jface.viewers.TreeViewerEditor;
import org.eclipse.jface.viewers.TreeViewerFocusCellManager;
import org.eclipse.jface.viewers.Viewer;
import org.eclipse.jface.viewers.ViewerCell;
import org.eclipse.swt.SWT;
import org.eclipse.swt.graphics.Color;
import org.eclipse.swt.graphics.GC;
import org.eclipse.swt.graphics.Image;
import org.eclipse.swt.graphics.ImageData;
import org.eclipse.swt.graphics.Point;
import org.eclipse.swt.graphics.Rectangle;
import org.eclipse.swt.layout.FillLayout;
import org.eclipse.swt.widgets.Button;
import org.eclipse.swt.widgets.Control;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Event;
import org.eclipse.swt.widgets.Shell;
import org.eclipse.swt.widgets.TableItem;
import org.eclipse.swt.widgets.TreeItem;

/**
 * A simple TreeViewer to demonstrate usage
 */
public class Snippet061FakedNativeCellEditor {

	private static final class MyEditingSupport extends EditingSupport {
		private final TextCellEditor textCellEditor;
		private final TreeViewer viewer;

		private MyEditingSupport(ColumnViewer viewer,
				TextCellEditor textCellEditor, TreeViewer viewer2) {
			super(viewer);
			this.textCellEditor = textCellEditor;
			this.viewer = viewer2;
		}

		@Override
		protected boolean canEdit(Object element) {
			return true;
		}

		@Override
		protected CellEditor getCellEditor(Object element) {
			return textCellEditor;
		}

		@Override
		protected Object getValue(Object element) {
			return ((File) element).counter + "";
		}

		@Override
		protected void setValue(Object element, Object value) {
			((File) element).counter = Integer.parseInt(value.toString());
			viewer.update(element, null);
		}
	}

	private static class MyContentProvider implements ITreeContentProvider {

		@Override
		public Object[] getElements(Object inputElement) {
			return ((File) inputElement).child.toArray();
		}

		@Override
		public void dispose() {
		}

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

		@Override
		public Object[] getChildren(Object parentElement) {
			return getElements(parentElement);
		}

		@Override
		public Object getParent(Object element) {
			if (element == null) {
				return null;
			}
			return ((File) element).parent;
		}

		@Override
		public boolean hasChildren(Object element) {
			return ((File) element).child.size() > 0;
		}

	}

	public abstract static class EmulatedNativeCheckBoxLabelProvider extends
			OwnerDrawLabelProvider {
		private static final String CHECKED_KEY = "CHECKED";
		private static final String UNCHECK_KEY = "UNCHECKED";

		public EmulatedNativeCheckBoxLabelProvider(ColumnViewer viewer) {
			if (JFaceResources.getImageRegistry().getDescriptor(CHECKED_KEY) == null) {
				JFaceResources.getImageRegistry().put(UNCHECK_KEY,
						makeShot(viewer.getControl(), false));
				JFaceResources.getImageRegistry().put(CHECKED_KEY,
						makeShot(viewer.getControl(), true));
			}
		}

		private Image makeShot(Control control, boolean type) {
			// Hopefully no platform uses exactly this color because we'll make
			// it transparent in the image.
			Color greenScreen = new Color(control.getDisplay(), 222, 223, 224);

			Shell shell = new Shell(control.getShell(), SWT.NO_TRIM);

			// otherwise we have a default gray color
			shell.setBackground(greenScreen);

			if (Util.isMac()) {
				Button button2 = new Button(shell, SWT.CHECK);
				Point bsize = button2.computeSize(SWT.DEFAULT, SWT.DEFAULT);

				// otherwise an image is stretched by width
				bsize.x = Math.max(bsize.x - 1, bsize.y - 1);
				bsize.y = Math.max(bsize.x - 1, bsize.y - 1);
				button2.setSize(bsize);
				button2.setLocation(100, 100);
			}

			Button button = new Button(shell, SWT.CHECK);
			button.setBackground(greenScreen);
			button.setSelection(type);

			// otherwise an image is located in a corner
			button.setLocation(1, 1);
			Point bsize = button.computeSize(SWT.DEFAULT, SWT.DEFAULT);

			// otherwise an image is stretched by width
			bsize.x = Math.max(bsize.x - 1, bsize.y - 1);
			bsize.y = Math.max(bsize.x - 1, bsize.y - 1);
			button.setSize(bsize);

			shell.setSize(bsize);

			shell.open();

			GC gc = new GC(shell);
			Image image = new Image(control.getDisplay(), bsize.x, bsize.y);
			gc.copyArea(image, 0, 0);
			gc.dispose();
			shell.close();

			ImageData imageData = image.getImageData();
			imageData.transparentPixel = imageData.palette.getPixel(greenScreen
					.getRGB());

			Image img = new Image(control.getDisplay(), imageData);
			image.dispose();

			return img;
		}

		public Image getImage(Object element) {
			if (isChecked(element)) {
				return JFaceResources.getImageRegistry().get(CHECKED_KEY);
			} else {
				return JFaceResources.getImageRegistry().get(UNCHECK_KEY);
			}
		}

		@Override
		protected void measure(Event event, Object element) {
			event.height = getImage(element).getBounds().height;
		}

		@Override
		protected void paint(Event event, Object element) {

			Image img = getImage(element);

			if (img != null) {
				Rectangle bounds;

				if (event.item instanceof TableItem ti) {
					bounds = ti.getBounds(event.index);
				} else {
					bounds = ((TreeItem) event.item).getBounds(event.index);
				}

				Rectangle imgBounds = img.getBounds();
				bounds.width /= 2;
				bounds.width -= imgBounds.width / 2;
				bounds.height /= 2;
				bounds.height -= imgBounds.height / 2;

				int x = bounds.width > 0 ? bounds.x + bounds.width : bounds.x;
				int y = bounds.height > 0 ? bounds.y + bounds.height : bounds.y;

				if (SWT.getPlatform().equals("carbon")) {
					event.gc.drawImage(img, x + 2, y - 1);
				} else {
					event.gc.drawImage(img, x, y - 1);
				}

			}
		}

		protected abstract boolean isChecked(Object element);
	}

	public Snippet061FakedNativeCellEditor(final Shell shell) {
		final TreeViewer viewer = new TreeViewer(shell, SWT.BORDER
				| SWT.FULL_SELECTION);
		viewer.getTree().setLinesVisible(true);
		viewer.getTree().setBackgroundMode(SWT.INHERIT_DEFAULT);
		viewer.getTree().setHeaderVisible(true);

		FocusCellOwnerDrawHighlighter h = new FocusCellOwnerDrawHighlighter(
				viewer) {

			@Override
			protected Color getSelectedCellBackgroundColorNoFocus(
					ViewerCell cell) {
				return shell.getDisplay().getSystemColor(
						SWT.COLOR_LIST_SELECTION);
			}

			@Override
			protected Color getSelectedCellForegroundColorNoFocus(
					ViewerCell cell) {
				return shell.getDisplay().getSystemColor(
						SWT.COLOR_WIDGET_FOREGROUND);
			}
		};

		TreeViewerFocusCellManager focusCellManager = new TreeViewerFocusCellManager(
				viewer, h);
		ColumnViewerEditorActivationStrategy actSupport = new ColumnViewerEditorActivationStrategy(
				viewer);

		int features = ColumnViewerEditor.TABBING_HORIZONTAL
				| ColumnViewerEditor.TABBING_MOVE_TO_ROW_NEIGHBOR
				| ColumnViewerEditor.TABBING_VERTICAL
				| ColumnViewerEditor.KEYBOARD_ACTIVATION;

		TreeViewerEditor.create(viewer, focusCellManager, actSupport, features);

		final TextCellEditor textCellEditor = new TextCellEditor(
				viewer.getTree());
		final BooleanCellEditor booleanCellEditor = new BooleanCellEditor(
				viewer.getTree());
		booleanCellEditor.setChangeOnActivation(true);

		TreeViewerColumn column = null;

		column = createColumnFor(viewer, SWT.NONE, "File");
		column.setLabelProvider(new OwnerDrawLabelProvider() {

			@Override
			protected void measure(Event event, Object element) {

			}

			@Override
			protected void paint(Event event, Object element) {
				((TreeItem) event.item).setText(element.toString());
			}

		});
		column.setEditingSupport(new MyEditingSupport(viewer, textCellEditor,
				viewer));

		column = createColumnFor(viewer, SWT.CENTER, "Read");
		column.setLabelProvider(new EmulatedNativeCheckBoxLabelProvider(viewer) {

			@Override
			protected boolean isChecked(Object element) {
				return ((File) element).read;
			}

		});
		column.setEditingSupport(new MyEditingSupport(viewer, textCellEditor,
				viewer));
		column = createColumnFor(viewer, SWT.CENTER, "Write");
		column.setLabelProvider(new EmulatedNativeCheckBoxLabelProvider(viewer) {

			@Override
			protected boolean isChecked(Object element) {
				return ((File) element).write;
			}

		});
		column.setEditingSupport(new MyEditingSupport(viewer, textCellEditor,
				viewer));
		column = createColumnFor(viewer, SWT.CENTER, "Execute");
		column.setLabelProvider(new EmulatedNativeCheckBoxLabelProvider(viewer) {

			@Override
			protected boolean isChecked(Object element) {
				return ((File) element).execute;
			}

		});
		column.setEditingSupport(new MyEditingSupport(viewer, textCellEditor,
				viewer));

		viewer.setContentProvider(new MyContentProvider());
		viewer.setInput(createModel());
	}

	private TreeViewerColumn createColumnFor(TreeViewer viewer, int style,
			String label) {
		TreeViewerColumn column = new TreeViewerColumn(viewer, style);
		column.getColumn().setWidth(200);
		column.getColumn().setMoveable(true);
		column.getColumn().setText(label);
		return column;
	}

	private File createModel() {
		File root = new File(0, null);
		root.counter = 0;

		File tmp;
		File subItem;
		for (int i = 1; i < 10; i++) {
			tmp = new File(i, root);
			root.child.add(tmp);
			for (int j = 1; j < i; j++) {
				subItem = new File(j, tmp);
				subItem.child.add(new File(j * 100, subItem));
				tmp.child.add(subItem);
			}
		}

		return root;
	}

	public static void main(String[] args) {
		try {
			Display display = new Display();

			Shell shell = new Shell(display);
			shell.setLayout(new FillLayout());
			new Snippet061FakedNativeCellEditor(shell);
			shell.open();

			while (!shell.isDisposed()) {
				if (!display.readAndDispatch())
					display.sleep();
			}

			display.dispose();
		} catch (Exception e) {
			e.printStackTrace();
		}
	}

	public static class File {
		public File parent;
		public List<File> child = new ArrayList<>();
		public int counter;

		public boolean read;
		public boolean write;
		public boolean execute;

		public File(int counter, File parent) {
			this.parent = parent;
			this.counter = counter;
			this.read = counter % 2 == 0;
			this.write = counter % 3 == 0;
			this.execute = counter % 4 == 0;
		}

		@Override
		public String toString() {
			String rv = "Item ";
			if (parent != null) {
				rv = parent + ".";
			}
			rv += counter;

			return rv;
		}
	}

}