ecommons/org.eclipse.statet.ecommons.uimisc/src/org/eclipse/statet/ecommons/ui/viewers/breadcrumb/BreadcrumbItemDetails.java

/*=============================================================================#
 # Copyright (c) 2008, 2021 IBM Corporation and others.
 # 
 # This program and the accompanying materials are made available under the
 # terms of the Eclipse Public License 2.0 which is available at
 # https://www.eclipse.org/legal/epl-2.0.
 # 
 # SPDX-License-Identifier: EPL-2.0
 # 
 # Contributors:
 #     IBM Corporation - org.eclipse.jdt: initial API and implementation
 #     Stephan Wahlbrink <sw@wahlbrink.eu> - initial API and implementation
 #=============================================================================*/

package org.eclipse.statet.ecommons.ui.viewers.breadcrumb;

import org.eclipse.swt.SWT;
import org.eclipse.swt.accessibility.AccessibleAdapter;
import org.eclipse.swt.accessibility.AccessibleEvent;
import org.eclipse.swt.events.FocusEvent;
import org.eclipse.swt.events.FocusListener;
import org.eclipse.swt.events.KeyEvent;
import org.eclipse.swt.events.KeyListener;
import org.eclipse.swt.events.MenuDetectEvent;
import org.eclipse.swt.events.MenuDetectListener;
import org.eclipse.swt.events.MouseEvent;
import org.eclipse.swt.events.MouseListener;
import org.eclipse.swt.events.PaintEvent;
import org.eclipse.swt.events.PaintListener;
import org.eclipse.swt.events.TraverseEvent;
import org.eclipse.swt.events.TraverseListener;
import org.eclipse.swt.graphics.Color;
import org.eclipse.swt.graphics.Image;
import org.eclipse.swt.layout.GridData;
import org.eclipse.swt.layout.GridLayout;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Control;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Label;
import org.eclipse.swt.widgets.Shell;


/**
 * The label and icon part of the breadcrumb item.
 */
class BreadcrumbItemDetails {
	
	
	private final Composite detailComposite;
	
	private final BreadcrumbItem parent;
	
	private final Composite imageComposite;
	private final Label elementImage;
	private final Composite textComposite;
	private final Label elementText;
	
	private boolean textVisible;
	private boolean selected;
	private boolean hasFocus;
	
	
	public BreadcrumbItemDetails(final BreadcrumbItem parent, final Composite parentContainer) {
		this.parent= parent;
		this.textVisible= true;
		
		this.detailComposite= new Composite(parentContainer, SWT.NONE);
		this.detailComposite.setLayoutData(new GridData(SWT.BEGINNING, SWT.CENTER, false, false));
		GridLayout layout= new GridLayout(2, false);
		layout.marginHeight= 0;
		layout.marginWidth= 0;
		layout.horizontalSpacing= 0;
		this.detailComposite.setLayout(layout);
		addElementListener(this.detailComposite);
		
		this.imageComposite= new Composite(this.detailComposite, SWT.NONE);
		this.imageComposite.setLayoutData(new GridData(SWT.BEGINNING, SWT.CENTER, false, false));
		layout= new GridLayout(1, false);
		layout.marginHeight= 1;
		layout.marginWidth= 2;
		this.imageComposite.setLayout(layout);
		this.imageComposite.addPaintListener(new PaintListener() {
			@Override
			public void paintControl(final PaintEvent e) {
				if (BreadcrumbItemDetails.this.hasFocus && !isTextVisible()) {
					e.gc.drawFocus(e.x, e.y, e.width, e.height);
				}
			}
		});
		installFocusComposite(this.imageComposite);
		addElementListener(this.imageComposite);
		
		this.elementImage= new Label(this.imageComposite, SWT.NONE);
		GridData layoutData= new GridData(SWT.BEGINNING, SWT.CENTER, false, false);
		this.elementImage.setLayoutData(layoutData);
		addElementListener(this.elementImage);
		
		this.textComposite= new Composite(this.detailComposite, SWT.NONE);
		this.textComposite.setLayoutData(new GridData(SWT.BEGINNING, SWT.CENTER, false, false));
		layout= new GridLayout(1, false);
		layout.marginHeight= 2;
		layout.marginWidth= 2;
		this.textComposite.setLayout(layout);
		addElementListener(this.textComposite);
		this.textComposite.addPaintListener(new PaintListener() {
			@Override
			public void paintControl(final PaintEvent e) {
				if (BreadcrumbItemDetails.this.hasFocus && isTextVisible()) {
					e.gc.drawFocus(e.x, e.y, e.width, e.height);
				}
			}
		});
		installFocusComposite(this.textComposite);
		addElementListener(this.textComposite);
		
		this.elementText= new Label(this.textComposite, SWT.NONE);
		layoutData= new GridData(SWT.BEGINNING, SWT.CENTER, false, false);
		this.elementText.setLayoutData(layoutData);
		addElementListener(this.elementText);
		
		this.textComposite.getAccessible().addAccessibleListener(new AccessibleAdapter() {
			@Override
			public void getName(final AccessibleEvent e) {
				e.result= BreadcrumbItemDetails.this.elementText.getText();
			}
		});
		this.imageComposite.getAccessible().addAccessibleListener(new AccessibleAdapter() {
			@Override
			public void getName(final AccessibleEvent e) {
				e.result= BreadcrumbItemDetails.this.elementText.getText();
			}
		});
		
		this.detailComposite.setTabList(new Control[] { this.textComposite });
	}
	
	
	/**
	 * Returns whether this element has the keyboard focus.
	 * 
	 * @return true if this element has the keyboard focus.
	 */
	public boolean hasFocus() {
		return this.hasFocus;
	}
	
	/**
	 * Sets the tool tip to the given text.
	 * 
	 * @param text the tool tip
	 */
	public void setToolTip(final String text) {
		if (isTextVisible()) {
			this.elementText.getParent().setToolTipText(text);
			this.elementText.setToolTipText(text);
			
			this.elementImage.setToolTipText(text);
		} else {
			this.elementText.getParent().setToolTipText(null);
			this.elementText.setToolTipText(null);
			
			this.elementImage.setToolTipText(text);
		}
	}
	
	/**
	 * Sets the image to the given image.
	 * 
	 * @param image the image to use
	 */
	public void setImage(final Image image) {
		if (image != this.elementImage.getImage()) {
			this.elementImage.setImage(image);
		}
	}
	
	/**
	 * Sets the text to the given text.
	 * 
	 * @param text the text to use
	 */
	public void setText(String text) {
		if (text == null) {
			text= ""; //$NON-NLS-1$
		}
		if (!text.equals(this.elementText.getText())) {
			this.elementText.setText(text);
		}
	}
	
	/**
	 * Returns the width of this element.
	 * 
	 * @return current width of this element
	 */
	public int getWidth() {
		int result= 2;
		if (this.elementImage.getImage() != null) {
			result+= this.elementImage.computeSize(SWT.DEFAULT, SWT.DEFAULT).x;
		}
		if (this.textVisible && this.elementText.getText().length() > 0) {
			result+= this.elementText.computeSize(SWT.DEFAULT, SWT.DEFAULT).x;
		}
		return result;
	}
	
	public void setTextVisible(final boolean enabled) {
		if (this.textVisible == enabled) {
			return;
		}
		
		this.textVisible= enabled;
		
		final GridData data= (GridData) this.textComposite.getLayoutData();
		data.exclude= !enabled;
		this.textComposite.setVisible(enabled);
		
		if (this.textVisible) {
			this.detailComposite.setTabList(new Control[] { this.textComposite });
		} else {
			this.detailComposite.setTabList(new Control[] { this.imageComposite });
		}
		
		if (this.hasFocus) {
			if (isTextVisible()) {
				this.textComposite.setFocus();
			} else {
				this.imageComposite.setFocus();
			}
		}
		updateSelection();
	}
	
	/**
	 * Tells whether this item shows a text or only an image.
	 * 
	 * @return <code>true</code> if it shows a text and an image, false if it only shows the image
	 */
	public boolean isTextVisible() {
		return this.textVisible;
	}
	
	/**
	 * Sets whether details should be shown.
	 * 
	 * @param visible <code>true</code> if details should be shown
	 */
	public void setVisible(final boolean visible) {
		this.detailComposite.setVisible(visible);
		
		final GridData data= (GridData) this.detailComposite.getLayoutData();
		data.exclude= !visible;
	}
	
	public void setSelected(final boolean selected) {
		if (selected == this.selected) {
			return;
		}
		
		this.selected= selected;
		if (!this.selected) {
			this.hasFocus= false;
		}
		
		updateSelection();
	}
	
	public void setFocus(final boolean enabled) {
		if (enabled == this.hasFocus) {
			return;
		}
		
		this.hasFocus= enabled;
		if (this.hasFocus) {
			if (isTextVisible()) {
				this.textComposite.setFocus();
			} else {
				this.imageComposite.setFocus();
			}
		}
		updateSelection();
	}
	
	private void updateSelection() {
		Color background;
		Color foreground;
		
		if (this.selected && this.hasFocus) {
			background= Display.getDefault().getSystemColor(SWT.COLOR_LIST_SELECTION);
			foreground= Display.getDefault().getSystemColor(SWT.COLOR_LIST_SELECTION_TEXT);
		} else {
			foreground= null;
			background= null;
		}
		
		if (isTextVisible()) {
			this.textComposite.setBackground(background);
			this.elementText.setBackground(background);
			this.elementText.setForeground(foreground);
			
			this.imageComposite.setBackground(null);
			this.elementImage.setBackground(null);
		} else {
			this.imageComposite.setBackground(background);
			this.elementImage.setBackground(background);
			
			this.textComposite.setBackground(null);
			this.elementText.setBackground(null);
			this.elementText.setForeground(null);
		}
		
		this.textComposite.redraw();
		this.imageComposite.redraw();
	}
	
	/**
	 * Install focus and key listeners to the given composite.
	 *
	 * @param composite the composite which may get focus
	 */
	private void installFocusComposite(final Composite composite) {
		composite.addTraverseListener(new TraverseListener() {
			@Override
			public void keyTraversed(final TraverseEvent e) {
				if (e.detail == SWT.TRAVERSE_TAB_NEXT || e.detail == SWT.TRAVERSE_TAB_PREVIOUS) {
					int index= BreadcrumbItemDetails.this.parent.getViewer().getIndexOfItem(BreadcrumbItemDetails.this.parent);
					if (e.detail == SWT.TRAVERSE_TAB_NEXT) {
						index++;
					} else {
						index--;
					}
					
					if (index > 0 && index < BreadcrumbItemDetails.this.parent.getViewer().getItemCount()) {
						BreadcrumbItemDetails.this.parent.getViewer().selectItem(BreadcrumbItemDetails.this.parent.getViewer().getItem(index));
					}
					
					e.doit= true;
				}
			}
		});
		composite.addKeyListener(new KeyListener() {
			
			@Override
			public void keyPressed(final KeyEvent e) {
				final BreadcrumbViewer viewer= BreadcrumbItemDetails.this.parent.getViewer();
				
				switch (e.keyCode) {
					case SWT.ARROW_LEFT:
						if (BreadcrumbItemDetails.this.selected) {
							viewer.doTraverse(false);
							e.doit= false;
						} else {
							viewer.selectItem(BreadcrumbItemDetails.this.parent);
						}
						break;
					case SWT.ARROW_RIGHT:
						if (BreadcrumbItemDetails.this.selected) {
							viewer.doTraverse(true);
							e.doit= false;
						} else {
							viewer.selectItem(BreadcrumbItemDetails.this.parent);
						}
						break;
					case SWT.ARROW_DOWN:
						if (!BreadcrumbItemDetails.this.selected) {
							viewer.selectItem(BreadcrumbItemDetails.this.parent);
						}
						openDropDown();
						e.doit= false;
						break;
					case SWT.KEYPAD_ADD:
						if (!BreadcrumbItemDetails.this.selected) {
							viewer.selectItem(BreadcrumbItemDetails.this.parent);
						}
						openDropDown();
						e.doit= false;
						break;
					case SWT.CR:
						if (!BreadcrumbItemDetails.this.selected) {
							viewer.selectItem(BreadcrumbItemDetails.this.parent);
						}
						viewer.fireOpen();
						break;
					default:
						if (e.character == ' ') {
							if (!BreadcrumbItemDetails.this.selected) {
								viewer.selectItem(BreadcrumbItemDetails.this.parent);
							}
							openDropDown();
							e.doit= false;
						}
						break;
				}
			}
			
			private void openDropDown() {
				final BreadcrumbViewer viewer= BreadcrumbItemDetails.this.parent.getViewer();
				
				final int index= viewer.getIndexOfItem(BreadcrumbItemDetails.this.parent);
				final BreadcrumbItem parent= BreadcrumbItemDetails.this.parent.getViewer().getItem(index - 1);
				
				Shell shell= parent.getDropDownShell();
				if (shell == null) {
					parent.openDropDownMenu();
					shell= parent.getDropDownShell();
				}
				shell.setFocus();
			}
			
			@Override
			public void keyReleased(final KeyEvent e) {
			}
			
		});
		
		composite.addFocusListener(new FocusListener() {
			
			@Override
			public void focusGained(final FocusEvent e) {
				if (!BreadcrumbItemDetails.this.hasFocus) {
					BreadcrumbItemDetails.this.hasFocus= true;
					updateSelection();
				}
			}
			
			@Override
			public void focusLost(final FocusEvent e) {
				if (BreadcrumbItemDetails.this.hasFocus) {
					BreadcrumbItemDetails.this.hasFocus= false;
					updateSelection();
				}
			}
			
		});
	}
	
	/**
	 * Add mouse listeners to the given control.
	 * 
	 * @param control the control to which may be clicked
	 */
	private void addElementListener(final Control control) {
		control.addMouseListener(new MouseListener() {
			
			@Override
			public void mouseDoubleClick(final MouseEvent e) {
			}
			
			@Override
			public void mouseDown(final MouseEvent e) {
				final BreadcrumbViewer viewer= BreadcrumbItemDetails.this.parent.getViewer();
				
				final int parentIndex= viewer.getIndexOfItem(BreadcrumbItemDetails.this.parent) - 1;
				Shell shell= null;
				if (parentIndex >= 0) {//sanity check, must always hold
					final BreadcrumbItem dropDownItem= viewer.getItem(parentIndex);
					shell= dropDownItem.getDropDownShell();
				}
				
				viewer.selectItem(BreadcrumbItemDetails.this.parent);
				if (shell == null && e.button == 1 && e.stateMask == 0) {
					BreadcrumbItemDetails.this.parent.getViewer().fireDoubleClick();
				}
			}
			
			@Override
			public void mouseUp(final MouseEvent e) {
			}
			
		});
		control.addMenuDetectListener(new MenuDetectListener() {
			
			@Override
			public void menuDetected(final MenuDetectEvent e) {
				final BreadcrumbViewer viewer= BreadcrumbItemDetails.this.parent.getViewer();
				viewer.selectItem(BreadcrumbItemDetails.this.parent);
				BreadcrumbItemDetails.this.parent.getViewer().fireMenuDetect(e);
			}
			
		});
	}
	
}