core/plugins/org.eclipse.dltk.ui/src/org/eclipse/dltk/ui/infoviews/AbstractDocumentationView.java - dltk/org.eclipse.dltk.core - Git at Google

 /*******************************************************************************
  * Copyright (c) 2000, 2017 IBM Corporation and others.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
  * which accompanies this distribution, and is available at
  * http://www.eclipse.org/legal/epl-v10.html
  *
  * Contributors:
  *     xored software, Inc. - initial API and Implementation (Andrei Sobolev)
  *     xored software, Inc. - Patch 228846 (Alex Panchenko <alex@xored.com>)
  *******************************************************************************/
 package org.eclipse.dltk.ui.infoviews;

 import java.io.BufferedReader;
 import java.io.IOException;
 import java.io.InputStreamReader;
 import java.io.Reader;
 import java.net.URL;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;

 import org.eclipse.core.runtime.FileLocator;
 import org.eclipse.core.runtime.ListenerList;
 import org.eclipse.core.runtime.Platform;
 import org.eclipse.dltk.core.DLTKLanguageManager;
 import org.eclipse.dltk.core.IDLTKLanguageToolkit;
 import org.eclipse.dltk.core.IMember;
 import org.eclipse.dltk.core.IModelElement;
 import org.eclipse.dltk.core.ISourceModule;
 import org.eclipse.dltk.core.ModelException;
 import org.eclipse.dltk.core.ScriptUtils;
 import org.eclipse.dltk.internal.ui.editor.EditorUtility;
 import org.eclipse.dltk.internal.ui.editor.ScriptEditor;
 import org.eclipse.dltk.internal.ui.text.HTMLTextPresenter;
 import org.eclipse.dltk.ui.DLTKUIPlugin;
 import org.eclipse.dltk.ui.PreferenceConstants;
 import org.eclipse.dltk.ui.ScriptElementLabels;
 import org.eclipse.dltk.ui.documentation.ScriptDocumentationAccess;
 import org.eclipse.dltk.ui.text.completion.HTMLPrinter;
 import org.eclipse.jface.action.Action;
 import org.eclipse.jface.action.IAction;
 import org.eclipse.jface.dialogs.MessageDialogWithToggle;
 import org.eclipse.jface.preference.IPreferenceStore;
 import org.eclipse.jface.resource.JFaceResources;
 import org.eclipse.jface.text.DefaultInformationControl;
 import org.eclipse.jface.text.Document;
 import org.eclipse.jface.text.IDocument;
 import org.eclipse.jface.text.TextPresentation;
 import org.eclipse.jface.text.TextSelection;
 import org.eclipse.jface.viewers.ISelection;
 import org.eclipse.jface.viewers.ISelectionChangedListener;
 import org.eclipse.jface.viewers.ISelectionProvider;
 import org.eclipse.jface.viewers.SelectionChangedEvent;
 import org.eclipse.jface.viewers.StructuredSelection;
 import org.eclipse.jface.window.Window;
 import org.eclipse.swt.SWT;
 import org.eclipse.swt.SWTError;
 import org.eclipse.swt.browser.Browser;
 import org.eclipse.swt.custom.StyledText;
 import org.eclipse.swt.events.ControlAdapter;
 import org.eclipse.swt.events.ControlEvent;
 import org.eclipse.swt.events.SelectionAdapter;
 import org.eclipse.swt.events.SelectionEvent;
 import org.eclipse.swt.graphics.Color;
 import org.eclipse.swt.graphics.FontData;
 import org.eclipse.swt.graphics.RGB;
 import org.eclipse.swt.graphics.Rectangle;
 import org.eclipse.swt.widgets.Composite;
 import org.eclipse.swt.widgets.Control;
 import org.eclipse.ui.IEditorPart;
 import org.eclipse.ui.IWorkbenchPart;
 import org.eclipse.ui.PlatformUI;
 import org.eclipse.ui.texteditor.IAbstractTextEditorHelpContextIds;
 import org.osgi.framework.Bundle;

 /**
  * Abstract view which shows documentation for a given model element.
  */
 public abstract class AbstractDocumentationView extends AbstractInfoView {
 	/**
 	 * Preference key for the preference whether to show a dialog when the SWT
 	 * Browser widget is not available.
 	 *
 	 *
 	 */
 	private static final String DO_NOT_WARN_PREFERENCE_KEY = "AbstractDocumentationView.error.doNotWarn"; //$NON-NLS-1$
 	// see https://bugs.eclipse.org/bugs/show_bug.cgi?id=73558
 	private static final boolean WARNING_DIALOG_ENABLED = false;
 	/** Flags used to render a label in the text widget. */
 	private static final long LABEL_FLAGS = ScriptElementLabels.ALL_FULLY_QUALIFIED
 			| ScriptElementLabels.M_APP_RETURNTYPE
 			| ScriptElementLabels.F_APP_TYPE_SIGNATURE
 			| ScriptElementLabels.M_PARAMETER_TYPES
 			| ScriptElementLabels.M_PARAMETER_NAMES
 			| ScriptElementLabels.M_EXCEPTIONS
 			| ScriptElementLabels.T_TYPE_PARAMETERS;
 	/** The HTML widget. */
 	private Browser fBrowser;
 	/** The text widget. */
 	private StyledText fText;
 	/** The information presenter. */
 	private DefaultInformationControl.IInformationPresenter fPresenter;
 	/** The text presentation. */
 	private TextPresentation fPresentation = new TextPresentation();
 	/** The select all action */
 	private SelectAllAction fSelectAllAction;
 	/** The style sheet (css) */
 	private static String fgStyleSheet;
 	/** The Browser widget */
 	private boolean fIsUsingBrowserWidget;
 	private RGB fBackgroundColorRGB, fForegroundColorRGB;

 	/**
 	 * The Javadoc view's select all action.
 	 */
 	private class SelectAllAction extends Action {
 		/** The control. */
 		private Control fControl;
 		/** The selection provider. */
 		private SelectionProvider fSelectionProvider;

 		/**
 		 * Creates the action.
 		 *
 		 * @param control
 		 *            the widget
 		 * @param selectionProvider
 		 *            the selection provider
 		 */
 		public SelectAllAction(Control control,
 				SelectionProvider selectionProvider) {
 			super("selectAll"); //$NON-NLS-1$
 			fControl = control;
 			fSelectionProvider = selectionProvider;
 			// FIXME: see https://bugs.eclipse.org/bugs/show_bug.cgi?id=63022
 			setEnabled(!fIsUsingBrowserWidget);
 			setText(InfoViewMessages.SelectAllAction_label);
 			setToolTipText(InfoViewMessages.SelectAllAction_tooltip);
 			setDescription(InfoViewMessages.SelectAllAction_description);
 			PlatformUI.getWorkbench().getHelpSystem().setHelp(this,
 					IAbstractTextEditorHelpContextIds.SELECT_ALL_ACTION);
 		}

 		/**
 		 * Selects all in the view.
 		 */
 		@Override
 		public void run() {
 			if (fControl instanceof StyledText)
 				((StyledText) fControl).selectAll();
 			else {
 				// FIXME: see
 				// https://bugs.eclipse.org/bugs/show_bug.cgi?id=63022
 				// ((Browser)fControl).selectAll();
 				if (fSelectionProvider != null)
 					fSelectionProvider.fireSelectionChanged();
 			}
 		}
 	}

 	/**
 	 * The Javadoc view's selection provider.
 	 */
 	private static class SelectionProvider implements ISelectionProvider {
 		/** The selection changed listeners. */
 		private ListenerList<ISelectionChangedListener> fListeners = new ListenerList<>(
 				ListenerList.IDENTITY);
 		/** The widget. */
 		private Control fControl;

 		/**
 		 * Creates a new selection provider.
 		 *
 		 * @param control
 		 *            the widget
 		 */
 		public SelectionProvider(Control control) {
 			fControl = control;
 			if (fControl instanceof StyledText) {
 				((StyledText) fControl)
 						.addSelectionListener(new SelectionAdapter() {
 							@Override
 							public void widgetSelected(SelectionEvent e) {
 								fireSelectionChanged();
 							}
 						});
 			} else {
 				// FIXME: see
 				// https://bugs.eclipse.org/bugs/show_bug.cgi?id=63022
 				// ((Browser)fControl).addSelectionListener(new
 				// SelectionAdapter() {
 				// public void widgetSelected(SelectionEvent e) {
 				// fireSelectionChanged();
 				// }
 				// });
 			}
 		}

 		/**
 		 * Sends a selection changed event to all listeners.
 		 */
 		public void fireSelectionChanged() {
 			ISelection selection = getSelection();
 			SelectionChangedEvent event = new SelectionChangedEvent(this,
 					selection);
 			for (ISelectionChangedListener listener : fListeners)
 				listener.selectionChanged(event);
 		}

 		@Override
 		public void addSelectionChangedListener(
 				ISelectionChangedListener listener) {
 			fListeners.add(listener);
 		}

 		@Override
 		public ISelection getSelection() {
 			if (fControl instanceof StyledText) {
 				IDocument document = new Document(
 						((StyledText) fControl).getSelectionText());
 				return new TextSelection(document, 0, document.getLength());
 			} else {
 				// FIXME: see
 				// https://bugs.eclipse.org/bugs/show_bug.cgi?id=63022
 				return StructuredSelection.EMPTY;
 			}
 		}

 		@Override
 		public void removeSelectionChangedListener(
 				ISelectionChangedListener listener) {
 			fListeners.remove(listener);
 		}

 		@Override
 		public void setSelection(ISelection selection) {
 			// not supported
 		}
 	}

 	@Override
 	protected void internalCreatePartControl(Composite parent) {
 		try {
 			fBrowser = new Browser(parent, SWT.NONE);
 			fIsUsingBrowserWidget = true;
 		} catch (SWTError er) {
 			/*
 			 * The Browser widget throws an SWTError if it fails to instantiate
 			 * properly. Application code should catch this SWTError and disable
 			 * any feature requiring the Browser widget. Platform requirements
 			 * for the SWT Browser widget are available from the SWT FAQ web
 			 * site.
 			 */
 			IPreferenceStore store = this.getPreferenceStore();// JavaPlugin.getDefault().getPreferenceStore();
 			boolean doNotWarn = store.getBoolean(DO_NOT_WARN_PREFERENCE_KEY);
 			if (WARNING_DIALOG_ENABLED && !doNotWarn) {
 				String title = InfoViewMessages.ScriptdocView_error_noBrowser_title;
 				String message = InfoViewMessages.ScriptdocView_error_noBrowser_message;
 				String toggleMessage = InfoViewMessages.ScriptdocView_error_noBrowser_doNotWarn;
 				MessageDialogWithToggle dialog = MessageDialogWithToggle
 						.openError(parent.getShell(), title, message,
 								toggleMessage, false, null, null);
 				if (dialog.getReturnCode() == Window.OK)
 					store.setValue(DO_NOT_WARN_PREFERENCE_KEY,
 							dialog.getToggleState());
 			}
 			fIsUsingBrowserWidget = false;
 		}
 		if (!fIsUsingBrowserWidget) {
 			fText = new StyledText(parent, SWT.V_SCROLL | SWT.H_SCROLL);
 			fText.setEditable(false);
 			fPresenter = new HTMLTextPresenter(false);
 			fText.addControlListener(new ControlAdapter() {
 				@Override
 				public void controlResized(ControlEvent e) {
 					setInput(fText.getText());
 				}
 			});
 		}
 		initStyleSheet();
 		getViewSite().setSelectionProvider(new SelectionProvider(getControl()));
 	}

 	protected abstract IPreferenceStore getPreferenceStore();

 	protected abstract String getNature();

 	private static void initStyleSheet() {
 		Bundle bundle = Platform.getBundle(DLTKUIPlugin.getPluginId());
 		URL styleSheetURL = bundle.getEntry("/DocumentationViewStyleSheet.css"); //$NON-NLS-1$
 		if (styleSheetURL == null)
 			return;
 		try {
 			styleSheetURL = FileLocator.toFileURL(styleSheetURL);
 			BufferedReader reader = new BufferedReader(
 					new InputStreamReader(styleSheetURL.openStream()));
 			StringBuffer buffer = new StringBuffer(200);
 			String line = reader.readLine();
 			while (line != null) {
 				buffer.append(line);
 				buffer.append('\n');
 				line = reader.readLine();
 			}
 			FontData fontData = JFaceResources.getFontRegistry().getFontData(
 					PreferenceConstants.APPEARANCE_DOCUMENTATION_FONT)[0];
 			fgStyleSheet = org.eclipse.dltk.ui.text.completion.HTMLPrinter
 					.convertTopLevelFont(buffer.toString(), fontData);
 		} catch (IOException ex) {
 			DLTKUIPlugin.log(ex);
 		}
 	}

 	@Override
 	protected void createActions() {
 		super.createActions();
 		fSelectAllAction = new SelectAllAction(getControl(),
 				(SelectionProvider) getSelectionProvider());
 	}

 	@Override
 	protected IAction getSelectAllAction() {
 		// FIXME: see https://bugs.eclipse.org/bugs/show_bug.cgi?id=63022
 		if (fIsUsingBrowserWidget)
 			return null;
 		return fSelectAllAction;
 	}

 	@Override
 	protected IAction getCopyToClipboardAction() {
 		// FIXME: see https://bugs.eclipse.org/bugs/show_bug.cgi?id=63022
 		if (fIsUsingBrowserWidget)
 			return null;
 		return super.getCopyToClipboardAction();
 	}

 	@Override
 	protected void setForeground(Color color) {
 		getControl().setForeground(color);
 		fForegroundColorRGB = color.getRGB();
 	}

 	@Override
 	protected void setBackground(Color color) {
 		getControl().setBackground(color);
 		// Apply style sheet
 		fBackgroundColorRGB = color.getRGB();
 		if (getInput() == null) {
 			StringBuffer buffer = new StringBuffer();
 			HTMLPrinter.insertPageProlog(buffer, 0, fBackgroundColorRGB,
 					fForegroundColorRGB, fgStyleSheet);
 			setInput(buffer.toString());
 		} else {
 			setInput(computeInput(getInput()));
 		}
 	}

 	@Override
 	protected String getBackgroundColorKey() {
 		return "org.eclipse.dltk.ui.ScriptdocView.backgroundColor"; //$NON-NLS-1$
 	}

 	@Override
 	protected void internalDispose() {
 		fText = null;
 		fBrowser = null;
 	}

 	@Override
 	public void setFocus() {
 		getControl().setFocus();
 	}

 	@Override
 	protected Object computeInput(Object input) {
 		if (getControl() != null) {
 			if (input instanceof KeywordInput) {
 				return getScriptdocHtml((KeywordInput) input);
 			} else if (input instanceof ModelElementArray) {
 				final ModelElementArray array = (ModelElementArray) input;
 				return getScriptdocHtmlDetailed(array.getElements());
 			} else if (input instanceof IModelElement) {
 				final IModelElement je = (IModelElement) input;
 				switch (je.getElementType()) {
 				case IModelElement.SOURCE_MODULE:
 					try {
 						final ISourceModule module = (ISourceModule) je;
 						return getScriptdocHtmlList(module.getChildren());
 					} catch (ModelException ex) {
 						return null;
 					}
 				default:
 					return getScriptdocHtml(je);
 				}
 			}
 		}
 		return null;
 	}

 	@Override
 	protected void setInput(Object input) {
 		String javadocHtml = (String) input;
 		if (fIsUsingBrowserWidget) {
 			if (javadocHtml != null && javadocHtml.length() > 0) {
 				boolean RTL = (getSite().getShell().getStyle()
 						& SWT.RIGHT_TO_LEFT) != 0;
 				if (RTL) {
 					StringBuffer buffer = new StringBuffer(javadocHtml);
 					HTMLPrinter.insertStyles(buffer,
 							new String[] { "direction:rtl" }); //$NON-NLS-1$
 					javadocHtml = buffer.toString();
 				}
 			}
 			fBrowser.setText(javadocHtml);
 		} else {
 			fPresentation.clear();
 			Rectangle size = fText.getClientArea();
 			try {
 				javadocHtml = ((DefaultInformationControl.IInformationPresenterExtension) fPresenter)
 						.updatePresentation(getSite().getShell(), javadocHtml,
 								fPresentation, size.width, size.height);
 			} catch (IllegalArgumentException ex) {
 				// the javadoc might no longer be valid
 				return;
 			}
 			fText.setText(javadocHtml);
 			TextPresentation.applyTextPresentation(fPresentation, fText);
 		}
 	}

 	/**
 	 * Returns the doc in HTML format.
 	 *
 	 * @param result
 	 *            the Script elements for which to get the Javadoc
 	 * @return a string with the Javadoc in HTML format.
 	 */
 	private String getScriptdocHtml(KeywordInput keyword) {
 		StringBuffer buffer = new StringBuffer();
 		try {
 			Reader reader = ScriptDocumentationAccess.getKeywordDocumentation(
 					getNature(), keyword.getContext(), keyword.getValue());
 			if (reader != null) {
 				HTMLPrinter.addParagraph(buffer, reader);
 			}
 		} catch (ModelException ex) {
 			DLTKUIPlugin.log(ex);
 			return null;
 		}
 		if (buffer.length() > 0) {
 			HTMLPrinter.insertPageProlog(buffer, 0, fgStyleSheet);
 			HTMLPrinter.addPageEpilog(buffer);
 			return buffer.toString();
 		}
 		return null;
 	}

 	/**
 	 * Returns the Javadoc in HTML format.
 	 *
 	 * @param result
 	 *            the Script elements for which to get the Javadoc
 	 * @return a string with the Javadoc in HTML format.
 	 */
 	private String getScriptdocHtmlDetailed(Object[] result) {
 		final StringBuffer buffer = new StringBuffer();
 		final List<String> nodocs = new ArrayList<String>();
 		for (int i = 0; i < result.length; i++) {
 			final Object member = result[i];
 			Reader reader = ScriptDocumentationAccess
 					.getHTMLContentReader(getNature(), member, true, true);
 			if (reader != null) {
 				buffer.append("<b>"); //$NON-NLS-1$
 				buffer.append(getInfoText(member));
 				buffer.append("</b>"); //$NON-NLS-1$
 				HTMLPrinter.addParagraph(buffer, reader);
 			} else {
 				if (member instanceof IModelElement) {
 					nodocs.add(ScriptElementLabels.getDefault().getElementLabel(
 							(IModelElement) member,
 							LABEL_FLAGS | ScriptElementLabels.APPEND_FILE));
 				} else {
 					// TODO
 				}
 			}
 		}
 		if (!nodocs.isEmpty()) {
 			Collections.sort(nodocs);
 			HTMLPrinter.addParagraph(buffer,
 					InfoViewMessages.ScriptdocView_noAttachedInformationHeader);
 			HTMLPrinter.startBulletList(buffer);
 			for (String s : nodocs) {
 				HTMLPrinter.addBullet(buffer, s);
 			}
 			HTMLPrinter.endBulletList(buffer);
 		}
 		return addPrologeEpilog(buffer);
 	}

 	/**
 	 * Returns the Javadoc in HTML format.
 	 *
 	 * @param result
 	 *            the Script elements for which to get the Javadoc
 	 * @return a string with the Javadoc in HTML format.
 	 */
 	private String getScriptdocHtmlList(IModelElement[] result) {
 		final StringBuffer buffer = new StringBuffer();
 		HTMLPrinter.startBulletList(buffer);
 		for (int i = 0; i < result.length; i++) {
 			final IModelElement curr = result[i];
 			if (curr instanceof IMember) {
 				final IMember member = (IMember) curr;
 				HTMLPrinter.addBullet(buffer, getInfoText(member));
 			}
 		}
 		HTMLPrinter.endBulletList(buffer);
 		return addPrologeEpilog(buffer);
 	}

 	/**
 	 * Returns the Javadoc in HTML format.
 	 *
 	 * @param result
 	 *            the Script elements for which to get the Javadoc
 	 * @return a string with the Javadoc in HTML format.
 	 */
 	private String getScriptdocHtml(IModelElement curr) {
 		StringBuffer buffer = new StringBuffer();
 		if (curr instanceof IMember) {
 			IMember member = (IMember) curr;
 			// HTMLPrinter.addSmallHeader(buffer, getInfoText(member));
 			Reader reader = ScriptDocumentationAccess
 					.getHTMLContentReader(getNature(), member, true, true);
 			if (reader != null) {
 				HTMLPrinter.addParagraph(buffer, reader);
 			} else {
 				// Provide hint why there's no Javadoc
 				HTMLPrinter.addParagraph(buffer,
 						InfoViewMessages.ScriptdocView_noAttachedInformation);
 			}
 		}
 		return addPrologeEpilog(buffer);
 	}

 	private String addPrologeEpilog(StringBuffer buffer) {
 		if (buffer.length() > 0) {
 			HTMLPrinter.insertPageProlog(buffer, 0, fBackgroundColorRGB,
 					fForegroundColorRGB, fgStyleSheet);
 			HTMLPrinter.addPageEpilog(buffer);
 			return buffer.toString();
 		}
 		return null;
 	}

 	/**
 	 * The method is overridden to compare {@link ScriptEditor} nature with the
 	 * nature of this view.
 	 *
 	 * @see org.eclipse.dltk.ui.infoviews.AbstractInfoView#isValidWorkbenchPart(org.eclipse.ui.IWorkbenchPart)
 	 */
 	@Override
 	protected boolean isValidWorkbenchPart(IWorkbenchPart part) {
 		if (part instanceof IEditorPart) {
 			final IEditorPart editor = (IEditorPart) part;
 			final String editorNature = ScriptUtils.getNatureId(editor);
 			if (editorNature != null) {
 				return editorNature.equals(getNature());
 			}
 			ISourceModule sourceModule = EditorUtility
 					.getEditorInputModelElement(editor, false);
 			if (sourceModule != null) {
 				final IDLTKLanguageToolkit toolkit = DLTKLanguageManager
 						.getLanguageToolkit(sourceModule);
 				return toolkit != null
 						&& toolkit.getNatureId().equals(getNature());
 			}
 		}
 		return false;
 	}

 	/**
 	 * Gets the label for the given member.
 	 *
 	 * @param member
 	 *            the Script member
 	 * @return a string containing the member's label
 	 */
 	private String getInfoText(Object member) {
 		if (member instanceof IModelElement) {
 			return ScriptElementLabels.getDefault()
 					.getElementLabel((IModelElement) member, LABEL_FLAGS);
 		} else {
 			// TODO
 			return null;
 		}
 	}

 	@Override
 	protected Control getControl() {
 		if (fIsUsingBrowserWidget)
 			return fBrowser;
 		else
 			return fText;
 	}

 	@Override
 	protected String getHelpContextId() {
 		// return IJavaHelpContextIds.JAVADOC_VIEW;
 		// TODO: add help support here
 		return ""; //$NON-NLS-1$
 	}
 }
	/*******************************************************************************
	* Copyright (c) 2000, 2017 IBM Corporation and others.
	* All rights reserved. This program and the accompanying materials
	* are made available under the terms of the Eclipse Public License v1.0
	* which accompanies this distribution, and is available at
	* http://www.eclipse.org/legal/epl-v10.html
	*
	* Contributors:
	* xored software, Inc. - initial API and Implementation (Andrei Sobolev)
	* xored software, Inc. - Patch 228846 (Alex Panchenko <alex@xored.com>)
	*******************************************************************************/
	package org.eclipse.dltk.ui.infoviews;

	import java.io.BufferedReader;
	import java.io.IOException;
	import java.io.InputStreamReader;
	import java.io.Reader;
	import java.net.URL;
	import java.util.ArrayList;
	import java.util.Collections;
	import java.util.List;

	import org.eclipse.core.runtime.FileLocator;
	import org.eclipse.core.runtime.ListenerList;
	import org.eclipse.core.runtime.Platform;
	import org.eclipse.dltk.core.DLTKLanguageManager;
	import org.eclipse.dltk.core.IDLTKLanguageToolkit;
	import org.eclipse.dltk.core.IMember;
	import org.eclipse.dltk.core.IModelElement;
	import org.eclipse.dltk.core.ISourceModule;
	import org.eclipse.dltk.core.ModelException;
	import org.eclipse.dltk.core.ScriptUtils;
	import org.eclipse.dltk.internal.ui.editor.EditorUtility;
	import org.eclipse.dltk.internal.ui.editor.ScriptEditor;
	import org.eclipse.dltk.internal.ui.text.HTMLTextPresenter;
	import org.eclipse.dltk.ui.DLTKUIPlugin;
	import org.eclipse.dltk.ui.PreferenceConstants;
	import org.eclipse.dltk.ui.ScriptElementLabels;
	import org.eclipse.dltk.ui.documentation.ScriptDocumentationAccess;
	import org.eclipse.dltk.ui.text.completion.HTMLPrinter;
	import org.eclipse.jface.action.Action;
	import org.eclipse.jface.action.IAction;
	import org.eclipse.jface.dialogs.MessageDialogWithToggle;
	import org.eclipse.jface.preference.IPreferenceStore;
	import org.eclipse.jface.resource.JFaceResources;
	import org.eclipse.jface.text.DefaultInformationControl;
	import org.eclipse.jface.text.Document;
	import org.eclipse.jface.text.IDocument;
	import org.eclipse.jface.text.TextPresentation;
	import org.eclipse.jface.text.TextSelection;
	import org.eclipse.jface.viewers.ISelection;
	import org.eclipse.jface.viewers.ISelectionChangedListener;
	import org.eclipse.jface.viewers.ISelectionProvider;
	import org.eclipse.jface.viewers.SelectionChangedEvent;
	import org.eclipse.jface.viewers.StructuredSelection;
	import org.eclipse.jface.window.Window;
	import org.eclipse.swt.SWT;
	import org.eclipse.swt.SWTError;
	import org.eclipse.swt.browser.Browser;
	import org.eclipse.swt.custom.StyledText;
	import org.eclipse.swt.events.ControlAdapter;
	import org.eclipse.swt.events.ControlEvent;
	import org.eclipse.swt.events.SelectionAdapter;
	import org.eclipse.swt.events.SelectionEvent;
	import org.eclipse.swt.graphics.Color;
	import org.eclipse.swt.graphics.FontData;
	import org.eclipse.swt.graphics.RGB;
	import org.eclipse.swt.graphics.Rectangle;
	import org.eclipse.swt.widgets.Composite;
	import org.eclipse.swt.widgets.Control;
	import org.eclipse.ui.IEditorPart;
	import org.eclipse.ui.IWorkbenchPart;
	import org.eclipse.ui.PlatformUI;
	import org.eclipse.ui.texteditor.IAbstractTextEditorHelpContextIds;
	import org.osgi.framework.Bundle;

	/**
	* Abstract view which shows documentation for a given model element.
	*/
	public abstract class AbstractDocumentationView extends AbstractInfoView {
	/**
	* Preference key for the preference whether to show a dialog when the SWT
	* Browser widget is not available.
	*
	*
	*/
	private static final String DO_NOT_WARN_PREFERENCE_KEY = "AbstractDocumentationView.error.doNotWarn"; //$NON-NLS-1$
	// see https://bugs.eclipse.org/bugs/show_bug.cgi?id=73558
	private static final boolean WARNING_DIALOG_ENABLED = false;
	/** Flags used to render a label in the text widget. */
	private static final long LABEL_FLAGS = ScriptElementLabels.ALL_FULLY_QUALIFIED
	\| ScriptElementLabels.M_APP_RETURNTYPE
	\| ScriptElementLabels.F_APP_TYPE_SIGNATURE
	\| ScriptElementLabels.M_PARAMETER_TYPES
	\| ScriptElementLabels.M_PARAMETER_NAMES
	\| ScriptElementLabels.M_EXCEPTIONS
	\| ScriptElementLabels.T_TYPE_PARAMETERS;
	/** The HTML widget. */
	private Browser fBrowser;
	/** The text widget. */
	private StyledText fText;
	/** The information presenter. */
	private DefaultInformationControl.IInformationPresenter fPresenter;
	/** The text presentation. */
	private TextPresentation fPresentation = new TextPresentation();
	/** The select all action */
	private SelectAllAction fSelectAllAction;
	/** The style sheet (css) */
	private static String fgStyleSheet;
	/** The Browser widget */
	private boolean fIsUsingBrowserWidget;
	private RGB fBackgroundColorRGB, fForegroundColorRGB;

	/**
	* The Javadoc view's select all action.
	*/
	private class SelectAllAction extends Action {
	/** The control. */
	private Control fControl;
	/** The selection provider. */
	private SelectionProvider fSelectionProvider;

	/**
	* Creates the action.
	*
	* @param control
	* the widget
	* @param selectionProvider
	* the selection provider
	*/
	public SelectAllAction(Control control,
	SelectionProvider selectionProvider) {
	super("selectAll"); //$NON-NLS-1$
	fControl = control;
	fSelectionProvider = selectionProvider;
	// FIXME: see https://bugs.eclipse.org/bugs/show_bug.cgi?id=63022
	setEnabled(!fIsUsingBrowserWidget);
	setText(InfoViewMessages.SelectAllAction_label);
	setToolTipText(InfoViewMessages.SelectAllAction_tooltip);
	setDescription(InfoViewMessages.SelectAllAction_description);
	PlatformUI.getWorkbench().getHelpSystem().setHelp(this,
	IAbstractTextEditorHelpContextIds.SELECT_ALL_ACTION);
	}

	/**
	* Selects all in the view.
	*/
	@Override
	public void run() {
	if (fControl instanceof StyledText)
	((StyledText) fControl).selectAll();
	else {
	// FIXME: see
	// https://bugs.eclipse.org/bugs/show_bug.cgi?id=63022
	// ((Browser)fControl).selectAll();
	if (fSelectionProvider != null)
	fSelectionProvider.fireSelectionChanged();
	}
	}
	}

	/**
	* The Javadoc view's selection provider.
	*/
	private static class SelectionProvider implements ISelectionProvider {
	/** The selection changed listeners. */
	private ListenerList<ISelectionChangedListener> fListeners = new ListenerList<>(
	ListenerList.IDENTITY);
	/** The widget. */
	private Control fControl;

	/**
	* Creates a new selection provider.
	*
	* @param control
	* the widget
	*/
	public SelectionProvider(Control control) {
	fControl = control;
	if (fControl instanceof StyledText) {
	((StyledText) fControl)
	.addSelectionListener(new SelectionAdapter() {
	@Override
	public void widgetSelected(SelectionEvent e) {
	fireSelectionChanged();
	}
	});
	} else {
	// FIXME: see
	// https://bugs.eclipse.org/bugs/show_bug.cgi?id=63022
	// ((Browser)fControl).addSelectionListener(new
	// SelectionAdapter() {
	// public void widgetSelected(SelectionEvent e) {
	// fireSelectionChanged();
	// }
	// });
	}
	}

	/**
	* Sends a selection changed event to all listeners.
	*/
	public void fireSelectionChanged() {
	ISelection selection = getSelection();
	SelectionChangedEvent event = new SelectionChangedEvent(this,
	selection);
	for (ISelectionChangedListener listener : fListeners)
	listener.selectionChanged(event);
	}

	@Override
	public void addSelectionChangedListener(
	ISelectionChangedListener listener) {
	fListeners.add(listener);
	}

	@Override
	public ISelection getSelection() {
	if (fControl instanceof StyledText) {
	IDocument document = new Document(
	((StyledText) fControl).getSelectionText());
	return new TextSelection(document, 0, document.getLength());
	} else {
	// FIXME: see
	// https://bugs.eclipse.org/bugs/show_bug.cgi?id=63022
	return StructuredSelection.EMPTY;
	}
	}

	@Override
	public void removeSelectionChangedListener(
	ISelectionChangedListener listener) {
	fListeners.remove(listener);
	}

	@Override
	public void setSelection(ISelection selection) {
	// not supported
	}
	}

	@Override
	protected void internalCreatePartControl(Composite parent) {
	try {
	fBrowser = new Browser(parent, SWT.NONE);
	fIsUsingBrowserWidget = true;
	} catch (SWTError er) {
	/*
	* The Browser widget throws an SWTError if it fails to instantiate
	* properly. Application code should catch this SWTError and disable
	* any feature requiring the Browser widget. Platform requirements
	* for the SWT Browser widget are available from the SWT FAQ web
	* site.
	*/
	IPreferenceStore store = this.getPreferenceStore();// JavaPlugin.getDefault().getPreferenceStore();
	boolean doNotWarn = store.getBoolean(DO_NOT_WARN_PREFERENCE_KEY);
	if (WARNING_DIALOG_ENABLED && !doNotWarn) {
	String title = InfoViewMessages.ScriptdocView_error_noBrowser_title;
	String message = InfoViewMessages.ScriptdocView_error_noBrowser_message;
	String toggleMessage = InfoViewMessages.ScriptdocView_error_noBrowser_doNotWarn;
	MessageDialogWithToggle dialog = MessageDialogWithToggle
	.openError(parent.getShell(), title, message,
	toggleMessage, false, null, null);
	if (dialog.getReturnCode() == Window.OK)
	store.setValue(DO_NOT_WARN_PREFERENCE_KEY,
	dialog.getToggleState());
	}
	fIsUsingBrowserWidget = false;
	}
	if (!fIsUsingBrowserWidget) {
	fText = new StyledText(parent, SWT.V_SCROLL \| SWT.H_SCROLL);
	fText.setEditable(false);
	fPresenter = new HTMLTextPresenter(false);
	fText.addControlListener(new ControlAdapter() {
	@Override
	public void controlResized(ControlEvent e) {
	setInput(fText.getText());
	}
	});
	}
	initStyleSheet();
	getViewSite().setSelectionProvider(new SelectionProvider(getControl()));
	}

	protected abstract IPreferenceStore getPreferenceStore();

	protected abstract String getNature();

	private static void initStyleSheet() {
	Bundle bundle = Platform.getBundle(DLTKUIPlugin.getPluginId());
	URL styleSheetURL = bundle.getEntry("/DocumentationViewStyleSheet.css"); //$NON-NLS-1$
	if (styleSheetURL == null)
	return;
	try {
	styleSheetURL = FileLocator.toFileURL(styleSheetURL);
	BufferedReader reader = new BufferedReader(
	new InputStreamReader(styleSheetURL.openStream()));
	StringBuffer buffer = new StringBuffer(200);
	String line = reader.readLine();
	while (line != null) {
	buffer.append(line);
	buffer.append('\n');
	line = reader.readLine();
	}
	FontData fontData = JFaceResources.getFontRegistry().getFontData(
	PreferenceConstants.APPEARANCE_DOCUMENTATION_FONT)[0];
	fgStyleSheet = org.eclipse.dltk.ui.text.completion.HTMLPrinter
	.convertTopLevelFont(buffer.toString(), fontData);
	} catch (IOException ex) {
	DLTKUIPlugin.log(ex);
	}
	}

	@Override
	protected void createActions() {
	super.createActions();
	fSelectAllAction = new SelectAllAction(getControl(),
	(SelectionProvider) getSelectionProvider());
	}

	@Override
	protected IAction getSelectAllAction() {
	// FIXME: see https://bugs.eclipse.org/bugs/show_bug.cgi?id=63022
	if (fIsUsingBrowserWidget)
	return null;
	return fSelectAllAction;
	}

	@Override
	protected IAction getCopyToClipboardAction() {
	// FIXME: see https://bugs.eclipse.org/bugs/show_bug.cgi?id=63022
	if (fIsUsingBrowserWidget)
	return null;
	return super.getCopyToClipboardAction();
	}

	@Override
	protected void setForeground(Color color) {
	getControl().setForeground(color);
	fForegroundColorRGB = color.getRGB();
	}

	@Override
	protected void setBackground(Color color) {
	getControl().setBackground(color);
	// Apply style sheet
	fBackgroundColorRGB = color.getRGB();
	if (getInput() == null) {
	StringBuffer buffer = new StringBuffer();
	HTMLPrinter.insertPageProlog(buffer, 0, fBackgroundColorRGB,
	fForegroundColorRGB, fgStyleSheet);
	setInput(buffer.toString());
	} else {
	setInput(computeInput(getInput()));
	}
	}

	@Override
	protected String getBackgroundColorKey() {
	return "org.eclipse.dltk.ui.ScriptdocView.backgroundColor"; //$NON-NLS-1$
	}

	@Override
	protected void internalDispose() {
	fText = null;
	fBrowser = null;
	}

	@Override
	public void setFocus() {
	getControl().setFocus();
	}

	@Override
	protected Object computeInput(Object input) {
	if (getControl() != null) {
	if (input instanceof KeywordInput) {
	return getScriptdocHtml((KeywordInput) input);
	} else if (input instanceof ModelElementArray) {
	final ModelElementArray array = (ModelElementArray) input;
	return getScriptdocHtmlDetailed(array.getElements());
	} else if (input instanceof IModelElement) {
	final IModelElement je = (IModelElement) input;
	switch (je.getElementType()) {
	case IModelElement.SOURCE_MODULE:
	try {
	final ISourceModule module = (ISourceModule) je;
	return getScriptdocHtmlList(module.getChildren());
	} catch (ModelException ex) {
	return null;
	}
	default:
	return getScriptdocHtml(je);
	}
	}
	}
	return null;
	}

	@Override
	protected void setInput(Object input) {
	String javadocHtml = (String) input;
	if (fIsUsingBrowserWidget) {
	if (javadocHtml != null && javadocHtml.length() > 0) {
	boolean RTL = (getSite().getShell().getStyle()
	& SWT.RIGHT_TO_LEFT) != 0;
	if (RTL) {
	StringBuffer buffer = new StringBuffer(javadocHtml);
	HTMLPrinter.insertStyles(buffer,
	new String[] { "direction:rtl" }); //$NON-NLS-1$
	javadocHtml = buffer.toString();
	}
	}
	fBrowser.setText(javadocHtml);
	} else {
	fPresentation.clear();
	Rectangle size = fText.getClientArea();
	try {
	javadocHtml = ((DefaultInformationControl.IInformationPresenterExtension) fPresenter)
	.updatePresentation(getSite().getShell(), javadocHtml,
	fPresentation, size.width, size.height);
	} catch (IllegalArgumentException ex) {
	// the javadoc might no longer be valid
	return;
	}
	fText.setText(javadocHtml);
	TextPresentation.applyTextPresentation(fPresentation, fText);
	}
	}

	/**
	* Returns the doc in HTML format.
	*
	* @param result
	* the Script elements for which to get the Javadoc
	* @return a string with the Javadoc in HTML format.
	*/
	private String getScriptdocHtml(KeywordInput keyword) {
	StringBuffer buffer = new StringBuffer();
	try {
	Reader reader = ScriptDocumentationAccess.getKeywordDocumentation(
	getNature(), keyword.getContext(), keyword.getValue());
	if (reader != null) {
	HTMLPrinter.addParagraph(buffer, reader);
	}
	} catch (ModelException ex) {
	DLTKUIPlugin.log(ex);
	return null;
	}
	if (buffer.length() > 0) {
	HTMLPrinter.insertPageProlog(buffer, 0, fgStyleSheet);
	HTMLPrinter.addPageEpilog(buffer);
	return buffer.toString();
	}
	return null;
	}

	/**
	* Returns the Javadoc in HTML format.
	*
	* @param result
	* the Script elements for which to get the Javadoc
	* @return a string with the Javadoc in HTML format.
	*/
	private String getScriptdocHtmlDetailed(Object[] result) {
	final StringBuffer buffer = new StringBuffer();
	final List<String> nodocs = new ArrayList<String>();
	for (int i = 0; i < result.length; i++) {
	final Object member = result[i];
	Reader reader = ScriptDocumentationAccess
	.getHTMLContentReader(getNature(), member, true, true);
	if (reader != null) {
	buffer.append("<b>"); //$NON-NLS-1$
	buffer.append(getInfoText(member));
	buffer.append("</b>"); //$NON-NLS-1$
	HTMLPrinter.addParagraph(buffer, reader);
	} else {
	if (member instanceof IModelElement) {
	nodocs.add(ScriptElementLabels.getDefault().getElementLabel(
	(IModelElement) member,
	LABEL_FLAGS \| ScriptElementLabels.APPEND_FILE));
	} else {
	// TODO
	}
	}
	}
	if (!nodocs.isEmpty()) {
	Collections.sort(nodocs);
	HTMLPrinter.addParagraph(buffer,
	InfoViewMessages.ScriptdocView_noAttachedInformationHeader);
	HTMLPrinter.startBulletList(buffer);
	for (String s : nodocs) {
	HTMLPrinter.addBullet(buffer, s);
	}
	HTMLPrinter.endBulletList(buffer);
	}
	return addPrologeEpilog(buffer);
	}

	/**
	* Returns the Javadoc in HTML format.
	*
	* @param result
	* the Script elements for which to get the Javadoc
	* @return a string with the Javadoc in HTML format.
	*/
	private String getScriptdocHtmlList(IModelElement[] result) {
	final StringBuffer buffer = new StringBuffer();
	HTMLPrinter.startBulletList(buffer);
	for (int i = 0; i < result.length; i++) {
	final IModelElement curr = result[i];
	if (curr instanceof IMember) {
	final IMember member = (IMember) curr;
	HTMLPrinter.addBullet(buffer, getInfoText(member));
	}
	}
	HTMLPrinter.endBulletList(buffer);
	return addPrologeEpilog(buffer);
	}

	/**
	* Returns the Javadoc in HTML format.
	*
	* @param result
	* the Script elements for which to get the Javadoc
	* @return a string with the Javadoc in HTML format.
	*/
	private String getScriptdocHtml(IModelElement curr) {
	StringBuffer buffer = new StringBuffer();
	if (curr instanceof IMember) {
	IMember member = (IMember) curr;
	// HTMLPrinter.addSmallHeader(buffer, getInfoText(member));
	Reader reader = ScriptDocumentationAccess
	.getHTMLContentReader(getNature(), member, true, true);
	if (reader != null) {
	HTMLPrinter.addParagraph(buffer, reader);
	} else {
	// Provide hint why there's no Javadoc
	HTMLPrinter.addParagraph(buffer,
	InfoViewMessages.ScriptdocView_noAttachedInformation);
	}
	}
	return addPrologeEpilog(buffer);
	}

	private String addPrologeEpilog(StringBuffer buffer) {
	if (buffer.length() > 0) {
	HTMLPrinter.insertPageProlog(buffer, 0, fBackgroundColorRGB,
	fForegroundColorRGB, fgStyleSheet);
	HTMLPrinter.addPageEpilog(buffer);
	return buffer.toString();
	}
	return null;
	}

	/**
	* The method is overridden to compare {@link ScriptEditor} nature with the
	* nature of this view.
	*
	* @see org.eclipse.dltk.ui.infoviews.AbstractInfoView#isValidWorkbenchPart(org.eclipse.ui.IWorkbenchPart)
	*/
	@Override
	protected boolean isValidWorkbenchPart(IWorkbenchPart part) {
	if (part instanceof IEditorPart) {
	final IEditorPart editor = (IEditorPart) part;
	final String editorNature = ScriptUtils.getNatureId(editor);
	if (editorNature != null) {
	return editorNature.equals(getNature());
	}
	ISourceModule sourceModule = EditorUtility
	.getEditorInputModelElement(editor, false);
	if (sourceModule != null) {
	final IDLTKLanguageToolkit toolkit = DLTKLanguageManager
	.getLanguageToolkit(sourceModule);
	return toolkit != null
	&& toolkit.getNatureId().equals(getNature());
	}
	}
	return false;
	}

	/**
	* Gets the label for the given member.
	*
	* @param member
	* the Script member
	* @return a string containing the member's label
	*/
	private String getInfoText(Object member) {
	if (member instanceof IModelElement) {
	return ScriptElementLabels.getDefault()
	.getElementLabel((IModelElement) member, LABEL_FLAGS);
	} else {
	// TODO
	return null;
	}
	}

	@Override
	protected Control getControl() {
	if (fIsUsingBrowserWidget)
	return fBrowser;
	else
	return fText;
	}

	@Override
	protected String getHelpContextId() {
	// return IJavaHelpContextIds.JAVADOC_VIEW;
	// TODO: add help support here
	return ""; //$NON-NLS-1$
	}
	}