/*******************************************************************************
 * Copyright (c) 2006, 2016 IBM Corporation 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:
 *     IBM Corporation - initial API and implementation
 *     QNX Software Systems - Mikhail Khodjaiants - Registers View (Bug 53640)
 *     Wind River Systems - adapted to work with platform Modules view (bug 210558)
 *******************************************************************************/
package org.eclipse.cdt.debug.internal.ui.views.modules;

import org.eclipse.cdt.core.IAddress;
import org.eclipse.cdt.core.model.ICElement;
import org.eclipse.cdt.debug.core.model.ICModule;
import org.eclipse.cdt.debug.internal.ui.ICDebugHelpContextIds;
import org.eclipse.cdt.debug.internal.ui.IInternalCDebugUIConstants;
import org.eclipse.cdt.debug.ui.CDebugUIPlugin;
import org.eclipse.cdt.debug.ui.ICDebugUIConstants;
import org.eclipse.core.runtime.IAdaptable;
import org.eclipse.core.runtime.IProgressMonitor;
import org.eclipse.core.runtime.IStatus;
import org.eclipse.core.runtime.Status;
import org.eclipse.core.runtime.jobs.Job;
import org.eclipse.debug.core.model.IDebugElement;
import org.eclipse.debug.internal.ui.views.variables.details.AbstractDetailPane;
import org.eclipse.debug.ui.IDebugView;
import org.eclipse.jface.action.IMenuListener;
import org.eclipse.jface.action.IMenuManager;
import org.eclipse.jface.action.MenuManager;
import org.eclipse.jface.action.Separator;
import org.eclipse.jface.resource.JFaceResources;
import org.eclipse.jface.text.Document;
import org.eclipse.jface.text.DocumentEvent;
import org.eclipse.jface.text.IDocument;
import org.eclipse.jface.text.IDocumentListener;
import org.eclipse.jface.text.IFindReplaceTarget;
import org.eclipse.jface.text.ITextOperationTarget;
import org.eclipse.jface.text.ITextViewer;
import org.eclipse.jface.text.source.SourceViewer;
import org.eclipse.jface.util.IPropertyChangeListener;
import org.eclipse.jface.util.PropertyChangeEvent;
import org.eclipse.jface.viewers.ISelectionChangedListener;
import org.eclipse.jface.viewers.IStructuredSelection;
import org.eclipse.jface.viewers.SelectionChangedEvent;
import org.eclipse.swt.SWT;
import org.eclipse.swt.custom.StyledText;
import org.eclipse.swt.events.FocusAdapter;
import org.eclipse.swt.events.FocusEvent;
import org.eclipse.swt.graphics.Point;
import org.eclipse.swt.layout.GridData;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Control;
import org.eclipse.swt.widgets.Menu;
import org.eclipse.ui.IWorkbenchActionConstants;
import org.eclipse.ui.PlatformUI;
import org.eclipse.ui.actions.ActionFactory;
import org.eclipse.ui.console.actions.TextViewerAction;
import org.eclipse.ui.progress.WorkbenchJob;
import org.eclipse.ui.texteditor.IWorkbenchActionDefinitionIds;

/**
 *
 */
public class ModuleDetailPane extends AbstractDetailPane implements IAdaptable, IPropertyChangeListener {

	/**
	 * These are the IDs for the actions in the context menu
	 */
	protected static final String DETAIL_COPY_ACTION = ActionFactory.COPY.getId() + ".SourceDetailPane"; //$NON-NLS-1$
	protected static final String DETAIL_SELECT_ALL_ACTION = IDebugView.SELECT_ALL_ACTION + ".SourceDetailPane"; //$NON-NLS-1$

	/**
	 * The ID, name and description of this pane are stored in constants so that the class
	 * does not have to be instantiated to access them.
	 */
	public static final String ID = "ModuleDetailPane"; //$NON-NLS-1$
	public static final String NAME = "Module Viewer";
	public static final String DESCRIPTION = "A detail pane that is based on a source viewer.  Displays as text and has actions for assigning values, content assist and text modifications.";

	/**
	 * Job to compute the details for a selection
	 */
	class DetailJob extends Job {

		private Object fElement;
		// whether a result was collected
		private IProgressMonitor fMonitor;

		public DetailJob(Object element) {
			super("compute module details"); //$NON-NLS-1$
			setSystem(true);
			fElement = element;
		}

		/* (non-Javadoc)
		 * @see org.eclipse.core.runtime.jobs.Job#run(org.eclipse.core.runtime.IProgressMonitor)
		 */
		@Override
		protected IStatus run(IProgressMonitor monitor) {
			fMonitor = monitor;

			String detail = ""; //$NON-NLS-1$
			if (fElement instanceof ICModule) {
				detail = getModuleDetail(((ICModule) fElement));
			}
			if (fElement instanceof ICElement) {
				detail = fElement.toString();
			}

			detailComputed(detail);
			return Status.OK_STATUS;
		}

		private void detailComputed(final String result) {
			if (!fMonitor.isCanceled()) {
				WorkbenchJob setDetail = new WorkbenchJob("set details") { //$NON-NLS-1$
					@Override
					public IStatus runInUIThread(IProgressMonitor monitor) {
						if (!fMonitor.isCanceled()) {
							getDetailDocument().set(result);
						}
						return Status.OK_STATUS;
					}
				};
				setDetail.setSystem(true);
				setDetail.schedule();
			}
		}

	}

	private String getModuleDetail(ICModule module) {
		StringBuilder sb = new StringBuilder();

		// Type
		String type = null;
		switch (module.getType()) {
		case ICModule.EXECUTABLE:
			type = ModulesMessages.getString("ModulesView.1"); //$NON-NLS-1$
			break;
		case ICModule.SHARED_LIBRARY:
			type = ModulesMessages.getString("ModulesView.2"); //$NON-NLS-1$
			break;
		}
		if (type != null) {
			sb.append(ModulesMessages.getString("ModulesView.3")); //$NON-NLS-1$
			sb.append(type);
			sb.append('\n');
		}

		// Symbols flag
		sb.append(ModulesMessages.getString("ModulesView.4")); //$NON-NLS-1$
		sb.append((module.areSymbolsLoaded()) ? ModulesMessages.getString("ModulesView.5") //$NON-NLS-1$
				: ModulesMessages.getString("ModulesView.6")); //$NON-NLS-1$
		sb.append('\n');

		// Symbols file
		sb.append(ModulesMessages.getString("ModulesView.7")); //$NON-NLS-1$
		sb.append(module.getSymbolsFileName().toOSString());
		sb.append('\n');

		// CPU
		String cpu = module.getCPU();
		if (cpu != null) {
			sb.append(ModulesMessages.getString("ModulesView.8")); //$NON-NLS-1$
			sb.append(cpu);
			sb.append('\n');
		}

		// Base address
		IAddress baseAddress = module.getBaseAddress();
		if (!baseAddress.isZero()) {
			sb.append(ModulesMessages.getString("ModulesView.9")); //$NON-NLS-1$
			sb.append(baseAddress.toHexAddressString());
			sb.append('\n');
		}

		// Size
		long size = module.getSize();
		if (size > 0) {
			sb.append(ModulesMessages.getString("ModulesView.10")); //$NON-NLS-1$
			sb.append(size);
			sb.append('\n');
		}

		return sb.toString();
	}

	/**
	 * The source viewer in which the computed string detail
	 * of selected modules will be displayed.
	 */
	private SourceViewer fSourceViewer;

	/**
	 * Variables used to create the detailed information for a selection
	 */
	private IDocument fDetailDocument;
	private DetailJob fDetailJob = null;

	/* (non-Javadoc)
	 * @see org.eclipse.debug.ui.IDetailPane#createControl(org.eclipse.swt.widgets.Composite)
	 */
	@Override
	public Control createControl(Composite parent) {

		createSourceViewer(parent);

		if (isInView()) {
			createViewSpecificComponents();
			createActions();
			CDebugUIPlugin.getDefault().getPreferenceStore().addPropertyChangeListener(this);
			JFaceResources.getFontRegistry().addListener(this);
		}

		return fSourceViewer.getControl();
	}

	/**
	 * Creates the source viewer in the given parent composite
	 *
	 * @param parent Parent composite to create the source viewer in
	 */
	private void createSourceViewer(Composite parent) {

		// Create & configure a SourceViewer
		fSourceViewer = new SourceViewer(parent, null, SWT.V_SCROLL | SWT.H_SCROLL);
		fSourceViewer.setDocument(getDetailDocument());
		fSourceViewer.getTextWidget().setFont(JFaceResources.getFont(IInternalCDebugUIConstants.DETAIL_PANE_FONT));
		fSourceViewer.setEditable(false);
		PlatformUI.getWorkbench().getHelpSystem().setHelp(fSourceViewer.getTextWidget(),
				ICDebugHelpContextIds.MODULES_DETAIL_PANE);
		Control control = fSourceViewer.getControl();
		GridData gd = new GridData(GridData.FILL_BOTH);
		control.setLayoutData(gd);
	}

	/**
	 * Creates listeners and other components that should only be added to the
	 * source viewer when this detail pane is inside a view.
	 */
	private void createViewSpecificComponents() {

		// Add a document listener so actions get updated when the document changes
		getDetailDocument().addDocumentListener(new IDocumentListener() {
			@Override
			public void documentAboutToBeChanged(DocumentEvent event) {
			}

			@Override
			public void documentChanged(DocumentEvent event) {
				updateSelectionDependentActions();
			}
		});

		// Add the selection listener so selection dependent actions get updated.
		fSourceViewer.getSelectionProvider().addSelectionChangedListener(new ISelectionChangedListener() {
			@Override
			public void selectionChanged(SelectionChangedEvent event) {
				updateSelectionDependentActions();
			}
		});

		// Add a focus listener to update actions when details area gains focus
		fSourceViewer.getControl().addFocusListener(new FocusAdapter() {
			@Override
			public void focusGained(FocusEvent e) {

				getViewSite().setSelectionProvider(fSourceViewer.getSelectionProvider());

				setGlobalAction(IDebugView.SELECT_ALL_ACTION, getAction(DETAIL_SELECT_ALL_ACTION));
				setGlobalAction(IDebugView.COPY_ACTION, getAction(DETAIL_COPY_ACTION));

				getViewSite().getActionBars().updateActionBars();
			}

			@Override
			public void focusLost(FocusEvent e) {

				getViewSite().setSelectionProvider(null);

				setGlobalAction(IDebugView.SELECT_ALL_ACTION, null);
				setGlobalAction(IDebugView.CUT_ACTION, null);
				setGlobalAction(IDebugView.COPY_ACTION, null);
				setGlobalAction(IDebugView.PASTE_ACTION, null);
				setGlobalAction(IDebugView.FIND_ACTION, null);

				getViewSite().getActionBars().updateActionBars();

			}
		});

		// Add a context menu to the detail area
		createDetailContextMenu(fSourceViewer.getTextWidget());
	}

	/**
	 * Creates the actions to add to the context menu
	 */
	private void createActions() {

		TextViewerAction textAction = new TextViewerAction(fSourceViewer, ITextOperationTarget.SELECT_ALL);
		textAction.configureAction("Select &All", "", ""); //$NON-NLS-2$ //$NON-NLS-3$
		textAction.setActionDefinitionId(IWorkbenchActionDefinitionIds.SELECT_ALL);
		PlatformUI.getWorkbench().getHelpSystem().setHelp(textAction,
				ICDebugHelpContextIds.MODULE_DETAIL_PANE_SELECT_ALL_ACTION);
		setAction(DETAIL_SELECT_ALL_ACTION, textAction);

		textAction = new TextViewerAction(fSourceViewer, ITextOperationTarget.COPY);
		textAction.configureAction("&Copy", "", ""); //$NON-NLS-2$ //$NON-NLS-3$
		textAction.setActionDefinitionId(IWorkbenchActionDefinitionIds.COPY);
		PlatformUI.getWorkbench().getHelpSystem().setHelp(textAction,
				ICDebugHelpContextIds.MODULE_DETAIL_PANE_COPY_ACTION);
		setAction(DETAIL_COPY_ACTION, textAction);

		setSelectionDependantAction(DETAIL_COPY_ACTION);

		updateSelectionDependentActions();
	}

	/**
	 * Create the context menu particular to the detail pane.  Note that anyone
	 * wishing to contribute an action to this menu must use
	 * <code>ICDebugUIConstants.MODULES_VIEW_DETAIL_ID</code> as the
	 * <code>targetID</code> in the extension XML.
	 */
	protected void createDetailContextMenu(Control menuControl) {
		MenuManager menuMgr = new MenuManager();
		menuMgr.setRemoveAllWhenShown(true);
		menuMgr.addMenuListener(new IMenuListener() {
			@Override
			public void menuAboutToShow(IMenuManager mgr) {
				fillDetailContextMenu(mgr);
			}
		});
		Menu menu = menuMgr.createContextMenu(menuControl);
		menuControl.setMenu(menu);

		getViewSite().registerContextMenu(ICDebugUIConstants.MODULES_VIEW_DETAIL_ID, menuMgr,
				fSourceViewer.getSelectionProvider());

	}

	/**
	* Adds items to the detail pane's context menu including any extension defined
	* actions.
	*
	* @param menu The menu to add the item to.
	*/
	protected void fillDetailContextMenu(IMenuManager menu) {

		menu.add(new Separator(ICDebugUIConstants.MODULES_GROUP));
		menu.add(new Separator());
		menu.add(getAction(DETAIL_COPY_ACTION));
		menu.add(getAction(DETAIL_SELECT_ALL_ACTION));
		menu.add(new Separator());
		menu.add(new Separator(IWorkbenchActionConstants.MB_ADDITIONS));

	}

	/* (non-Javadoc)
	 * @see org.eclipse.debug.ui.IDetailPane#display(org.eclipse.jface.viewers.IStructuredSelection)
	 */
	@Override
	public void display(IStructuredSelection selection) {

		if (selection == null) {
			clearSourceViewer();
			return;
		}

		if (isInView()) {
			fSourceViewer.setEditable(true);
		}

		if (selection.isEmpty()) {
			clearSourceViewer();
			return;
		}

		Object firstElement = selection.getFirstElement();
		if (firstElement != null && firstElement instanceof IDebugElement) {
			String modelID = ((IDebugElement) firstElement).getModelIdentifier();
		}

		synchronized (this) {
			if (fDetailJob != null) {
				fDetailJob.cancel();
			}
			fDetailJob = new DetailJob(selection.getFirstElement());
			fDetailJob.schedule();
		}

	}

	/* (non-Javadoc)
	 * @see org.eclipse.debug.ui.IDetailPane#setFocus()
	 */
	@Override
	public boolean setFocus() {
		if (fSourceViewer != null) {
			fSourceViewer.getTextWidget().setFocus();
			return true;
		}
		return false;
	}

	/* (non-Javadoc)
	 * @see org.eclipse.debug.internal.ui.views.variables.details.AbstractDetailPane#dispose()
	 */
	@Override
	public void dispose() {
		super.dispose();

		if (fDetailJob != null)
			fDetailJob.cancel();
		if (fSourceViewer != null && fSourceViewer.getControl() != null)
			fSourceViewer.getControl().dispose();

		if (isInView()) {
			CDebugUIPlugin.getDefault().getPreferenceStore().removePropertyChangeListener(this);
			JFaceResources.getFontRegistry().removeListener(this);
		}
	}

	/* (non-Javadoc)
	 * @see org.eclipse.debug.ui.IDetailPane#getDescription()
	 */
	@Override
	public String getDescription() {
		return DESCRIPTION;
	}

	/* (non-Javadoc)
	 * @see org.eclipse.debug.ui.IDetailPane#getID()
	 */
	@Override
	public String getID() {
		return ID;
	}

	/* (non-Javadoc)
	 * @see org.eclipse.debug.ui.IDetailPane#getName()
	 */
	@Override
	public String getName() {
		return NAME;
	}

	@SuppressWarnings("unchecked")
	@Override
	public <T> T getAdapter(Class<T> required) {
		if (ITextViewer.class.equals(required)) {
			return (T) fSourceViewer;
		}
		return null;
	}

	/**
	 * Lazily instantiate and return a Document for the detail pane text viewer.
	 */
	protected IDocument getDetailDocument() {
		if (fDetailDocument == null) {
			fDetailDocument = new Document();
		}
		return fDetailDocument;
	}

	/**
	 * Clears the source viewer, removes all text.
	 */
	protected void clearSourceViewer() {
		if (fDetailJob != null) {
			fDetailJob.cancel();
		}
		fDetailDocument.set(""); //$NON-NLS-1$
		fSourceViewer.setEditable(false);
	}

	/* (non-Javadoc)
	 * @see org.eclipse.jface.util.IPropertyChangeListener#propertyChange(org.eclipse.jface.util.PropertyChangeEvent)
	 */
	@Override
	public void propertyChange(PropertyChangeEvent event) {
		String propertyName = event.getProperty();
		if (propertyName.equals(IInternalCDebugUIConstants.DETAIL_PANE_FONT)) {
			fSourceViewer.getTextWidget().setFont(JFaceResources.getFont(IInternalCDebugUIConstants.DETAIL_PANE_FONT));
		}

	}

	/**
	 * Wrapper class that wraps around an IFindReplaceTarget.  Allows the detail pane to scroll
	 * to text selected by the find/replace action.  The source viewer treats the text as a single
	 * line, even when the text is wrapped onto several lines so the viewer will not scroll properly
	 * on it's own.  See bug 178106.
	 */
	class FindReplaceTargetWrapper implements IFindReplaceTarget {

		private IFindReplaceTarget fTarget;

		/**
		 * Constructor
		 *
		 * @param target find/replace target this class will wrap around.
		 */
		public FindReplaceTargetWrapper(IFindReplaceTarget target) {
			fTarget = target;
		}

		/* (non-Javadoc)
		 * @see org.eclipse.jface.text.IFindReplaceTarget#canPerformFind()
		 */
		@Override
		public boolean canPerformFind() {
			return fTarget.canPerformFind();
		}

		/* (non-Javadoc)
		 * @see org.eclipse.jface.text.IFindReplaceTarget#findAndSelect(int, java.lang.String, boolean, boolean, boolean)
		 */
		@Override
		public int findAndSelect(int widgetOffset, String findString, boolean searchForward, boolean caseSensitive,
				boolean wholeWord) {
			int position = fTarget.findAndSelect(widgetOffset, findString, searchForward, caseSensitive, wholeWord);
			// Explicitly tell the widget to show the selection because the viewer thinks the text is all on one line, even if wrapping is turned on.
			if (fSourceViewer != null) {
				StyledText text = fSourceViewer.getTextWidget();
				if (text != null && !text.isDisposed()) {
					text.showSelection();
				}
			}
			return position;
		}

		/* (non-Javadoc)
		 * @see org.eclipse.jface.text.IFindReplaceTarget#getSelection()
		 */
		@Override
		public Point getSelection() {
			return fTarget.getSelection();
		}

		/* (non-Javadoc)
		 * @see org.eclipse.jface.text.IFindReplaceTarget#getSelectionText()
		 */
		@Override
		public String getSelectionText() {
			return fTarget.getSelectionText();
		}

		/* (non-Javadoc)
		 * @see org.eclipse.jface.text.IFindReplaceTarget#isEditable()
		 */
		@Override
		public boolean isEditable() {
			return fTarget.isEditable();
		}

		/* (non-Javadoc)
		 * @see org.eclipse.jface.text.IFindReplaceTarget#replaceSelection(java.lang.String)
		 */
		@Override
		public void replaceSelection(String text) {
			fTarget.replaceSelection(text);
		}
	}

}
