/*******************************************************************************
 * Copyright (c) 2000, 2019 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
 *     Jesper Steen Moller - Enhancement 254677 - filter getters/setters
 *******************************************************************************/
package org.eclipse.jdt.internal.debug.ui;

import java.util.ArrayList;

import org.eclipse.debug.internal.ui.SWTFactory;
import org.eclipse.debug.ui.DebugUITools;
import org.eclipse.jdt.core.IJavaElement;
import org.eclipse.jdt.core.IType;
import org.eclipse.jdt.core.JavaModelException;
import org.eclipse.jdt.core.search.SearchEngine;
import org.eclipse.jdt.ui.IJavaElementSearchConstants;
import org.eclipse.jdt.ui.JavaUI;
import org.eclipse.jface.dialogs.IDialogConstants;
import org.eclipse.jface.preference.IPreferenceStore;
import org.eclipse.jface.preference.PreferencePage;
import org.eclipse.jface.viewers.CheckStateChangedEvent;
import org.eclipse.jface.viewers.CheckboxTableViewer;
import org.eclipse.jface.viewers.ICheckStateListener;
import org.eclipse.jface.viewers.ISelection;
import org.eclipse.jface.viewers.ISelectionChangedListener;
import org.eclipse.jface.viewers.IStructuredContentProvider;
import org.eclipse.jface.viewers.IStructuredSelection;
import org.eclipse.jface.viewers.SelectionChangedEvent;
import org.eclipse.jface.viewers.Viewer;
import org.eclipse.swt.SWT;
import org.eclipse.swt.events.KeyAdapter;
import org.eclipse.swt.events.KeyEvent;
import org.eclipse.swt.events.SelectionEvent;
import org.eclipse.swt.events.SelectionListener;
import org.eclipse.swt.layout.GridData;
import org.eclipse.swt.layout.GridLayout;
import org.eclipse.swt.widgets.Button;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Control;
import org.eclipse.swt.widgets.Event;
import org.eclipse.swt.widgets.Label;
import org.eclipse.swt.widgets.Listener;
import org.eclipse.swt.widgets.TableItem;
import org.eclipse.ui.IWorkbench;
import org.eclipse.ui.IWorkbenchPreferencePage;
import org.eclipse.ui.PlatformUI;
import org.eclipse.ui.dialogs.ElementListSelectionDialog;
import org.eclipse.ui.dialogs.SelectionDialog;

/**
 * The preference page for Java step filtering, located at the node Java > Debug > Step Filtering
 *
 * @since 3.0
 */
public class JavaStepFilterPreferencePage extends PreferencePage implements IWorkbenchPreferencePage {

	public static final String PAGE_ID = "org.eclipse.jdt.debug.ui.JavaStepFilterPreferencePage"; //$NON-NLS-1$

	/**
	 * Content provider for the table.  Content consists of instances of StepFilter.
	 * @since 3.2
	 */
	class StepFilterContentProvider implements IStructuredContentProvider {
		public StepFilterContentProvider() {
			initTableState(false);
		}

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

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

		@Override
		public void dispose() {}
	}

	//widgets
	private CheckboxTableViewer fTableViewer;
	private Button fUseStepFiltersButton;
	private Button fAddPackageButton;
	private Button fAddTypeButton;
	private Button fRemoveFilterButton;
	private Button fAddFilterButton;
	private Button fFilterSyntheticButton;
	private Button fFilterStaticButton;
	private Button fFilterGetterButton;
	private Button fFilterSetterButton;
	private Button fFilterConstructorButton;
	private Button fStepThruButton;
	private Button fSelectAllButton;
	private Button fDeselectAllButton;

	/**
	 * Constructor
	 */
	public JavaStepFilterPreferencePage() {
		super();
		setPreferenceStore(JDIDebugUIPlugin.getDefault().getPreferenceStore());
		setTitle(DebugUIMessages.JavaStepFilterPreferencePage_title);
		setDescription(DebugUIMessages.JavaStepFilterPreferencePage_description);
	}

	/* (non-Javadoc)
	 * @see org.eclipse.jface.preference.PreferencePage#createContents(org.eclipse.swt.widgets.Composite)
	 */
	@Override
	protected Control createContents(Composite parent) {
		PlatformUI.getWorkbench().getHelpSystem().setHelp(getControl(), IJavaDebugHelpContextIds.JAVA_STEP_FILTER_PREFERENCE_PAGE);
	//The main composite
		Composite composite = SWTFactory.createComposite(parent, parent.getFont(), 1, 1, GridData.FILL_BOTH, 0, 0);
		createStepFilterPreferences(composite);
		return composite;
	}

	/* (non-Javadoc)
	 * @see org.eclipse.ui.IWorkbenchPreferencePage#init(org.eclipse.ui.IWorkbench)
	 */
	@Override
	public void init(IWorkbench workbench) {}

	/**
	 * handles the filter button being clicked
	 * @param event the clicked event
	 */
	private void handleFilterViewerKeyPress(KeyEvent event) {
		if (event.character == SWT.DEL && event.stateMask == 0) {
			removeFilters();
		}
	}

	/**
	 * Create a group to contain the step filter related widgetry
	 */
	private void createStepFilterPreferences(Composite parent) {
		Composite container = SWTFactory.createComposite(parent, parent.getFont(), 2, 1, GridData.FILL_BOTH, 0, 0);
		fUseStepFiltersButton = SWTFactory.createCheckButton(container,	DebugUIMessages.JavaStepFilterPreferencePage__Use_step_filters,	null, DebugUITools.isUseStepFilters(), 2);
		fUseStepFiltersButton.addSelectionListener(new SelectionListener() {
				@Override
				public void widgetSelected(SelectionEvent e) {
					setPageEnablement(fUseStepFiltersButton.getSelection());
				}
				@Override
				public void widgetDefaultSelected(SelectionEvent e) {}
			}
		);
		SWTFactory.createLabel(container, DebugUIMessages.JavaStepFilterPreferencePage_Defined_step_fi_lters__8, 2);
		fTableViewer = CheckboxTableViewer.newCheckList(container, SWT.H_SCROLL | SWT.V_SCROLL | SWT.BORDER | SWT.MULTI | SWT.FULL_SELECTION);
		fTableViewer.getTable().setFont(container.getFont());
		fTableViewer.setLabelProvider(new FilterLabelProvider());
		fTableViewer.setComparator(new FilterViewerComparator());
		fTableViewer.setContentProvider(new StepFilterContentProvider());
		fTableViewer.setInput(getAllStoredFilters(false));
		fTableViewer.getTable().setLayoutData(new GridData(GridData.FILL_BOTH));
		fTableViewer.addCheckStateListener(new ICheckStateListener() {
			@Override
			public void checkStateChanged(CheckStateChangedEvent event) {
				((Filter)event.getElement()).setChecked(event.getChecked());
			}
		});
		fTableViewer.addSelectionChangedListener(new ISelectionChangedListener() {
			@Override
			public void selectionChanged(SelectionChangedEvent event) {
				ISelection selection = event.getSelection();
				if (selection.isEmpty()) {
					fRemoveFilterButton.setEnabled(false);
				} else {
					fRemoveFilterButton.setEnabled(true);
				}
			}
		});
		fTableViewer.getControl().addKeyListener(new KeyAdapter() {
			@Override
			public void keyPressed(KeyEvent event) {
				handleFilterViewerKeyPress(event);
			}
		});

		createStepFilterButtons(container);
		createStepFilterCheckboxes(container);

		setPageEnablement(fUseStepFiltersButton.getSelection());
	}

	/**
	 * initializes the checked state of the filters when the dialog opens
	 * @since 3.2
	 */
	private void initTableState(boolean defaults) {
		Filter[] filters = getAllStoredFilters(defaults);
		for(int i = 0; i < filters.length; i++) {
			fTableViewer.add(filters[i]);
			fTableViewer.setChecked(filters[i], filters[i].isChecked());
		}
	}

	/**
	 * Enables or disables the widgets on the page, with the
	 * exception of <code>fUseStepFiltersButton</code> according
	 * to the passed boolean
	 * @param enabled the new enablement status of the page's widgets
	 * @since 3.2
	 */
	protected void setPageEnablement(boolean enabled) {
		fAddFilterButton.setEnabled(enabled);
		fAddPackageButton.setEnabled(enabled);
		fAddTypeButton.setEnabled(enabled);
		fDeselectAllButton.setEnabled(enabled);
		fSelectAllButton.setEnabled(enabled);
		fFilterConstructorButton.setEnabled(enabled);
		fStepThruButton.setEnabled(enabled);
		fFilterGetterButton.setEnabled(enabled);
		fFilterSetterButton.setEnabled(enabled);
		fFilterStaticButton.setEnabled(enabled);
		fFilterSyntheticButton.setEnabled(enabled);
		fTableViewer.getTable().setEnabled(enabled);
		fRemoveFilterButton.setEnabled(enabled & !fTableViewer.getSelection().isEmpty());
	}

	/**
	 * create the checked preferences for the page
	 * @param container the parent container
	 */
	private void createStepFilterCheckboxes(Composite container) {
		fFilterSyntheticButton = SWTFactory.createCheckButton(container,
				DebugUIMessages.JavaStepFilterPreferencePage_Filter_s_ynthetic_methods__requires_VM_support__17,
				null, getPreferenceStore().getBoolean(IJDIPreferencesConstants.PREF_FILTER_SYNTHETICS), 2);
		fFilterStaticButton = SWTFactory.createCheckButton(container,
				DebugUIMessages.JavaStepFilterPreferencePage_Filter_static__initializers_18,
				null, getPreferenceStore().getBoolean(IJDIPreferencesConstants.PREF_FILTER_STATIC_INITIALIZERS), 2);
		fFilterConstructorButton = SWTFactory.createCheckButton(container,
				DebugUIMessages.JavaStepFilterPreferencePage_Filter_co_nstructors_19,
				null, getPreferenceStore().getBoolean(IJDIPreferencesConstants.PREF_FILTER_CONSTRUCTORS), 2);
		fFilterGetterButton = SWTFactory.createCheckButton(container,
				DebugUIMessages.JavaStepFilterPreferencePage_Filter_getters,
				null, getPreferenceStore().getBoolean(IJDIPreferencesConstants.PREF_FILTER_GETTERS), 2);
		fFilterSetterButton = SWTFactory.createCheckButton(container,
				DebugUIMessages.JavaStepFilterPreferencePage_Filter_setters,
				null, getPreferenceStore().getBoolean(IJDIPreferencesConstants.PREF_FILTER_SETTERS), 2);
		fStepThruButton = SWTFactory.createCheckButton(container,
				DebugUIMessages.JavaStepFilterPreferencePage_0,
				null, getPreferenceStore().getBoolean(IJDIPreferencesConstants.PREF_STEP_THRU_FILTERS), 2);
	}

	/**
	 * Creates the button for the step filter options
	 * @param container the parent container
	 */
	private void createStepFilterButtons(Composite container) {
		initializeDialogUnits(container);
		// button container
		Composite buttonContainer = new Composite(container, SWT.NONE);
		GridData gd = new GridData(GridData.FILL_VERTICAL);
		buttonContainer.setLayoutData(gd);
		GridLayout buttonLayout = new GridLayout();
		buttonLayout.numColumns = 1;
		buttonLayout.marginHeight = 0;
		buttonLayout.marginWidth = 0;
		buttonContainer.setLayout(buttonLayout);
	//Add filter button
		fAddFilterButton = SWTFactory.createPushButton(buttonContainer,
				DebugUIMessages.JavaStepFilterPreferencePage_Add__Filter_9,
				DebugUIMessages.JavaStepFilterPreferencePage_Key_in_the_name_of_a_new_step_filter_10, null);
		fAddFilterButton.addListener(SWT.Selection, new Listener() {
			@Override
			public void handleEvent(Event e) {
				addFilter();
			}
		});
	//Add type button
		fAddTypeButton = SWTFactory.createPushButton(buttonContainer,
				DebugUIMessages.JavaStepFilterPreferencePage_Add__Type____11,
				DebugUIMessages.JavaStepFilterPreferencePage_Choose_a_Java_type_and_add_it_to_step_filters_12, null);
		fAddTypeButton.addListener(SWT.Selection, new Listener() {
			@Override
			public void handleEvent(Event e) {
				addType();
			}
		});
	//Add package button
		fAddPackageButton = SWTFactory.createPushButton(buttonContainer,
				DebugUIMessages.JavaStepFilterPreferencePage_Add__Package____13,
				DebugUIMessages.JavaStepFilterPreferencePage_Choose_a_package_and_add_it_to_step_filters_14, null);
		fAddPackageButton.addListener(SWT.Selection, new Listener() {
			@Override
			public void handleEvent(Event e) {
				addPackage();
			}
		});
	//Remove button
		fRemoveFilterButton = SWTFactory.createPushButton(buttonContainer,
				DebugUIMessages.JavaStepFilterPreferencePage__Remove_15,
				DebugUIMessages.JavaStepFilterPreferencePage_Remove_all_selected_step_filters_16,
				null);
		fRemoveFilterButton.addListener(SWT.Selection, new Listener() {
			@Override
			public void handleEvent(Event e) {
				removeFilters();
			}
		});
		fRemoveFilterButton.setEnabled(false);

		Label separator= new Label(buttonContainer, SWT.NONE);
		separator.setVisible(false);
		gd = new GridData();
		gd.horizontalAlignment= GridData.FILL;
		gd.verticalAlignment= GridData.BEGINNING;
		gd.heightHint= 4;
		separator.setLayoutData(gd);
	//Select All button
		fSelectAllButton = SWTFactory.createPushButton(buttonContainer,
				DebugUIMessages.JavaStepFilterPreferencePage__Select_All_1,
				DebugUIMessages.JavaStepFilterPreferencePage_Selects_all_step_filters_2, null);
		fSelectAllButton.addListener(SWT.Selection, new Listener() {
			@Override
			public void handleEvent(Event e) {
				fTableViewer.setAllChecked(true);
			}
		});
	//De-Select All button
		fDeselectAllButton = SWTFactory.createPushButton(buttonContainer,
				DebugUIMessages.JavaStepFilterPreferencePage_Deselect_All_3,
				DebugUIMessages.JavaStepFilterPreferencePage_Deselects_all_step_filters_4, null);
		fDeselectAllButton.addListener(SWT.Selection, new Listener() {
			@Override
			public void handleEvent(Event e) {
				fTableViewer.setAllChecked(false);
			}
		});

	}

	/**
	 * Allows a new filter to be added to the listing
	 */
	private void addFilter() {
		Filter newfilter = CreateStepFilterDialog.showCreateStepFilterDialog(getShell(), getAllFiltersFromTable());
		if (newfilter != null) {
			fTableViewer.add(newfilter);
			fTableViewer.setChecked(newfilter, true);
			fTableViewer.refresh(newfilter);
		}
	}

	/**
	 * add a new type to the listing of available filters
	 */
	private void addType() {
		try {
			SelectionDialog dialog = JavaUI.createTypeDialog(getShell(),
				PlatformUI.getWorkbench().getProgressService(),
				SearchEngine.createWorkspaceScope(),
				IJavaElementSearchConstants.CONSIDER_CLASSES,
				false);
			dialog.setTitle(DebugUIMessages.JavaStepFilterPreferencePage_Add_type_to_step_filters_20);
			dialog.setMessage(DebugUIMessages.JavaStepFilterPreferencePage_Select_a_type_to_filter_when_stepping_23);
			if (dialog.open() == IDialogConstants.OK_ID) {
				Object[] types = dialog.getResult();
				if (types != null && types.length > 0) {
					IType type = (IType)types[0];
					addFilter(type.getFullyQualifiedName(), true);
				}
			}
		}
		catch (JavaModelException jme) {
			ExceptionHandler.handle(jme,
					DebugUIMessages.JavaStepFilterPreferencePage_Add_type_to_step_filters_20,
					DebugUIMessages.JavaStepFilterPreferencePage_Could_not_open_type_selection_dialog_for_step_filters_21);
		}
	}

	/**
	 * add a new package to the list of all available package filters
	 */
	private void addPackage() {
		try {
			ElementListSelectionDialog dialog = JDIDebugUIPlugin.createAllPackagesDialog(getShell(), null, false);
			dialog.setTitle(DebugUIMessages.JavaStepFilterPreferencePage_Add_package_to_step_filters_24);
			dialog.setMessage(DebugUIMessages.JavaStepFilterPreferencePage_Select_a_package_to_filter_when_stepping_27);
			dialog.setMultipleSelection(true);
			if (dialog.open() == IDialogConstants.OK_ID) {
				Object[] packages = dialog.getResult();
				if (packages != null) {
					IJavaElement pkg = null;
					for (int i = 0; i < packages.length; i++) {
						pkg = (IJavaElement)packages[i];
						String filter = pkg.getElementName() + ".*"; //$NON-NLS-1$
						addFilter(filter, true);
					}
				}
			}

		}
		catch (JavaModelException jme) {
			ExceptionHandler.handle(jme,
					DebugUIMessages.JavaStepFilterPreferencePage_Add_package_to_step_filters_24,
					DebugUIMessages.JavaStepFilterPreferencePage_Could_not_open_package_selection_dialog_for_step_filters_25);
		}
	}

	/**
	 * Removes the currently selected filters.
	 */
	protected void removeFilters() {
		fTableViewer.remove(((IStructuredSelection)fTableViewer.getSelection()).toArray());
	}

	/* (non-Javadoc)
	 * @see org.eclipse.jface.preference.PreferencePage#performOk()
	 */
	@Override
	public boolean performOk() {
		DebugUITools.setUseStepFilters(fUseStepFiltersButton.getSelection());
		IPreferenceStore store = getPreferenceStore();
		ArrayList<String> active = new ArrayList<>();
		ArrayList<String> inactive = new ArrayList<>();
		String name = ""; //$NON-NLS-1$
		Filter[] filters = getAllFiltersFromTable();
		for(int i = 0; i < filters.length; i++) {
			name = filters[i].getName();
			if(filters[i].isChecked()) {
				active.add(name);
			}
			else {
				inactive.add(name);
			}
		}
		String pref = JavaDebugOptionsManager.serializeList(active.toArray(new String[active.size()]));
		store.setValue(IJDIPreferencesConstants.PREF_ACTIVE_FILTERS_LIST, pref);
		pref = JavaDebugOptionsManager.serializeList(inactive.toArray(new String[inactive.size()]));
		store.setValue(IJDIPreferencesConstants.PREF_INACTIVE_FILTERS_LIST, pref);
		store.setValue(IJDIPreferencesConstants.PREF_FILTER_CONSTRUCTORS, fFilterConstructorButton.getSelection());
		store.setValue(IJDIPreferencesConstants.PREF_FILTER_STATIC_INITIALIZERS, fFilterStaticButton.getSelection());
		store.setValue(IJDIPreferencesConstants.PREF_FILTER_GETTERS, fFilterGetterButton.getSelection());
		store.setValue(IJDIPreferencesConstants.PREF_FILTER_SETTERS, fFilterSetterButton.getSelection());
		store.setValue(IJDIPreferencesConstants.PREF_FILTER_SYNTHETICS, fFilterSyntheticButton.getSelection());
		store.setValue(IJDIPreferencesConstants.PREF_STEP_THRU_FILTERS, fStepThruButton.getSelection());
		return super.performOk();
	}

	/* (non-Javadoc)
	 * @see org.eclipse.jface.preference.PreferencePage#performDefaults()
	 */
	@Override
	protected void performDefaults() {
		// Cannot use DebugUITools.isUseStepFilters() as this not give the default value, no API from Platform to get the default value
		fUseStepFiltersButton.setSelection(false);
		setPageEnablement(false);
		fFilterSyntheticButton.setSelection(getPreferenceStore().getDefaultBoolean(IJDIPreferencesConstants.PREF_FILTER_SYNTHETICS));
		fFilterStaticButton.setSelection(getPreferenceStore().getDefaultBoolean(IJDIPreferencesConstants.PREF_FILTER_STATIC_INITIALIZERS));
		fFilterConstructorButton.setSelection(getPreferenceStore().getDefaultBoolean(IJDIPreferencesConstants.PREF_FILTER_CONSTRUCTORS));
		fFilterGetterButton.setSelection(getPreferenceStore().getDefaultBoolean(IJDIPreferencesConstants.PREF_FILTER_GETTERS));
		fFilterSetterButton.setSelection(getPreferenceStore().getDefaultBoolean(IJDIPreferencesConstants.PREF_FILTER_SETTERS));
		fStepThruButton.setSelection(getPreferenceStore().getDefaultBoolean(IJDIPreferencesConstants.PREF_STEP_THRU_FILTERS));

		fTableViewer.getTable().removeAll();
		initTableState(true);
		super.performDefaults();
	}

	/**
	 * adds a single filter to the viewer
	 * @param filter the new filter to add
	 * @param checked the checked state of the new filter
	 * @since 3.2
	 */
	protected void addFilter(String filter, boolean checked) {
		if(filter != null) {
			Filter f = new Filter(filter, checked);
			fTableViewer.add(f);
			fTableViewer.setChecked(f, checked);
		}
	}

	/**
	 * returns all of the filters from the table, this includes ones that have not yet been saved
	 * @return a possibly empty lits of filters fron the table
	 * @since 3.2
	 */
	protected Filter[] getAllFiltersFromTable() {
		TableItem[] items = fTableViewer.getTable().getItems();
		Filter[] filters = new Filter[items.length];
		for(int i = 0; i < items.length; i++) {
			filters[i] = (Filter)items[i].getData();
			filters[i].setChecked(items[i].getChecked());
		}
		return filters;
	}

	/**
	 * Returns all of the committed filters
	 * @return an array of committed filters
	 * @since 3.2
	 */
	protected Filter[] getAllStoredFilters(boolean defaults) {
		Filter[] filters = null;
		String[] activefilters, inactivefilters;
		IPreferenceStore store = getPreferenceStore();
		if(defaults) {
			activefilters = JavaDebugOptionsManager.parseList(store.getDefaultString(IJDIPreferencesConstants.PREF_ACTIVE_FILTERS_LIST));
			inactivefilters = JavaDebugOptionsManager.parseList(store.getDefaultString(IJDIPreferencesConstants.PREF_INACTIVE_FILTERS_LIST));
		}
		else {
			activefilters = JavaDebugOptionsManager.parseList(store.getString(IJDIPreferencesConstants.PREF_ACTIVE_FILTERS_LIST));
			inactivefilters = JavaDebugOptionsManager.parseList(store.getString(IJDIPreferencesConstants.PREF_INACTIVE_FILTERS_LIST));
		}
		filters = new Filter[activefilters.length + inactivefilters.length];
		for(int i = 0; i < activefilters.length; i++) {
			filters[i] = new Filter(activefilters[i], true);
		}
		for(int i = 0; i < inactivefilters.length; i++) {
			filters[i+activefilters.length] = new Filter(inactivefilters[i], false);
		}
		return filters;
	}
}