/*******************************************************************************

 * Copyright (c) 2000, 2007 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:

 *     IBM Corporation - initial API and implementation

 *******************************************************************************/

package com.nokia.carbide.search.system2.internal.ui;

import org.eclipse.core.runtime.IStatus;

import org.eclipse.core.runtime.Status;

import org.eclipse.swt.SWT;

import org.eclipse.swt.events.ModifyEvent;

import org.eclipse.swt.events.ModifyListener;

import org.eclipse.swt.events.SelectionAdapter;

import org.eclipse.swt.events.SelectionEvent;

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.Label;

import org.eclipse.swt.widgets.Shell;

import org.eclipse.swt.widgets.Table;

import org.eclipse.swt.widgets.Text;

import org.eclipse.jface.dialogs.IDialogSettings;

import org.eclipse.jface.dialogs.StatusDialog;

import org.eclipse.jface.viewers.ArrayContentProvider;

import org.eclipse.jface.viewers.CheckStateChangedEvent;

import org.eclipse.jface.viewers.CheckboxTableViewer;

import org.eclipse.jface.viewers.ICheckStateListener;

import org.eclipse.jface.viewers.ISelectionChangedListener;

import org.eclipse.jface.viewers.IStructuredSelection;

import org.eclipse.jface.viewers.LabelProvider;

import org.eclipse.jface.viewers.SelectionChangedEvent;

import com.nokia.carbide.search.system.internal.ui.SearchPlugin;

import com.nokia.carbide.search.system.ui.NewSearchUI;

import com.nokia.carbide.search.system.ui.text.MatchFilter;

/**

 * A dialog that lets users configure the active {@link MatchFilter match filters} and (optionally) the

 * maximal number of top level elements.

 * 

 * @since 3.3

 */

public class MatchFilterSelectionDialog extends StatusDialog {

	private final boolean fShowLimitConfigurationControls;

	private final MatchFilter[] fAllFilters;

	private MatchFilter[] fEnabledFilters;

	private CheckboxTableViewer fListViewer;

	private Button fLimitElementsCheckbox;

	private Text fLimitElementsField;

	private Text fDescription;

	private int fLimitElementCount;

	private int fLastLimit;

	private final boolean fEnableMatchFilterConfiguration;

	/**

	 * Creates a {@link MatchFilterSelectionDialog}.

	 * 

	 * @param shell the parent shell

	 * @param enableMatchFilterConfiguration 

	 * @param allFilters all filters available for selection

	 * @param selectedFilters the initially selected filters

	 * @param enableLimitConfiguration if set, the dialog will also contain controls to limit

	 * the number of top level elements

	 * @param limit the initial limit or -1 if no limit should be used.

	 */

	public MatchFilterSelectionDialog(Shell shell, boolean enableMatchFilterConfiguration, MatchFilter[] allFilters, MatchFilter[] selectedFilters, boolean enableLimitConfiguration, int limit) {

		super(shell);

		setTitle(SearchMessages.MatchFilterSelectionDialog_label);

		setStatusLineAboveButtons(true);

		fShowLimitConfigurationControls= enableLimitConfiguration;

		fEnableMatchFilterConfiguration= enableMatchFilterConfiguration;

		fAllFilters= allFilters;

		fEnabledFilters= selectedFilters;

		fLimitElementCount= limit;

		fLastLimit= limit != -1 ? limit : 1000;

	}

	/* (non-Javadoc)

	 * @see org.eclipse.jface.dialogs.Dialog#isResizable()

	 * @since 3.4

	 */

	protected boolean isResizable() {

		return true;

	}

	/* (non-Javadoc)

	 * @see org.eclipse.jface.dialogs.Dialog#getDialogBoundsSettings()

	 */

	protected IDialogSettings getDialogBoundsSettings() {

		String name= "MatchFilterSelectionDialog_" + String.valueOf(fShowLimitConfigurationControls) + '.' + String.valueOf(fEnableMatchFilterConfiguration); //$NON-NLS-1$

		return SearchPlugin.getDefault().getDialogSettingsSection(name);

	}

	/**

	 * Returns the currently selected match filters.

	 * 

	 * @return the currently selected match filters.

	 */

	public MatchFilter[] getMatchFilters() {

		return fEnabledFilters;

	}

	/**

	 * Returns the currently configured limit for top level elements. <code>-1</code> is returned if

	 * no limit should be applied.

	 * 

	 * @return the currently configured limit for top level elements or -1 if no limit should be used.

	 */

	public int getLimit() {

		return fLimitElementCount;

	}

	/* (non-Javadoc)

	 * @see org.eclipse.jface.dialogs.Dialog#createDialogArea(org.eclipse.swt.widgets.Composite)

	 */

	protected Control createDialogArea(Composite composite) {

		Composite parent = (Composite) super.createDialogArea(composite);

		initializeDialogUnits(composite);

		if (fShowLimitConfigurationControls) {

			createTableLimit(parent);

		}

		if (fEnableMatchFilterConfiguration) {

			createMatchFilterControls(parent);

		}

		return parent;

	}

	private void createMatchFilterControls(Composite parent) {

		// Create list viewer

		Label l= new Label(parent, SWT.NONE);

		l.setFont(parent.getFont());

		l.setText(SearchMessages.MatchFilterSelectionDialog_filter_description); 

		Table table = new Table(parent, SWT.CHECK | SWT.BORDER);

		table.setFont(parent.getFont());

		fListViewer = new CheckboxTableViewer(table);

		GridData data = new GridData(GridData.FILL_BOTH);

		data.minimumHeight= convertHeightInCharsToPixels(8);

		table.setLayoutData(data);

		class ListenerAndLabelProvider extends LabelProvider implements ISelectionChangedListener, ICheckStateListener {

			public void selectionChanged(SelectionChangedEvent event) {

				performFilterListSelectionChanged();

			}

			public void checkStateChanged(CheckStateChangedEvent event) {

				performFilterListCheckStateChanged();

			}

			public String getText(Object element) {

				return ((MatchFilter) element).getName();

			}

		}

		ListenerAndLabelProvider listenerAndLP= new ListenerAndLabelProvider();

		fListViewer.setLabelProvider(listenerAndLP);

		fListViewer.setContentProvider(new ArrayContentProvider());

		fListViewer.addSelectionChangedListener(listenerAndLP);

		fListViewer.addCheckStateListener(listenerAndLP);

		fListViewer.setInput(fAllFilters);

		fListViewer.setCheckedElements(fEnabledFilters);

		l= new Label(parent, SWT.NONE);

		l.setFont(parent.getFont());

		l.setText(SearchMessages.MatchFilterSelectionDialog_description_label); 

		fDescription = new Text(parent, SWT.LEFT | SWT.WRAP | SWT.MULTI | SWT.READ_ONLY | SWT.BORDER | SWT.V_SCROLL);

		fDescription.setFont(parent.getFont());

		data = new GridData(GridData.FILL_HORIZONTAL);

		data.heightHint = convertHeightInCharsToPixels(3);

		fDescription.setLayoutData(data);

	}

	private void createTableLimit(Composite ancestor) {

		Composite parent = new Composite(ancestor, SWT.NONE);

		parent.setFont(ancestor.getFont());

		GridLayout gl = new GridLayout();

		gl.numColumns = 2;

		gl.marginWidth = 0;

		gl.marginHeight = 0;

		parent.setLayout(gl);

		GridData gd = new GridData();

		gd.horizontalSpan = 2;

		parent.setLayoutData(gd);

		fLimitElementsCheckbox = new Button(parent, SWT.CHECK);

		fLimitElementsCheckbox.setText(SearchMessages.MatchFilterSelectionDialog_limit_description);  

		fLimitElementsCheckbox.setLayoutData(new GridData());

		fLimitElementsCheckbox.setFont(parent.getFont());

		fLimitElementsField = new Text(parent, SWT.BORDER);

		fLimitElementsField.setFont(parent.getFont());

		gd = new GridData();

		gd.widthHint = convertWidthInCharsToPixels(6);

		fLimitElementsField.setLayoutData(gd);

		fLimitElementsCheckbox.addSelectionListener(new SelectionAdapter() {

			public void widgetSelected(SelectionEvent e) {

				performLimitCheckboxChanged();

			}

		});

		fLimitElementsField.addModifyListener(new ModifyListener() {

			public void modifyText(ModifyEvent e) {

				performLimitTextModified();

			}

		});

		fLimitElementsCheckbox.setSelection(fLimitElementCount != -1);

		fLimitElementsField.setText(String.valueOf(fLastLimit));

		fLimitElementsField.setEnabled(fLimitElementsCheckbox.getSelection());

	}

	private void performFilterListSelectionChanged() {

		Object selectedElement = ((IStructuredSelection) fListViewer.getSelection()).getFirstElement();

		if (selectedElement != null)

			fDescription.setText(((MatchFilter) selectedElement).getDescription());

		else

			fDescription.setText(new String());

	}

	private void performFilterListCheckStateChanged() {

		Object[] checked= fListViewer.getCheckedElements();

		fEnabledFilters= new MatchFilter[checked.length];

		System.arraycopy(checked, 0, fEnabledFilters, 0, checked.length);

	}

	private void performLimitCheckboxChanged() {

		fLimitElementsField.setEnabled(fLimitElementsCheckbox.getSelection());

		fLimitElementCount= fLimitElementsCheckbox.getSelection() ? fLastLimit : -1;

		performLimitTextModified();

	}

	private void performLimitTextModified() {

		String text = fLimitElementsField.getText();

		int value = -1;

		try {

			value = Integer.valueOf(text).intValue();

		} catch (NumberFormatException e) {

		}

		fLimitElementCount= value;

		if (fLimitElementsCheckbox.getSelection() && value <= 0)

			updateStatus(createStatus(IStatus.ERROR, SearchMessages.MatchFilterSelectionDialog_error_invalid_limit)); 

		else

			updateStatus(createStatus(IStatus.OK, "")); //$NON-NLS-1$

	}

	private IStatus createStatus(int severity, String message) {

		return new Status(severity, NewSearchUI.PLUGIN_ID, severity, message, null);

	}

}