/*******************************************************************************
 * Copyright (c) 2000, 2017 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
 *******************************************************************************/
package org.eclipse.team.internal.ui.dialogs;

import org.eclipse.core.resources.mapping.ResourceMapping;
import org.eclipse.jface.viewers.CheckboxTableViewer;
import org.eclipse.jface.viewers.ISelection;
import org.eclipse.jface.viewers.IStructuredSelection;
import org.eclipse.jface.viewers.TableViewer;
import org.eclipse.swt.SWT;
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.Table;
import org.eclipse.team.internal.ui.TeamUIMessages;
import org.eclipse.team.internal.ui.mapping.ResourceMappingLabelProvider;
import org.eclipse.ui.model.AdaptableList;
import org.eclipse.ui.model.BaseWorkbenchContentProvider;

/**
 * Dialog area that displays a checkbox list of mappings.
 */
public class ResourceMappingSelectionArea extends DialogArea {

	/**
     * Property constant used to indicate that the selected mapping has changed.
     * The object associated with the property is a <code>ResourceMapping</code>.
     */
    public static final String SELECTED_MAPPING = "SelectedMapping"; //$NON-NLS-1$

    /**
     * Property constant used to indicate that the checked mappings have changed.
     * The object associated with the property is a <code>ResourceMapping[]</code>
     * (i.e. an array of mappings).
     */
    public static final String CHECKED_MAPPINGS = "CheckedMappings"; //$NON-NLS-1$

    private ResourceMapping[] mappings;
    private TableViewer viewer;
    private ResourceMapping[] checkedMappings;
    private ResourceMapping selectedMapping;
    private String description;
	private boolean supportsChecking;
	private boolean supportsSelection;

    public ResourceMappingSelectionArea(ResourceMapping[] mappings, boolean supportSelection, boolean supportChecking) {
        this.mappings = mappings;
        this.supportsChecking = supportChecking;
        this.supportsSelection = supportSelection;
    }

    @Override
	public void createArea(Composite parent) {
        Composite composite = createComposite(parent, 1, true);
        GridLayout layout = new GridLayout(1, false);
        layout.marginHeight = 0;
        layout.marginWidth = 0;
        layout.verticalSpacing = 0;
        layout.horizontalSpacing = 0;
        composite.setLayout(layout);

        if (description != null)
            createWrappingLabel(composite, description, 1);

        createViewer(composite);
        GridData data = new GridData(GridData.FILL_BOTH);
        data.heightHint = 100;
        data.widthHint = 300;
        viewer.getControl().setLayoutData(data);
        viewer.setContentProvider(new BaseWorkbenchContentProvider());
        viewer.setLabelProvider(new ResourceMappingLabelProvider());
        viewer.setInput(new AdaptableList(mappings));
        if (isSupportsSelection()) {
	        viewer.addSelectionChangedListener(event -> {
			    ResourceMapping oldSelection = selectedMapping;
			    selectedMapping = internalGetSelectedMapping();
			    if (oldSelection != selectedMapping)
			        firePropertyChangeChange(SELECTED_MAPPING, oldSelection, selectedMapping);
			});
        }
        if (isSupportsChecking())
        	initializeCheckboxViewer(composite);
    }

	private void initializeCheckboxViewer(Composite composite) {
		final CheckboxTableViewer checkboxViewer = getCheckboxTableViewer();
		checkboxViewer.addCheckStateListener(event -> {
			ResourceMapping[] oldMappings = checkedMappings;
			checkedMappings = internalGetCheckedMappings();
			if (oldMappings != checkedMappings)
				firePropertyChangeChange(CHECKED_MAPPINGS, oldMappings, checkedMappings);
		});
		checkboxViewer.setCheckedElements(mappings);
        checkedMappings = mappings;

        Composite buttons = createEmbeddedButtonComposite(composite);

        Button selectAll = new Button(buttons, SWT.PUSH);
        selectAll.setText(TeamUIMessages.ResourceMappingSelectionArea_0);
        selectAll.setLayoutData(new GridData(GridData.FILL_BOTH));
        selectAll.addSelectionListener(new SelectionAdapter() {
            @Override
			public void widgetSelected(SelectionEvent e) {
            	checkboxViewer.setAllChecked(true);
            }
        });

        Button deselectAll = new Button(buttons, SWT.PUSH);
        deselectAll.setText(TeamUIMessages.ResourceMappingSelectionArea_1);
        deselectAll.setLayoutData(new GridData(GridData.FILL_BOTH));
        deselectAll.addSelectionListener(new SelectionAdapter() {
            @Override
			public void widgetSelected(SelectionEvent e) {
            	checkboxViewer.setAllChecked(false);
            }
        });
	}

	private void createViewer(Composite composite) {
		if (isSupportsChecking())
			viewer = CheckboxTableViewer.newCheckList(composite, getViewerStyle());
		else
			viewer = new TableViewer(new Table(composite, getViewerStyle()));
	}

	private int getViewerStyle() {
		int style = SWT.BORDER;
		if (isSupportsSelection())
			style |= SWT.SINGLE;
		return style;
	}

    /* private */ ResourceMapping[] internalGetCheckedMappings() {
        Object[] checked = getCheckboxTableViewer().getCheckedElements();
        ResourceMapping[] mappings = new ResourceMapping[checked.length];
        for (int i = 0; i < checked.length; i++) {
            Object object = checked[i];
            mappings[i] = (ResourceMapping)object;
        }
        return mappings;
    }

    private Composite createEmbeddedButtonComposite(Composite composite) {
        GridData data;
        Composite buttons = new Composite(composite, SWT.NONE);
        GridLayout layout = new GridLayout();
        layout.numColumns = 2; // this is incremented by createButton
        layout.makeColumnsEqualWidth = true;
        layout.marginWidth = 0;
        buttons.setLayout(layout);
        data = new GridData(GridData.HORIZONTAL_ALIGN_END
                | GridData.VERTICAL_ALIGN_CENTER);
        buttons.setLayoutData(data);
        return buttons;
    }

    /* private */ ResourceMapping internalGetSelectedMapping() {
        ISelection selection = viewer.getSelection();
        if (selection instanceof IStructuredSelection) {
            IStructuredSelection ss = (IStructuredSelection) selection;
            Object firstElement = ss.getFirstElement();
            if (firstElement instanceof ResourceMapping)
                return (ResourceMapping)firstElement;
        }
        return null;
    }

    public void setDescription(String description) {
        this.description = description;
    }
    public ResourceMapping[] getCheckedMappings() {
        return checkedMappings;
    }
    public ResourceMapping getSelectedMapping() {
        return selectedMapping;
    }

    private CheckboxTableViewer getCheckboxTableViewer() {
    	return (CheckboxTableViewer)viewer;
    }

	public boolean isSupportsChecking() {
		return supportsChecking;
	}

	public boolean isSupportsSelection() {
		return supportsSelection;
	}
}
