/*******************************************************************************
 * Copyright (c) 2011 JVM Monitor project. All rights reserved. 
 * 
 * This code is distributed under the terms of the Eclipse Public License v1.0
 * which is available at http://www.eclipse.org/legal/epl-v10.html
 *******************************************************************************/
package org.jvmmonitor.internal.ui.properties.memory;

import java.util.ArrayList;
import java.util.Collections;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import org.eclipse.jface.action.IContributionItem;
import org.eclipse.jface.action.IMenuListener;
import org.eclipse.jface.action.IMenuManager;
import org.eclipse.jface.action.IStatusLineManager;
import org.eclipse.jface.action.MenuManager;
import org.eclipse.jface.action.StatusLineContributionItem;
import org.eclipse.jface.util.Util;
import org.eclipse.swt.SWT;
import org.eclipse.swt.events.FocusEvent;
import org.eclipse.swt.events.FocusListener;
import org.eclipse.swt.layout.GridData;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Menu;
import org.eclipse.swt.widgets.TreeColumn;
import org.eclipse.ui.IActionBars;
import org.eclipse.ui.dialogs.FilteredTree;
import org.eclipse.ui.dialogs.PatternFilter;
import org.jvmmonitor.core.ISWTResourceElement;
import org.jvmmonitor.internal.ui.actions.CopyAction;

/**
 * The thread filtered tree.
 */
public class SWTResourceFilteredTree extends FilteredTree {

    /** The action bars. */
    private IActionBars actionBars;

    /**
     * The constructor.
     * 
     * @param parent
     *            The parent composite
     * @param actionBars
     *            The action bars
     */
    protected SWTResourceFilteredTree(Composite parent, IActionBars actionBars) {
        super(parent, SWT.MULTI | SWT.FULL_SELECTION, new PatternFilter(), true);
        this.actionBars = actionBars;

        configureTree();
        createContextMenu();
        setBackground(Display.getDefault().getSystemColor(SWT.COLOR_LIST_BACKGROUND));
    }

    /*
     * @see FilteredTree#createControl(Composite, int)
     */
    @Override
    protected void createControl(Composite composite, int treeStyle) {
        super.createControl(composite, treeStyle);

        // adjust the indentation of filter composite
        GridData data = (GridData) filterComposite.getLayoutData();
        data.horizontalIndent = 2;
        data.verticalIndent = 2;
        filterComposite.setLayoutData(data);
    }

    /**
     * Updates the status line.
     * 
     * @param resourceElements
     *            The SWT resource elements
     */
    public void updateStatusLine(ISWTResourceElement[] resourceElements) {
        IStatusLineManager manager = actionBars.getStatusLineManager();

        IContributionItem[] items = manager.getItems();
        StatusLineContributionItem resourceCountContributionItem = null;
        for (IContributionItem item : items) {
            if (item instanceof StatusLineContributionItem) {
                resourceCountContributionItem = (StatusLineContributionItem) item;
            }
        }

        // create the status line
        if (resourceCountContributionItem == null) {
            resourceCountContributionItem = new StatusLineContributionItem(
                    "ResourceCountContributionItem"); //$NON-NLS-1$
            manager.add(resourceCountContributionItem);
        }

        if (resourceElements == null) {
            resourceCountContributionItem.setText(Util.ZERO_LENGTH_STRING);
            return;
        }

        Map<String, Integer> resources = new HashMap<String, Integer>();
        for (ISWTResourceElement resourceElement : resourceElements) {
            String name = resourceElement.getName().split(" ")[0]; //$NON-NLS-1$
            Integer count = resources.get(name);
            resources.put(name, count == null ? 1 : ++count);
        }

        // set text on status line
        List<String> list = new ArrayList<String>(resources.keySet());
        Collections.sort(list);
        StringBuffer buffer = new StringBuffer();
        buffer.append("Total: ").append(resourceElements.length); //$NON-NLS-1$
        for (String name : list) {
            buffer.append(", ").append(name); //$NON-NLS-1$
            buffer.append(": ").append(resources.get(name)); //$NON-NLS-1$
        }
        resourceCountContributionItem.setText(buffer.toString());
    }

    /**
     * Configure the tree adding columns.
     */
    private void configureTree() {
        for (TreeColumn column : getViewer().getTree().getColumns()) {
            column.dispose();
        }

        getViewer().getTree().setLinesVisible(true);
        getViewer().getTree().setHeaderVisible(true);

        TreeColumn treeColumn = new TreeColumn(getViewer().getTree(), SWT.NONE);
        treeColumn.setText(Messages.nameColumnLabel);
        treeColumn.setWidth(500);
        treeColumn.setAlignment(SWT.LEFT);
        treeColumn.setToolTipText(Messages.nameColumnToolTip);
    }

    /**
     * Creates the context menu.
     */
    private void createContextMenu() {
        final CopyAction copyAction = CopyAction.createCopyAction(actionBars);
        getViewer().getControl().addFocusListener(new FocusListener() {
            @Override
            public void focusLost(FocusEvent e) {
                getViewer().removeSelectionChangedListener(copyAction);
            }

            @Override
            public void focusGained(FocusEvent e) {
                getViewer().addSelectionChangedListener(copyAction);
            }
        });

        MenuManager menuMgr = new MenuManager("#PopupMenu"); //$NON-NLS-1$
        menuMgr.setRemoveAllWhenShown(true);
        menuMgr.addMenuListener(new IMenuListener() {
            @Override
            public void menuAboutToShow(IMenuManager manager) {
                manager.add(copyAction);
            }
        });

        Menu menu = menuMgr.createContextMenu(getViewer().getControl());
        getViewer().getControl().setMenu(menu);
    }
}
