/*******************************************************************************
 * 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 v. 2.0 which is available at
 * http://www.eclipse.org/legal/epl-2.0.
 * 
 * SPDX-License-Identifier: EPL-2.0
 *
 *******************************************************************************/
package org.eclipse.dltk.internal.ui.callhierarchy;

import org.eclipse.dltk.internal.corext.callhierarchy.MethodWrapper;
import org.eclipse.jface.action.IMenuListener;
import org.eclipse.jface.action.MenuManager;
import org.eclipse.jface.viewers.ISelectionProvider;
import org.eclipse.jface.viewers.StructuredSelection;
import org.eclipse.jface.viewers.TreeViewer;
import org.eclipse.swt.SWT;
import org.eclipse.swt.events.KeyListener;
import org.eclipse.swt.layout.GridData;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Menu;
import org.eclipse.swt.widgets.Tree;
import org.eclipse.ui.IWorkbenchPartSite;


class CallHierarchyViewer extends TreeViewer {
    private CallHierarchyViewPart fPart;

    private OpenLocationAction fOpen;

    private CallHierarchyContentProvider fContentProvider;

    /**
     * @param parent
     */
    CallHierarchyViewer(Composite parent, CallHierarchyViewPart part) {
        super(new Tree(parent, SWT.MULTI));

        fPart = part;

        getControl().setLayoutData(new GridData(GridData.FILL_BOTH));
        setUseHashlookup(true);
        setAutoExpandLevel(2);
        fContentProvider = new CallHierarchyContentProvider(fPart);
        setContentProvider(fContentProvider);
        setLabelProvider(new CallHierarchyLabelProvider());

        fOpen= new OpenLocationAction(part, part.getSite());
		addOpenListener(event -> fOpen.run());

        clearViewer();
    }

    /**
     * @param wrapper
     */
    void setMethodWrapper(MethodWrapper wrapper) {
        setInput(getTreeRoot(wrapper));

        setFocus();
        setSelection(new StructuredSelection(wrapper), true);
    }

    CallHierarchyViewPart getPart() {
        return fPart;
    }

    /**
     *
     */
    void setFocus() {
        getControl().setFocus();
    }

    boolean isInFocus() {
        return getControl().isFocusControl();
    }

    /**
     * @param keyListener
     */
    void addKeyListener(KeyListener keyListener) {
        getControl().addKeyListener(keyListener);
    }

    /**
     * Wraps the root of a MethodWrapper tree in a dummy root in order to show
     * it in the tree.
     *
     * @param root The root of the MethodWrapper tree.
     * @return A new MethodWrapper which is a dummy root above the specified root.
     */
    private TreeRoot getTreeRoot(MethodWrapper root) {
        TreeRoot dummyRoot = new TreeRoot(root);

        return dummyRoot;
    }

    /**
     * Attaches a contextmenu listener to the tree
     */
    void initContextMenu(IMenuListener menuListener, IWorkbenchPartSite viewSite, ISelectionProvider selectionProvider) {
        MenuManager menuMgr= new MenuManager();
        menuMgr.setRemoveAllWhenShown(true);
        menuMgr.addMenuListener(menuListener);
        Menu menu= menuMgr.createContextMenu(getTree());
        getTree().setMenu(menu);
        viewSite.registerContextMenu(menuMgr, selectionProvider);
    }

    /**
     *
     */
    void clearViewer() {
        setInput(TreeRoot.EMPTY_ROOT);
    }

    void cancelJobs() {
    	if (fPart == null)
    		return;
        fContentProvider.cancelJobs(fPart.getCurrentMethodWrapper());
    }
}