/*
 * Copyright (c) 2014, MGrossmann
 * All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 * * Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * * Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 * * Neither the name of the jo-widgets.org nor the
 *   names of its contributors may be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL jo-widgets.org BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
 * DAMAGE.
 */

package org.jowidgets.impl.command;

import org.jowidgets.api.command.EnabledState;
import org.jowidgets.api.command.IEnabledChecker;
import org.jowidgets.api.command.IEnabledState;
import org.jowidgets.api.widgets.ITree;
import org.jowidgets.api.widgets.ITreeContainer;
import org.jowidgets.api.widgets.ITreeNode;
import org.jowidgets.i18n.api.IMessage;
import org.jowidgets.tools.command.AbstractEnabledChecker;
import org.jowidgets.tools.controller.TreeAdapter;

final class TreeCheckedEnabledChecker extends AbstractEnabledChecker implements IEnabledChecker {

    private static final IMessage NODES_ALREADY_CHECKED = Messages.getMessage("TreeCheckedEnabledChecker.nodesAlreadyChecked");
    private static final IMessage NODES_ALREADY_UNCHECKED = Messages.getMessage("TreeCheckedEnabledChecker.nodesAlreadyUnchecked");

    private final ITreeContainer treeContainer;
    private final boolean checked;

    TreeCheckedEnabledChecker(final ITreeContainer treeContainer, final boolean checked) {
        this.treeContainer = treeContainer;
        this.checked = checked;

        getParentTree(treeContainer).addTreeListener(new TreeAdapter() {

            @Override
            public void nodeChecked(final ITreeNode node) {
                fireChangedEvent();
            }

            @Override
            public void nodeUnchecked(final ITreeNode node) {
                fireChangedEvent();
            }

        });
    }

    private static ITree getParentTree(final ITreeContainer treeContainer) {
        if (treeContainer instanceof ITree) {
            return (ITree) treeContainer;
        }
        else {
            return getParentTree(treeContainer.getParentContainer());
        }
    }

    @Override
    public IEnabledState getEnabledState() {
        if (hasNodeThatWillBeChanged(treeContainer)) {
            return EnabledState.ENABLED;
        }
        else if (checked) {
            return EnabledState.disabled(NODES_ALREADY_CHECKED.get());
        }
        else {
            return EnabledState.disabled(NODES_ALREADY_UNCHECKED.get());
        }
    }

    private boolean hasNodeThatWillBeChanged(final ITreeContainer tree) {
        for (final ITreeNode childNode : tree.getChildren()) {
            if (childNode.isChecked() != checked) {
                return true;
            }
            if (hasNodeThatWillBeChanged(childNode)) {
                return true;
            }
        }
        return false;
    }

}