/*
 * Copyright (c) 2011, grossmann
 * 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.layout;

import org.jowidgets.api.widgets.IContainer;
import org.jowidgets.api.widgets.IControl;
import org.jowidgets.common.types.Dimension;
import org.jowidgets.common.types.Rectangle;
import org.jowidgets.common.widgets.layout.ILayouter;
import org.jowidgets.util.Assert;

final class FillLayoutImpl implements ILayouter {

    private final IContainer container;

    private final int marginTop;
    private final int marginBottom;
    private final int marginLeft;
    private final int marginRight;

    private Dimension minSize;
    private Dimension preferredSize;

    private Dimension controlMinSize;

    FillLayoutImpl(
        final IContainer container,
        final int marginLeft,
        final int marginRight,
        final int marginTop,
        final int marginBottom) {
        Assert.paramNotNull(container, "container");
        this.container = container;

        this.marginTop = marginTop;
        this.marginLeft = marginLeft;
        this.marginRight = marginRight;
        this.marginBottom = marginBottom;
    }

    @Override
    public void layout() {
        final IControl control = getFirstControl();
        if (control != null) {
            final Rectangle clientArea = container.getClientArea();

            control.setPosition(clientArea.getX() + marginLeft, clientArea.getY() + marginTop);

            final Dimension clientSize = clientArea.getSize();
            final Dimension ctrlMinSize = getControlMinSize();

            final int marginH = marginLeft + marginRight;
            final int marginV = marginBottom + marginTop;

            final int width;
            final int height;

            if (marginH < 0) {
                width = clientSize.getWidth() - marginH;
            }
            else {
                width = Math.max(ctrlMinSize.getWidth(), clientSize.getWidth() - marginH);
            }

            if (marginV < 0) {
                height = clientSize.getHeight() - marginV;
            }
            else {
                height = Math.max(ctrlMinSize.getHeight(), clientSize.getHeight() - marginV);
            }

            control.setSize(width, height);
        }
    }

    @Override
    public Dimension getMinSize() {
        if (minSize == null) {
            this.minSize = calcMinSize();
        }
        return minSize;
    }

    @Override
    public Dimension getPreferredSize() {
        if (preferredSize == null) {
            this.preferredSize = calcPreferredSize();
        }
        return preferredSize;
    }

    @Override
    public Dimension getMaxSize() {
        return Dimension.MAX;
    }

    @Override
    public void invalidate() {
        minSize = null;
        preferredSize = null;
        controlMinSize = null;
    }

    private Dimension getControlMinSize() {
        if (controlMinSize == null) {
            this.controlMinSize = getFirstControl().getMinSize();
        }
        return controlMinSize;
    }

    private Dimension calcMinSize() {
        final IControl control = getFirstControl();

        int width = marginLeft + marginRight;
        int height = marginTop + marginBottom;

        if (control != null) {
            final Dimension size = control.getMinSize();
            width = width + size.getWidth();
            height = height + size.getHeight();
        }

        return container.computeDecoratedSize(new Dimension(width, height));
    }

    private Dimension calcPreferredSize() {
        final IControl control = getFirstControl();

        int width = marginLeft + marginRight;
        int height = marginTop + marginBottom;

        if (control != null) {
            final Dimension size = control.getPreferredSize();
            width = width + size.getWidth();
            height = height + size.getHeight();
        }

        return container.computeDecoratedSize(new Dimension(width, height));
    }

    private IControl getFirstControl() {
        for (final IControl control : container.getChildren()) {
            if (control.isVisible()) {
                return control;
            }
        }
        return null;
    }
}