/* dtkFlowLayout.cpp ---
 *
 * Author: Julien Wintz
 * Copyright (C) 2008-2011 - Julien Wintz, Inria.
 * Created: Tue Nov 29 00:03:40 2011 (+0100)
 * Version: $Id: cc42d078558141dcdfda5bfa6a5bf506983d26cf $
 * Last-Updated: Tue Feb 28 12:27:33 2012 (+0100)
 *           By: Julien Wintz
 *     Update #: 4
 */

/* Commentary:
 * See credits at EOF
 */

/* Change log:
 *
 */

#include "dtkFlowLayout.h"

dtkFlowLayout::dtkFlowLayout(QWidget *parent, int margin, int hSpacing, int vSpacing)
    : QLayout(parent), m_hSpace(hSpacing), m_vSpace(vSpacing)
{
    setContentsMargins(margin, margin, margin, margin);
}

dtkFlowLayout::dtkFlowLayout(int margin, int hSpacing, int vSpacing)
    : m_hSpace(hSpacing), m_vSpace(vSpacing)
{
    setContentsMargins(margin, margin, margin, margin);
}

dtkFlowLayout::~dtkFlowLayout()
{
    QLayoutItem *item;

    while ((item = takeAt(0)))
        delete item;
}

void dtkFlowLayout::addItem(QLayoutItem *item)
{
    itemList.append(item);
}

int dtkFlowLayout::horizontalSpacing() const
{
    if (m_hSpace >= 0) {
        return m_hSpace;
    } else {
        return smartSpacing(QStyle::PM_LayoutHorizontalSpacing);
    }
}

int dtkFlowLayout::verticalSpacing() const
{
    if (m_vSpace >= 0) {
        return m_vSpace;
    } else {
        return smartSpacing(QStyle::PM_LayoutVerticalSpacing);
    }
}

int dtkFlowLayout::count() const
{
    return itemList.size();
}

QLayoutItem *dtkFlowLayout::itemAt(int index) const
{
    return itemList.value(index);
}

QLayoutItem *dtkFlowLayout::takeAt(int index)
{
    if (index >= 0 && index < itemList.size())
        return itemList.takeAt(index);
    else
        return 0;
}

Qt::Orientations dtkFlowLayout::expandingDirections() const
{
    return 0;
}

bool dtkFlowLayout::hasHeightForWidth() const
{
    return true;
}

int dtkFlowLayout::heightForWidth(int width) const
{
    int height = doLayout(QRect(0, 0, width, 0), true);
    return height;
}

void dtkFlowLayout::setGeometry(const QRect& rect)
{
    QLayout::setGeometry(rect);
    doLayout(rect, false);
}

QSize dtkFlowLayout::sizeHint() const
{
    return minimumSize();
}

QSize dtkFlowLayout::minimumSize() const
{
    QSize size;
    QLayoutItem *item;

    foreach (item, itemList)
        size = size.expandedTo(item->minimumSize());

    size += QSize(2 * margin(), 2 * margin());
    return size;
}

int dtkFlowLayout::doLayout(const QRect& rect, bool testOnly) const
{
    int left, top, right, bottom;
    getContentsMargins(&left, &top, &right, &bottom);
    QRect effectiveRect = rect.adjusted(+left, +top, -right, -bottom);
    int x = effectiveRect.x();
    int y = effectiveRect.y();
    int lineHeight = 0;

    QLayoutItem *item;

    foreach (item, itemList) {
        QWidget *wid = item->widget();
        int spaceX = horizontalSpacing();

        if (spaceX == -1)
            spaceX = wid->style()->layoutSpacing(
                         QSizePolicy::PushButton, QSizePolicy::PushButton, Qt::Horizontal);

        int spaceY = verticalSpacing();

        if (spaceY == -1)
            spaceY = wid->style()->layoutSpacing(
                         QSizePolicy::PushButton, QSizePolicy::PushButton, Qt::Vertical);

        int nextX = x + item->sizeHint().width() + spaceX;

        if (nextX - spaceX > effectiveRect.right() && lineHeight > 0) {
            x = effectiveRect.x();
            y = y + lineHeight + spaceY;
            nextX = x + item->sizeHint().width() + spaceX;
            lineHeight = 0;
        }

        if (!testOnly)
            item->setGeometry(QRect(QPoint(x, y), item->sizeHint()));

        x = nextX;
        lineHeight = qMax(lineHeight, item->sizeHint().height());
    }

    return y + lineHeight - rect.y() + bottom;
}

int dtkFlowLayout::smartSpacing(QStyle::PixelMetric pm) const
{
    QObject *parent = this->parent();

    if (!parent) {
        return -1;
    } else if (parent->isWidgetType()) {
        QWidget *pw = static_cast<QWidget *>(parent);
        return pw->style()->pixelMetric(pm, 0, pw);
    } else {
        return static_cast<QLayout *>(parent)->spacing();
    }
}

// /////////////////////////////////////////////////////////////////
// Credits
// /////////////////////////////////////////////////////////////////

/****************************************************************************
**
** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).
** All rights reserved.
** Contact: Nokia Corporation (qt-info@nokia.com)
**
** This file is part of the examples of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:BSD$
** You may use this file under the terms of the BSD license as follows:
**
** "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 Nokia Corporation and its Subsidiary(-ies) 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 THE COPYRIGHT
** OWNER OR CONTRIBUTORS 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."
** $QT_END_LICENSE$
**
****************************************************************************/