/****************************************************************************
**
** Copyright (C) 2013 Digia Plc and/or its subsidiary(-ies).
** Contact: http://www.qt-project.org/legal
**
** This file is part of Qt Creator.
**
** Commercial License Usage
** Licensees holding valid commercial Qt licenses may use this file in
** accordance with the commercial license agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and Digia.  For licensing terms and
** conditions see http://qt.digia.com/licensing.  For further information
** use the contact form at http://qt.digia.com/contact-us.
**
** GNU Lesser General Public License Usage
** Alternatively, this file may be used under the terms of the GNU Lesser
** General Public License version 2.1 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPL included in the
** packaging of this file.  Please review the following information to
** ensure the GNU Lesser General Public License version 2.1 requirements
** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
**
** In addition, as a special exception, Digia gives you certain additional
** rights.  These rights are described in the Digia Qt LGPL Exception
** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
**
****************************************************************************/

#include "formresizer.h"
#include "sizehandlerect.h"
#include "widgethostconstants.h"

#include <QDebug>

#include <QDesignerFormWindowInterface>

#include <QResizeEvent>
#include <QPalette>
#include <QLayout>
#include <QFrame>

enum { debugFormResizer = 0 };

using namespace SharedTools::Internal;

FormResizer::FormResizer(QWidget *parent) :
    QWidget(parent),
    m_frame(new QFrame),
    m_formWindow(0)
{
    // Make the resize grip of a mainwindow form find us as resizable window.
    setWindowFlags(windowFlags() | Qt::SubWindow);
    setBackgroundRole(QPalette::Base);

    QVBoxLayout *handleLayout = new QVBoxLayout(this);
    handleLayout->setMargin(SELECTION_MARGIN);
    handleLayout->addWidget(m_frame);

    m_frame->setFrameStyle(QFrame::Panel | QFrame::Raised);
    QVBoxLayout *layout = new QVBoxLayout(m_frame);
    layout->setMargin(0);
    // handles
    m_handles.reserve(SizeHandleRect::Left);
    for (int i = SizeHandleRect::LeftTop; i <= SizeHandleRect::Left; ++i) {
        SizeHandleRect *shr = new SizeHandleRect(this, static_cast<SizeHandleRect::Direction>(i), this);
        connect(shr, SIGNAL(mouseButtonReleased(QRect,QRect)), this, SIGNAL(formWindowSizeChanged(QRect,QRect)));
        m_handles.push_back(shr);
    }
    setState(SelectionHandleActive);
    updateGeometry();
}

void FormResizer::updateGeometry()
{
    const QRect &geom = m_frame->geometry();

    if (debugFormResizer)
        qDebug() << "FormResizer::updateGeometry() " << size() << " frame " << geom;

    const int w = SELECTION_HANDLE_SIZE;
    const int h = SELECTION_HANDLE_SIZE;

    const Handles::iterator hend =  m_handles.end();
    for (Handles::iterator it = m_handles.begin(); it != hend; ++it) {
        SizeHandleRect *hndl = *it;
        switch (hndl->dir()) {
        case SizeHandleRect::LeftTop:
            hndl->move(geom.x() - w / 2, geom.y() - h / 2);
            break;
        case SizeHandleRect::Top:
            hndl->move(geom.x() + geom.width() / 2 - w / 2, geom.y() - h / 2);
            break;
        case SizeHandleRect::RightTop:
            hndl->move(geom.x() + geom.width() - w / 2, geom.y() - h / 2);
            break;
        case SizeHandleRect::Right:
            hndl->move(geom.x() + geom.width() - w / 2, geom.y() + geom.height() / 2 - h / 2);
            break;
        case SizeHandleRect::RightBottom:
            hndl->move(geom.x() + geom.width() - w / 2, geom.y() + geom.height() - h / 2);
            break;
        case SizeHandleRect::Bottom:
            hndl->move(geom.x() + geom.width() / 2 - w / 2, geom.y() + geom.height() - h / 2);
            break;
        case SizeHandleRect::LeftBottom:
            hndl->move(geom.x() - w / 2, geom.y() + geom.height() - h / 2);
            break;
        case SizeHandleRect::Left:
            hndl->move(geom.x() - w / 2, geom.y() + geom.height() / 2 - h / 2);
            break;
        default:
            break;
        }
    }
}

void FormResizer::update()
{
    const Handles::iterator hend =  m_handles.end();
    for (Handles::iterator it = m_handles.begin(); it != hend; ++it) {
        (*it)->update();
    }
}

void FormResizer::setState(SelectionHandleState st)
{
    if (debugFormResizer)
        qDebug() << "FormResizer::setState " << st;

    const Handles::iterator hend =  m_handles.end();
    for (Handles::iterator it = m_handles.begin(); it != hend; ++it)
        (*it)->setState(st);
}

void FormResizer::setFormWindow(QDesignerFormWindowInterface *fw)
{
    if (debugFormResizer)
        qDebug() << "FormResizer::setFormWindow " << fw;
    QVBoxLayout *layout = qobject_cast<QVBoxLayout *>(m_frame->layout());
    Q_ASSERT(layout);
    if (layout->count())
        delete layout->takeAt(0);
    m_formWindow = fw;

    if (m_formWindow)
        layout->addWidget(m_formWindow);
    mainContainerChanged();
     connect(fw, SIGNAL(mainContainerChanged(QWidget*)), this, SLOT(mainContainerChanged()));
}

void FormResizer::resizeEvent(QResizeEvent *event)
{
    if (debugFormResizer)
        qDebug() << ">FormResizer::resizeEvent" <<  event->size();
    updateGeometry();
    QWidget::resizeEvent(event);
    if (debugFormResizer)
        qDebug() << "<FormResizer::resizeEvent";
}

QSize FormResizer::decorationSize() const
{
    const int margin = 2 * SELECTION_MARGIN + 2 * m_frame->lineWidth();
    return QSize(margin, margin);
}

QWidget *FormResizer::mainContainer()
{
    if (m_formWindow)
        return m_formWindow->mainContainer();
    return 0;
}

void FormResizer::mainContainerChanged()
{
    const QSize maxWidgetSize = QSize(QWIDGETSIZE_MAX, QWIDGETSIZE_MAX);
    if (const QWidget *mc = mainContainer()) {
        // Set Maximum size which is not handled via a hint (as opposed to minimum size)
        const QSize maxWidgetSize = QSize(QWIDGETSIZE_MAX, QWIDGETSIZE_MAX);
        const QSize formMaxSize = mc->maximumSize();
        QSize newMaxSize = maxWidgetSize;
        if (formMaxSize != maxWidgetSize)
            newMaxSize = formMaxSize + decorationSize();
        if (debugFormResizer)
            qDebug() << "FormResizer::mainContainerChanged" <<  mc << " Size " << mc->size()<< newMaxSize;
        setMaximumSize(newMaxSize);
        resize(decorationSize() + mc->size());
    } else {
        setMaximumSize(maxWidgetSize);
    }
}