Carla/source/modules/juce_gui_basics/layout/juce_ResizableBorderComponent.cpp

/*
  ==============================================================================

   This file is part of the JUCE 6 technical preview.
   Copyright (c) 2017 - ROLI Ltd.

   You may use this code under the terms of the GPL v3
   (see www.gnu.org/licenses).

   For this technical preview, this file is not subject to commercial licensing.

   JUCE IS PROVIDED "AS IS" WITHOUT ANY WARRANTY, AND ALL WARRANTIES, WHETHER
   EXPRESSED OR IMPLIED, INCLUDING MERCHANTABILITY AND FITNESS FOR PURPOSE, ARE
   DISCLAIMED.

  ==============================================================================
*/

namespace juce
{

ResizableBorderComponent::Zone::Zone() noexcept {}
ResizableBorderComponent::Zone::Zone (int zoneFlags) noexcept  : zone (zoneFlags) {}
ResizableBorderComponent::Zone::Zone (const ResizableBorderComponent::Zone& other) noexcept  : zone (other.zone) {}

ResizableBorderComponent::Zone& ResizableBorderComponent::Zone::operator= (const ResizableBorderComponent::Zone& other) noexcept
{
    zone = other.zone;
    return *this;
}

bool ResizableBorderComponent::Zone::operator== (const ResizableBorderComponent::Zone& other) const noexcept      { return zone == other.zone; }
bool ResizableBorderComponent::Zone::operator!= (const ResizableBorderComponent::Zone& other) const noexcept      { return zone != other.zone; }

ResizableBorderComponent::Zone ResizableBorderComponent::Zone::fromPositionOnBorder (Rectangle<int> totalSize,
                                                                                     BorderSize<int> border,
                                                                                     Point<int> position)
{
    int z = 0;

    if (totalSize.contains (position)
         && ! border.subtractedFrom (totalSize).contains (position))
    {
        auto minW = jmax (totalSize.getWidth() / 10, jmin (10, totalSize.getWidth() / 3));

        if (position.x < jmax (border.getLeft(), minW) && border.getLeft() > 0)
            z |= left;
        else if (position.x >= totalSize.getWidth() - jmax (border.getRight(), minW) && border.getRight() > 0)
            z |= right;

        auto minH = jmax (totalSize.getHeight() / 10, jmin (10, totalSize.getHeight() / 3));

        if (position.y < jmax (border.getTop(), minH) && border.getTop() > 0)
            z |= top;
        else if (position.y >= totalSize.getHeight() - jmax (border.getBottom(), minH) && border.getBottom() > 0)
            z |= bottom;
    }

    return Zone (z);
}

MouseCursor ResizableBorderComponent::Zone::getMouseCursor() const noexcept
{
    auto mc = MouseCursor::NormalCursor;

    switch (zone)
    {
        case (left | top):      mc = MouseCursor::TopLeftCornerResizeCursor; break;
        case top:               mc = MouseCursor::TopEdgeResizeCursor; break;
        case (right | top):     mc = MouseCursor::TopRightCornerResizeCursor; break;
        case left:              mc = MouseCursor::LeftEdgeResizeCursor; break;
        case right:             mc = MouseCursor::RightEdgeResizeCursor; break;
        case (left | bottom):   mc = MouseCursor::BottomLeftCornerResizeCursor; break;
        case bottom:            mc = MouseCursor::BottomEdgeResizeCursor; break;
        case (right | bottom):  mc = MouseCursor::BottomRightCornerResizeCursor; break;
        default:                break;
    }

    return mc;
}

//==============================================================================
ResizableBorderComponent::ResizableBorderComponent (Component* componentToResize,
                                                    ComponentBoundsConstrainer* boundsConstrainer)
   : component (componentToResize),
     constrainer (boundsConstrainer),
     borderSize (5)
{
}

ResizableBorderComponent::~ResizableBorderComponent() = default;

//==============================================================================
void ResizableBorderComponent::paint (Graphics& g)
{
    getLookAndFeel().drawResizableFrame (g, getWidth(), getHeight(), borderSize);
}

void ResizableBorderComponent::mouseEnter (const MouseEvent& e)
{
    updateMouseZone (e);
}

void ResizableBorderComponent::mouseMove (const MouseEvent& e)
{
    updateMouseZone (e);
}

void ResizableBorderComponent::mouseDown (const MouseEvent& e)
{
    if (component == nullptr)
    {
        jassertfalse; // You've deleted the component that this resizer was supposed to be using!
        return;
    }

    updateMouseZone (e);

    originalBounds = component->getBounds();

    if (constrainer != nullptr)
        constrainer->resizeStart();
}

void ResizableBorderComponent::mouseDrag (const MouseEvent& e)
{
    if (component == nullptr)
    {
        jassertfalse; // You've deleted the component that this resizer was supposed to be using!
        return;
    }

    auto newBounds = mouseZone.resizeRectangleBy (originalBounds, e.getOffsetFromDragStart());

    if (constrainer != nullptr)
    {
        constrainer->setBoundsForComponent (component, newBounds,
                                            mouseZone.isDraggingTopEdge(),
                                            mouseZone.isDraggingLeftEdge(),
                                            mouseZone.isDraggingBottomEdge(),
                                            mouseZone.isDraggingRightEdge());
    }
    else
    {
        if (auto* p = component->getPositioner())
            p->applyNewBounds (newBounds);
        else
            component->setBounds (newBounds);
    }
}

void ResizableBorderComponent::mouseUp (const MouseEvent&)
{
    if (constrainer != nullptr)
        constrainer->resizeEnd();
}

bool ResizableBorderComponent::hitTest (int x, int y)
{
    return ! borderSize.subtractedFrom (getLocalBounds()).contains (x, y);
}

void ResizableBorderComponent::setBorderThickness (BorderSize<int> newBorderSize)
{
    if (borderSize != newBorderSize)
    {
        borderSize = newBorderSize;
        repaint();
    }
}

BorderSize<int> ResizableBorderComponent::getBorderThickness() const
{
    return borderSize;
}

void ResizableBorderComponent::updateMouseZone (const MouseEvent& e)
{
    auto newZone = Zone::fromPositionOnBorder (getLocalBounds(), borderSize, e.getPosition());

    if (mouseZone != newZone)
    {
        mouseZone = newZone;
        setMouseCursor (newZone.getMouseCursor());
    }
}

} // namespace juce