#include "tcommon.h"

#include "toonzqt/pickrgbutils.h"
#include "toonzqt/screenboard.h"
#include "toonzqt/menubarcommand.h"

#include "tools/RGBpicker.h"
#include "tools/cursors.h"
#include "tools/cursormanager.h"

#include <QMouseEvent>
#include <QPaintEvent>
#include <QPainter>
#include <QCoreApplication>
#include <QCursor>
#include <QTimer>

#include "tools/screenpicker.h"

//***********************************************************************************
//    Screen Picker implementation
//***********************************************************************************

ScreenPicker::ScreenPicker(QWidget *parent)
	: m_mousePressed(false), m_mouseGrabbed(false)
{
}

//------------------------------------------------------------------

bool ScreenPicker::acceptScreenEvents(const QRect &screenRect) const
{
	return screenRect.contains(QCursor::pos()) || //Accept mouse events
		   screenRect.intersects(m_geometry);	 //Accept paint events
}

//------------------------------------------------------------------

void ScreenPicker::event(QWidget *widget, QEvent *e)
{
	switch (e->type()) {
	case QEvent::MouseButtonPress:
		mousePressEvent(widget, static_cast<QMouseEvent *>(e));
		break;

	case QEvent::MouseMove:
		mouseMoveEvent(widget, static_cast<QMouseEvent *>(e));
		break;

	case QEvent::MouseButtonRelease:
		mouseReleaseEvent(widget, static_cast<QMouseEvent *>(e));
	};
}

//------------------------------------------------------------------

void ScreenPicker::mousePressEvent(QWidget *widget, QMouseEvent *me)
{
	m_mousePressed = true;
	m_start = widget->mapToGlobal(me->pos());

	m_geometry = QRect(m_start, QSize(1, 1));
	DVGui::ScreenBoard::instance()->update();
}

//------------------------------------------------------------------

void ScreenPicker::mouseMoveEvent(QWidget *widget, QMouseEvent *me)
{
	assert(m_mouseGrabbed);
	if (!m_mousePressed)
		return;

	QPoint pos(widget->mapToGlobal(me->pos()));
	m_geometry = QRect(QRect(m_start, QSize(1, 1)) | QRect(pos, QSize(1, 1)));

	DVGui::ScreenBoard::instance()->update();
}

//------------------------------------------------------------------

void ScreenPicker::mouseReleaseEvent(QWidget *widget, QMouseEvent *me)
{
	assert(m_mouseGrabbed);
	if (!m_mousePressed)
		return;

	m_mouseGrabbed = m_mousePressed = false;

	DVGui::ScreenBoard *screenBoard = DVGui::ScreenBoard::instance();
	QList<DVGui::ScreenBoard::Drawing *> &drawings = screenBoard->drawings();

	drawings.removeAt(drawings.indexOf(this));
	screenBoard->releaseMouse();
	screenBoard->update();

	QPoint pos(widget->mapToGlobal(me->pos()));
	m_geometry = QRect(QRect(m_start, QSize(1, 1)) | QRect(pos, QSize(1, 1)));

	//TimerEvents execution is delayed until all other events have been processed.
	//In particular, we want to pick after the screen refreshes
	QTimer::singleShot(0, this, SLOT(pick()));
}

//------------------------------------------------------------------

void ScreenPicker::pick()
{
	//Someway, on MACOSX 10.7 (Lion) there may be screen refresh events pending at this point.
	//Process them before picking.
	QCoreApplication::processEvents();

	QColor color(pickScreenRGB(m_geometry));
	RGBPicker::setCurrentColorWithUndo(TPixel32(color.red(), color.green(), color.blue()));

	m_geometry = QRect();
}

//------------------------------------------------------------------

void ScreenPicker::paintEvent(QWidget *widget, QPaintEvent *pe)
{
	if (!m_mousePressed)
		return;

	QPainter painter(widget);

	QRect relativeGeom(
		widget->mapFromGlobal(m_geometry.topLeft()),
		widget->mapFromGlobal(m_geometry.bottomRight()));

	painter.setPen(QColor(0, 0, 255, 128));
	painter.setBrush(QColor(0, 0, 255, 64));
	painter.drawRect(relativeGeom);
}

//------------------------------------------------------------------

void ScreenPicker::startGrab()
{
	if (!m_mouseGrabbed) {
		m_mouseGrabbed = true;

		DVGui::ScreenBoard *screenBoard = DVGui::ScreenBoard::instance();

		screenBoard->drawings().push_back(this);
		screenBoard->grabMouse(getToolCursor(ToolCursor::PickerCursor));
		screenBoard->update();
	}
}

//***********************************************************************************
//    Pick Screen Command instantiation
//***********************************************************************************

class PickScreenCommandHandler : public MenuItemHandler
{
public:
	PickScreenCommandHandler(CommandId cmdId) : MenuItemHandler(cmdId) {}
	void execute()
	{
		static ScreenPicker *picker = new ScreenPicker;
		picker->startGrab();
	}
} pickScreenCHInstance("A_ToolOption_PickScreen");