#include "ScreenSetupView.h"
#include "ScreenSetupModel.h"
#include "ScreenSettingsDialog.h"

#include <QtCore>
#include <QtGui>

ScreenSetupView::ScreenSetupView(QWidget* parent) :
	QTableView(parent)
{
	setDropIndicatorShown(true);
	setDragDropMode(DragDrop);
	setSelectionMode(SingleSelection);

	setHorizontalScrollBarPolicy(Qt::ScrollBarAlwaysOff);
	setVerticalScrollBarPolicy(Qt::ScrollBarAlwaysOff);

	setIconSize(QSize(64, 64));
	horizontalHeader()->hide();
	verticalHeader()->hide();
}

void ScreenSetupView::setModel(ScreenSetupModel* model)
{
	QTableView::setModel(model);
	setTableSize();
}

ScreenSetupModel* ScreenSetupView::model() const
{
	return qobject_cast<ScreenSetupModel*>(QTableView::model());
}

void ScreenSetupView::setTableSize()
{
	for (int i = 0; i < model()->columnCount(); i++)
		setColumnWidth(i, width() / model()->columnCount());

	for (int i = 0; i < model()->rowCount(); i++)
		setRowHeight(i, height() / model()->rowCount());
}

void ScreenSetupView::resizeEvent(QResizeEvent* event)
{
	setTableSize();
	event->ignore();
}

void ScreenSetupView::mouseDoubleClickEvent(QMouseEvent* event)
{
	if (event->buttons() & Qt::LeftButton)
	{
		int col = columnAt(event->pos().x());
		int row = rowAt(event->pos().y());

		if (!model()->screen(col, row).isNull())
		{
			ScreenSettingsDialog dlg(this, &model()->screen(col, row));
			dlg.exec();
		}
	}
	else
		event->ignore();
}

void ScreenSetupView::dragEnterEvent(QDragEnterEvent* event)
{
	// we accept anything that enters us by a drag as long as the
	// mime type is okay. anything else is dealt with in dragMoveEvent()
	if (event->mimeData()->hasFormat(ScreenSetupModel::mimeType()))
		event->accept();
	else
		event->ignore();
}

void ScreenSetupView::dragMoveEvent(QDragMoveEvent* event)
{
	if (event->mimeData()->hasFormat(ScreenSetupModel::mimeType()))
	{
		// where does the event come from? myself or someone else?
		if (event->source() == this)
		{
			// myself is ok, but then it must be a move action, never a copy
			event->setDropAction(Qt::MoveAction);
			event->accept();
		}
		else
		{
			int col = columnAt(event->pos().x());
			int row = rowAt(event->pos().y());

			// a drop from outside is not allowed if there's a screen already there.
			if (!model()->screen(col, row).isNull())
				event->ignore();
			else
				event->acceptProposedAction();
		}
	}
	else
		event->ignore();
}

// this is reimplemented from QAbstractItemView::startDrag()
void ScreenSetupView::startDrag(Qt::DropActions)
{
	QModelIndexList indexes = selectedIndexes();

	if (indexes.count() != 1)
		return;

	QMimeData* pData = model()->mimeData(indexes);
	if (pData == NULL)
		return;

	QPixmap pixmap = *model()->screen(indexes[0]).pixmap();
	QDrag* pDrag = new QDrag(this);
	pDrag->setPixmap(pixmap);
	pDrag->setMimeData(pData);
	pDrag->setHotSpot(QPoint(pixmap.width() / 2, pixmap.height() / 2));

	if (pDrag->exec(Qt::MoveAction, Qt::MoveAction) == Qt::MoveAction)
	{
		selectionModel()->clear();

		// make sure to only delete the drag source if screens weren't swapped
		// see ScreenSetupModel::dropMimeData
		if (!model()->screen(indexes[0]).swapped())
			model()->screen(indexes[0]) = Screen();
		else
			model()->screen(indexes[0]).setSwapped(false);
	}
}

QStyleOptionViewItem ScreenSetupView::viewOptions() const
{
	QStyleOptionViewItem option = QTableView::viewOptions();
	option.showDecorationSelected = true;
	option.decorationPosition = QStyleOptionViewItem::Top;
	option.displayAlignment = Qt::AlignCenter;
	option.textElideMode = Qt::ElideMiddle;
	return option;
}