// SPDX-License-Identifier: GPL-2.0
#include "profile-widget/ruleritem.h"
#include "profile-widget/profilewidget2.h"
#include "core/settings/qPrefTechnicalDetails.h"

#include <qgraphicssceneevent.h>

#include "core/profile.h"

RulerNodeItem2::RulerNodeItem2() :
	pInfo(NULL),
	idx(-1),
	ruler(NULL),
	timeAxis(NULL),
	depthAxis(NULL)
{
	setRect(-8, -8, 16, 16);
	setBrush(QColor(0xff, 0, 0, 127));
	setPen(QColor(Qt::red));
	setFlag(ItemIsMovable);
	setFlag(ItemSendsGeometryChanges);
	setFlag(ItemIgnoresTransformations);
}

void RulerNodeItem2::setPlotInfo(const plot_info &info)
{
	pInfo = &info;
	idx = 0;
}

void RulerNodeItem2::setRuler(RulerItem2 *r)
{
	ruler = r;
}

void RulerNodeItem2::recalculate()
{
	if (!pInfo || pInfo->nr <= 0)
		return;

	const struct plot_data &last = pInfo->entry[pInfo->nr - 1];
	if (x() < 0) {
		setPos(0, y());
	} else if (x() > timeAxis->posAtValue(last.sec)) {
		setPos(timeAxis->posAtValue(last.sec), depthAxis->posAtValue(last.depth));
	} else {
		idx = 0;
		while (idx < pInfo->nr && timeAxis->posAtValue(pInfo->entry[idx].sec) < x())
			++idx;
		const struct plot_data &data = pInfo->entry[idx];
		setPos(timeAxis->posAtValue(data.sec), depthAxis->posAtValue(data.depth));
	}
}

void RulerNodeItem2::mouseMoveEvent(QGraphicsSceneMouseEvent *event)
{
	qreal x = event->scenePos().x();
	if (x < 0.0)
		x = 0.0;
	setPos(x, event->scenePos().y());
	recalculate();
	ruler->recalculate();
}

RulerItem2::RulerItem2() : pInfo(NULL),
	source(new RulerNodeItem2()),
	dest(new RulerNodeItem2()),
	timeAxis(NULL),
	depthAxis(NULL),
	textItemBack(new QGraphicsRectItem(this)),
	textItem(new QGraphicsSimpleTextItem(this))
{
	source->setRuler(this);
	dest->setRuler(this);
	textItem->setFlag(QGraphicsItem::ItemIgnoresTransformations);
	textItemBack->setBrush(QColor(0xff, 0xff, 0xff, 190));
	textItemBack->setPen(QColor(Qt::white));
	textItemBack->setFlag(QGraphicsItem::ItemIgnoresTransformations);
	setPen(QPen(QColor(Qt::black), 0.0));
#ifndef SUBSURFACE_MOBILE
	connect(qPrefTechnicalDetails::instance(), &qPrefTechnicalDetails::rulergraphChanged, this, &RulerItem2::settingsChanged);
#endif
}

void RulerItem2::settingsChanged(bool value)
{
	ProfileWidget2 *profWidget = NULL;
	if (scene() && scene()->views().count())
		profWidget = qobject_cast<ProfileWidget2 *>(scene()->views().first());

	setVisible( (profWidget && profWidget->currentState == ProfileWidget2::PROFILE) ? value : false);
}

void RulerItem2::recalculate()
{
	QPointF tmp;
	QFont font;
	QFontMetrics fm(font);

	if (timeAxis == NULL || depthAxis == NULL || !pInfo || pInfo->nr == 0)
		return;

	prepareGeometryChange();
	startPoint = mapFromItem(source, 0, 0);
	endPoint = mapFromItem(dest, 0, 0);

	if (startPoint.x() > endPoint.x()) {
		tmp = endPoint;
		endPoint = startPoint;
		startPoint = tmp;
	}
	QLineF line(startPoint, endPoint);
	setLine(line);

	QString text;
	for (const std::string &s: compare_samples(dive, pInfo, source->idx, dest->idx, 1)) {
		if (!text.isEmpty())
			text += '\n';
		text += QString::fromStdString(s);
	}

	// draw text
	QGraphicsView *view = scene()->views().first();
	QPoint begin = view->mapFromScene(mapToScene(startPoint));
	textItem->setText(text);
	qreal tgtX = startPoint.x();
	const qreal diff = begin.x() + textItem->boundingRect().width();
	// clamp so that the text doesn't go out of the screen to the right
	if (diff > view->width()) {
		begin.setX(lrint(begin.x() - (diff - view->width())));
		tgtX = mapFromScene(view->mapToScene(begin)).x();
	}
	// always show the text bellow the lowest of the start and end points
	qreal tgtY = (startPoint.y() >= endPoint.y()) ? startPoint.y() : endPoint.y();
	// this isn't exactly optimal, since we want to scale the 1.0, 4.0 distances as well
	textItem->setPos(tgtX - 1.0, tgtY + 4.0);

	// setup the text background
	textItemBack->setVisible(startPoint.x() != endPoint.x());
	textItemBack->setPos(textItem->x(), textItem->y());
	textItemBack->setRect(0, 0, textItem->boundingRect().width(), textItem->boundingRect().height());
}

RulerNodeItem2 *RulerItem2::sourceNode() const
{
	return source;
}

RulerNodeItem2 *RulerItem2::destNode() const
{
	return dest;
}

void RulerItem2::setPlotInfo(const struct dive *d, const plot_info &info)
{
	dive = d;
	pInfo = &info;
	dest->setPlotInfo(info);
	source->setPlotInfo(info);
	dest->recalculate();
	source->recalculate();
	recalculate();
}

void RulerItem2::setAxis(DiveCartesianAxis *time, DiveCartesianAxis *depth)
{
	timeAxis = time;
	depthAxis = depth;
	dest->depthAxis = depth;
	dest->timeAxis = time;
	source->depthAxis = depth;
	source->timeAxis = time;
	recalculate();
}

void RulerItem2::setVisible(bool visible)
{
	QGraphicsLineItem::setVisible(visible);
	source->setVisible(visible);
	dest->setVisible(visible);
}