#include <QMouseEvent>
#include <QPaintEvent>
#include <QPainter>

#include "toonzqt/marksbar.h"

//*****************************************************************************
//    Local namespace stuff
//*****************************************************************************

namespace
{

void crop(QVector<int> &values, int min, int max)
{
	QVector<int>::iterator it, end = values.end();
	for (it = values.begin(); it != end; ++it)
		*it = tcrop(*it, min, max);
}

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

void rollDown(QVector<int> &values, int max, int sortDist)
{
	assert(!values.empty());
	values.back() = tmin(max, values.back());

	int val;

	QVector<int>::iterator it, jt, beg = values.begin();
	for (it = values.end(), jt = --it; jt != beg; jt = it) {
		--it;
		val = *jt - sortDist;
		if (*it > val)
			*it = val;
	}
}

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

void rollUp(QVector<int> &values, int min, int sortDist)
{
	assert(!values.empty());
	values.front() = tmax(min, values.front());

	int val;

	QVector<int>::iterator it, jt, end = values.end();
	for (jt = values.begin(), it = jt++; jt != end; it = jt, ++jt) {
		val = *it + sortDist;
		if (val > *jt)
			*jt = val;
	}
}
}

//*****************************************************************************
//    MarksBar implementation
//*****************************************************************************

MarksBar::MarksBar(QWidget *parent, bool markUp)
	: QFrame(parent), m_markUp(markUp), m_min(0), m_max(100), m_sortDist(-1), m_selectedMark(-1)
{
	setMinimumWidth(100);
	setFixedHeight(6);
}

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

void MarksBar::setRange(int min, int max, int sortDist)
{
	assert(min <= max);
	m_min = min, m_max = max, m_sortDist = sortDist;

	conformValues();
	update();
}

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

int MarksBar::valToPos(int val)
{
	const QRect contsRect = contentsRect();
	return contsRect.left() + contsRect.width() * ((val - m_min) / (double)(m_max - m_min));
}

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

int MarksBar::posToVal(int pos)
{
	const QRect contsRect = contentsRect();
	return m_min + (m_max - m_min) * ((pos - contsRect.left()) / (double)contsRect.width());
}

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

void MarksBar::conformValues(bool preferRollDown)
{
	if (m_values.empty())
		return;

	if (m_sortDist < 0)
		::crop(m_values, m_min, m_max);
	else {
		if (preferRollDown) {
			::rollDown(m_values, m_max, m_sortDist);
			::rollUp(m_values, m_min, m_sortDist);
		} else {
			::rollUp(m_values, m_min, m_sortDist);
			::rollDown(m_values, m_max, m_sortDist);
		}
	}

	update();
	emit marksUpdated();
}

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

void MarksBar::mousePressEvent(QMouseEvent *me)
{
	int newDist, currDist = (std::numeric_limits<int>::max)();

	int val = posToVal(me->x());

	//Select the nearest mark. If the distance is too great, select none.
	int i, size = m_values.size();
	for (i = 0; i < size; ++i) {
		newDist = abs(m_values[i] - val);
		if (newDist < 7 && newDist < currDist)
			m_selectedMark = i;
	}

	update();
}

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

void MarksBar::mouseMoveEvent(QMouseEvent *me)
{
	if (m_selectedMark < 0)
		return;

	int newVal = tcrop(posToVal(me->x()), m_min, m_max);
	bool left = newVal < m_values[m_selectedMark];

	m_values[m_selectedMark] = newVal;
	conformValues(left);

	update();
}

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

void MarksBar::mouseReleaseEvent(QMouseEvent *me)
{
	m_selectedMark = -1;
	emit marksReleased();
}

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

void MarksBar::drawMark(QPainter &p, int pos, const QColor &color)
{
	QPolygon poly(3);
	if (m_markUp) {
		poly[0] = QPoint(pos - 5, 5);
		poly[1] = QPoint(pos + 5, 5);
		poly[2] = QPoint(pos, 0);
	} else {
		poly[0] = QPoint(pos - 5, 0);
		poly[1] = QPoint(pos + 5, 0);
		poly[2] = QPoint(pos, 5);
	}

	p.setBrush(color);
	p.drawPolygon(poly);
}

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

void MarksBar::paintEvent(QPaintEvent *pe)
{
	QPainter p(this);

	assert(m_values.size() == m_colors.size());

	//Draw markers
	int i, size = m_values.size();
	for (i = 0; i < size; ++i)
		drawMark(p, valToPos(m_values[i]), m_colors[i]);
}