/****************************************************************************

 Copyright (C) 2002-2014 Gilles Debunne. All rights reserved.

 This file is part of the QGLViewer library version 2.6.2.

 http://www.libqglviewer.com - contact@libqglviewer.com

 This file may be used under the terms of the GNU General Public License 
 versions 2.0 or 3.0 as published by the Free Software Foundation and
 appearing in the LICENSE file included in the packaging of this file.
 In addition, as a special exception, Gilles Debunne gives you certain 
 additional rights, described in the file GPL_EXCEPTION in this package.

 libQGLViewer uses dual licensing. Commercial/proprietary software must
 purchase a libQGLViewer Commercial License.

 This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
 WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.

*****************************************************************************/

#include "case.h"
#include <qgl.h>
#include <QGLViewer/vec.h>

using namespace qglviewer;

/////////////
// Drawing //
/////////////
static const float thickness = 0.2f;
static const float pieceSize = 0.8f;
static const float pieceShift = (1.0 - pieceSize) / 2.0;

//static qglviewer::Vec posOf(const QPoint& p) { return qglviewer::Vec(p.x()+0.5,p.y()+0.5,0.0); };

void Case::draw(const QPoint& pos) const
{
	drawBasis(pos);
	drawPieces(pos);
}

void Case::drawSquare(float size)
{
	static const float eps = 0.002f;
	glDisable(GL_LIGHTING);
	glBegin(GL_LINE_LOOP);
	glLineWidth(3);
	glVertex3f(-eps, -eps, thickness+eps);
	glVertex3f(size+eps, -eps, thickness+eps);
	glVertex3f(size+eps, size+eps, thickness+eps);
	glVertex3f(-eps, size+eps, thickness+eps);
	glEnd();
	glEnable(GL_LIGHTING);
}

void Case::drawTop(const QPoint& pos) const
{
	glEnable(GL_BLEND);
	glPushMatrix();
	glTranslatef(pos.x(), pos.y(), altitude_*thickness + 0.002f);

	glBegin(GL_QUADS);
	glColor4f(0.9f, 0.2f, 0.2f, 0.7f);
	glNormal3f(0.0, 0.0, 1.0);
	glVertex2f(0.0, 0.0);
	glVertex2f(1.0, 0.0);
	glVertex2f(1.0, 1.0);
	glVertex2f(0.0, 1.0);
	glEnd();

	glPopMatrix();
	glDisable(GL_BLEND);
}

void Case::drawTopPiece(const QPoint& pos) const
{
	glEnable(GL_BLEND);
	glPushMatrix();
	const float delta = pieceShift / 2.0f;
	glTranslatef(pos.x()+pieceShift-delta, pos.y()+pieceShift-delta, (altitude_ + nbBottom() + nbTop() - 1)*thickness);

	glColor4f(0.5, 0.5, 0.9f, 0.7f);

	Case::drawParallelepiped(pieceSize+2*delta, thickness+delta);

	glPopMatrix();
	glDisable(GL_BLEND);
}

void Case::drawTopPieceTop(const QPoint& pos) const
{
	glEnable(GL_BLEND);
	glPushMatrix();
	glTranslatef(pos.x()+pieceShift, pos.y()+pieceShift, (altitude_ + nbBottom() + nbTop())*thickness + 0.02f);

	glBegin(GL_QUADS);
	glColor4f(0.2f, 0.7f, 0.2f, 0.5f);
	glNormal3f(0.0, 0.0, 1.0);
	glVertex2f(0.0, 0.0);
	glVertex2f(pieceSize, 0.0);
	glVertex2f(pieceSize, pieceSize);
	glVertex2f(0.0, pieceSize);
	glEnd();

	glPopMatrix();
	glDisable(GL_BLEND);
}

void Case::drawPieces(const QPoint& pos) const
{
	for (int i=0; i<nbBottom(); i++)
		drawPiece(pos, i, !topIsBlack());
	for (int i=nbBottom(); i<nbBottom()+nbTop(); i++)
		drawPiece(pos, i, topIsBlack());
}

void Case::drawBasis(const QPoint& pos) const
{
	glPushMatrix();
	glTranslatef(pos.x(), pos.y(), 0.0);

	glEnable(GL_TEXTURE_2D);
	glColor3f(0.5, 0.5, 0.5);
	Case::drawParallelepiped(1.0, altitude_*thickness);
	glDisable(GL_TEXTURE_2D);

	glColor3f(0.2f, 0.2f, 0.2f);

	for (int i=0; i<altitude_; i++)
	{
		Case::drawSquare(1.0);
		glTranslatef(0.0, 0.0, thickness);
	}

	glPopMatrix();
}

void Case::drawPiece(const QPoint& pos, int altitude, bool black) const
{
	glPushMatrix();
	glTranslatef(pos.x()+pieceShift, pos.y()+pieceShift, (altitude_ + altitude)*thickness + 0.001f);

	if (black)
		glColor3f(0.2f, 0.2f, 0.2f);
	else
		glColor3f(0.6f, 0.6f, 0.6f);

	Case::drawParallelepiped(pieceSize, thickness);
	Case::drawSquare(pieceSize);

	glPopMatrix();
}

void Case::drawParallelepiped(float size, float height)
{
	glBegin(GL_QUADS);
	// Top
	glNormal3f(0.0, 0.0, 1.0);
	glTexCoord2i(0,0);
	glVertex3f(0.0, 0.0, height);
	glTexCoord2i(1,0);
	glVertex3f(size, 0.0, height);
	glTexCoord2i(1,1);
	glVertex3f(size, size, height);
	glTexCoord2i(0,1);
	glVertex3f(0.0, size, height);

	// Sides
	glNormal3f(0.0, -1.0, 0.0);
	glTexCoord2i(0,0);
	glVertex3f(0.0, 0.0, height);
	glTexCoord2i(1,0);
	glVertex3f(0.0, 0.0, 0.0);
	glTexCoord2i(1,1);
	glVertex3f(size, 0.0, 0.0);
	glTexCoord2i(0,1);
	glVertex3f(size, 0.0, height);

	glNormal3f(1.0, 0.0, 0.0);
	glTexCoord2i(0,0);
	glVertex3f(size, 0.0, height);
	glTexCoord2i(1,0);
	glVertex3f(size, 0.0, 0.0);
	glTexCoord2i(1,1);
	glVertex3f(size, size, 0.0);
	glTexCoord2i(0,1);
	glVertex3f(size, size, height);

	glNormal3f(0.0, 1.0, 0.0);
	glTexCoord2i(0,0);
	glVertex3f(size, size, height);
	glTexCoord2i(1,0);
	glVertex3f(size, size, 0.0);
	glTexCoord2i(1,1);
	glVertex3f(0.0, size, 0.0);
	glTexCoord2i(0,1);
	glVertex3f(0.0, size, height);

	glNormal3f(-1.0, 0.0, 0.0);
	glTexCoord2i(0,0);
	glVertex3f(0.0, size, height);
	glTexCoord2i(1,0);
	glVertex3f(0.0, size, 0.0);
	glTexCoord2i(1,1);
	glVertex3f(0.0, 0.0, 0.0);
	glTexCoord2i(0,1);
	glVertex3f(0.0, 0.0, height);

	glEnd();
}

///////////////////
// Displacements //
///////////////////
void Case::removePiece() 
{ 
	nbTop_--;
	if ((nbTop_==0) && (nbBottom_>0))
	{
		nbTop_ = nbBottom_;
		nbBottom_ = 0;
		topIsBlack_ = !topIsBlack_;
	}
	checkForRevolution();
}

void Case::addPiece(bool under, bool black) 
{ 
	if (under)
	{
		nbBottom_++;
		checkForRevolution();
	}
	else 
	{
		nbTop_++;
		nbTop_+=nbBottom_;
		nbBottom_=0;
		topIsBlack_=black; 
	}
}

void Case::checkForRevolution()
{
	if (nbBottom_ > nbTop_)
	{
		nbTop_+=nbBottom_;
		nbBottom_=0;
		topIsBlack_=!topIsBlack_; 
	}
}

///////////////////////////////
// Conversion from/to binary //
///////////////////////////////
void Case::initFrom(int binary) 
{
	altitude_ = binary & 7;
	topIsBlack_ = (binary >>= 3) & 1;
	nbTop_ = 0;
	nbBottom_ = 0;

	if (binary > 0) {
		while(! ( (binary>>=1) & 1) ) ++nbBottom_;
		++nbTop_;
		while( (binary>>=1) & 1) ++nbTop_;
	}
}

Case::operator int() const {
	int binary(0);
	if (nbTop_>0) {
		for (int i=0; i<nbTop_; ++i) {
			binary <<= 1;
			binary |= 1;
		}
		binary <<= nbBottom_;

		binary <<= 1;
		if (topIsBlack_) binary |= 1;

		binary <<= 3;
	}
	binary += altitude_;
	return binary;
}

std::ostream & operator<<(std::ostream& out, const Case& c) {
	return out << "[alt(" << c.altitude_
		<< "), col(" << c.topIsBlack_
		<< "), top(" << c.nbTop_
		<< "), bot(" << c.nbBottom_
		<< ")]";
}

std::istream & operator>>(std::istream& in, Case& c) {
	int binary;
	in >> binary;
	c.initFrom(binary);
	return in;
}
