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

 Copyright (C) 2002-2008 Gilles Debunne. All rights reserved.

 This file is part of the QGLViewer library version 2.3.1.

 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 "dvonnviewer.h"
#include "game.h"
#include "drawer.h"
#include <fstream>
#include <math.h>
#include <qmessagebox.h>

#if QT_VERSION >= 0x040000
# include <QMouseEvent>
#endif

using namespace std;
using namespace qglviewer;
using namespace dvonn;

namespace
{
  int debugInterval;
  const unsigned int nbAnimationSteps = 30;
  class BoardConstraint : public Constraint
  {
  public:
    virtual void constrainRotation(Quaternion& q, Frame * const fr)
      {
	const Vec up = fr->transformOf(Vec(0.0, 0.0, 1.0));
	Vec axis = q.axis();
	float angle = 2.0*acos(q[3]);
	if (fabs(axis*up) > fabs(axis.x))
	  axis.projectOnAxis(up);
	else
	{
	  angle = (axis.x > 0.0) ? angle : -angle;
	  axis.setValue(fabs(axis.x), 0.0, 0.0);
	  const float currentAngle = asin(fr->inverseTransformOf(Vec(0.0, 0.0, -1.0)).z);
	  if (currentAngle + angle > -0.2)
	    angle = -0.2 - currentAngle; // Not too low
	  if (currentAngle + angle < -M_PI/2.0)
	    angle = -M_PI/2.0 - currentAngle; // Do not pass on the other side
	}
	q = Quaternion(axis, angle);
      }
  };
}
//************************************************************
// Implementation of DvonnViewer
//************************************************************
#if QT_VERSION < 0x040000
DvonnViewer::DvonnViewer(QWidget* parent, const char* name)
  : QGLViewer(parent, name),
#else
DvonnViewer::DvonnViewer(QWidget* parent)
  : QGLViewer(parent),
#endif
    game_(NULL),
    selectionMode_(-1),
    piecePicked_(false),
    dstPicked_(Board::ConstStackHandle::null()),
    srcPicked_(Board::ConstStackHandle::null()),
    showPossDest_(true),
    showStatus_(false),
    showLabels_(false),
    useLight_(true),
    dragToPlay_(false),
    fadeGhosts_(NULL),
    animateT_(-1.0f),
    showAnimation_(true),
    scoreT_(-1.0f)
{
  drawer_ = new Drawer;
  fadeTimer_ = new QTimer();
  connect(fadeTimer_,SIGNAL(timeout()),this,SLOT(advanceFadeOut()));
  animateTimer_ = new QTimer();
  connect(animateTimer_,SIGNAL(timeout()),this,SLOT(advanceAnimateMove()));
  scoreTimer_ = new QTimer();
  connect(scoreTimer_,SIGNAL(timeout()),this,SLOT(advanceAnimateScore()));
}
DvonnViewer::~DvonnViewer()
{
  delete drawer_;
  delete fadeTimer_;
  delete animateTimer_;
  delete scoreTimer_;
}
void
DvonnViewer::advanceFadeOut()
{
  fadeAlpha_ -= 0.05f;
  if (fadeAlpha_ < 0.0f)
  {
    fadeTimer_->stop();
    fadeAlpha_ = 0.0f;
    fadeGhosts_ = NULL;
  }
  updateGL();
}
void
DvonnViewer::fadeOut(const Board::Ghosts* g)
{
  if ((fadeGhosts_ = g) != NULL && !g->empty())
  {
    fadeAlpha_ = 1.0f;
    fadeTimer_->start(30);
  }
}
void
DvonnViewer::advanceAnimateMove()
{
  animateT_ += 1.0f/nbAnimationSteps;
  if (animateT_ >= 1.0f)
  {
    animateTimer_->stop();
    animateT_ = -1.0f;
    emit requested(animateMove_);
  }
  updateGL();
}
void
DvonnViewer::animateMove(Game::Move m)
{
  if (animateT_ < 0.0f)
  {
    if (showAnimation_)
    {
      animateMove_ = m;
      animateT_ = 0.0f;
      static const float v = 1.0f/250;
      const float d = drawer_->estimateDrawMoveLength(game_->board(),m);
      const float T = d/v;
      animateTimer_->start(static_cast<int>(T/nbAnimationSteps));
    }
    else
    {
      emit requested(m);
    }
  }
}
void
DvonnViewer::advanceAnimateScore()
{
  scoreT_ += 1.0f/nbAnimationSteps;
  if (scoreT_ >= 1.0f)
  {
    scoreTimer_->stop();
    scoreT_ = -1.0f;
    emit requested(scoreMove_);
  }
  updateGL();
}
void
DvonnViewer::animateScore()
{
  if (scoreT_ < 0.0f)
  {
    // Stack will be moved to to positions at center of the board
    static const Board::Coord centers[2] =
      {
	Board::Coord(Board::nbSpacesMaxOnRow()/2,Board::nbRows()/2+1),
	Board::Coord(Board::nbSpacesMaxOnRow()/2+1,Board::nbRows()/2+1)
      };
    // Search for a stack to move
    for (Board::ConstStackIterator
	   iter = game_->board().stacks_begin(),
	   istop= game_->board().stacks_end();
	 iter != istop;++iter)
    {
      if (iter.stackCoord() != centers[0] &&
	  iter.stackCoord() != centers[1] &&
	  iter->hasPieces())
      {
	Color c = iter->onTop()->color();
	if (c != Red)
	{
	  scoreMove_ = Game::Move(iter.stackCoord(),centers[c-1]);
	  scoreT_ = 0.0f;
	  static const float v = 1.0f/250;
	  const float d = drawer_->estimateDrawMoveLength(game_->board(),
							  scoreMove_);
	  const float T = d/v;
	  scoreTimer_->start(debugInterval = static_cast<int>(T/nbAnimationSteps));
	  return;
	}
      }
    }
  }
}
void
DvonnViewer::stopAllAnimations()
{
  fadeTimer_->stop();
  fadeAlpha_ = 0.0f;
  fadeGhosts_ = NULL;

  animateTimer_->stop();
  animateT_ = -1.0f;

  scoreTimer_->stop();
  scoreT_ = -1.0f;

  updateGL();
}
void
DvonnViewer::setGame(Game* g)
{
  game_ = g;
}
void
DvonnViewer::toggleTexture(bool b)
{
  drawer_->toggleTexture(b);
  updateGL();
}
void
DvonnViewer::toggleLight(bool b)
{
  useLight_ = b;
  updateGL();
}
void
DvonnViewer::toggleShowPossible(bool b)
{
  showPossDest_ = b;
  if (showPossDest_ &&
      game_->phase() == MovePhase &&
      !srcPicked_.isNull())
  {
    possDests_ = game_->possibleDestinations(srcPicked_);
  }
  updateGL();
}
void
DvonnViewer::toggleShowStatus(bool b)
{
  showStatus_ = b;
  updateGL();
}
void
DvonnViewer::toggleShowLabels(bool b)
{
  showLabels_ = b;
  updateGL();
}
void
DvonnViewer::toggleShowAnimation(bool b)
{
  showAnimation_ = b;
  updateGL();
}
void
DvonnViewer::toggleDragToPlay(bool b)
{
  dragToPlay_ = b;
  updateGL();
}
// I n i t i a l i z a t i o n   f u n c t i o n s //
void
DvonnViewer::init()
{
  initOpenGL();
  initSpotLight();
  initViewer();

  drawer_->init();
}
void
DvonnViewer::initOpenGL()
{
  glCullFace(GL_BACK);
  glEnable(GL_BLEND);
  glBlendFunc(GL_ONE,GL_ONE_MINUS_SRC_ALPHA);
  glEnable(GL_TEXTURE_2D);
  glHint(GL_PERSPECTIVE_CORRECTION_HINT,GL_NICEST);
}
void
DvonnViewer::initSpotLight()
{
  const GLfloat light_ambient[4]  = {1.0, 1.0, 1.0, 1.0};
  const GLfloat light_specular[4] = {1.0, 1.0, 1.0, 1.0};
  const GLfloat light_diffuse[4]  = {1.0, 1.0, 1.0, 1.0};

  glLightf( GL_LIGHT1, GL_SPOT_EXPONENT,  2.0);
  glLightf( GL_LIGHT1, GL_SPOT_CUTOFF,    60.0);
  glLightf( GL_LIGHT1, GL_CONSTANT_ATTENUATION, 0.1f);
  glLightf( GL_LIGHT1, GL_LINEAR_ATTENUATION, 0.3f);
  glLightf( GL_LIGHT1, GL_QUADRATIC_ATTENUATION, 0.3f);
  glLightfv(GL_LIGHT1, GL_AMBIENT,  light_ambient);
  glLightfv(GL_LIGHT1, GL_SPECULAR, light_specular);
  glLightfv(GL_LIGHT1, GL_DIFFUSE,  light_diffuse);

  const Vec pos = drawer_->boardCenter()+drawer_->boardRadius()*drawer_->boardUpVector();
  const float posv[4] = { pos.x,pos.y,pos.z,1.0f };
  const Vec dir = -drawer_->boardUpVector();
  const float dirv[4] = { dir.x,dir.y,dir.z,1.0f };
  glLightfv(GL_LIGHT1,GL_POSITION,posv);
  glLightfv(GL_LIGHT1,GL_SPOT_DIRECTION,dirv);
}
void
DvonnViewer::initViewer()
{
  setSceneCenter(drawer_->boardCenter());
  setSceneRadius(drawer_->boardRadius());
  camera()->setUpVector(drawer_->boardUpVector());
  camera()->setPosition(drawer_->defaultEyePosition());
  camera()->lookAt(sceneCenter());
  // Limit camera rotation motion
  camera()->frame()->setConstraint(new BoardConstraint());

#if QT_VERSION >= 0x040000
# define CONTROL Qt::ControlModifier
# define SHIFT Qt::ShiftModifier
#else
# define CONTROL Qt::ControlButton
# define SHIFT Qt::ShiftButton
#endif

  // Defines new bindings
  setMouseBindingDescription(Qt::LeftButton, "Moves stack");
  setMouseBinding(CONTROL | Qt::LeftButton,CAMERA,ROTATE);
  setMouseBinding(Qt::MidButton,  ZOOM_TO_FIT,true);
  setMouseBinding(Qt::RightButton,ZOOM_TO_FIT,true);
  setMouseBinding(CONTROL | Qt::LeftButton,RAP_FROM_PIXEL,true);
  setMouseBinding(CONTROL | Qt::RightButton, RAP_IS_CENTER, true);

  // Disable most of the default bindings
  setMouseBinding(CONTROL | Qt::MidButton  ,CAMERA,NO_MOUSE_ACTION);
  setMouseBinding(CONTROL | Qt::RightButton,CAMERA,NO_MOUSE_ACTION);
  setMouseBinding(Qt::LeftButton,NO_CLICK_ACTION);
  setMouseBinding(Qt::LeftButton,NO_CLICK_ACTION,true);
  setMouseBinding(CONTROL | Qt::LeftButton  | Qt::MidButton,NO_CLICK_ACTION);
  setMouseBinding(CONTROL | Qt::RightButton | Qt::MidButton,NO_CLICK_ACTION);
  setMouseBinding(Qt::LeftButton  | Qt::MidButton, NO_CLICK_ACTION);
  setMouseBinding(Qt::RightButton | Qt::MidButton, NO_CLICK_ACTION);
  setMouseBinding(SHIFT | Qt::LeftButton,NO_CLICK_ACTION);

  setMouseBinding(Qt::RightButton,NO_CLICK_ACTION, true, Qt::MidButton);
  setMouseBinding(Qt::LeftButton, NO_CLICK_ACTION, true, Qt::MidButton);
  setMouseBinding(Qt::RightButton,NO_CLICK_ACTION, true, Qt::LeftButton);
  setMouseBinding(Qt::LeftButton, NO_CLICK_ACTION, true, Qt::RightButton);

  setWheelBinding(CONTROL, FRAME,NO_MOUSE_ACTION);
}
void
DvonnViewer::draw()
{
  (useLight_?glEnable:glDisable)(GL_LIGHTING);
  glEnable(GL_LIGHT1);

  drawAllSpaces();
  drawer_->drawComplement(showLabels_);
  drawAllPieces();
  Player p = game_->theOnePlaying();
  Color c = game_->phase() == RedPlacementPhase?Red:colorOf(p);
  drawer_->drawWhitePiecePools(game_->board(),
			       p==WhitePlayer && piecePicked_);
  drawer_->drawBlackPiecePools(game_->board(),
			       p==BlackPlayer && piecePicked_);
  if (piecePicked_ && !dstPicked_.isNull())
  {
    drawer_->drawTransparentPiece(c,dstPicked_);
  }
  if (!piecePicked_ && !srcPicked_.isNull())
  {
    drawer_->drawTransparentPieces(srcPicked_->begin(),srcPicked_->end(),
				   srcPicked_.stackCoord(),0.0f,0.4f);
    if (showPossDest_)
    {
      glColor3f(1.0f,1.0f,0.0f);
      for (deque<Board::ConstStackHandle>::const_iterator
	     iter = possDests_.begin();
	   iter != possDests_.end();++iter)
      {
	drawer_->highlightPieces(*iter);
      }
    }
    if (!dstPicked_.isNull())
    {
      drawer_->drawTransparentPieces(srcPicked_->begin(),srcPicked_->end(),
				     dstPicked_.stackCoord(),
				     dstPicked_->height(),
				     0.9f);
    }
  }
  // Ghosts
  if (fadeGhosts_)
  {
    for (Board::Ghosts::const_iterator
	   iter = fadeGhosts_->begin();
	 iter != fadeGhosts_->end();++iter)
    {
      drawer_->drawTransparentPieces(iter->stack.begin(),
				     iter->stack.end(),
				     iter->coord,
				     0.0f,
				     fadeAlpha_*fadeAlpha_);
    }
  }
  // Animated move
  if (animateT_>=0.0f)
  {
    drawer_->drawMove(game_->board(),animateMove_,animateT_);
  }
  if (scoreT_>=0.0f)
  {
    drawer_->drawMove(game_->board(),scoreMove_,scoreT_);
  }
}
void
DvonnViewer::drawAllPieces(bool pick)
{
  unsigned int name=0;
  for (Board::ConstStackIterator
	 iter = game_->board().stacks_begin(),
	 istop= game_->board().stacks_end();
       iter != istop;++iter)
  {
    if (pick) glPushName(name++);
    if (srcPicked_ != iter &&
	(animateT_ < 0.0f || iter.stackCoord() != animateMove_.src) &&
	(scoreT_ < 0.0f || iter.stackCoord() != scoreMove_.src))
    {
      drawer_->drawPieces(iter);
    }
    if (pick) glPopName();
  }
  if (showStatus_ && !pick)
  {
    glPushAttrib(GL_ALL_ATTRIB_BITS);
    glDisable(GL_LIGHTING);
    glColor3f(0.0,1.0,0.0f);
    for (Board::ConstStackIterator
	   iter = game_->board().stacks_begin(),
	   istop= game_->board().stacks_end();
	 iter != istop;++iter)
    {
      drawer_->drawStatus(iter,this);
    }
  }
  glPopAttrib();
}
void
DvonnViewer::drawAllSpaces(bool pick)
{
  unsigned int name=0;
  for (Board::ConstStackIterator
	 iter = game_->board().stacks_begin(),
	 istop= game_->board().stacks_end();
       iter != istop;++iter)
  {
    if (pick) glPushName(name++);
    drawer_->draw(iter);
    if (pick) glPopName();
  }
}
void
DvonnViewer::drawWithNames()
{
  if (game_->isOver()) return;
  switch (selectionMode_)
  {
  case 1:
    glPushName(0);
    if (game_->theOnePlaying() == WhitePlayer)
    {
      drawer_->drawWhitePiecePools(game_->board(),false);
    }
    else
    {
      drawer_->drawBlackPiecePools(game_->board(),false);
    }
    glPopName();
    break;
  case 2:
  case 5:
    drawAllSpaces(true);
    break;
  case 3:
  case 4:
    drawAllPieces(true);
    break;
  default:
    cout<<"No selection mode active!"<<endl;
  }
}
void
DvonnViewer::postSelection(const QPoint&)
{
  switch (selectionMode_)
  {
  case 1:
    piecePicked_ = (selectedName() != -1);
    break;
  case 2:
    if (selectedName() != -1)
    {
      Board::ConstStackIterator iter = game_->board().stacks_begin();
      for (int i=0;i<selectedName();++i) ++iter;
      dstPicked_ = iter;
      if (dstPicked_->hasPieces())
	dstPicked_ = Board::ConstStackHandle::null();
    }
    else
    {
      dstPicked_ = Board::ConstStackHandle::null();
    }
    break;
  case 3:
    if (selectedName() != -1)
    {
      Board::ConstStackIterator iter = game_->board().stacks_begin();
      for (int i=0;i<selectedName();++i) ++iter;
      srcPicked_ = iter;
      if (!srcPicked_.isNull() &&
	  srcPicked_->onTop()->color() !=
	  colorOf(game_->theOnePlaying()))
      {
	srcPicked_ = Board::ConstStackHandle::null();
      }
    }
    else
    {
      srcPicked_ = Board::ConstStackHandle::null();
    }
    break;
  case 4:
  case 5:
    if (selectedName() != -1)
    {
      Board::ConstStackIterator iter = game_->board().stacks_begin();
      for (int i=0;i<selectedName();++i) ++iter;
      dstPicked_ = iter;
      if (dstPicked_ == srcPicked_)
      {
	dstPicked_ = Board::ConstStackHandle::null();
      }
      if (!dstPicked_.isNull() &&
	  !game_->isLegalMove(Game::Move(srcPicked_.stackCoord(),
					 dstPicked_.stackCoord())))
      {
	dstPicked_ = Board::ConstStackHandle::null();
      }
    }
    else
    {
      dstPicked_ = Board::ConstStackHandle::null();
    }
    break;
  };
  selectionMode_ = -1;
}
void
DvonnViewer::mousePressEvent(QMouseEvent* e)
{
#if QT_VERSION >= 0x040000
  if (e->button() == Qt::LeftButton)
#else
  if (e->stateAfter() == Qt::LeftButton)
#endif
    {
    if (game_->phase() == RedPlacementPhase ||
	game_->phase() == PiecePlacementPhase)
    {
      if (dragToPlay_)
      {
	selectionMode_ = 1;
	select(e);
	if (!dstPicked_.isNull())
	{
	  piecePicked_ = true;
	}
      }
      else
      {
	piecePicked_ = true;;
	Board::ConstStackHandle firstClickDstPicked = dstPicked_;
	selectionMode_ = 2;
	select(e);
	if (dstPicked_ == firstClickDstPicked)
	{
	  commitDstPicked();
	}
	else if (dstPicked_.isNull())
	{
	  piecePicked_ = false;
	}
      }
      updateGL();
    }
    else // phase == MovePhase
    {
      if (dragToPlay_ ||
	  (!dragToPlay_ && srcPicked_.isNull()))
      {
	selectionMode_ = 3;
	select(e);
	// Check that the picked src is free
	if (!srcPicked_.isNull() &&
	    !game_->board().isFree(srcPicked_))
	{
	  srcPicked_ = Board::ConstStackHandle::null();
	}
	// If asked, search for possible destinations
	if (showPossDest_ && !srcPicked_.isNull())
	{
	  possDests_ = game_->possibleDestinations(srcPicked_);
	}
	setMouseTracking(true);
      }
      else
      {
	selectionMode_ = 4;
	select(e);
	// Since selection in mode 4 can work only for case with pieces, we
	// try to select a case if no case is selected yet.
	if (dstPicked_.isNull())
	{
	  selectionMode_ = 5;
	  select(e);
	}
	commitDstPicked();
      }
      updateGL();
    }
  }
  else QGLViewer::mousePressEvent(e);
}
void
DvonnViewer::mouseMoveEvent(QMouseEvent* e)
{
#if QT_VERSION >= 0x040000
  if ((dragToPlay_ && e->button() == Qt::LeftButton) ||
#else
  if ((dragToPlay_ && e->stateAfter() == Qt::LeftButton) ||
#endif
      (!dragToPlay_ && !srcPicked_ .isNull()) &&
      !camera()->frame()->isManipulated())
  {
    if (game_->phase() == RedPlacementPhase ||
	game_->phase() == PiecePlacementPhase)
    {
      if (piecePicked_)
      {
	selectionMode_ = 2;
	select(e);
	updateGL();
      }
    }
    else // phase == MovePhase
    {
      if (!srcPicked_.isNull())
      {
	selectionMode_ = 4;
	select(e);
	// Since selection in mode 4 can work only for case with pieces, we
	// try to select a case if no case is selected yet.
	if (dstPicked_.isNull())
	{
	  selectionMode_ = 5;
	  select(e);
	}
	updateGL();
      }
    }
  }
  else QGLViewer::mouseMoveEvent(e);
}
void
DvonnViewer::mouseReleaseEvent(QMouseEvent* e)
{
#if QT_VERSION >= 0x040000
  if (e->button() == Qt::LeftButton)
#else
  if (e->state() == Qt::LeftButton)
#endif
  {
    if (dragToPlay_)
    {
      commitDstPicked();
    }
  }
  else QGLViewer::mouseReleaseEvent(e);
}
void
DvonnViewer::commitDstPicked()
{
  if (game_->phase() == RedPlacementPhase ||
      game_->phase() == PiecePlacementPhase)
  {
    if (piecePicked_ && !dstPicked_.isNull())
    {
      Player p = game_->theOnePlaying();
      emit requested(Game::Placement(game_->phase() == RedPlacementPhase?Red:colorOf(p),
		     dstPicked_.stackCoord()));
      updateGL();
    }
  }
  else // phase == MovePhase
  {
    if (!srcPicked_.isNull() && !dstPicked_.isNull())
    {
      emit requested(Game::Move(srcPicked_.stackCoord(),
				dstPicked_.stackCoord()));
    }
  }
  piecePicked_ = false;
  dstPicked_ = Board::ConstStackHandle::null();
  srcPicked_ = Board::ConstStackHandle::null();
  setMouseTracking(false);

  updateGL();
}
void
DvonnViewer::keyPressEvent(QKeyEvent* e)
{
  if (e->key() == Qt::Key_D && scoreT_ > 0.0f)
  {
    if (scoreTimer_->isActive())
      scoreTimer_->stop();
    else
      scoreTimer_->start(debugInterval);
  }
  else if (e->key() == Qt::Key_T)
  {
    toggleShowStatus(!showStatus_);
  }
  else
  QGLViewer::keyPressEvent(e);
}
QString
DvonnViewer::helpString() const
{
  QString text("<h2>D v o n n</h2>");
  text += "See the <i>Help/Rules of Dvonn</i> menu for the rules of the game.<br><br>";
  text += "Use the mouse left button to play. Middle and right buttons move camera.";
  text += "Use <b>Ctrl+left</b> to rotate the camera. See the mouse tab for complete mouse bindings.";
  return text;
}