/*

  PictureFlow - animated image show widget

  http://pictureflow.googlecode.com

  Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies). 

  Copyright (C) 2008 Ariya Hidayat (ariya@kde.org)

  Copyright (C) 2007 Ariya Hidayat (ariya@kde.org)

  Permission is hereby granted, free of charge, to any person obtaining a copy

  of this software and associated documentation files (the "Software"), to deal

  in the Software without restriction, including without limitation the rights

  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell

  copies of the Software, and to permit persons to whom the Software is

  furnished to do so, subject to the following conditions:

  The above copyright notice and this permission notice shall be included in

  all copies or substantial portions of the Software.

  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR

  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,

  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE

  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER

  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,

  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN

  THE SOFTWARE.

*/

#include "PictureFlow.h"

// detect Qt version

#if QT_VERSION >= 0x040000

#define PICTUREFLOW_QT4

#elif QT_VERSION >= 0x030000

#define PICTUREFLOW_QT3

#elif QT_VERSION >= 235

#define PICTUREFLOW_QT2

#else

#error PictureFlow widgets need Qt 2, Qt 3 or Qt 4

#endif

#include <QGraphicsSceneResizeEvent>

#include <QGraphicsSceneMouseEvent>

#include <QGraphicsSceneMoveEvent>

#ifdef PICTUREFLOW_QT4

#include <QApplication>

#include <QCache>

#include <QHash>

#include <QImage>

#include <QKeyEvent>

#include <QPainter>

#include <QPixmap>

#include <QTimer>

#include <QVector>

#include <QWidget>

#endif

#include <QDebug>

#ifdef PICTUREFLOW_QT3

#include <qapplication.h>

#include <qcache.h>

#include <qimage.h>

#include <qpainter.h>

#include <qpixmap.h>

#include <qdatetime.h>

#include <qtimer.h>

#include <qvaluevector.h>

#include <qwidget.h>

#define qMax(x,y) ((x) > (y)) ? (x) : (y)

#define qMin(x,y) ((x) < (y)) ? (x) : (y)

#define QVector QValueVector

#define toImage convertToImage

#define contains find

#define modifiers state

#define ControlModifier ControlButton

#endif

#ifdef PICTUREFLOW_QT2

#include <qapplication.h>

#include <qarray.h>

#include <qcache.h>

#include <qimage.h>

#include <qintdict.h>

#include <qpainter.h>

#include <qpixmap.h>

#include <qdatetime.h>

#include <qtimer.h>

#include <qwidget.h>

#define qMax(x,y) ((x) > (y)) ? (x) : (y)

#define qMin(x,y) ((x) < (y)) ? (x) : (y)

#define QVector QArray

#define toImage convertToImage

#define contains find

#define modifiers state

#define ControlModifier ControlButton

#define flush flushX

#endif

// for fixed-point arithmetic, we need minimum 32-bit long

// long long (64-bit) might be useful for multiplication and division

typedef long PFreal;

#define PFREAL_SHIFT 10

#define PFREAL_ONE (1 << PFREAL_SHIFT)

#define IANGLE_MAX 1024

#define IANGLE_MASK 1023

namespace WRT {

const int slideRatio1 = 2;

const int slideRatio2 = 5;

const int KScrollTimeout = 250;

inline PFreal fmul(PFreal a, PFreal b)

{

  return ((long long)(a))*((long long)(b)) >> PFREAL_SHIFT;

}

inline PFreal fdiv(PFreal num, PFreal den)

{

  long long p = (long long)(num) << (PFREAL_SHIFT*2);

  long long q = p / (long long)den;

  long long r = q >> PFREAL_SHIFT;

  return r;

}

inline PFreal fsin(int iangle)

{

  // warning: regenerate the table if IANGLE_MAX and PFREAL_SHIFT are changed!

  static const PFreal tab[] = {

     3,    103,    202,    300,    394,    485,    571,    652,

   726,    793,    853,    904,    947,    980,   1004,   1019,

  1023,   1018,   1003,    978,    944,    901,    849,    789,

   721,    647,    566,    479,    388,    294,    196,     97,

    -4,   -104,   -203,   -301,   -395,   -486,   -572,   -653,

  -727,   -794,   -854,   -905,   -948,   -981,  -1005,  -1020,

 -1024,  -1019,  -1004,   -979,   -945,   -902,   -850,   -790,

  -722,   -648,   -567,   -480,   -389,   -295,   -197,    -98,

  3

  };

  while(iangle < 0)

    iangle += IANGLE_MAX;

  iangle &= IANGLE_MASK;

  int i = (iangle >> 4);

  PFreal p = tab[i];

  PFreal q = tab[(i+1)];

  PFreal g = (q - p);

  return p + g * (iangle-i*16)/16;

}

inline PFreal fcos(int iangle)

{

  return fsin(iangle + (IANGLE_MAX >> 2));

}

/* ----------------------------------------------------------

PictureFlowState stores the state of all slides, i.e. all the necessary

information to be able to render them.

PictureFlowAnimator is responsible to move the slides during the

transition between slides, to achieve the effect similar to Cover Flow,

by changing the state.

PictureFlowSoftwareRenderer (or PictureFlowOpenGLRenderer) is

the actual 3-d renderer. It should render all slides given the state

(an instance of PictureFlowState).

Instances of all the above three classes are stored in

PictureFlowPrivate.

------------------------------------------------------- */

struct SlideInfo

{

  int slideIndex;

  int angle;

  PFreal cx;

  PFreal cy;

  int blend;

};

class PictureFlowState

{

public:

  PictureFlowState();

  ~PictureFlowState();

  void reposition();

  void reset();

  QRgb backgroundColor;

  int slideWidth;

  int slideHeight;

  ReflectionEffect reflectionEffect;

  QVector<QImage*> slideImages;

  int angle;

  int spacing;

  PFreal offsetX;

  PFreal offsetY;

  SlideInfo centerSlide;

  QVector<SlideInfo> leftSlides;

  QVector<SlideInfo> rightSlides;

  int centerIndex;

};

class PictureFlowAnimator

{

public:

  PictureFlowAnimator();

  PictureFlowState* state;

  void start(int slide);

  void stop(int slide);

  void update();

  int target;

  int step;

  int frame;

  QTimer animateTimer;

};

class PictureFlowAbstractRenderer

{

public:

  PictureFlowAbstractRenderer(): state(0), dirty(false), widget(0), gWidget(0), gPainter(0) {}

  virtual ~PictureFlowAbstractRenderer() {}

  PictureFlowState* state;

  bool dirty;

  QWidget* widget;

  QGraphicsWidget* gWidget;

  QPainter* gPainter;

  QRect cRect; // central rect

  virtual void init() = 0;

  virtual void paint() = 0;

};

class PictureFlowSoftwareRenderer: public PictureFlowAbstractRenderer

{

public:

  PictureFlowSoftwareRenderer();

  ~PictureFlowSoftwareRenderer();

  virtual void init();

  virtual void paint();

  QRect renderSlide(const SlideInfo &slide, int col1 = -1, int col2 = -1);

private:

  QSize size;

  QRgb bgcolor;

  int effect;

  QImage buffer;

  QVector<PFreal> rays;

  QImage* blankSurface;

#ifdef PICTUREFLOW_QT4

  QCache<int,QImage> surfaceCache;

  QHash<int,QImage*> imageHash;

#endif

#ifdef PICTUREFLOW_QT3

  QCache<QImage> surfaceCache;

  QMap<int,QImage*> imageHash;

#endif

#ifdef PICTUREFLOW_QT2

  QCache<QImage> surfaceCache;

  QIntDict<QImage> imageHash;

#endif

  void render();

  void renderSlides();

  QImage* surface(int slideIndex);

};

// ------------- PictureFlowState ---------------------------------------

PictureFlowState::PictureFlowState():

backgroundColor(0), slideWidth(150), slideHeight(200),

reflectionEffect(BlurredReflection), centerIndex(0)

{

}

PictureFlowState::~PictureFlowState()

{

  for(int i = 0; i < (int)slideImages.count(); i++)

    delete slideImages[i];

}

// readjust the settings, call this when slide dimension is changed

void PictureFlowState::reposition()

{

  angle = 60*IANGLE_MAX / 360;

  offsetX = slideWidth/2 * (PFREAL_ONE-fcos(angle));

  offsetY = slideWidth/2 * fsin(angle);

  offsetX += slideWidth * PFREAL_ONE;

  offsetY += slideWidth * PFREAL_ONE / 4;

  spacing = 20;

}

// adjust slides so that they are in "steady state" position

void PictureFlowState::reset()

{

  centerSlide.angle = 0;

  centerSlide.cx = 0;

  centerSlide.cy = 0;

  centerSlide.slideIndex = centerIndex;

  centerSlide.blend = 256;

  leftSlides.resize(6);

  for(int i = 0; i < (int)leftSlides.count(); i++)

  {

    SlideInfo& si = leftSlides[i];

    si.angle = angle;

    si.cx = -(offsetX + spacing*i*PFREAL_ONE);

    si.cy = offsetY;

    si.slideIndex = centerIndex-1-i;

    si.blend = 256;

    if(i == (int)leftSlides.count()-2)

      si.blend = 128;

    if(i == (int)leftSlides.count()-1)

      si.blend = 0;

  }

  rightSlides.resize(6);

  for(int i = 0; i < (int)rightSlides.count(); i++)

  {

    SlideInfo& si = rightSlides[i];

    si.angle = -angle;

    si.cx = offsetX + spacing*i*PFREAL_ONE;

    si.cy = offsetY;

    si.slideIndex = centerIndex+1+i;

    si.blend = 256;

    if(i == (int)rightSlides.count()-2)

      si.blend = 128;

    if(i == (int)rightSlides.count()-1)

      si.blend = 0;

  }

}

// ------------- PictureFlowAnimator  ---------------------------------------

PictureFlowAnimator::PictureFlowAnimator():

state(0), target(0), step(0), frame(0)

{

}

void PictureFlowAnimator::start(int slide)

{

  target = slide;

  if(!animateTimer.isActive() && state)

  {

    step = (target < state->centerSlide.slideIndex) ? -1 : 1;

    animateTimer.start(30);

  }

}

void PictureFlowAnimator::stop(int slide)

{

  step = 0;

  target = slide;

  frame = slide << 16;

  animateTimer.stop();

}

void PictureFlowAnimator::update()

{

  if(!animateTimer.isActive())

    return;

  if(step == 0)

    return;

  if(!state)

    return;

  int speed = 16384/4;

#if 1

  // deaccelerate when approaching the target

  // we disabled clicking until the animation is done so this has to be fast enough to not annoy users

  const int max = 65536 + 16384; // was 65536*2 but that was too slow when we disabled clicks

  int fi = frame;

  fi -= (target << 16);

  if(fi < 0)

    fi = -fi;

  fi = qMin(fi, max);

  int ia = IANGLE_MAX * (fi-max/2) / (max*2);

  speed = 512 + 16384 * (PFREAL_ONE+fsin(ia))/PFREAL_ONE;

#endif

  frame += speed*step;

  int index = frame >> 16;

  int pos = frame & 0xffff;

  int neg = 65536 - pos;

  int tick = (step < 0) ? neg : pos;

  PFreal ftick = (tick * PFREAL_ONE) >> 16;

  if(step < 0)

    index++;

  if(state->centerIndex != index)

  {

    state->centerIndex = index;

    frame = index << 16;

    state->centerSlide.slideIndex = state->centerIndex;

    for(int i = 0; i < (int)state->leftSlides.count(); i++)

      state->leftSlides[i].slideIndex = state->centerIndex-1-i;

    for(int i = 0; i < (int)state->rightSlides.count(); i++)

      state->rightSlides[i].slideIndex = state->centerIndex+1+i;

  }

  state->centerSlide.angle = (step * tick * state->angle) >> 16;

  state->centerSlide.cx = -step * fmul(state->offsetX, ftick);

  state->centerSlide.cy = fmul(state->offsetY, ftick);

  if(state->centerIndex == target)

  {

    stop(target);

    state->reset();

    return;

  }

  for(int i = 0; i < (int)state->leftSlides.count(); i++)

  {

    SlideInfo& si = state->leftSlides[i];

    si.angle = state->angle;

    si.cx = -(state->offsetX + state->spacing*i*PFREAL_ONE + step*state->spacing*ftick);

    si.cy = state->offsetY;

  }

  for(int i = 0; i < (int)state->rightSlides.count(); i++)

  {

    SlideInfo& si = state->rightSlides[i];

    si.angle = -state->angle;

    si.cx = state->offsetX + state->spacing*i*PFREAL_ONE - step*state->spacing*ftick;

    si.cy = state->offsetY;

  }

  if(step > 0)

  {

    PFreal ftick = (neg * PFREAL_ONE) >> 16;

    state->rightSlides[0].angle = -(neg * state->angle) >> 16;

    state->rightSlides[0].cx = fmul(state->offsetX, ftick);

    state->rightSlides[0].cy = fmul(state->offsetY, ftick);

  }

  else

  {

    PFreal ftick = (pos * PFREAL_ONE) >> 16;

    state->leftSlides[0].angle = (pos * state->angle) >> 16;

    state->leftSlides[0].cx = -fmul(state->offsetX, ftick);

    state->leftSlides[0].cy = fmul(state->offsetY, ftick);

  }

  // must change direction ?

  if(target < index) if(step > 0)

    step = -1;

  if(target > index) if(step < 0)

    step = 1;

  // the first and last slide must fade in/fade out

  int nleft = state->leftSlides.count();

  int nright = state->rightSlides.count();

  int fade = pos / 256;

  for(int index = 0; index < nleft; index++)

  {

    int blend = 256;

    if(index == nleft-1)

      blend = (step > 0) ? 0 : 128-fade/2;

    if(index == nleft-2)

      blend = (step > 0) ? 128-fade/2 : 256-fade/2;

    if(index == nleft-3)

      blend = (step > 0) ? 256-fade/2 : 256;

    state->leftSlides[index].blend = blend;

  }

  for(int index = 0; index < nright; index++)

  {

    int blend = (index < nright-2) ? 256 : 128;

    if(index == nright-1)

      blend = (step > 0) ? fade/2 : 0;

    if(index == nright-2)

      blend = (step > 0) ? 128+fade/2 : fade/2;

    if(index == nright-3)

      blend = (step > 0) ? 256 : 128+fade/2;

    state->rightSlides[index].blend = blend;

  }

}

// ------------- PictureFlowSoftwareRenderer ---------------------------------------

PictureFlowSoftwareRenderer::PictureFlowSoftwareRenderer():

PictureFlowAbstractRenderer(), size(0,0), bgcolor(0), effect(-1), blankSurface(0)

{

#ifdef PICTUREFLOW_QT3

  surfaceCache.setAutoDelete(true);

#endif

}

PictureFlowSoftwareRenderer::~PictureFlowSoftwareRenderer()

{

  surfaceCache.clear();

  buffer = QImage();

  delete blankSurface;

}

void PictureFlowSoftwareRenderer::paint()

{

  if(!widget && !gWidget)

    return;

  if(widget && widget->size() != size)

    init();

  else if (gWidget && gWidget->size().toSize() != size)

    init();