/*=========================================================================

   Program: ParaView
   Module:    pqAnimationModel.cxx

   Copyright (c) 2005-2008 Sandia Corporation, Kitware Inc.
   All rights reserved.

   ParaView is a free software; you can redistribute it and/or modify it
   under the terms of the ParaView license version 1.2. 

   See License_v1.2.txt for the full ParaView license.
   A copy of this license can be obtained by contacting
   Kitware Inc.
   28 Corporate Drive
   Clifton Park, NY 12065
   USA

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR
CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

=========================================================================*/

#include "pqAnimationModel.h"

#include <QPainter>
#include <QGraphicsView>
#include <QEvent>
#include <QStyle>
#include <QGraphicsSceneMouseEvent>

#include "pqAnimationTrack.h"
#include "pqAnimationKeyFrame.h"

pqAnimationModel::pqAnimationModel(QGraphicsView* p)
  : QGraphicsScene(QRectF(0,0,400,16*6), p),
  Mode(Real), Ticks(10), CurrentTime(0), StartTime(0), EndTime(1),
  Interactive(false),
  CurrentTimeGrabbed(false),
  CurrentTrackGrabbed(NULL),
  CurrentKeyFrameGrabbed(NULL),
  CurrentKeyFrameEdge(0)
{
  QObject::connect(this, SIGNAL(sceneRectChanged(QRectF)),
                   this, SLOT(resizeTracks()));
  p->installEventFilter(this);
  this->Header.appendRow(new QStandardItem());
  this->Header.setHeaderData(0, Qt::Vertical, "Time", Qt::DisplayRole);

}

pqAnimationModel::~pqAnimationModel()
{
  while(this->Tracks.size())
    {
    this->removeTrack(this->Tracks[0]);
    }
}

QAbstractItemModel* pqAnimationModel::header()
{
  return &this->Header;
}

int pqAnimationModel::count()
{
  return this->Tracks.size();
}
pqAnimationTrack* pqAnimationModel::track(int i)
{
  if(i >= 0 && i < this->Tracks.size())
    {
    return this->Tracks[i];
    }
  return NULL;
}

pqAnimationTrack* pqAnimationModel::addTrack()
{
  pqAnimationTrack* t = new pqAnimationTrack(this);
  this->Tracks.append(t);
  this->addItem(t);
  this->resizeTracks();

  this->Header.appendRow(new QStandardItem());
  QObject::connect(t, SIGNAL(propertyChanged()),
                   this, SLOT(trackNameChanged()));
  
  return t;
}

void pqAnimationModel::removeTrack(pqAnimationTrack* t)
{
  int idx = this->Tracks.indexOf(t);
  if(idx != -1)
    {
    this->Tracks.removeAt(idx);
    this->removeItem(t);
    this->Header.removeRow(idx+1);  // off by one for time header item
    delete t;
    this->resizeTracks();
    }
}

void pqAnimationModel::resizeTracks()
{
  // give each track some height more than text height
  // if total tracks exceeds sceneRect, increase the sceneRect

  int i;
  int num = this->Tracks.size();
  QRectF rect = this->sceneRect();
  double rh = this->rowHeight();
  double requiredHeight = rh * (num+1);
  if(rect.height() != requiredHeight)
    {
    this->setSceneRect(rect.left(), rect.top(), rect.width(), requiredHeight);
    return;
    }
  
  rh = (requiredHeight -1)/double(num+1);
  double h = rh;
  for(i=0; i<num; i++)
    {
    this->Tracks[i]->setBoundingRect(QRectF(rect.left(), h, rect.width() - 1, rh));
    h += rh;
    }
}

pqAnimationModel::ModeType pqAnimationModel::mode() const
{
  return this->Mode;
}
int pqAnimationModel::ticks() const
{
  return this->Ticks;
}
double pqAnimationModel::currentTime() const
{
  return this->CurrentTime;
}
double pqAnimationModel::startTime() const
{
  return this->StartTime;
}
double pqAnimationModel::endTime() const
{
  return this->EndTime;
}

bool pqAnimationModel::interactive() const
{
  return this->Interactive;
}

void pqAnimationModel::setRowHeight(int rh)
{
  this->RowHeight = rh;
  this->resizeTracks();
}

int pqAnimationModel::rowHeight() const
{
  return this->RowHeight;
}

void pqAnimationModel::setMode(pqAnimationModel::ModeType m)
{
  this->Mode = m;
  this->update();
}
void pqAnimationModel::setTicks(int f)
{
  this->Ticks = f;
  this->update();
}

void pqAnimationModel::setTickMarks(int cnt, double* times)
{
  this->Ticks = cnt;
  this->CustomTicks.clear();
  for (int cc=0; cc < cnt; cc++)
    {
    this->CustomTicks.push_back(times[cc]);
    }
  this->update();
}

void pqAnimationModel::setCurrentTime(double t)
{
  this->CurrentTime = t;
  this->NewCurrentTime = t;
  this->update();
}
void pqAnimationModel::setStartTime(double t)
{
  this->StartTime = t;
  this->resizeTracks();
  this->update();
}
void pqAnimationModel::setEndTime(double t)
{
  this->EndTime = t;
  this->resizeTracks();
  this->update();
}

void pqAnimationModel::setInteractive(bool b)
{
  this->Interactive = b;
}

double pqAnimationModel::positionFromTime(double time)
{
  QRectF sr = this->sceneRect();
  double fraction = (time - this->StartTime) /
                    (this->EndTime - this->StartTime);
  return fraction * (sr.width()-1) + sr.left();
}

double pqAnimationModel::timeFromPosition(double pos)
{
  QRectF sr = this->sceneRect();
  double fraction = (pos - sr.left()) / (sr.width()-1);
  return fraction * (this->EndTime - this->StartTime) + this->StartTime;
}

double pqAnimationModel::timeFromTick(int tick)
{
  if (this->Mode == Custom && tick <= this->CustomTicks.size())
    {
    return this->CustomTicks[tick];
    }

  double fraction = tick / (this->Ticks-1.0);
  return fraction * (this->EndTime - this->StartTime) + this->StartTime;
}

int pqAnimationModel::tickFromTime(double time)
{
  if (this->Mode == Custom)
    {
    double error = 1.0e+299;
    int index = -1;
    int cc=0;
    foreach (double tick_time, this->CustomTicks)
      {
      if (error > qAbs(tick_time-time))
        {
        error = qAbs(tick_time-time);
        index = cc;
        }
      cc++;
      }
    if (index != -1)
      {
      return index;
      }
    }

  double fraction = (time - this->StartTime) /
    (this->EndTime - this->StartTime);
  return qRound(fraction * (this->Ticks-1.0));
}

QPolygonF pqAnimationModel::timeBarPoly(double time)
{
  int rh = this->rowHeight();
  QRectF sr = this->sceneRect();
  
  double pos = this->positionFromTime(time);
  QVector<QPointF> polyPoints;
  polyPoints.append(QPointF(pos - 4, rh - 7));
  polyPoints.append(QPointF(pos - 4, rh - 4));
  polyPoints.append(QPointF(pos - 1, rh-1));
  polyPoints.append(QPointF(pos - 1, sr.height() + sr.top()-2));
  polyPoints.append(QPointF(pos + 1, sr.height() + sr.top()-2));
  polyPoints.append(QPointF(pos + 1, rh-1));
  polyPoints.append(QPointF(pos + 4, rh - 4));
  polyPoints.append(QPointF(pos + 4, rh - 7));
  return QPolygonF(polyPoints);
}

void pqAnimationModel::drawForeground(QPainter* painter, const QRectF& )
{
  painter->save();
  
  QRectF sr = this->sceneRect();
  int rh = this->rowHeight();


  QGraphicsView* view = qobject_cast<QGraphicsView*>(this->parent());
  const QRectF labelRect = QRectF(sr.left(), sr.top(), sr.width()-1, rh);

  // make background for time labels white
  painter->save();
  painter->setBrush(QColor(255,255,255));
  painter->setPen(QColor());
  painter->drawRect(labelRect);
  painter->restore();
  
  // show rough time labels for all time modes
  // TODO  would be nice to improve the time labels
  //       match them with ticks in sequence mode
  //       don't draw labels with 'e' formatting, if its simpler or more compact
  QFontMetrics metrics(view->font());
  int num = qRound(labelRect.width() / (9 * metrics.maxWidth()));
  num = num == 0 ? 1 : num;
  double w = labelRect.width() / num;

  painter->drawText(QRectF(labelRect.left(), labelRect.top(), w/2.0, rh), 
                    Qt::AlignLeft | Qt::AlignVCenter,
                    QString("%1").arg(this->StartTime, 5, 'e', 3));

  for(int i=1; i<num; i++)
    {
    double time = this->StartTime + (this->EndTime - this->StartTime) * (double)i/(double)num;
    double left = labelRect.left() + w / 2.0 + w * (i-1);
    painter->drawText(QRectF(left, labelRect.top(), w, rh), 
                      Qt::AlignCenter, QString("%1").arg(time, 5, 'e', 3));
    }
  
  painter->drawText(QRectF(labelRect.right() - w/2.0, labelRect.top(), w/2.0, rh), 
                    Qt::AlignRight | Qt::AlignVCenter,
                    QString("%1").arg(this->EndTime, 5, 'e', 3));

  
  // if sequence, draw a tick mark for each frame
  if ((this->mode() == Sequence || this->mode() == Custom) && this->Ticks > 2)
    {
    for(int i=0; i<this->Ticks; i++)
      {
      double tickTime = this->timeFromTick(i);
      double tickPos = this->positionFromTime(tickTime);
      QLineF line(tickPos, labelRect.height(),
                  tickPos, labelRect.height()-3.0);
      painter->drawLine(line);
      }
    }
  
  // draw current time bar
  QPen pen = painter->pen();
  pen.setJoinStyle(Qt::MiterJoin);
  painter->setPen(pen);
  painter->setBrush(QColor(0,0,0));

  QPolygonF poly = this->timeBarPoly(this->CurrentTime);
  painter->drawPolygon(poly);

  if(this->NewCurrentTime != this->CurrentTime)
    {
    double pos = this->positionFromTime(this->NewCurrentTime);
    QVector<QPointF> pts;
    pts.append(QPointF(pos - 1, rh-1));
    pts.append(QPointF(pos - 1, sr.height() + sr.top()-2));
    pts.append(QPointF(pos + 1, sr.height() + sr.top()-2));
    pts.append(QPointF(pos + 1, rh-1));
    painter->setBrush(QColor(200,200,200));
    painter->drawPolygon(QPolygonF(pts));
    }
  
  painter->restore();
}
  
bool pqAnimationModel::eventFilter(QObject* w, QEvent* e)
{
  if(e->type() == QEvent::Resize)
    {
    QGraphicsView* v = qobject_cast<QGraphicsView*>(w);
    QRect sz = v->contentsRect();
    this->setSceneRect(0, 0, sz.width(), (this->Tracks.size()+1) * this->rowHeight());
    v->ensureVisible(this->sceneRect(), 0, 0);
    }
  return false;
}

void pqAnimationModel::trackNameChanged()
{
  QGraphicsView* view = qobject_cast<QGraphicsView*>(this->parent());
  QFontMetrics metrics(view->font());

  for(int i=0; i<this->Tracks.size(); i++)
    {
    this->Header.setHeaderData(i+1, Qt::Vertical, this->Tracks[i]->property(),
                               Qt::DisplayRole);
    }
}

bool pqAnimationModel::hitTestCurrentTimePoly(const QPointF& pos)
{
  QPolygonF poly = this->timeBarPoly(this->CurrentTime);
  QRectF rect = poly.boundingRect().adjusted(-1,-1,1,1);
  return rect.contains(pos);
}

pqAnimationTrack* pqAnimationModel::hitTestTracks(const QPointF& pos)
{
  QList<QGraphicsItem*> hitItems = this->items(pos);
  foreach(QGraphicsItem* i, hitItems)
    {
    if(this->Tracks.contains(static_cast<pqAnimationTrack*>(i)))
      {
      return static_cast<pqAnimationTrack*>(i);
      }
    }
  return NULL;
}

pqAnimationKeyFrame* pqAnimationModel::hitTestKeyFrame(pqAnimationTrack* t, const QPointF& pos)
{
  if(t)
    {
    for(int i=0; i<t->count(); i++)
      {
      pqAnimationKeyFrame* kf = t->keyFrame(i);
      double keyPos1 =
        this->positionFromTime(this->normalizedTimeToTime(kf->normalizedStartTime()));
      double keyPos2 =
        this->positionFromTime(this->normalizedTimeToTime(kf->normalizedEndTime()));
      if(pos.x() >= keyPos1 && pos.x() <= keyPos2)
        {
        return kf;
        }
      }
    }

  return NULL;
}

void pqAnimationModel::mouseDoubleClickEvent(QGraphicsSceneMouseEvent* mouseEvent)
{
  if(mouseEvent->button() == Qt::LeftButton)
    {
    QPointF pos = mouseEvent->scenePos();
    pqAnimationTrack* t = hitTestTracks(pos);
    if(t)
      {
      emit trackSelected(t);
      return;
      }
    }
}

void pqAnimationModel::mousePressEvent(QGraphicsSceneMouseEvent* mouseEvent)
{
  if(!this->Interactive || mouseEvent->button() != Qt::LeftButton)
    {
    return;
    }

  // see if current time is grabbed
  QPointF pos = mouseEvent->scenePos();
  if(this->hitTestCurrentTimePoly(pos))
    {
    this->CurrentTimeGrabbed = true;
    this->InteractiveRange.first = this->StartTime;
    this->InteractiveRange.second = this->EndTime;
    }
  
  // see if any keyframe is grabbed
  if(!this->CurrentTimeGrabbed)
    {
    pqAnimationTrack* t = hitTestTracks(pos);
    pqAnimationKeyFrame* kf = hitTestKeyFrame(t, pos);

    if(t && kf)
      {
      int whichkf = 0;
      for(whichkf=0; whichkf<t->count(); whichkf++)
        {
        if(t->keyFrame(whichkf) == kf)
          {
          break;
          }
        }

      if(kf)
        {
        double keyPos1 =
          this->positionFromTime(this->normalizedTimeToTime(kf->normalizedStartTime()));
        double keyPos2 =
          this->positionFromTime(this->normalizedTimeToTime(kf->normalizedEndTime()));
        if(qAbs(keyPos1 - pos.x()) < 3)
          {
          this->CurrentTrackGrabbed = t;
          this->CurrentKeyFrameGrabbed = kf;
          this->CurrentKeyFrameEdge = 0;
          }
        else if(qAbs(keyPos2 - pos.x()) < 3)
          {
          whichkf++;
          this->CurrentTrackGrabbed = t;
          this->CurrentKeyFrameGrabbed = kf;
          this->CurrentKeyFrameEdge = 1;
          this->InteractiveRange.first = this->StartTime;
          this->InteractiveRange.second = this->EndTime;
          }
        
        if(whichkf > 0)
          {
          this->InteractiveRange.first =
            this->normalizedTimeToTime(
              t->keyFrame(whichkf-1)->normalizedStartTime());
          }
        else
          {
          this->InteractiveRange.first = this->StartTime;
          }
        
        if(whichkf < t->count())
          {
          this->InteractiveRange.second =
            this->normalizedTimeToTime(
              t->keyFrame(whichkf)->normalizedEndTime());
          }
        else
          {
          this->InteractiveRange.second = this->EndTime;
          }
        }
      }
    }

  // gather some snap hints from the current time
  // and all the keyframes
  if(this->CurrentTimeGrabbed || this->CurrentTrackGrabbed)
    {
    this->SnapHints.append(this->CurrentTime);

    for(int i=0; i<this->count(); i++)
      {
      pqAnimationTrack* t = this->track(i);
      for(int j=0; j<t->count(); j++)
        {
        pqAnimationKeyFrame* kf = t->keyFrame(j);
        this->SnapHints.append(
          this->normalizedTimeToTime(kf->normalizedStartTime()));
        this->SnapHints.append(
          this->normalizedTimeToTime(kf->normalizedEndTime()));
        }
      }
    }

}

void pqAnimationModel::mouseMoveEvent(QGraphicsSceneMouseEvent* mouseEvent)
{
  if(!this->Interactive)
    {
    return;
    }

  QPointF pos = mouseEvent->scenePos();
  
  if(this->CurrentTimeGrabbed || this->CurrentKeyFrameGrabbed)
    {
    double time = this->timeFromPosition(pos.x());

    // snap to ticks in sequence mode
    // (should snap to hints if we find one closer? )
    if (this->mode() == Sequence || this->mode() == Custom)
      {
      int tick = this->tickFromTime(time);
      time = this->timeFromTick(tick);
      }
    else
      {
      // snap to nearby snap hints (if any)
      for(int i=0; i<this->SnapHints.size(); i++)
        {
        if(qAbs(this->positionFromTime(this->SnapHints[i]) -
                this->positionFromTime(time)) < 3)
          {
          time = this->SnapHints[i];
          break;
          }
        }
      }
    
    // clamp to start/end time
    time = qMax(time, this->InteractiveRange.first);
    time = qMin(time, this->InteractiveRange.second);

    this->NewCurrentTime = time;
    this->update();
    return;
    }
 

  // we haven't gone in any interaction mode yet,
  // so lets adjust the cursor to give indication of being
  // able to interact if the mouse was pressed at this location 
  QGraphicsView* view = qobject_cast<QGraphicsView*>(this->parent());
  
  if(this->hitTestCurrentTimePoly(pos))
    {
    view->setCursor(QCursor(Qt::SizeHorCursor));
    return;
    }

  // see if we're at the edge of any keyframe
  pqAnimationTrack* t = hitTestTracks(pos);
  pqAnimationKeyFrame* kf = hitTestKeyFrame(t, pos);
  if(kf)
    {
    double keyPos1 =
      this->positionFromTime(this->normalizedTimeToTime(kf->normalizedStartTime()));
    double keyPos2 =
      this->positionFromTime(this->normalizedTimeToTime(kf->normalizedEndTime()));
    if(qAbs(keyPos1 - pos.x()) < 3 || qAbs(keyPos2 - pos.x()) < 3)
      {
      view->setCursor(QCursor(Qt::SizeHorCursor));
      return;
      }
    }
  
  // in case cursor was changed elsewhere
  view->setCursor(QCursor());
}

void pqAnimationModel::mouseReleaseEvent(QGraphicsSceneMouseEvent*)
{
  if(this->CurrentTimeGrabbed)
    {
    this->CurrentTimeGrabbed = false;
    emit this->currentTimeSet(this->NewCurrentTime);
    this->NewCurrentTime = this->CurrentTime;
    this->update();
    }

  if(this->CurrentKeyFrameGrabbed)
    {
    emit this->keyFrameTimeChanged(this->CurrentTrackGrabbed, 
      this->CurrentKeyFrameGrabbed, this->CurrentKeyFrameEdge,
      this->NewCurrentTime);

    this->CurrentTrackGrabbed = NULL;
    this->CurrentKeyFrameGrabbed = NULL;
    this->NewCurrentTime = this->CurrentTime;
    this->update();
    }

  this->SnapHints.clear();

}

double pqAnimationModel::timeToNormalizedTime(double t) const
{
  return (t - this->startTime()) / (this->endTime() - this->startTime());
}

double pqAnimationModel::normalizedTimeToTime(double t) const
{
  return t * (this->endTime() - this->startTime()) + this->startTime();
}


