/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* ***** BEGIN LICENSE BLOCK *****
 * Version: MPL 1.1/GPL 2.0/LGPL 2.1
 *
 * The contents of this file are subject to the Mozilla Public License Version
 * 1.1 (the "License"); you may not use this file except in compliance with
 * the License. You may obtain a copy of the License at
 * http://www.mozilla.org/MPL/
 *
 * Software distributed under the License is distributed on an "AS IS" basis,
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
 * for the specific language governing rights and limitations under the
 * License.
 *
 * The Original Code is the Mozilla SVG project.
 *
 * The Initial Developer of the Original Code is IBM Corporation.
 * Portions created by the Initial Developer are Copyright (C) 2005
 * the Initial Developer. All Rights Reserved.
 *
 * Contributor(s):
 *
 * Alternatively, the contents of this file may be used under the terms of
 * either of the GNU General Public License Version 2 or later (the "GPL"),
 * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
 * in which case the provisions of the GPL or the LGPL are applicable instead
 * of those above. If you wish to allow use of your version of this file only
 * under the terms of either the GPL or the LGPL, and not to allow others to
 * use your version of this file under the terms of the MPL, indicate your
 * decision by deleting the provisions above and replace them with the notice
 * and other provisions required by the GPL or the LGPL. If you do not delete
 * the provisions above, a recipient may use your version of this file under
 * the terms of any one of the MPL, the GPL or the LGPL.
 *
 * ***** END LICENSE BLOCK ***** */

#include "nsSVGFilterFrame.h"
#include "nsIDocument.h"
#include "nsISVGValueUtils.h"
#include "nsSVGMatrix.h"
#include "nsSVGOuterSVGFrame.h"
#include "nsGkAtoms.h"
#include "nsSVGUtils.h"
#include "nsSVGFilterElement.h"
#include "nsSVGFilterInstance.h"
#include "nsSVGFilters.h"
#include "gfxASurface.h"
#include "gfxContext.h"
#include "gfxImageSurface.h"

nsIFrame*
NS_NewSVGFilterFrame(nsIPresShell* aPresShell, nsIContent* aContent, nsStyleContext* aContext)
{
  nsCOMPtr<nsIDOMSVGFilterElement> filter = do_QueryInterface(aContent);
  if (!filter) {
    NS_ERROR("Can't create frame! Content is not an SVG filter");
    return nsnull;
  }

  return new (aPresShell) nsSVGFilterFrame(aContext);
}

nsIContent *
NS_GetSVGFilterElement(nsIURI *aURI, nsIContent *aContent)
{
  nsIContent* content = nsContentUtils::GetReferencedElement(aURI, aContent);

  nsCOMPtr<nsIDOMSVGFilterElement> filter = do_QueryInterface(content);
  if (filter)
    return content;

  return nsnull;
}

void
nsSVGFilterFrame::FilterFailCleanup(nsSVGRenderState *aContext,
                                    nsISVGChildFrame *aTarget)
{
  aTarget->SetOverrideCTM(nsnull);
  aTarget->SetMatrixPropagation(PR_TRUE);
  aTarget->NotifySVGChanged(nsISVGChildFrame::SUPPRESS_INVALIDATION |
                            nsISVGChildFrame::TRANSFORM_CHANGED);
  aTarget->PaintSVG(aContext, nsnull);
}

/**
 * This class builds a graph of the filter image data flow, essentially
 * converting the filter graph to SSA. This lets us easily propagate
 * analysis data (such as bounding-boxes) over the filter primitive graph.
 * XXX In the future we could extend this to propagate other information
 * such as whether images are opaque, whether they're alpha-only,
 * and color models... We should also compute and store filter primitive
 * subregions here, and use this graph for drawing to
 * eliminate the need for an image dictionary at draw time.
 */
class FilterAnalysis {
public:
  FilterAnalysis(const nsRect& aSourceBBox, const nsRect& aFilterEffectsRegion,
                 const nsSVGFilterInstance& aInstance)
    : mFilterEffectsRegion(aFilterEffectsRegion), mInstance(&aInstance)
  {
    mSourceColorAlphaInfo.mResultBoundingBox = aSourceBBox;
    mSourceAlphaInfo.mResultBoundingBox = aSourceBBox;
  }
  
  // Build graph of Info nodes describing filter primitives
  nsresult SetupGraph(nsIContent* aFilterElement);
  // Compute bounding boxes of the filter primitive outputs
  void ComputeResultBoundingBoxes();
  // Compute bounding boxes of what we actually *need* from the filter
  // primitive outputs
  void ComputeNeededBoxes();
  nsRect ComputeUnionOfAllNeededBoxes();
  const nsRect& GetSourceColorAlphaNeeded()
  { return mSourceColorAlphaInfo.mResultNeededBox; }
  const nsRect& GetSourceAlphaNeeded()
  { return mSourceAlphaInfo.mResultNeededBox; }

private:
  struct Info {
    nsSVGFE* mFE;
    nsRect   mResultBoundingBox;
    nsRect   mResultNeededBox;
  
    // Can't use nsAutoTArray here, because these Info objects
    // live in nsTArrays themselves and nsTArray moves the elements
    // around in memory, which breaks nsAutoTArray.
    nsTArray<Info*> mInputs;

    Info() : mFE(nsnull) {}
  };

  class ImageAnalysisEntry : public nsStringHashKey {
  public:
    ImageAnalysisEntry(KeyTypePointer aStr) : nsStringHashKey(aStr) { }
    ImageAnalysisEntry(const ImageAnalysisEntry& toCopy) : nsStringHashKey(toCopy),
      mInfo(toCopy.mInfo) { }

    Info* mInfo;
  };

  nsRect mFilterEffectsRegion;
  const nsSVGFilterInstance* mInstance;

  Info mSourceColorAlphaInfo;
  Info mSourceAlphaInfo;
  nsTArray<Info> mFilterInfo;
};

nsresult
FilterAnalysis::SetupGraph(nsIContent* aFilterElement)
{
  // First build mFilterInfo. It's important that we don't change that
  // array after we start storing pointers to its elements!
  PRUint32 count = aFilterElement->GetChildCount();
  PRUint32 i;
  for (i = 0; i < count; ++i) {
    nsIContent* child = aFilterElement->GetChildAt(i);
    nsRefPtr<nsSVGFE> filter;
    CallQueryInterface(child, (nsSVGFE**)getter_AddRefs(filter));
    if (!filter)
      continue;

    Info* info = mFilterInfo.AppendElement();
    info->mFE = filter;
  }

  // Now fill in all the links
  nsTHashtable<ImageAnalysisEntry> imageTable;
  imageTable.Init(10);

  for (i = 0; i < mFilterInfo.Length(); ++i) {
    Info* info = &mFilterInfo[i];
    nsSVGFE* filter = info->mFE;
    nsAutoTArray<nsIDOMSVGAnimatedString*,2> sources;
    filter->GetSourceImageNames(&sources);
 
    for (PRUint32 j=0; j<sources.Length(); ++j) {
      nsAutoString str;
      sources[j]->GetAnimVal(str);
      Info* sourceInfo;

      if (str.EqualsLiteral("SourceGraphic")) {
        sourceInfo = &mSourceColorAlphaInfo;
      } else if (str.EqualsLiteral("SourceAlpha")) {
        sourceInfo = &mSourceAlphaInfo;
      } else if (str.EqualsLiteral("BackgroundImage") ||
                 str.EqualsLiteral("BackgroundAlpha") ||
                 str.EqualsLiteral("FillPaint") ||
                 str.EqualsLiteral("StrokePaint")) {
        return NS_ERROR_NOT_IMPLEMENTED;
      } else if (str.EqualsLiteral("")) {
        sourceInfo = i == 0 ? &mSourceColorAlphaInfo : &mFilterInfo[i - 1];
      } else {
        ImageAnalysisEntry* entry = imageTable.GetEntry(str);
        if (!entry)
          return NS_ERROR_FAILURE;
        sourceInfo = entry->mInfo;
      }
      
      info->mInputs.AppendElement(sourceInfo);
    }

    nsAutoString str;
    filter->GetResultImageName()->GetAnimVal(str);
    ImageAnalysisEntry* entry = imageTable.PutEntry(str);
    if (entry) {
      entry->mInfo = info;
    }
  }

  return NS_OK;
}

void
FilterAnalysis::ComputeResultBoundingBoxes()
{
  for (PRUint32 i = 0; i < mFilterInfo.Length(); ++i) {
    Info* info = &mFilterInfo[i];
    nsAutoTArray<nsRect,2> sourceBBoxes;
    for (PRUint32 j = 0; j < info->mInputs.Length(); ++j) {
      sourceBBoxes.AppendElement(info->mInputs[j]->mResultBoundingBox);
    }
    
    nsRect resultBBox = info->mFE->ComputeTargetBBox(sourceBBoxes, *mInstance);
    // XXX at some point we should clip this to the filter primitive subregion
    // as well
    resultBBox.IntersectRect(resultBBox, mFilterEffectsRegion);
    info->mResultBoundingBox = resultBBox;
  }
}

void
FilterAnalysis::ComputeNeededBoxes()
{
  if (mFilterInfo.IsEmpty())
    return;

  // In the end, we need whatever the final filter primitive will draw.
  // XXX we could optimize this by intersecting with the dirty rect here!!!
  mFilterInfo[mFilterInfo.Length() - 1].mResultNeededBox
    = mFilterInfo[mFilterInfo.Length() - 1].mResultBoundingBox;

  for (PRInt32 i = mFilterInfo.Length() - 1; i >= 0; --i) {
    Info* info = &mFilterInfo[i];
    nsAutoTArray<nsRect,2> sourceBBoxes;
    for (PRUint32 j = 0; j < info->mInputs.Length(); ++j) {
      sourceBBoxes.AppendElement(info->mInputs[j]->mResultBoundingBox);
    }
    
    info->mFE->ComputeNeededSourceBBoxes(
      mFilterInfo[i].mResultNeededBox, sourceBBoxes, *mInstance);
    // Update each source with the rectangle we need
    for (PRUint32 j = 0; j < info->mInputs.Length(); ++j) {
      nsRect* r = &info->mInputs[j]->mResultNeededBox;
      r->UnionRect(*r, sourceBBoxes[j]);
      // Keep everything within the filter effects region
      // XXX at some point we should clip to the filter primitive subregion
      // as well
      r->IntersectRect(*r, mFilterEffectsRegion);
    }
  }
}

nsRect
FilterAnalysis::ComputeUnionOfAllNeededBoxes()
{
  nsRect r;
  r.UnionRect(mSourceColorAlphaInfo.mResultNeededBox,
              mSourceAlphaInfo.mResultNeededBox);
  for (PRUint32 i = 0; i < mFilterInfo.Length(); ++i) {
    r.UnionRect(r, mFilterInfo[i].mResultNeededBox);
  }
  return r;
}

// XXX only works with matrices that are a translation + scale!
static nsRect
TransformBBox(nsIDOMSVGRect *aBBox, nsIDOMSVGMatrix *aMatrix,
              const nsRect& aBounds)
{
  if (!aBBox) {
    // No bbox means empty bbox (from nsSVGUseFrame at least); just
    // return an empty rect
    return nsRect();
  }
 
  float bboxX, bboxY, bboxWidth, bboxHeight;
  aBBox->GetX(&bboxX);
  aBBox->GetY(&bboxY);
  aBBox->GetWidth(&bboxWidth);
  aBBox->GetHeight(&bboxHeight);

  float bboxXMost = bboxX + bboxWidth;
  float bboxYMost = bboxY + bboxHeight;
  nsSVGUtils::TransformPoint(aMatrix, &bboxX, &bboxY);
  nsSVGUtils::TransformPoint(aMatrix, &bboxXMost, &bboxYMost);

  nsRect r;
  r.x = NSToIntFloor(PR_MAX(aBounds.x, bboxX));
  r.y = NSToIntFloor(PR_MAX(aBounds.y, bboxY));
  r.width = NSToIntCeil(PR_MIN(aBounds.XMost(), bboxXMost)) - r.x;
  r.height = NSToIntCeil(PR_MIN(aBounds.YMost(), bboxYMost)) - r.y;
  return r;
}

nsresult
nsSVGFilterFrame::FilterPaint(nsSVGRenderState *aContext,
                              nsISVGChildFrame *aTarget)
{
  nsCOMPtr<nsIDOMSVGFilterElement> aFilter = do_QueryInterface(mContent);
  NS_ASSERTION(aFilter, "Wrong content element (not filter)");

  nsIFrame *frame;
  CallQueryInterface(aTarget, &frame);

  nsCOMPtr<nsIDOMSVGMatrix> ctm = nsSVGUtils::GetCanvasTM(frame);

  nsSVGElement *target = static_cast<nsSVGElement*>(frame->GetContent());

  aTarget->SetMatrixPropagation(PR_FALSE);
  aTarget->NotifySVGChanged(nsISVGChildFrame::SUPPRESS_INVALIDATION |
                            nsISVGChildFrame::TRANSFORM_CHANGED);

  nsSVGFilterElement *filter = static_cast<nsSVGFilterElement*>(mContent);

  float x, y, width, height;
  nsCOMPtr<nsIDOMSVGRect> bbox;
  aTarget->GetBBox(getter_AddRefs(bbox));

  nsSVGLength2 *tmpX, *tmpY, *tmpWidth, *tmpHeight;
  tmpX = &filter->mLengthAttributes[nsSVGFilterElement::X];
  tmpY = &filter->mLengthAttributes[nsSVGFilterElement::Y];
  tmpWidth = &filter->mLengthAttributes[nsSVGFilterElement::WIDTH];
  tmpHeight = &filter->mLengthAttributes[nsSVGFilterElement::HEIGHT];

  PRUint16 units =
    filter->mEnumAttributes[nsSVGFilterElement::FILTERUNITS].GetAnimValue();

  // Compute filter effects region as per spec
  if (units == nsIDOMSVGUnitTypes::SVG_UNIT_TYPE_OBJECTBOUNDINGBOX) {
    if (!bbox) {
      aTarget->SetMatrixPropagation(PR_TRUE);
      aTarget->NotifySVGChanged(nsISVGChildFrame::SUPPRESS_INVALIDATION |
                                nsISVGChildFrame::TRANSFORM_CHANGED);
      return NS_OK;
    }

    bbox->GetX(&x);
    x += nsSVGUtils::ObjectSpace(bbox, tmpX);
    bbox->GetY(&y);
    y += nsSVGUtils::ObjectSpace(bbox, tmpY);
    width = nsSVGUtils::ObjectSpace(bbox, tmpWidth);
    height = nsSVGUtils::ObjectSpace(bbox, tmpHeight);
  } else {
    x = nsSVGUtils::UserSpace(target, tmpX);
    y = nsSVGUtils::UserSpace(target, tmpY);
    width = nsSVGUtils::UserSpace(target, tmpWidth);
    height = nsSVGUtils::UserSpace(target, tmpHeight);
  }
  
  PRBool resultOverflows;
  gfxIntSize filterRes;

  // Compute size of filter buffer
  if (mContent->HasAttr(kNameSpaceID_None, nsGkAtoms::filterRes)) {
    PRInt32 filterResX, filterResY;
    filter->GetAnimatedIntegerValues(&filterResX, &filterResY, nsnull);

    filterRes =
      nsSVGUtils::ConvertToSurfaceSize(gfxSize(filterResX, filterResY),
                                       &resultOverflows);
  } else {
    float scale = nsSVGUtils::MaxExpansion(ctm);
#ifdef DEBUG_tor
    fprintf(stderr, "scale: %f\n", scale);
#endif

    filterRes =
      nsSVGUtils::ConvertToSurfaceSize(gfxSize(width, height) * scale,
                                       &resultOverflows);
  }


  // 0 disables rendering, < 0 is error
  if (filterRes.width <= 0 || filterRes.height <= 0) {
    aTarget->SetMatrixPropagation(PR_TRUE);
    aTarget->NotifySVGChanged(nsISVGChildFrame::SUPPRESS_INVALIDATION |
                              nsISVGChildFrame::TRANSFORM_CHANGED);
    return NS_OK;
  }

#ifdef DEBUG_tor
  fprintf(stderr, "filter bbox: %f,%f  %fx%f\n", x, y, width, height);
  fprintf(stderr, "filterRes: %u %u\n", filterRes.width, filterRes.height);
#endif

  nsCOMPtr<nsIDOMSVGMatrix> filterTransform;
  NS_NewSVGMatrix(getter_AddRefs(filterTransform),
                  filterRes.width / width,      0.0f,
                  0.0f,                         filterRes.height / height,
                  -x * filterRes.width / width, -y * filterRes.height / height);
  aTarget->SetOverrideCTM(filterTransform);
  aTarget->NotifySVGChanged(nsISVGChildFrame::SUPPRESS_INVALIDATION |
                            nsISVGChildFrame::TRANSFORM_CHANGED);

  PRUint16 primitiveUnits =
    filter->mEnumAttributes[nsSVGFilterElement::PRIMITIVEUNITS].GetAnimValue();

  nsSVGFilterInstance::ColorModel 
    colorModel(nsSVGFilterInstance::ColorModel::SRGB,
               nsSVGFilterInstance::ColorModel::PREMULTIPLIED);

  // Setup instance data
  nsSVGFilterInstance instance(target, bbox,
                               x, y, width, height,
                               filterRes.width, filterRes.height,
                               primitiveUnits);
  
  // Compute the smallest buffer size that can contain the rendering of
  // all filter components. We also compute whether we need
  // the source image and/or alpha (and which region of each we need,
  // XXX although we don't use that yet).
  nsRect filterBounds(0, 0, filterRes.width, filterRes.height);
  nsRect sourceBounds = TransformBBox(bbox, filterTransform, filterBounds);
  FilterAnalysis analysis(sourceBounds, filterBounds, instance);

  nsresult rv = analysis.SetupGraph(mContent);
  if (NS_FAILED(rv)) {
    FilterFailCleanup(aContext, aTarget);
    return NS_OK;
  }
  analysis.ComputeResultBoundingBoxes();
  analysis.ComputeNeededBoxes();

  // set the dimensions for all surfaces to the bounding box of all needed
  // images.
  // These surfaces use device offsets to position themselves inside our
  // filter effects region.
  // XXX this isn't optimal, we really should be able to use different
  // sizes for different images!
  instance.SetSurfaceRect(analysis.ComputeUnionOfAllNeededBoxes());
  if (instance.GetSurfaceRect().IsEmpty())
    return NS_OK;

  if (!analysis.GetSourceColorAlphaNeeded().IsEmpty() ||
      !analysis.GetSourceAlphaNeeded().IsEmpty()) {
    // paint the target geometry
    nsRefPtr<gfxImageSurface> tmpSurface = instance.GetImage();
    if (!tmpSurface) {
      FilterFailCleanup(aContext, aTarget);
      return NS_OK;
    }

    // XXX now that we can compute which region of the source will
    // actually be needed, we could speed this up
    gfxContext tmpContext(tmpSurface);
    nsSVGRenderState tmpState(&tmpContext);
    tmpContext.SetOperator(gfxContext::OPERATOR_OVER);
    aTarget->PaintSVG(&tmpState, nsnull);

    if (!analysis.GetSourceAlphaNeeded().IsEmpty()) {
      nsRefPtr<gfxImageSurface> alpha = instance.GetImage();
      if (!alpha) {
        FilterFailCleanup(aContext, aTarget);
        return NS_OK;
      }

      PRUint8 *data = tmpSurface->Data();
      PRUint8 *alphaData = alpha->Data();
      PRUint32 stride = tmpSurface->Stride();
 
      for (PRInt32 yy = 0; yy < instance.GetSurfaceHeight(); yy++)
        for (PRInt32 xx = 0; xx < instance.GetSurfaceWidth(); xx++) {
          alphaData[stride*yy + 4*xx + GFX_ARGB32_OFFSET_B] = 0;
          alphaData[stride*yy + 4*xx + GFX_ARGB32_OFFSET_G] = 0;
          alphaData[stride*yy + 4*xx + GFX_ARGB32_OFFSET_R] = 0;
          alphaData[stride*yy + 4*xx + GFX_ARGB32_OFFSET_A] =
            data[stride*yy + 4*xx + GFX_ARGB32_OFFSET_A];
        }

      instance.DefineImage(NS_LITERAL_STRING("SourceAlpha"), alpha,
                           nsRect(0, 0, filterRes.width, filterRes.height),
                           colorModel);
    }

    // this always needs to be defined last because the default image
    // for the first filter element is supposed to be SourceGraphic
    instance.DefineImage(NS_LITERAL_STRING("SourceGraphic"), tmpSurface,
                         nsRect(0, 0, filterRes.width, filterRes.height),
                         colorModel);
  } else {
    // XXX We shouldn't really need to set up a temporary surface here,
    // but we have to because all filter primitives currently need to
    // call AcquireSourceImage and find a source image, even if they don't
    // use it!
    nsRefPtr<gfxImageSurface> tmpSurface = instance.GetImage();
    if (!tmpSurface) {
      FilterFailCleanup(aContext, aTarget);
      return NS_OK;
    }
    instance.DefineImage(NS_LITERAL_STRING("SourceGraphic"), tmpSurface,
                         nsRect(0, 0, filterRes.width, filterRes.height),
                         colorModel);
  }

  // Now invoke the components of the filter chain
  PRUint32 count = mContent->GetChildCount();
  for (PRUint32 k=0; k<count; ++k) {
    nsIContent* child = mContent->GetChildAt(k);
    nsRefPtr<nsSVGFE> filter;
    CallQueryInterface(child, (nsSVGFE**)getter_AddRefs(filter));
    if (filter && NS_FAILED(filter->Filter(&instance))) {
      FilterFailCleanup(aContext, aTarget);
      return NS_OK;
    }
  }

  nsRect filterRect;
  nsRefPtr<gfxImageSurface> filterSurface;

  instance.LookupImage(NS_LITERAL_STRING(""),
                       getter_AddRefs(filterSurface), &filterRect, colorModel);

  if (!filterSurface) {
    FilterFailCleanup(aContext, aTarget);
    return NS_OK;
  }

  nsCOMPtr<nsIDOMSVGMatrix> scale, fini;
  NS_NewSVGMatrix(getter_AddRefs(scale),
                  width / filterRes.width, 0.0f,
                  0.0f, height / filterRes.height,
                  x, y);

  ctm->Multiply(scale, getter_AddRefs(fini));

  nsSVGUtils::CompositeSurfaceMatrix(aContext->GetGfxContext(),
                                     filterSurface, fini, 1.0);

  aTarget->SetOverrideCTM(nsnull);
  aTarget->SetMatrixPropagation(PR_TRUE);
  aTarget->NotifySVGChanged(nsISVGChildFrame::SUPPRESS_INVALIDATION |
                            nsISVGChildFrame::TRANSFORM_CHANGED);

  return NS_OK;
}

nsRect
nsSVGFilterFrame::GetInvalidationRegion(nsIFrame *aTarget)
{
  nsSVGElement *targetContent =
    static_cast<nsSVGElement*>(aTarget->GetContent());
  nsISVGChildFrame *svg;

  nsCOMPtr<nsIDOMSVGMatrix> ctm = nsSVGUtils::GetCanvasTM(aTarget);

  CallQueryInterface(aTarget, &svg);

  nsSVGFilterElement *filter = static_cast<nsSVGFilterElement*>(mContent);

  PRUint16 type =
    filter->mEnumAttributes[nsSVGFilterElement::FILTERUNITS].GetAnimValue();

  float x, y, width, height;
  nsCOMPtr<nsIDOMSVGRect> bbox;

  svg->SetMatrixPropagation(PR_FALSE);
  svg->NotifySVGChanged(nsISVGChildFrame::SUPPRESS_INVALIDATION |
                        nsISVGChildFrame::TRANSFORM_CHANGED);

  svg->GetBBox(getter_AddRefs(bbox));

  svg->SetMatrixPropagation(PR_TRUE);
  svg->NotifySVGChanged(nsISVGChildFrame::SUPPRESS_INVALIDATION |
                        nsISVGChildFrame::TRANSFORM_CHANGED);

  nsSVGLength2 *tmpX, *tmpY, *tmpWidth, *tmpHeight;
  tmpX = &filter->mLengthAttributes[nsSVGFilterElement::X];
  tmpY = &filter->mLengthAttributes[nsSVGFilterElement::Y];
  tmpWidth = &filter->mLengthAttributes[nsSVGFilterElement::WIDTH];
  tmpHeight = &filter->mLengthAttributes[nsSVGFilterElement::HEIGHT];

  if (type == nsIDOMSVGUnitTypes::SVG_UNIT_TYPE_OBJECTBOUNDINGBOX) {
    if (!bbox)
      return nsRect();

    bbox->GetX(&x);
    x += nsSVGUtils::ObjectSpace(bbox, tmpX);
    bbox->GetY(&y);
    y += nsSVGUtils::ObjectSpace(bbox, tmpY);
    width = nsSVGUtils::ObjectSpace(bbox, tmpWidth);
    height = nsSVGUtils::ObjectSpace(bbox, tmpHeight);
  } else {
    x = nsSVGUtils::UserSpace(targetContent, tmpX);
    y = nsSVGUtils::UserSpace(targetContent, tmpY);
    width = nsSVGUtils::UserSpace(targetContent, tmpWidth);
    height = nsSVGUtils::UserSpace(targetContent, tmpHeight);
  }

#ifdef DEBUG_tor
  fprintf(stderr, "invalidate box: %f,%f %fx%f\n", x, y, width, height);
#endif

  // transform back
  float xx[4], yy[4];
  xx[0] = x;          yy[0] = y;
  xx[1] = x + width;  yy[1] = y;
  xx[2] = x + width;  yy[2] = y + height;
  xx[3] = x;          yy[3] = y + height;

  nsSVGUtils::TransformPoint(ctm, &xx[0], &yy[0]);
  nsSVGUtils::TransformPoint(ctm, &xx[1], &yy[1]);
  nsSVGUtils::TransformPoint(ctm, &xx[2], &yy[2]);
  nsSVGUtils::TransformPoint(ctm, &xx[3], &yy[3]);

  float xmin, xmax, ymin, ymax;
  xmin = xmax = xx[0];
  ymin = ymax = yy[0];
  for (int i=1; i<4; i++) {
    if (xx[i] < xmin)
      xmin = xx[i];
    if (yy[i] < ymin)
      ymin = yy[i];
    if (xx[i] > xmax)
      xmax = xx[i];
    if (yy[i] > ymax)
      ymax = yy[i];
  }

#ifdef DEBUG_tor
  fprintf(stderr, "xform bound: %f %f  %f %f\n", xmin, ymin, xmax, ymax);
#endif

  return nsSVGUtils::ToBoundingPixelRect(xmin, ymin, xmax, ymax);
}

nsIAtom *
nsSVGFilterFrame::GetType() const
{
  return nsGkAtoms::svgFilterFrame;
}

// ----------------------------------------------------------------
// nsSVGFilterInstance

float
nsSVGFilterInstance::GetPrimitiveLength(nsSVGLength2 *aLength) const
{
  float value;
  if (mPrimitiveUnits == nsIDOMSVGUnitTypes::SVG_UNIT_TYPE_OBJECTBOUNDINGBOX)
    value = nsSVGUtils::ObjectSpace(mTargetBBox, aLength);
  else
    value = nsSVGUtils::UserSpace(mTarget, aLength);

  switch (aLength->GetCtxType()) {
  case nsSVGUtils::X:
    return value * mFilterResX / mFilterWidth;
  case nsSVGUtils::Y:
    return value * mFilterResY / mFilterHeight;
  case nsSVGUtils::XY:
  default:
    return value *
      sqrt(float(mFilterResX * mFilterResX + mFilterResY * mFilterResY)) /
      sqrt(mFilterWidth * mFilterWidth + mFilterHeight * mFilterHeight);
  }
}

void
nsSVGFilterInstance::GetFilterSubregion(
  nsIContent *aFilter,
  nsRect defaultRegion,
  nsRect *result)
{
  nsSVGFE *fE = static_cast<nsSVGFE*>(aFilter);
  nsSVGLength2 *tmpX, *tmpY, *tmpWidth, *tmpHeight;

  tmpX = &fE->mLengthAttributes[nsSVGFE::X];
  tmpY = &fE->mLengthAttributes[nsSVGFE::Y];
  tmpWidth = &fE->mLengthAttributes[nsSVGFE::WIDTH];
  tmpHeight = &fE->mLengthAttributes[nsSVGFE::HEIGHT];

  float x, y, width, height;
  if (mPrimitiveUnits == nsIDOMSVGUnitTypes::SVG_UNIT_TYPE_OBJECTBOUNDINGBOX) {
    mTargetBBox->GetX(&x);
    x     += nsSVGUtils::ObjectSpace(mTargetBBox, tmpX);
    mTargetBBox->GetY(&y);
    y     += nsSVGUtils::ObjectSpace(mTargetBBox, tmpY);
    width  = nsSVGUtils::ObjectSpace(mTargetBBox, tmpWidth);
    height = nsSVGUtils::ObjectSpace(mTargetBBox, tmpHeight);
  } else {
    x      = nsSVGUtils::UserSpace(mTarget, tmpX);
    y      = nsSVGUtils::UserSpace(mTarget, tmpY);
    width  = nsSVGUtils::UserSpace(mTarget, tmpWidth);
    height = nsSVGUtils::UserSpace(mTarget, tmpHeight);
  }

#ifdef DEBUG_tor
  fprintf(stderr, "GFS[1]: %f %f %f %f\n", x, y, width, height);
#endif

  nsRect filter, region;

  filter.x = 0;
  filter.y = 0;
  filter.width = mFilterResX;
  filter.height = mFilterResY;

  // XXX this needs to round out
  region.x      = (x - mFilterX) * mFilterResX / mFilterWidth;
  region.y      = (y - mFilterY) * mFilterResY / mFilterHeight;
  region.width  =          width * mFilterResX / mFilterWidth;
  region.height =         height * mFilterResY / mFilterHeight;

#ifdef DEBUG_tor
  fprintf(stderr, "GFS[2]: %d %d %d %d\n",
          region.x, region.y, region.width, region.height);
#endif

  if (!aFilter->HasAttr(kNameSpaceID_None, nsGkAtoms::x))
    region.x = defaultRegion.x;
  if (!aFilter->HasAttr(kNameSpaceID_None, nsGkAtoms::y))
    region.y = defaultRegion.y;
  if (!aFilter->HasAttr(kNameSpaceID_None, nsGkAtoms::width))
    region.width = defaultRegion.width;
  if (!aFilter->HasAttr(kNameSpaceID_None, nsGkAtoms::height))
    region.height = defaultRegion.height;

  result->IntersectRect(filter, region);

#ifdef DEBUG_tor
  fprintf(stderr, "GFS[3]: %d %d %d %d\n",
          result->x, result->y, result->width, result->height);
#endif
}

already_AddRefed<gfxImageSurface>
nsSVGFilterInstance::GetImage()
{
  nsRefPtr<gfxImageSurface> surface =
    new gfxImageSurface(gfxIntSize(mSurfaceRect.width, mSurfaceRect.height),
                        gfxASurface::ImageFormatARGB32);

  if (!surface || surface->CairoStatus()) {
    return nsnull;
  }

  surface->SetDeviceOffset(gfxPoint(-mSurfaceRect.x, -mSurfaceRect.y));
  mSurfaceStride = surface->Stride();

  gfxContext ctx(surface);
  ctx.SetOperator(gfxContext::OPERATOR_CLEAR);
  ctx.Paint();

  gfxImageSurface *retval = nsnull;
  surface.swap(retval);
  return retval;
}

void
nsSVGFilterInstance::LookupImage(const nsAString &aName,
                                 gfxImageSurface **aImage,
                                 nsRect *aRegion,
                                 const ColorModel &aRequiredColorModel)
{
  ImageEntry *entry;

  if (aName.IsEmpty()) {
    entry = mLastImage;
  } else {
    mImageDictionary.Get(aName, &entry);
    if (!entry) {
      entry = mLastImage;
    }
  }

  *aImage = entry->mImage;
  NS_ADDREF(*aImage);
  *aRegion = entry->mRegion;

  if (aRequiredColorModel == entry->mColorModel)
    return;

  // convert image to desired format
  PRUint8 *data = (*aImage)->Data();
  PRInt32 stride = (*aImage)->Stride();

  nsRect r;
  r.IntersectRect(entry->mRegion, mSurfaceRect);
  r -= mSurfaceRect.TopLeft();

  if (entry->mColorModel.mAlphaChannel == ColorModel::PREMULTIPLIED)
    nsSVGUtils::UnPremultiplyImageDataAlpha(data, stride, r);

  if (aRequiredColorModel.mColorSpace != entry->mColorModel.mColorSpace) {
    if (aRequiredColorModel.mColorSpace == ColorModel::LINEAR_RGB)
      nsSVGUtils::ConvertImageDataToLinearRGB(data, stride, r);
    else
      nsSVGUtils::ConvertImageDataFromLinearRGB(data, stride, r);
  }
  if (aRequiredColorModel.mAlphaChannel == ColorModel::PREMULTIPLIED)
    nsSVGUtils::PremultiplyImageDataAlpha(data, stride, r);

  entry->mColorModel = aRequiredColorModel;
}

nsRect
nsSVGFilterInstance::LookupImageRegion(const nsAString &aName)
{
  ImageEntry *entry;

  if (aName.IsEmpty())
    entry = mLastImage;
  else
    mImageDictionary.Get(aName, &entry);

  if (entry)
    return entry->mRegion;

  return nsRect();
}

nsSVGFilterInstance::ColorModel
nsSVGFilterInstance::LookupImageColorModel(const nsAString &aName)
{
  ImageEntry *entry;

  if (aName.IsEmpty())
    entry = mLastImage;
  else
    mImageDictionary.Get(aName, &entry);

  if (entry)
    return entry->mColorModel;

  // We'll reach this point if someone specifies a nonexistent input
  // for a filter, as feDisplacementMap need to find the color model
  // before the filter element calls AcquireSourceImage() which both
  // uses the color model and tells us if the input exists.

  return ColorModel(ColorModel::SRGB, ColorModel::PREMULTIPLIED);
}

void
nsSVGFilterInstance::DefineImage(const nsAString &aName,
                                 gfxImageSurface *aImage,
                                 const nsRect &aRegion,
                                 const ColorModel &aColorModel)
{
  ImageEntry *entry = new ImageEntry(aImage, aRegion, aColorModel);

  if (entry)
    mImageDictionary.Put(aName, entry);

  mLastImage = entry;
}