/* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 2 -*-
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#include "mozilla/layers/PLayerTransaction.h"

// This must occur *after* layers/PLayerTransaction.h to avoid
// typedefs conflicts.
#include "mozilla/ArrayUtils.h"

#include "ThebesLayerD3D10.h"
#include "gfxPlatform.h"

#include "gfxWindowsPlatform.h"
#ifdef CAIRO_HAS_D2D_SURFACE
#include "gfxD2DSurface.h"
#endif

#include "../d3d9/Nv3DVUtils.h"
#include "gfxTeeSurface.h"
#include "gfxUtils.h"
#include "ReadbackLayer.h"
#include "ReadbackProcessor.h"

#include "mozilla/Preferences.h"
#include "mozilla/gfx/2D.h"

using namespace mozilla::gfx;

namespace mozilla {
namespace layers {

ThebesLayerD3D10::ThebesLayerD3D10(LayerManagerD3D10 *aManager)
  : ThebesLayer(aManager, nullptr)
  , LayerD3D10(aManager)
  , mCurrentSurfaceMode(SurfaceMode::SURFACE_OPAQUE)
{
  mImplData = static_cast<LayerD3D10*>(this);
}

ThebesLayerD3D10::~ThebesLayerD3D10()
{
}

void
ThebesLayerD3D10::InvalidateRegion(const nsIntRegion &aRegion)
{
  mInvalidRegion.Or(mInvalidRegion, aRegion);
  mInvalidRegion.SimplifyOutward(10);
  mValidRegion.Sub(mValidRegion, mInvalidRegion);
}

void ThebesLayerD3D10::CopyRegion(ID3D10Texture2D* aSrc, const nsIntPoint &aSrcOffset,
                                  ID3D10Texture2D* aDest, const nsIntPoint &aDestOffset,
                                  const nsIntRegion &aCopyRegion, nsIntRegion* aValidRegion)
{
  nsIntRegion retainedRegion;
  nsIntRegionRectIterator iter(aCopyRegion);
  const nsIntRect *r;
  while ((r = iter.Next())) {
    // Calculate the retained rectangle's position on the old and the new
    // surface.
    D3D10_BOX box;
    box.left = r->x - aSrcOffset.x;
    box.top = r->y - aSrcOffset.y;
    box.right = box.left + r->width;
    box.bottom = box.top + r->height;
    box.back = 1;
    box.front = 0;

    device()->CopySubresourceRegion(aDest, 0,
                                    r->x - aDestOffset.x,
                                    r->y - aDestOffset.y,
                                    0,
                                    aSrc, 0,
                                    &box);

    retainedRegion.Or(retainedRegion, *r);
  }

  // Areas which were valid and were retained are still valid
  aValidRegion->And(*aValidRegion, retainedRegion);  
}

void
ThebesLayerD3D10::RenderLayer()
{
  if (!mTexture) {
    return;
  }

  SetEffectTransformAndOpacity();

  ID3D10EffectTechnique *technique;
  switch (mCurrentSurfaceMode) {
  case SurfaceMode::SURFACE_COMPONENT_ALPHA:
    technique = SelectShader(SHADER_COMPONENT_ALPHA | LoadMaskTexture());
    break;
  case SurfaceMode::SURFACE_OPAQUE:
    technique = SelectShader(SHADER_RGB | SHADER_PREMUL | LoadMaskTexture());
    break;
  case SurfaceMode::SURFACE_SINGLE_CHANNEL_ALPHA:
    technique = SelectShader(SHADER_RGBA | SHADER_PREMUL | LoadMaskTexture());
    break;
  default:
    NS_ERROR("Unknown mode");
    return;
  }

  nsIntRegionRectIterator iter(mVisibleRegion);

  const nsIntRect *iterRect;
  if (mSRView) {
    effect()->GetVariableByName("tRGB")->AsShaderResource()->SetResource(mSRView);
  }
  if (mSRViewOnWhite) {
    effect()->GetVariableByName("tRGBWhite")->AsShaderResource()->SetResource(mSRViewOnWhite);
  }

  while ((iterRect = iter.Next())) {
    effect()->GetVariableByName("vLayerQuad")->AsVector()->SetFloatVector(
      ShaderConstantRectD3D10(
        (float)iterRect->x,
        (float)iterRect->y,
        (float)iterRect->width,
        (float)iterRect->height)
      );

    effect()->GetVariableByName("vTextureCoords")->AsVector()->SetFloatVector(
      ShaderConstantRectD3D10(
        (float)(iterRect->x - mTextureRect.x) / (float)mTextureRect.width,
        (float)(iterRect->y - mTextureRect.y) / (float)mTextureRect.height,
        (float)iterRect->width / (float)mTextureRect.width,
        (float)iterRect->height / (float)mTextureRect.height)
      );

    technique->GetPassByIndex(0)->Apply(0);
    device()->Draw(4, 0);
  }

  // Set back to default.
  effect()->GetVariableByName("vTextureCoords")->AsVector()->
    SetFloatVector(ShaderConstantRectD3D10(0, 0, 1.0f, 1.0f));
}

void
ThebesLayerD3D10::Validate(ReadbackProcessor *aReadback)
{
  if (mVisibleRegion.IsEmpty()) {
    return;
  }

  if (FAILED(gfxWindowsPlatform::GetPlatform()->GetD3D10Device()->GetDeviceRemovedReason())) {
    // Device removed, this will be discovered on the next rendering pass.
    // Do no validate.
    return;
  }

  nsIntRect newTextureRect = mVisibleRegion.GetBounds();

  SurfaceMode mode = GetSurfaceMode();
  if (mode == SurfaceMode::SURFACE_COMPONENT_ALPHA &&
      (!mParent || !mParent->SupportsComponentAlphaChildren())) {
    mode = SurfaceMode::SURFACE_SINGLE_CHANNEL_ALPHA;
  }
  // If we have a transform that requires resampling of our texture, then
  // we need to make sure we don't sample pixels that haven't been drawn.
  // We clamp sample coordinates to the texture rect, but when the visible region
  // doesn't fill the entire texture rect we need to make sure we draw all the
  // pixels in the texture rect anyway in case they get sampled.
  nsIntRegion neededRegion = mVisibleRegion;
  if (!neededRegion.GetBounds().IsEqualInterior(newTextureRect) ||
      neededRegion.GetNumRects() > 1) {
    if (MayResample()) {
      neededRegion = newTextureRect;
      if (mode == SurfaceMode::SURFACE_OPAQUE) {
        // We're going to paint outside the visible region, but layout hasn't
        // promised that it will paint opaquely there, so we'll have to
        // treat this layer as transparent.
        mode = SurfaceMode::SURFACE_SINGLE_CHANNEL_ALPHA;
      }
    }
  }
  mCurrentSurfaceMode = mode;

  VerifyContentType(mode);

  nsTArray<ReadbackProcessor::Update> readbackUpdates;
  nsIntRegion readbackRegion;
  if (aReadback && UsedForReadback()) {
    aReadback->GetThebesLayerUpdates(this, &readbackUpdates, &readbackRegion);
  }

  if (mTexture) {
    if (!mTextureRect.IsEqualInterior(newTextureRect)) {
      nsRefPtr<ID3D10Texture2D> oldTexture = mTexture;
      mTexture = nullptr;
      nsRefPtr<ID3D10Texture2D> oldTextureOnWhite = mTextureOnWhite;
      mTextureOnWhite = nullptr;

      nsIntRegion retainRegion = mTextureRect;
      // Old visible region will become the region that is covered by both the
      // old and the new visible region.
      retainRegion.And(retainRegion, mVisibleRegion);
      // No point in retaining parts which were not valid.
      retainRegion.And(retainRegion, mValidRegion);

      CreateNewTextures(gfx::IntSize(newTextureRect.width, newTextureRect.height), mode);

      nsIntRect largeRect = retainRegion.GetLargestRectangle();

      // If we had no hardware texture before, or have no retained area larger than
      // the retention threshold, we're not retaining and are done here.
      // If our texture creation failed this can mean a device reset is pending
      // and we should silently ignore the failure. In the future when device
      // failures are properly handled we should test for the type of failure
      // and gracefully handle different failures. See bug 569081.
      if (!oldTexture || !mTexture) {
        mValidRegion.SetEmpty();
      } else {
        CopyRegion(oldTexture, mTextureRect.TopLeft(),
                   mTexture, newTextureRect.TopLeft(),
                   retainRegion, &mValidRegion);
        if (oldTextureOnWhite) {
          CopyRegion(oldTextureOnWhite, mTextureRect.TopLeft(),
                     mTextureOnWhite, newTextureRect.TopLeft(),
                     retainRegion, &mValidRegion);
        }
      }
    }
  }
  mTextureRect = newTextureRect;

  if (!mTexture || (mode == SurfaceMode::SURFACE_COMPONENT_ALPHA && !mTextureOnWhite)) {
    CreateNewTextures(gfx::IntSize(newTextureRect.width, newTextureRect.height), mode);
    mValidRegion.SetEmpty();
  }

  nsIntRegion drawRegion;
  drawRegion.Sub(neededRegion, mValidRegion);

  if (!drawRegion.IsEmpty()) {
    LayerManagerD3D10::CallbackInfo cbInfo = mD3DManager->GetCallbackInfo();
    if (!cbInfo.Callback) {
      NS_ERROR("D3D10 should never need to update ThebesLayers in an empty transaction");
      return;
    }

    DrawRegion(drawRegion, mode);

    if (readbackUpdates.Length() > 0) {
      CD3D10_TEXTURE2D_DESC desc(DXGI_FORMAT_B8G8R8A8_UNORM,
                                 newTextureRect.width, newTextureRect.height,
                                 1, 1, 0, D3D10_USAGE_STAGING,
                                 D3D10_CPU_ACCESS_READ);

      nsRefPtr<ID3D10Texture2D> readbackTexture;
      HRESULT hr = device()->CreateTexture2D(&desc, nullptr, getter_AddRefs(readbackTexture));
      if (FAILED(hr)) {
        LayerManagerD3D10::ReportFailure(NS_LITERAL_CSTRING("ThebesLayerD3D10::Validate(): Failed to create texture"),
                                         hr);
        return;
      }

      device()->CopyResource(readbackTexture, mTexture);

      for (uint32_t i = 0; i < readbackUpdates.Length(); i++) {
        mD3DManager->readbackManager()->PostTask(readbackTexture,
                                                 &readbackUpdates[i],
                                                 gfxPoint(newTextureRect.x, newTextureRect.y));
      }
    }

    mValidRegion = neededRegion;
  }
}

void
ThebesLayerD3D10::LayerManagerDestroyed()
{
  mD3DManager = nullptr;
}

Layer*
ThebesLayerD3D10::GetLayer()
{
  return this;
}

void
ThebesLayerD3D10::VerifyContentType(SurfaceMode aMode)
{
  if (mD2DSurface) {
    gfxContentType type = aMode != SurfaceMode::SURFACE_SINGLE_CHANNEL_ALPHA ?
      gfxContentType::COLOR : gfxContentType::COLOR_ALPHA;

    if (type != mD2DSurface->GetContentType()) {  
      mD2DSurface = new gfxD2DSurface(mTexture, type);

      if (!mD2DSurface || mD2DSurface->CairoStatus()) {
        NS_WARNING("Failed to create surface for ThebesLayerD3D10.");
        mD2DSurface = nullptr;
        return;
      }

      mValidRegion.SetEmpty();
    }
  } else if (mDrawTarget) {
    SurfaceFormat format = aMode != SurfaceMode::SURFACE_SINGLE_CHANNEL_ALPHA ?
      SurfaceFormat::B8G8R8X8 : SurfaceFormat::B8G8R8A8;

    if (format != mDrawTarget->GetFormat()) {
      mDrawTarget = Factory::CreateDrawTargetForD3D10Texture(mTexture, format);

      if (!mDrawTarget) {
        NS_WARNING("Failed to create drawtarget for ThebesLayerD3D10.");
        return;
      }

      mValidRegion.SetEmpty();
    }
  }    

  if (aMode != SurfaceMode::SURFACE_COMPONENT_ALPHA && mTextureOnWhite) {
    // If we've transitioned away from component alpha, we can delete those resources.
    mD2DSurfaceOnWhite = nullptr;
    mSRViewOnWhite = nullptr;
    mTextureOnWhite = nullptr;
    mValidRegion.SetEmpty();
  }
}

void
ThebesLayerD3D10::FillTexturesBlackWhite(const nsIntRegion& aRegion, const nsIntPoint& aOffset)
{
  if (mTexture && mTextureOnWhite) {
    // It would be more optimal to draw the actual geometry, but more code
    // and probably not worth the win here as this will often be a single
    // rect.
    nsRefPtr<ID3D10RenderTargetView> oldRT;
    device()->OMGetRenderTargets(1, getter_AddRefs(oldRT), nullptr);

    nsRefPtr<ID3D10RenderTargetView> viewBlack;
    nsRefPtr<ID3D10RenderTargetView> viewWhite;
    device()->CreateRenderTargetView(mTexture, nullptr, getter_AddRefs(viewBlack));
    device()->CreateRenderTargetView(mTextureOnWhite, nullptr, getter_AddRefs(viewWhite));

    D3D10_RECT oldScissor;
    UINT numRects = 1;
    device()->RSGetScissorRects(&numRects, &oldScissor);

    D3D10_TEXTURE2D_DESC desc;
    mTexture->GetDesc(&desc);

    D3D10_RECT scissor = { 0, 0, desc.Width, desc.Height };
    device()->RSSetScissorRects(1, &scissor);

    mD3DManager->SetupInputAssembler();
    nsIntSize oldVP = mD3DManager->GetViewport();

    mD3DManager->SetViewport(nsIntSize(desc.Width, desc.Height));

    ID3D10RenderTargetView *views[2] = { viewBlack, viewWhite };
    device()->OMSetRenderTargets(2, views, nullptr);

    gfx3DMatrix transform;
    transform.Translate(gfxPoint3D(-aOffset.x, -aOffset.y, 0));
    void* raw = &const_cast<gfx3DMatrix&>(transform)._11;
    effect()->GetVariableByName("mLayerTransform")->SetRawValue(raw, 0, 64);

    ID3D10EffectTechnique *technique =
      effect()->GetTechniqueByName("PrepareAlphaExtractionTextures");

    nsIntRegionRectIterator iter(aRegion);

    const nsIntRect *iterRect;
    while ((iterRect = iter.Next())) {
      effect()->GetVariableByName("vLayerQuad")->AsVector()->SetFloatVector(
        ShaderConstantRectD3D10(
          (float)iterRect->x,
          (float)iterRect->y,
          (float)iterRect->width,
          (float)iterRect->height)
        );

      technique->GetPassByIndex(0)->Apply(0);
      device()->Draw(4, 0);
    }

    views[0] = oldRT;
    device()->OMSetRenderTargets(1, views, nullptr);
    mD3DManager->SetViewport(oldVP);
    device()->RSSetScissorRects(1, &oldScissor);
  }
}

void
ThebesLayerD3D10::DrawRegion(nsIntRegion &aRegion, SurfaceMode aMode)
{
  nsIntRect visibleRect = mVisibleRegion.GetBounds();

  if (!mD2DSurface && !mDrawTarget) {
    return;
  }

  nsRefPtr<gfxASurface> destinationSurface;
  
  if (aMode == SurfaceMode::SURFACE_COMPONENT_ALPHA) {
    FillTexturesBlackWhite(aRegion, visibleRect.TopLeft());
  } else {
    destinationSurface = mD2DSurface;
  }

  aRegion.SimplifyOutwardByArea(100 * 100);

  MOZ_ASSERT(mDrawTarget);
  nsRefPtr<gfxContext> context = new gfxContext(mDrawTarget);

  context->Translate(gfxPoint(-visibleRect.x, -visibleRect.y));
  if (aMode == SurfaceMode::SURFACE_SINGLE_CHANNEL_ALPHA) {
    nsIntRegionRectIterator iter(aRegion);
    const nsIntRect *iterRect;
    while ((iterRect = iter.Next())) {
      mDrawTarget->ClearRect(Rect(iterRect->x, iterRect->y, iterRect->width, iterRect->height));
    }
  }

  mDrawTarget->SetPermitSubpixelAA(!(mContentFlags & CONTENT_COMPONENT_ALPHA));

  LayerManagerD3D10::CallbackInfo cbInfo = mD3DManager->GetCallbackInfo();
  cbInfo.Callback(this, context, aRegion, DrawRegionClip::DRAW, nsIntRegion(), cbInfo.CallbackData);
}

void
ThebesLayerD3D10::CreateNewTextures(const gfx::IntSize &aSize, SurfaceMode aMode)
{
  if (aSize.width == 0 || aSize.height == 0) {
    // Nothing to do.
    return;
  }

  CD3D10_TEXTURE2D_DESC desc(DXGI_FORMAT_B8G8R8A8_UNORM, aSize.width, aSize.height, 1, 1);
  desc.BindFlags = D3D10_BIND_RENDER_TARGET | D3D10_BIND_SHADER_RESOURCE;
  desc.MiscFlags = D3D10_RESOURCE_MISC_GDI_COMPATIBLE;
  HRESULT hr;

  if (!mTexture) {
    hr = device()->CreateTexture2D(&desc, nullptr, getter_AddRefs(mTexture));

    if (FAILED(hr)) {
      NS_WARNING("Failed to create new texture for ThebesLayerD3D10!");
      return;
    }

    hr = device()->CreateShaderResourceView(mTexture, nullptr, getter_AddRefs(mSRView));

    if (FAILED(hr)) {
      NS_WARNING("Failed to create shader resource view for ThebesLayerD3D10.");
    }

    mDrawTarget = nullptr;
  }

  if (aMode == SurfaceMode::SURFACE_COMPONENT_ALPHA && !mTextureOnWhite) {
    hr = device()->CreateTexture2D(&desc, nullptr, getter_AddRefs(mTextureOnWhite));

    if (FAILED(hr)) {
      NS_WARNING("Failed to create new texture for ThebesLayerD3D10!");
      return;
    }

    hr = device()->CreateShaderResourceView(mTextureOnWhite, nullptr, getter_AddRefs(mSRViewOnWhite));

    if (FAILED(hr)) {
      NS_WARNING("Failed to create shader resource view for ThebesLayerD3D10.");
    }

    mDrawTarget = nullptr;
  }

  if (!mDrawTarget) {
    if (aMode == SurfaceMode::SURFACE_COMPONENT_ALPHA) {
      mDrawTarget = Factory::CreateDualDrawTargetForD3D10Textures(mTexture, mTextureOnWhite, SurfaceFormat::B8G8R8X8);
    } else {
      mDrawTarget = Factory::CreateDrawTargetForD3D10Texture(mTexture, aMode != SurfaceMode::SURFACE_SINGLE_CHANNEL_ALPHA ?
        SurfaceFormat::B8G8R8X8 : SurfaceFormat::B8G8R8A8);
    }

    if (!mDrawTarget) {
      NS_WARNING("Failed to create DrawTarget for ThebesLayerD3D10.");
      mDrawTarget = nullptr;
      return;
    }
  }
}

} /* namespace layers */
} /* namespace mozilla */