/* -*- Mode: C++; tab-width: 4; 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 "Texture.h"

#include "ipc/WebGPUChild.h"
#include "mozilla/webgpu/ffi/wgpu.h"
#include "mozilla/webgpu/CanvasContext.h"
#include "mozilla/dom/WebGPUBinding.h"
#include "mozilla/webgpu/WebGPUTypes.h"
#include "TextureView.h"
#include "Utility.h"

namespace mozilla::webgpu {

GPU_IMPL_CYCLE_COLLECTION(Texture, mParent)
GPU_IMPL_JS_WRAP(Texture)

static Maybe<uint8_t> GetBytesPerBlockSingleAspect(
    dom::GPUTextureFormat aFormat) {
  auto format = ConvertTextureFormat(aFormat);
  uint32_t bytes = ffi::wgpu_texture_format_block_size_single_aspect(format);
  if (bytes == 0) {
    // The above function returns zero if the texture has multiple aspects like
    // depth and stencil.
    return Nothing();
  }

  return Some((uint8_t)bytes);
}

Texture::Texture(Device* const aParent, RawId aId,
                 const dom::GPUTextureDescriptor& aDesc)
    : ChildOf(aParent),
      mId(aId),
      mFormat(aDesc.mFormat),
      mBytesPerBlock(GetBytesPerBlockSingleAspect(aDesc.mFormat)),
      mSize(ConvertExtent(aDesc.mSize)),
      mMipLevelCount(aDesc.mMipLevelCount),
      mSampleCount(aDesc.mSampleCount),
      mDimension(aDesc.mDimension),
      mUsage(aDesc.mUsage) {
  MOZ_RELEASE_ASSERT(aId);
}

void Texture::Cleanup() {
  if (!mValid) {
    return;
  }
  mValid = false;

  auto bridge = mParent->GetBridge();
  if (!bridge) {
    return;
  }

  if (bridge->CanSend()) {
    bridge->SendTextureDrop(mId);
  }

  wgpu_client_free_texture_id(bridge->GetClient(), mId);
}

Texture::~Texture() { Cleanup(); }

already_AddRefed<TextureView> Texture::CreateView(
    const dom::GPUTextureViewDescriptor& aDesc) {
  auto bridge = mParent->GetBridge();

  ffi::WGPUTextureViewDescriptor desc = {};

  webgpu::StringHelper label(aDesc.mLabel);
  desc.label = label.Get();

  ffi::WGPUTextureFormat format = {ffi::WGPUTextureFormat_Sentinel};
  if (aDesc.mFormat.WasPassed()) {
    format = ConvertTextureFormat(aDesc.mFormat.Value());
    desc.format = &format;
  }
  ffi::WGPUTextureViewDimension dimension =
      ffi::WGPUTextureViewDimension_Sentinel;
  if (aDesc.mDimension.WasPassed()) {
    dimension = ffi::WGPUTextureViewDimension(aDesc.mDimension.Value());
    desc.dimension = &dimension;
  }

  // Ideally we'd just do something like "aDesc.mMipLevelCount.ptrOr(nullptr)"
  // but dom::Optional does not seem to have very many nice things.
  uint32_t mipCount =
      aDesc.mMipLevelCount.WasPassed() ? aDesc.mMipLevelCount.Value() : 0;
  uint32_t layerCount =
      aDesc.mArrayLayerCount.WasPassed() ? aDesc.mArrayLayerCount.Value() : 0;

  desc.aspect = ffi::WGPUTextureAspect(aDesc.mAspect);
  desc.base_mip_level = aDesc.mBaseMipLevel;
  desc.mip_level_count = aDesc.mMipLevelCount.WasPassed() ? &mipCount : nullptr;
  desc.base_array_layer = aDesc.mBaseArrayLayer;
  desc.array_layer_count =
      aDesc.mArrayLayerCount.WasPassed() ? &layerCount : nullptr;

  ipc::ByteBuf bb;
  RawId id = ffi::wgpu_client_create_texture_view(bridge->GetClient(), mId,
                                                  &desc, ToFFI(&bb));
  if (bridge->CanSend()) {
    bridge->SendTextureAction(mId, mParent->mId, std::move(bb));
  }

  RefPtr<TextureView> view = new TextureView(this, id);
  return view.forget();
}

void Texture::Destroy() {
  auto bridge = mParent->GetBridge();
  if (bridge && bridge->CanSend()) {
    bridge->SendTextureDestroy(mId, mParent->GetId());
  }
}

}  // namespace mozilla::webgpu