// Copyright 2020 The Tint Authors.
//
// Licensed under the Apache License, Version 2.0 (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.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

#include "src/ast/storage_texture.h"

#include "src/ast/f32.h"
#include "src/ast/i32.h"
#include "src/ast/u32.h"
#include "src/program_builder.h"

TINT_INSTANTIATE_TYPEINFO(tint::ast::StorageTexture);

namespace tint {
namespace ast {

// Note, these names match the names in the WGSL spec. This behaviour is used
// in the WGSL writer to emit the texture format names.
std::ostream& operator<<(std::ostream& out, ImageFormat format) {
  switch (format) {
    case ImageFormat::kNone:
      out << "none";
      break;
    case ImageFormat::kR8Unorm:
      out << "r8unorm";
      break;
    case ImageFormat::kR8Snorm:
      out << "r8snorm";
      break;
    case ImageFormat::kR8Uint:
      out << "r8uint";
      break;
    case ImageFormat::kR8Sint:
      out << "r8sint";
      break;
    case ImageFormat::kR16Uint:
      out << "r16uint";
      break;
    case ImageFormat::kR16Sint:
      out << "r16sint";
      break;
    case ImageFormat::kR16Float:
      out << "r16float";
      break;
    case ImageFormat::kRg8Unorm:
      out << "rg8unorm";
      break;
    case ImageFormat::kRg8Snorm:
      out << "rg8snorm";
      break;
    case ImageFormat::kRg8Uint:
      out << "rg8uint";
      break;
    case ImageFormat::kRg8Sint:
      out << "rg8sint";
      break;
    case ImageFormat::kR32Uint:
      out << "r32uint";
      break;
    case ImageFormat::kR32Sint:
      out << "r32sint";
      break;
    case ImageFormat::kR32Float:
      out << "r32float";
      break;
    case ImageFormat::kRg16Uint:
      out << "rg16uint";
      break;
    case ImageFormat::kRg16Sint:
      out << "rg16sint";
      break;
    case ImageFormat::kRg16Float:
      out << "rg16float";
      break;
    case ImageFormat::kRgba8Unorm:
      out << "rgba8unorm";
      break;
    case ImageFormat::kRgba8UnormSrgb:
      out << "rgba8unorm_srgb";
      break;
    case ImageFormat::kRgba8Snorm:
      out << "rgba8snorm";
      break;
    case ImageFormat::kRgba8Uint:
      out << "rgba8uint";
      break;
    case ImageFormat::kRgba8Sint:
      out << "rgba8sint";
      break;
    case ImageFormat::kBgra8Unorm:
      out << "bgra8unorm";
      break;
    case ImageFormat::kBgra8UnormSrgb:
      out << "bgra8unorm_srgb";
      break;
    case ImageFormat::kRgb10A2Unorm:
      out << "rgb10a2unorm";
      break;
    case ImageFormat::kRg11B10Float:
      out << "rg11b10float";
      break;
    case ImageFormat::kRg32Uint:
      out << "rg32uint";
      break;
    case ImageFormat::kRg32Sint:
      out << "rg32sint";
      break;
    case ImageFormat::kRg32Float:
      out << "rg32float";
      break;
    case ImageFormat::kRgba16Uint:
      out << "rgba16uint";
      break;
    case ImageFormat::kRgba16Sint:
      out << "rgba16sint";
      break;
    case ImageFormat::kRgba16Float:
      out << "rgba16float";
      break;
    case ImageFormat::kRgba32Uint:
      out << "rgba32uint";
      break;
    case ImageFormat::kRgba32Sint:
      out << "rgba32sint";
      break;
    case ImageFormat::kRgba32Float:
      out << "rgba32float";
      break;
  }
  return out;
}

StorageTexture::StorageTexture(ProgramID program_id,
                               const Source& source,
                               TextureDimension dim,
                               ImageFormat format,
                               Type* subtype,
                               Access access)
    : Base(program_id, source, dim),
      image_format_(format),
      subtype_(subtype),
      access_(access) {}

StorageTexture::StorageTexture(StorageTexture&&) = default;

StorageTexture::~StorageTexture() = default;

std::string StorageTexture::FriendlyName(const SymbolTable&) const {
  std::ostringstream out;
  out << "texture_storage_" << dim() << "<" << image_format_ << ", " << access_
      << ">";
  return out.str();
}

StorageTexture* StorageTexture::Clone(CloneContext* ctx) const {
  // Clone arguments outside of create() call to have deterministic ordering
  auto src = ctx->Clone(source());
  auto* ty = ctx->Clone(type());
  return ctx->dst->create<StorageTexture>(src, dim(), image_format(), ty,
                                          access());
}

Type* StorageTexture::SubtypeFor(ImageFormat format, ProgramBuilder& builder) {
  switch (format) {
    case ImageFormat::kR8Uint:
    case ImageFormat::kR16Uint:
    case ImageFormat::kRg8Uint:
    case ImageFormat::kR32Uint:
    case ImageFormat::kRg16Uint:
    case ImageFormat::kRgba8Uint:
    case ImageFormat::kRg32Uint:
    case ImageFormat::kRgba16Uint:
    case ImageFormat::kRgba32Uint: {
      return builder.create<U32>();
    }

    case ImageFormat::kR8Sint:
    case ImageFormat::kR16Sint:
    case ImageFormat::kRg8Sint:
    case ImageFormat::kR32Sint:
    case ImageFormat::kRg16Sint:
    case ImageFormat::kRgba8Sint:
    case ImageFormat::kRg32Sint:
    case ImageFormat::kRgba16Sint:
    case ImageFormat::kRgba32Sint: {
      return builder.create<I32>();
    }

    case ImageFormat::kR8Unorm:
    case ImageFormat::kRg8Unorm:
    case ImageFormat::kRgba8Unorm:
    case ImageFormat::kRgba8UnormSrgb:
    case ImageFormat::kBgra8Unorm:
    case ImageFormat::kBgra8UnormSrgb:
    case ImageFormat::kRgb10A2Unorm:
    case ImageFormat::kR8Snorm:
    case ImageFormat::kRg8Snorm:
    case ImageFormat::kRgba8Snorm:
    case ImageFormat::kR16Float:
    case ImageFormat::kR32Float:
    case ImageFormat::kRg16Float:
    case ImageFormat::kRg11B10Float:
    case ImageFormat::kRg32Float:
    case ImageFormat::kRgba16Float:
    case ImageFormat::kRgba32Float: {
      return builder.create<F32>();
    }

    case ImageFormat::kNone:
      break;
  }

  return nullptr;
}

}  // namespace ast
}  // namespace tint