// Copyright 2017 The Dawn 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.

#ifndef SRC_DAWN_NATIVE_OPENGL_SHADERMODULEGL_H_
#define SRC_DAWN_NATIVE_OPENGL_SHADERMODULEGL_H_

#include <memory>
#include <string>
#include <unordered_map>
#include <vector>

#include "dawn/native/ShaderModule.h"

#include "dawn/native/opengl/opengl_platform.h"

namespace dawn::native::opengl {

class Device;
class PipelineLayout;

std::string GetBindingName(BindGroupIndex group, BindingNumber bindingNumber);

struct BindingLocation {
    BindGroupIndex group;
    BindingNumber binding;
};
bool operator<(const BindingLocation& a, const BindingLocation& b);

struct CombinedSampler {
    BindingLocation samplerLocation;
    BindingLocation textureLocation;
    // OpenGL requires a sampler with texelFetch. If this is true, the developer did not provide
    // one and Dawn should bind a placeholder non-filtering sampler. |samplerLocation| is
    // unused.
    bool usePlaceholderSampler;
    std::string GetName() const;
};
bool operator<(const CombinedSampler& a, const CombinedSampler& b);

using CombinedSamplerInfo = std::vector<CombinedSampler>;

using BindingInfoArrayTable = std::unordered_map<std::string, std::unique_ptr<BindingInfoArray>>;

class ShaderModule final : public ShaderModuleBase {
  public:
    static ResultOrError<Ref<ShaderModule>> Create(Device* device,
                                                   const ShaderModuleDescriptor* descriptor,
                                                   ShaderModuleParseResult* parseResult);

    ResultOrError<std::string> TranslateToGLSL(const char* entryPointName,
                                               SingleShaderStage stage,
                                               CombinedSamplerInfo* combinedSamplers,
                                               const PipelineLayout* layout,
                                               bool* needsPlaceholderSampler) const;

  private:
    ShaderModule(Device* device, const ShaderModuleDescriptor* descriptor);
    ~ShaderModule() override = default;
    MaybeError Initialize(ShaderModuleParseResult* parseResult);
};

}  // namespace dawn::native::opengl

#endif  // SRC_DAWN_NATIVE_OPENGL_SHADERMODULEGL_H_