// Copyright 2020 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.

#include "dawn/native/BindingInfo.h"

#include "dawn/native/ChainUtils_autogen.h"

namespace dawn::native {

    absl::FormatConvertResult<absl::FormatConversionCharSet::kString> AbslFormatConvert(
        BindingInfoType value,
        const absl::FormatConversionSpec& spec,
        absl::FormatSink* s) {
        switch (value) {
            case BindingInfoType::Buffer:
                s->Append("buffer");
                break;
            case BindingInfoType::Sampler:
                s->Append("sampler");
                break;
            case BindingInfoType::Texture:
                s->Append("texture");
                break;
            case BindingInfoType::StorageTexture:
                s->Append("storageTexture");
                break;
            case BindingInfoType::ExternalTexture:
                s->Append("externalTexture");
                break;
            default:
                UNREACHABLE();
        }
        return {true};
    }

    absl::FormatConvertResult<absl::FormatConversionCharSet::kString> AbslFormatConvert(
        const BindingInfo& value,
        const absl::FormatConversionSpec& spec,
        absl::FormatSink* s) {
        static const auto* const fmt =
            new absl::ParsedFormat<'u', 's', 's', 's'>("{ binding: %u, visibility: %s, %s: %s }");
        switch (value.bindingType) {
            case BindingInfoType::Buffer:
                s->Append(absl::StrFormat(*fmt, static_cast<uint32_t>(value.binding),
                                          value.visibility, value.bindingType, value.buffer));
                break;
            case BindingInfoType::Sampler:
                s->Append(absl::StrFormat(*fmt, static_cast<uint32_t>(value.binding),
                                          value.visibility, value.bindingType, value.sampler));
                break;
            case BindingInfoType::Texture:
                s->Append(absl::StrFormat(*fmt, static_cast<uint32_t>(value.binding),
                                          value.visibility, value.bindingType, value.texture));
                break;
            case BindingInfoType::StorageTexture:
                s->Append(absl::StrFormat(*fmt, static_cast<uint32_t>(value.binding),
                                          value.visibility, value.bindingType,
                                          value.storageTexture));
                break;
            case BindingInfoType::ExternalTexture:
                break;
        }
        return {true};
    }

    void IncrementBindingCounts(BindingCounts* bindingCounts, const BindGroupLayoutEntry& entry) {
        bindingCounts->totalCount += 1;

        uint32_t PerStageBindingCounts::*perStageBindingCountMember = nullptr;

        if (entry.buffer.type != wgpu::BufferBindingType::Undefined) {
            ++bindingCounts->bufferCount;
            const BufferBindingLayout& buffer = entry.buffer;

            if (buffer.minBindingSize == 0) {
                ++bindingCounts->unverifiedBufferCount;
            }

            switch (buffer.type) {
                case wgpu::BufferBindingType::Uniform:
                    if (buffer.hasDynamicOffset) {
                        ++bindingCounts->dynamicUniformBufferCount;
                    }
                    perStageBindingCountMember = &PerStageBindingCounts::uniformBufferCount;
                    break;

                case wgpu::BufferBindingType::Storage:
                case kInternalStorageBufferBinding:
                case wgpu::BufferBindingType::ReadOnlyStorage:
                    if (buffer.hasDynamicOffset) {
                        ++bindingCounts->dynamicStorageBufferCount;
                    }
                    perStageBindingCountMember = &PerStageBindingCounts::storageBufferCount;
                    break;

                case wgpu::BufferBindingType::Undefined:
                    // Can't get here due to the enclosing if statement.
                    UNREACHABLE();
                    break;
            }
        } else if (entry.sampler.type != wgpu::SamplerBindingType::Undefined) {
            perStageBindingCountMember = &PerStageBindingCounts::samplerCount;
        } else if (entry.texture.sampleType != wgpu::TextureSampleType::Undefined) {
            perStageBindingCountMember = &PerStageBindingCounts::sampledTextureCount;
        } else if (entry.storageTexture.access != wgpu::StorageTextureAccess::Undefined) {
            perStageBindingCountMember = &PerStageBindingCounts::storageTextureCount;
        } else {
            const ExternalTextureBindingLayout* externalTextureBindingLayout;
            FindInChain(entry.nextInChain, &externalTextureBindingLayout);
            if (externalTextureBindingLayout != nullptr) {
                perStageBindingCountMember = &PerStageBindingCounts::externalTextureCount;
            }
        }

        ASSERT(perStageBindingCountMember != nullptr);
        for (SingleShaderStage stage : IterateStages(entry.visibility)) {
            ++(bindingCounts->perStage[stage].*perStageBindingCountMember);
        }
    }

    void AccumulateBindingCounts(BindingCounts* bindingCounts, const BindingCounts& rhs) {
        bindingCounts->totalCount += rhs.totalCount;
        bindingCounts->bufferCount += rhs.bufferCount;
        bindingCounts->unverifiedBufferCount += rhs.unverifiedBufferCount;
        bindingCounts->dynamicUniformBufferCount += rhs.dynamicUniformBufferCount;
        bindingCounts->dynamicStorageBufferCount += rhs.dynamicStorageBufferCount;

        for (SingleShaderStage stage : IterateStages(kAllStages)) {
            bindingCounts->perStage[stage].sampledTextureCount +=
                rhs.perStage[stage].sampledTextureCount;
            bindingCounts->perStage[stage].samplerCount += rhs.perStage[stage].samplerCount;
            bindingCounts->perStage[stage].storageBufferCount +=
                rhs.perStage[stage].storageBufferCount;
            bindingCounts->perStage[stage].storageTextureCount +=
                rhs.perStage[stage].storageTextureCount;
            bindingCounts->perStage[stage].uniformBufferCount +=
                rhs.perStage[stage].uniformBufferCount;
            bindingCounts->perStage[stage].externalTextureCount +=
                rhs.perStage[stage].externalTextureCount;
        }
    }

    MaybeError ValidateBindingCounts(const BindingCounts& bindingCounts) {
        DAWN_INVALID_IF(
            bindingCounts.dynamicUniformBufferCount > kMaxDynamicUniformBuffersPerPipelineLayout,
            "The number of dynamic uniform buffers (%u) exceeds the maximum per-pipeline-layout "
            "limit (%u).",
            bindingCounts.dynamicUniformBufferCount, kMaxDynamicUniformBuffersPerPipelineLayout);

        DAWN_INVALID_IF(
            bindingCounts.dynamicStorageBufferCount > kMaxDynamicStorageBuffersPerPipelineLayout,
            "The number of dynamic storage buffers (%u) exceeds the maximum per-pipeline-layout "
            "limit (%u).",
            bindingCounts.dynamicStorageBufferCount, kMaxDynamicStorageBuffersPerPipelineLayout);

        for (SingleShaderStage stage : IterateStages(kAllStages)) {
            DAWN_INVALID_IF(
                bindingCounts.perStage[stage].sampledTextureCount >
                    kMaxSampledTexturesPerShaderStage,
                "The number of sampled textures (%u) in the %s stage exceeds the maximum "
                "per-stage limit (%u).",
                bindingCounts.perStage[stage].sampledTextureCount, stage,
                kMaxSampledTexturesPerShaderStage);

            // The per-stage number of external textures is bound by the maximum sampled textures
            // per stage.
            DAWN_INVALID_IF(
                bindingCounts.perStage[stage].externalTextureCount >
                    kMaxSampledTexturesPerShaderStage / kSampledTexturesPerExternalTexture,
                "The number of external textures (%u) in the %s stage exceeds the maximum "
                "per-stage limit (%u).",
                bindingCounts.perStage[stage].externalTextureCount, stage,
                kMaxSampledTexturesPerShaderStage / kSampledTexturesPerExternalTexture);

            DAWN_INVALID_IF(
                bindingCounts.perStage[stage].sampledTextureCount +
                        (bindingCounts.perStage[stage].externalTextureCount *
                         kSampledTexturesPerExternalTexture) >
                    kMaxSampledTexturesPerShaderStage,
                "The combination of sampled textures (%u) and external textures (%u) in the %s "
                "stage exceeds the maximum per-stage limit (%u).",
                bindingCounts.perStage[stage].sampledTextureCount,
                bindingCounts.perStage[stage].externalTextureCount, stage,
                kMaxSampledTexturesPerShaderStage);

            DAWN_INVALID_IF(
                bindingCounts.perStage[stage].samplerCount > kMaxSamplersPerShaderStage,
                "The number of samplers (%u) in the %s stage exceeds the maximum per-stage limit "
                "(%u).",
                bindingCounts.perStage[stage].samplerCount, stage, kMaxSamplersPerShaderStage);

            DAWN_INVALID_IF(
                bindingCounts.perStage[stage].samplerCount +
                        (bindingCounts.perStage[stage].externalTextureCount *
                         kSamplersPerExternalTexture) >
                    kMaxSamplersPerShaderStage,
                "The combination of samplers (%u) and external textures (%u) in the %s stage "
                "exceeds the maximum per-stage limit (%u).",
                bindingCounts.perStage[stage].samplerCount,
                bindingCounts.perStage[stage].externalTextureCount, stage,
                kMaxSamplersPerShaderStage);

            DAWN_INVALID_IF(
                bindingCounts.perStage[stage].storageBufferCount > kMaxStorageBuffersPerShaderStage,
                "The number of storage buffers (%u) in the %s stage exceeds the maximum per-stage "
                "limit (%u).",
                bindingCounts.perStage[stage].storageBufferCount, stage,
                kMaxStorageBuffersPerShaderStage);

            DAWN_INVALID_IF(
                bindingCounts.perStage[stage].storageTextureCount >
                    kMaxStorageTexturesPerShaderStage,
                "The number of storage textures (%u) in the %s stage exceeds the maximum per-stage "
                "limit (%u).",
                bindingCounts.perStage[stage].storageTextureCount, stage,
                kMaxStorageTexturesPerShaderStage);

            DAWN_INVALID_IF(
                bindingCounts.perStage[stage].uniformBufferCount > kMaxUniformBuffersPerShaderStage,
                "The number of uniform buffers (%u) in the %s stage exceeds the maximum per-stage "
                "limit (%u).",
                bindingCounts.perStage[stage].uniformBufferCount, stage,
                kMaxUniformBuffersPerShaderStage);

            DAWN_INVALID_IF(
                bindingCounts.perStage[stage].uniformBufferCount +
                        (bindingCounts.perStage[stage].externalTextureCount *
                         kUniformsPerExternalTexture) >
                    kMaxUniformBuffersPerShaderStage,
                "The combination of uniform buffers (%u) and external textures (%u) in the %s "
                "stage exceeds the maximum per-stage limit (%u).",
                bindingCounts.perStage[stage].uniformBufferCount,
                bindingCounts.perStage[stage].externalTextureCount, stage,
                kMaxUniformBuffersPerShaderStage);
        }

        return {};
    }

}  // namespace dawn::native