// Copyright 2018 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/ProgrammableEncoder.h"

#include "dawn/common/BitSetIterator.h"
#include "dawn/common/ityp_array.h"
#include "dawn/native/BindGroup.h"
#include "dawn/native/Buffer.h"
#include "dawn/native/CommandBuffer.h"
#include "dawn/native/Commands.h"
#include "dawn/native/Device.h"
#include "dawn/native/ObjectType_autogen.h"
#include "dawn/native/ValidationUtils_autogen.h"

#include <cstring>

namespace dawn::native {

    ProgrammableEncoder::ProgrammableEncoder(DeviceBase* device,
                                             const char* label,
                                             EncodingContext* encodingContext)
        : ApiObjectBase(device, label),
          mEncodingContext(encodingContext),
          mValidationEnabled(device->IsValidationEnabled()) {
    }

    ProgrammableEncoder::ProgrammableEncoder(DeviceBase* device,
                                             EncodingContext* encodingContext,
                                             ErrorTag errorTag)
        : ApiObjectBase(device, errorTag),
          mEncodingContext(encodingContext),
          mValidationEnabled(device->IsValidationEnabled()) {
    }

    bool ProgrammableEncoder::IsValidationEnabled() const {
        return mValidationEnabled;
    }

    MaybeError ProgrammableEncoder::ValidateProgrammableEncoderEnd() const {
        DAWN_INVALID_IF(mDebugGroupStackSize != 0,
                        "PushDebugGroup called %u time(s) without a corresponding PopDebugGroup.",
                        mDebugGroupStackSize);
        return {};
    }

    void ProgrammableEncoder::APIInsertDebugMarker(const char* groupLabel) {
        mEncodingContext->TryEncode(
            this,
            [&](CommandAllocator* allocator) -> MaybeError {
                InsertDebugMarkerCmd* cmd =
                    allocator->Allocate<InsertDebugMarkerCmd>(Command::InsertDebugMarker);
                cmd->length = strlen(groupLabel);

                char* label = allocator->AllocateData<char>(cmd->length + 1);
                memcpy(label, groupLabel, cmd->length + 1);

                return {};
            },
            "encoding %s.InsertDebugMarker(\"%s\").", this, groupLabel);
    }

    void ProgrammableEncoder::APIPopDebugGroup() {
        mEncodingContext->TryEncode(
            this,
            [&](CommandAllocator* allocator) -> MaybeError {
                if (IsValidationEnabled()) {
                    DAWN_INVALID_IF(
                        mDebugGroupStackSize == 0,
                        "PopDebugGroup called when no debug groups are currently pushed.");
                }
                allocator->Allocate<PopDebugGroupCmd>(Command::PopDebugGroup);
                mDebugGroupStackSize--;
                mEncodingContext->PopDebugGroupLabel();

                return {};
            },
            "encoding %s.PopDebugGroup().", this);
    }

    void ProgrammableEncoder::APIPushDebugGroup(const char* groupLabel) {
        mEncodingContext->TryEncode(
            this,
            [&](CommandAllocator* allocator) -> MaybeError {
                PushDebugGroupCmd* cmd =
                    allocator->Allocate<PushDebugGroupCmd>(Command::PushDebugGroup);
                cmd->length = strlen(groupLabel);

                char* label = allocator->AllocateData<char>(cmd->length + 1);
                memcpy(label, groupLabel, cmd->length + 1);

                mDebugGroupStackSize++;
                mEncodingContext->PushDebugGroupLabel(groupLabel);

                return {};
            },
            "encoding %s.PushDebugGroup(\"%s\").", this, groupLabel);
    }

    MaybeError ProgrammableEncoder::ValidateSetBindGroup(BindGroupIndex index,
                                                         BindGroupBase* group,
                                                         uint32_t dynamicOffsetCountIn,
                                                         const uint32_t* dynamicOffsetsIn) const {
        DAWN_TRY(GetDevice()->ValidateObject(group));

        DAWN_INVALID_IF(index >= kMaxBindGroupsTyped,
                        "Bind group index (%u) exceeds the maximum (%u).",
                        static_cast<uint32_t>(index), kMaxBindGroups);

        ityp::span<BindingIndex, const uint32_t> dynamicOffsets(dynamicOffsetsIn,
                                                                BindingIndex(dynamicOffsetCountIn));

        // Dynamic offsets count must match the number required by the layout perfectly.
        const BindGroupLayoutBase* layout = group->GetLayout();
        DAWN_INVALID_IF(
            layout->GetDynamicBufferCount() != dynamicOffsets.size(),
            "The number of dynamic offsets (%u) does not match the number of dynamic buffers (%u) "
            "in %s.",
            static_cast<uint32_t>(dynamicOffsets.size()),
            static_cast<uint32_t>(layout->GetDynamicBufferCount()), layout);

        for (BindingIndex i{0}; i < dynamicOffsets.size(); ++i) {
            const BindingInfo& bindingInfo = layout->GetBindingInfo(i);

            // BGL creation sorts bindings such that the dynamic buffer bindings are first.
            // ASSERT that this true.
            ASSERT(bindingInfo.bindingType == BindingInfoType::Buffer);
            ASSERT(bindingInfo.buffer.hasDynamicOffset);

            uint64_t requiredAlignment;
            switch (bindingInfo.buffer.type) {
                case wgpu::BufferBindingType::Uniform:
                    requiredAlignment = GetDevice()->GetLimits().v1.minUniformBufferOffsetAlignment;
                    break;
                case wgpu::BufferBindingType::Storage:
                case wgpu::BufferBindingType::ReadOnlyStorage:
                case kInternalStorageBufferBinding:
                    requiredAlignment = GetDevice()->GetLimits().v1.minStorageBufferOffsetAlignment;
                    break;
                case wgpu::BufferBindingType::Undefined:
                    UNREACHABLE();
            }

            DAWN_INVALID_IF(!IsAligned(dynamicOffsets[i], requiredAlignment),
                            "Dynamic Offset[%u] (%u) is not %u byte aligned.",
                            static_cast<uint32_t>(i), dynamicOffsets[i], requiredAlignment);

            BufferBinding bufferBinding = group->GetBindingAsBufferBinding(i);

            // During BindGroup creation, validation ensures binding offset + binding size
            // <= buffer size.
            ASSERT(bufferBinding.buffer->GetSize() >= bufferBinding.size);
            ASSERT(bufferBinding.buffer->GetSize() - bufferBinding.size >= bufferBinding.offset);

            if ((dynamicOffsets[i] >
                 bufferBinding.buffer->GetSize() - bufferBinding.offset - bufferBinding.size)) {
                DAWN_INVALID_IF(
                    (bufferBinding.buffer->GetSize() - bufferBinding.offset) == bufferBinding.size,
                    "Dynamic Offset[%u] (%u) is out of bounds of %s with a size of %u and a bound "
                    "range of (offset: %u, size: %u). The binding goes to the end of the buffer "
                    "even with a dynamic offset of 0. Did you forget to specify "
                    "the binding's size?",
                    static_cast<uint32_t>(i), dynamicOffsets[i], bufferBinding.buffer,
                    bufferBinding.buffer->GetSize(), bufferBinding.offset, bufferBinding.size);

                return DAWN_FORMAT_VALIDATION_ERROR(
                    "Dynamic Offset[%u] (%u) is out of bounds of "
                    "%s with a size of %u and a bound range of (offset: %u, size: %u).",
                    static_cast<uint32_t>(i), dynamicOffsets[i], bufferBinding.buffer,
                    bufferBinding.buffer->GetSize(), bufferBinding.offset, bufferBinding.size);
            }
        }

        return {};
    }

    void ProgrammableEncoder::RecordSetBindGroup(CommandAllocator* allocator,
                                                 BindGroupIndex index,
                                                 BindGroupBase* group,
                                                 uint32_t dynamicOffsetCount,
                                                 const uint32_t* dynamicOffsets) const {
        SetBindGroupCmd* cmd = allocator->Allocate<SetBindGroupCmd>(Command::SetBindGroup);
        cmd->index = index;
        cmd->group = group;
        cmd->dynamicOffsetCount = dynamicOffsetCount;
        if (dynamicOffsetCount > 0) {
            uint32_t* offsets = allocator->AllocateData<uint32_t>(cmd->dynamicOffsetCount);
            memcpy(offsets, dynamicOffsets, dynamicOffsetCount * sizeof(uint32_t));
        }
    }

}  // namespace dawn::native