// Copyright 2021 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/ScratchBuffer.h"

#include "dawn_native/Device.h"

namespace dawn_native {

    ScratchBuffer::ScratchBuffer(DeviceBase* device, wgpu::BufferUsage usage)
        : mDevice(device), mUsage(usage) {
    }

    ScratchBuffer::~ScratchBuffer() = default;

    void ScratchBuffer::Reset() {
        mBuffer = nullptr;
    }

    MaybeError ScratchBuffer::EnsureCapacity(uint64_t capacity) {
        if (!mBuffer.Get() || mBuffer->GetSize() < capacity) {
            BufferDescriptor descriptor;
            descriptor.size = capacity;
            descriptor.usage = mUsage;
            DAWN_TRY_ASSIGN(mBuffer, mDevice->CreateBuffer(&descriptor));
            mBuffer->SetIsDataInitialized();
        }
        return {};
    }

    BufferBase* ScratchBuffer::GetBuffer() const {
        ASSERT(mBuffer.Get() != nullptr);
        return mBuffer.Get();
    }

}  // namespace dawn_native