// Copyright 2017 The Dawn & Tint Authors
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are met:
//
// 1. Redistributions of source code must retain the above copyright notice, this
//    list of conditions and the following disclaimer.
//
// 2. Redistributions in binary form must reproduce the above copyright notice,
//    this list of conditions and the following disclaimer in the documentation
//    and/or other materials provided with the distribution.
//
// 3. Neither the name of the copyright holder nor the names of its
//    contributors may be used to endorse or promote products derived from
//    this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
// DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
// FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
// DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
// SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
// CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
// OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

#include "dawn/tests/DawnTest.h"

#include "dawn/utils/ComboRenderPipelineDescriptor.h"
#include "dawn/utils/WGPUHelpers.h"

namespace dawn {
namespace {

class ViewportOrientationTests : public DawnTest {};

// Test that the pixel in viewport coordinate (-1, -1) matches texel (0, 0)
TEST_P(ViewportOrientationTests, OriginAt0x0) {
    utils::BasicRenderPass renderPass = utils::CreateBasicRenderPass(device, 2, 2);

    wgpu::ShaderModule vsModule = utils::CreateShaderModule(device, R"(
        @vertex fn main() -> @builtin(position) vec4f {
            return vec4f(-0.5, 0.5, 0.0, 1.0);
        })");

    wgpu::ShaderModule fsModule = utils::CreateShaderModule(device, R"(
        @fragment fn main() -> @location(0) vec4f {
            return vec4f(0.0, 1.0, 0.0, 1.0);
        })");

    utils::ComboRenderPipelineDescriptor descriptor;
    descriptor.vertex.module = vsModule;
    descriptor.cFragment.module = fsModule;
    descriptor.primitive.topology = wgpu::PrimitiveTopology::PointList;
    descriptor.cTargets[0].format = renderPass.colorFormat;

    wgpu::RenderPipeline pipeline = device.CreateRenderPipeline(&descriptor);

    wgpu::CommandEncoder encoder = device.CreateCommandEncoder();
    {
        wgpu::RenderPassEncoder pass = encoder.BeginRenderPass(&renderPass.renderPassInfo);
        pass.SetPipeline(pipeline);
        pass.Draw(1);
        pass.End();
    }

    wgpu::CommandBuffer commands = encoder.Finish();
    queue.Submit(1, &commands);

    EXPECT_PIXEL_RGBA8_EQ(utils::RGBA8::kGreen, renderPass.color, 0, 0);
    EXPECT_PIXEL_RGBA8_EQ(utils::RGBA8::kZero, renderPass.color, 0, 1);
    EXPECT_PIXEL_RGBA8_EQ(utils::RGBA8::kZero, renderPass.color, 1, 0);
    EXPECT_PIXEL_RGBA8_EQ(utils::RGBA8::kZero, renderPass.color, 1, 1);
}

DAWN_INSTANTIATE_TEST(ViewportOrientationTests,
                      D3D11Backend(),
                      D3D12Backend(),
                      MetalBackend(),
                      OpenGLBackend(),
                      OpenGLESBackend(),
                      VulkanBackend());

}  // anonymous namespace
}  // namespace dawn