#include "Rendering/Viewport/ViewportRenderTargetInternal.h"

#include <algorithm>
#include <cmath>

namespace XCEngine::UI::Editor::App {

bool ViewportRequiresObjectIdResources(ViewportKind kind) {
    return kind == ViewportKind::Scene;
}

std::uint32_t ClampViewportPixelCoordinate(float value, std::uint32_t extent) {
    if (extent == 0u) {
        return 0u;
    }

    const float maxCoordinate = static_cast<float>(extent - 1u);
    const float clamped = (std::max)(0.0f, (std::min)(value, maxCoordinate));
    return static_cast<std::uint32_t>(std::floor(clamped));
}

bool CanReuseViewportResources(const ViewportResourceReuseQuery& query) {
    if (query.requestedWidth == 0u || query.requestedHeight == 0u) {
        return false;
    }

    if (query.width != query.requestedWidth || query.height != query.requestedHeight) {
        return false;
    }

    if (!query.resources.hasColorTexture ||
        !query.resources.hasColorView ||
        !query.resources.hasDepthTexture ||
        !query.resources.hasDepthView ||
        !query.resources.hasTextureDescriptor) {
        return false;
    }

    if (!ViewportRequiresObjectIdResources(query.kind)) {
        return true;
    }

    return query.resources.hasObjectIdTexture &&
        query.resources.hasObjectIdDepthTexture &&
        query.resources.hasObjectIdDepthView &&
        query.resources.hasObjectIdView &&
        query.resources.hasObjectIdShaderView &&
        query.resources.hasDepthShaderView &&
        query.resources.hasSelectionMaskTexture &&
        query.resources.hasSelectionMaskView &&
        query.resources.hasSelectionMaskShaderView;
}

::XCEngine::RHI::TextureDesc BuildViewportTextureDesc(
    std::uint32_t width,
    std::uint32_t height,
    ::XCEngine::RHI::Format format) {
    ::XCEngine::RHI::TextureDesc desc = {};
    desc.width = width;
    desc.height = height;
    desc.depth = 1;
    desc.mipLevels = 1;
    desc.arraySize = 1;
    desc.format = static_cast<std::uint32_t>(format);
    desc.textureType = static_cast<std::uint32_t>(::XCEngine::RHI::TextureType::Texture2D);
    desc.sampleCount = 1;
    desc.sampleQuality = 0;
    desc.flags = 0;
    return desc;
}

::XCEngine::RHI::ResourceViewDesc BuildViewportTextureViewDesc(
    ::XCEngine::RHI::Format format) {
    ::XCEngine::RHI::ResourceViewDesc desc = {};
    desc.format = static_cast<std::uint32_t>(format);
    desc.dimension = ::XCEngine::RHI::ResourceViewDimension::Texture2D;
    return desc;
}

::XCEngine::Rendering::RenderSurface BuildViewportRenderSurface(
    std::uint32_t width,
    std::uint32_t height,
    ::XCEngine::RHI::RHIResourceView* colorView,
    ::XCEngine::RHI::RHIResourceView* depthView,
    ::XCEngine::RHI::ResourceStates colorStateBefore,
    ::XCEngine::RHI::ResourceStates colorStateAfter) {
    ::XCEngine::Rendering::RenderSurface surface(width, height);
    surface.SetColorAttachment(colorView);
    surface.SetDepthAttachment(depthView);
    surface.SetColorStateBefore(colorStateBefore);
    surface.SetColorStateAfter(colorStateAfter);
    return surface;
}

} // namespace XCEngine::UI::Editor::App