PowerToys/src/modules/fancyzones/lib/ZoneWindowDrawing.cpp

#include "pch.h"
#include "ZoneWindowDrawing.h"
#include "CallTracer.h"

#include <algorithm>
#include <map>
#include <string>
#include <vector>

#include <common/logger/logger.h>

namespace NonLocalizable
{
    const wchar_t SegoeUiFont[] = L"Segoe ui";
}

float ZoneWindowDrawing::GetAnimationAlpha()
{
    // Lock is being held
    if (!m_animation)
    {
        return 0.f;
    }

    auto tNow = std::chrono::steady_clock().now();
    auto alpha = (tNow - m_animation->tStart).count() / (1e6f * m_animation->duration);

    if (m_animation->fadeIn)
    {
        // Return a positive value to avoid hiding
        return std::clamp(alpha, 0.001f, 1.f);
    }
    else
    {
        // Quadratic function looks better
        return std::clamp(1.f - alpha * alpha, 0.f, 1.f);
    }
}

ID2D1Factory* ZoneWindowDrawing::GetD2DFactory()
{
    static auto pD2DFactory = [] {
        ID2D1Factory* res = nullptr;
        D2D1CreateFactory(D2D1_FACTORY_TYPE_MULTI_THREADED, &res);
        return res;
    }();
    return pD2DFactory;
}

IDWriteFactory* ZoneWindowDrawing::GetWriteFactory()
{
    static auto pDWriteFactory = [] {
        IUnknown* res = nullptr;
        DWriteCreateFactory(DWRITE_FACTORY_TYPE_SHARED, __uuidof(IDWriteFactory), &res);
        return reinterpret_cast<IDWriteFactory*>(res);
    }();
    return pDWriteFactory;
}

D2D1_COLOR_F ZoneWindowDrawing::ConvertColor(COLORREF color)
{
    return D2D1::ColorF(GetRValue(color) / 255.f,
                        GetGValue(color) / 255.f,
                        GetBValue(color) / 255.f,
                        1.f);
}

D2D1_RECT_F ZoneWindowDrawing::ConvertRect(RECT rect)
{
    return D2D1::RectF((float)rect.left + 0.5f, (float)rect.top + 0.5f, (float)rect.right - 0.5f, (float)rect.bottom - 0.5f);
}

ZoneWindowDrawing::ZoneWindowDrawing(HWND window)
{
    HRESULT hr;
    m_window = window;
    m_renderTarget = nullptr;
    m_shouldRender = false;

    // Obtain the size of the drawing area.
    if (!GetClientRect(window, &m_clientRect))
    {
        Logger::error("couldn't initialize ZoneWindowDrawing: GetClientRect failed");
        return;
    }

    // Create a Direct2D render target
    // We should always use the DPI value of 96 since we're running in DPI aware mode
    auto renderTargetProperties = D2D1::RenderTargetProperties(
        D2D1_RENDER_TARGET_TYPE_DEFAULT,
        D2D1::PixelFormat(DXGI_FORMAT_UNKNOWN, D2D1_ALPHA_MODE_PREMULTIPLIED),
        96.f,
        96.f);
    
    auto renderTargetSize = D2D1::SizeU(m_clientRect.right - m_clientRect.left, m_clientRect.bottom - m_clientRect.top);
    auto hwndRenderTargetProperties = D2D1::HwndRenderTargetProperties(window, renderTargetSize);

    hr = GetD2DFactory()->CreateHwndRenderTarget(renderTargetProperties, hwndRenderTargetProperties, &m_renderTarget);

    if (!SUCCEEDED(hr))
    {
        Logger::error("couldn't initialize ZoneWindowDrawing: CreateHwndRenderTarget failed with {}", hr);
        return;
    }

    m_renderThread = std::thread([this]() { RenderLoop(); });
}

void ZoneWindowDrawing::Render()
{
    std::unique_lock lock(m_mutex);

    if (!m_renderTarget)
    {
        return;
    }

    float animationAlpha = GetAnimationAlpha();

    if (animationAlpha <= 0.f)
    {
        return;
    }

    m_renderTarget->BeginDraw();

    // Draw backdrop
    m_renderTarget->Clear(D2D1::ColorF(0.f, 0.f, 0.f, 0.f));

    ID2D1SolidColorBrush* textBrush = nullptr;
    IDWriteTextFormat* textFormat = nullptr;

    m_renderTarget->CreateSolidColorBrush(D2D1::ColorF(D2D1::ColorF::Black, animationAlpha), &textBrush);
    auto writeFactory = GetWriteFactory();

    if (writeFactory)
    {
        writeFactory->CreateTextFormat(NonLocalizable::SegoeUiFont, nullptr, DWRITE_FONT_WEIGHT_NORMAL, DWRITE_FONT_STYLE_NORMAL, DWRITE_FONT_STRETCH_NORMAL, 80.f, L"en-US", &textFormat);
    }

    for (auto drawableRect : m_sceneRects)
    {
        ID2D1SolidColorBrush* borderBrush = nullptr;
        ID2D1SolidColorBrush* fillBrush = nullptr;

        // Need to copy the rect from m_sceneRects
        drawableRect.borderColor.a *= animationAlpha;
        drawableRect.fillColor.a *= animationAlpha;

        m_renderTarget->CreateSolidColorBrush(drawableRect.borderColor, &borderBrush);
        m_renderTarget->CreateSolidColorBrush(drawableRect.fillColor, &fillBrush);

        if (fillBrush)
        {
            m_renderTarget->FillRectangle(drawableRect.rect, fillBrush);
            fillBrush->Release();
        }

        if (borderBrush)
        {
            m_renderTarget->DrawRectangle(drawableRect.rect, borderBrush);
            borderBrush->Release();
        }

        std::wstring idStr = std::to_wstring(drawableRect.id + 1);

        if (textFormat && textBrush)
        {
            textFormat->SetTextAlignment(DWRITE_TEXT_ALIGNMENT_CENTER);
            textFormat->SetParagraphAlignment(DWRITE_PARAGRAPH_ALIGNMENT_CENTER);
            m_renderTarget->DrawTextW(idStr.c_str(), (UINT32)idStr.size(), textFormat, drawableRect.rect, textBrush);
        }
    }

    if (textFormat)
    {
        textFormat->Release();
    }

    if (textBrush)
    {
        textBrush->Release();
    }

    // The lock must be released here, as EndDraw() will wait for vertical sync
    lock.unlock();

    m_renderTarget->EndDraw();
}

void ZoneWindowDrawing::RenderLoop()
{
    while (!m_abortThread)
    {
        float animationAlpha;
        {
            // The lock must be held by the caller when calling GetAnimationAlpha
            std::unique_lock lock(m_mutex);
            animationAlpha = GetAnimationAlpha();
        }

        // Check whether the animation expired and we need to hide the window
        if (animationAlpha <= 0.f)
        {
            Hide();
        }

        {
            // Wait here while rendering is disabled
            std::unique_lock lock(m_mutex);
            m_cv.wait(lock, [this]() { return (bool)m_shouldRender; });
        }
        
        Render();
    }
}

void ZoneWindowDrawing::Hide()
{
    _TRACER_;
    std::unique_lock lock(m_mutex);

    m_animation.reset();

    if (m_shouldRender)
    {
        m_shouldRender = false;
        ShowWindow(m_window, SW_HIDE);
    }
}

void ZoneWindowDrawing::Show(unsigned animationMillis)
{
    _TRACER_;
    std::unique_lock lock(m_mutex);
    
    if (!m_shouldRender)
    {
        ShowWindow(m_window, SW_SHOWNA);
    }

    animationMillis = max(animationMillis, 1);

    if (!m_animation || !m_animation->fadeIn)
    {
        m_animation.emplace(AnimationInfo{ std::chrono::steady_clock().now(), animationMillis, true });
    }

    m_shouldRender = true;
    m_cv.notify_all();
}

void ZoneWindowDrawing::Flash(unsigned animationMillis)
{
    _TRACER_;
    std::unique_lock lock(m_mutex);

    if (!m_shouldRender)
    {
        ShowWindow(m_window, SW_SHOWNA);
    }

    animationMillis = max(animationMillis, 1);

    m_animation.emplace(AnimationInfo{ std::chrono::steady_clock().now(), animationMillis, false });

    m_shouldRender = true;
    m_cv.notify_all();
}

void ZoneWindowDrawing::DrawActiveZoneSet(const IZoneSet::ZonesMap& zones,
                       const std::vector<size_t>& highlightZones,
                       winrt::com_ptr<IZoneWindowHost> host)
{
    _TRACER_;
    std::unique_lock lock(m_mutex);

    m_sceneRects = {};

    auto borderColor = ConvertColor(host->GetZoneBorderColor());
    auto inactiveColor = ConvertColor(host->GetZoneColor());
    auto highlightColor = ConvertColor(host->GetZoneHighlightColor());

    inactiveColor.a = host->GetZoneHighlightOpacity() / 100.f;
    highlightColor.a = host->GetZoneHighlightOpacity() / 100.f;

    std::vector<bool> isHighlighted(zones.size() + 1, false);
    for (size_t x : highlightZones)
    {
        isHighlighted[x] = true;
    }

    // First draw the inactive zones
    for (const auto& [zoneId, zone] : zones)
    {
        if (!zone)
        {
            continue;
        }

        if (!isHighlighted[zoneId])
        {
            DrawableRect drawableRect{
                .rect = ConvertRect(zone->GetZoneRect()),
                .borderColor = borderColor,
                .fillColor = inactiveColor,
                .id = zone->Id()
            };

            m_sceneRects.push_back(drawableRect);
        }
    }

    // Draw the active zones on top of the inactive zones
    for (const auto& [zoneId, zone] : zones)
    {
        if (!zone)
        {
            continue;
        }

        if (isHighlighted[zoneId])
        {
            DrawableRect drawableRect{
                .rect = ConvertRect(zone->GetZoneRect()),
                .borderColor = borderColor,
                .fillColor = highlightColor,
                .id = zone->Id()
            };

            m_sceneRects.push_back(drawableRect);
        }
    }
}

ZoneWindowDrawing::~ZoneWindowDrawing()
{
    {
        std::unique_lock lock(m_mutex);
        m_abortThread = true;
        m_shouldRender = true;
    }
    m_cv.notify_all();
    m_renderThread.join();

    if (m_renderTarget)
    {
        m_renderTarget->Release();
    }
}