2 files changed, 88 insertions, 3 deletions

diff --git a/src/yuzu/util/util.cpp b/src/yuzu/util/util.cpp
index 5c3e4589e..61cf00176 100644
--- a/src/yuzu/util/util.cpp
+++ b/src/yuzu/util/util.cpp
@@ -5,6 +5,10 @@
 #include <cmath>
 #include <QPainter>
 #include "yuzu/util/util.h"
+#ifdef _WIN32
+#include <windows.h>
+#include "common/fs/file.h"
+#endif
 
 QFont GetMonospaceFont() {
     QFont font(QStringLiteral("monospace"));
@@ -37,3 +41,76 @@ QPixmap CreateCirclePixmapFromColor(const QColor& color) {
     painter.drawEllipse({circle_pixmap.width() / 2.0, circle_pixmap.height() / 2.0}, 7.0, 7.0);
     return circle_pixmap;
 }
+
+bool SaveIconToFile(const std::string_view path, const QImage& image) {
+#if defined(WIN32)
+#pragma pack(push, 2)
+    struct IconDir {
+        WORD id_reserved;
+        WORD id_type;
+        WORD id_count;
+    };
+
+    struct IconDirEntry {
+        BYTE width;
+        BYTE height;
+        BYTE color_count;
+        BYTE reserved;
+        WORD planes;
+        WORD bit_count;
+        DWORD bytes_in_res;
+        DWORD image_offset;
+    };
+#pragma pack(pop)
+
+    QImage source_image = image.convertToFormat(QImage::Format_RGB32);
+    constexpr int bytes_per_pixel = 4;
+    const int image_size = source_image.width() * source_image.height() * bytes_per_pixel;
+
+    BITMAPINFOHEADER info_header{};
+    info_header.biSize = sizeof(BITMAPINFOHEADER), info_header.biWidth = source_image.width(),
+    info_header.biHeight = source_image.height() * 2, info_header.biPlanes = 1,
+    info_header.biBitCount = bytes_per_pixel * 8, info_header.biCompression = BI_RGB;
+
+    const IconDir icon_dir{.id_reserved = 0, .id_type = 1, .id_count = 1};
+    const IconDirEntry icon_entry{.width = static_cast<BYTE>(source_image.width()),
+                                  .height = static_cast<BYTE>(source_image.height() * 2),
+                                  .color_count = 0,
+                                  .reserved = 0,
+                                  .planes = 1,
+                                  .bit_count = bytes_per_pixel * 8,
+                                  .bytes_in_res =
+                                      static_cast<DWORD>(sizeof(BITMAPINFOHEADER) + image_size),
+                                  .image_offset = sizeof(IconDir) + sizeof(IconDirEntry)};
+
+    Common::FS::IOFile icon_file(path, Common::FS::FileAccessMode::Write,
+                                 Common::FS::FileType::BinaryFile);
+    if (!icon_file.IsOpen()) {
+        return false;
+    }
+
+    if (!icon_file.Write(icon_dir)) {
+        return false;
+    }
+    if (!icon_file.Write(icon_entry)) {
+        return false;
+    }
+    if (!icon_file.Write(info_header)) {
+        return false;
+    }
+
+    for (int y = 0; y < image.height(); y++) {
+        const auto* line = source_image.scanLine(source_image.height() - 1 - y);
+        std::vector<u8> line_data(source_image.width() * bytes_per_pixel);
+        std::memcpy(line_data.data(), line, line_data.size());
+        if (!icon_file.Write(line_data)) {
+            return false;
+        }
+    }
+    icon_file.Close();
+
+    return true;
+#else
+    return false;
+#endif
+}
diff --git a/src/yuzu/util/util.h b/src/yuzu/util/util.h
index 39dd2d895..09c14ce3f 100644
--- a/src/yuzu/util/util.h
+++ b/src/yuzu/util/util.h
@@ -7,14 +7,22 @@
 #include <QString>
 
 /// Returns a QFont object appropriate to use as a monospace font for debugging widgets, etc.
-QFont GetMonospaceFont();
+[[nodiscard]] QFont GetMonospaceFont();
 
 /// Convert a size in bytes into a readable format (KiB, MiB, etc.)
-QString ReadableByteSize(qulonglong size);
+[[nodiscard]] QString ReadableByteSize(qulonglong size);
 
 /**
  * Creates a circle pixmap from a specified color
  * @param color The color the pixmap shall have
  * @return QPixmap circle pixmap
  */
-QPixmap CreateCirclePixmapFromColor(const QColor& color);
+[[nodiscard]] QPixmap CreateCirclePixmapFromColor(const QColor& color);
+
+/**
+ * Saves a windows icon to a file
+ * @param path The icons path
+ * @param image The image to save
+ * @return bool If the operation succeeded
+ */
+[[nodiscard]] bool SaveIconToFile(const std::string_view path, const QImage& image);