From dc91d047de40a36c72daa7cbe227ccc55fe7f525 Mon Sep 17 00:00:00 2001
From: apio <blobs.trading@gmail.com>
Date: Fri, 4 Aug 2023 21:16:31 +0200
Subject: [PATCH] libui: Add support for TGA image loading

---
 libui/CMakeLists.txt     |  1 +
 libui/include/ui/Image.h | 71 ++++++++++++++++++++++++++++++++++++++++
 libui/src/Image.cpp      | 24 ++++++++++++++
 3 files changed, 96 insertions(+)
 create mode 100644 libui/include/ui/Image.h
 create mode 100644 libui/src/Image.cpp

diff --git a/libui/CMakeLists.txt b/libui/CMakeLists.txt
index c28eb3e2..1a0fa74b 100644
--- a/libui/CMakeLists.txt
+++ b/libui/CMakeLists.txt
@@ -7,6 +7,7 @@ set(SOURCES
     src/Canvas.cpp
     src/Rect.cpp
     src/Font.cpp
+    src/Image.cpp
 )
 
 add_library(ui ${SOURCES})
diff --git a/libui/include/ui/Image.h b/libui/include/ui/Image.h
new file mode 100644
index 00000000..fa1cdb39
--- /dev/null
+++ b/libui/include/ui/Image.h
@@ -0,0 +1,71 @@
+#pragma once
+#include <luna/Buffer.h>
+#include <luna/SharedPtr.h>
+#include <os/Path.h>
+
+namespace ui
+{
+    /**
+     * @brief An image in the TGA file format.
+     */
+    class Image : public Shareable
+    {
+      public:
+        /**
+         * @brief Load a new TGA image from a file.
+         *
+         * @param path The path to open.
+         * @return Result<SharedPtr<Image>> An error, or a new Image object.
+         */
+        static Result<SharedPtr<Image>> load(const os::Path& path);
+
+        /**
+         * @brief Return the array of pixels contained in the image.
+         *
+         * @return u32* The array of pixels.
+         */
+        u32* pixels()
+        {
+            return (u32*)m_image_data.data();
+        }
+
+        /**
+         * @brief Return the width of the image.
+         *
+         * @return u16 The width.
+         */
+        u16 width()
+        {
+            return m_tga_header.w;
+        }
+
+        /**
+         * @brief Return the height of the image.
+         *
+         * @return u16 The height.
+         */
+        u16 height()
+        {
+            return m_tga_header.h;
+        }
+
+      private:
+        struct [[gnu::packed]] TGAHeader
+        {
+            u8 idlen;
+            u8 colormap;
+            u8 encoding;
+            u16 cmaporig, cmaplen;
+            u8 cmapent;
+            u16 x;
+            u16 y;
+            u16 w;
+            u16 h;
+            u8 bpp;
+            u8 pixeltype;
+        };
+
+        TGAHeader m_tga_header;
+        Buffer m_image_data;
+    };
+}
diff --git a/libui/src/Image.cpp b/libui/src/Image.cpp
new file mode 100644
index 00000000..de6051ad
--- /dev/null
+++ b/libui/src/Image.cpp
@@ -0,0 +1,24 @@
+#include <os/File.h>
+#include <ui/Image.h>
+
+namespace ui
+{
+    Result<SharedPtr<Image>> Image::load(const os::Path& path)
+    {
+        auto image = TRY(make_shared<Image>());
+        auto file = TRY(os::File::open(path, os::File::ReadOnly));
+
+        TRY(file->read_typed(image->m_tga_header));
+
+        if (image->m_tga_header.encoding != 2) todo();
+        if (image->m_tga_header.bpp != 32) todo();
+
+        Buffer image_id;
+        TRY(file->read(image_id, image->m_tga_header.idlen));
+
+        TRY(file->read(image->m_image_data,
+                       image->m_tga_header.w * image->m_tga_header.h * (image->m_tga_header.bpp / 8)));
+
+        return image;
+    }
+}