patterns/ico: Add embedded BMP and PNG parsing to ICO pattern (#426)

Co-authored-by: Nik <werwolv98@gmail.com>

patterns/ico.hexpat

@@ -4,6 +4,10 @@
 #pragma endian little
 
 import std.sys;
+import std.mem;
+import std.string;
+import * from bmp as BMP;
+import * from png as PNG;
 
 #pragma MIME image/vnd.microsoft.icon
 #pragma MIME image/x-icon
@@ -23,8 +27,30 @@ struct ICONDIR {
     u16 num_images;
 };
 
+struct BMPData {
+    u8 data[sizeof(parent.data)] [[hidden, no_unique_address]];
+    std::mem::Section section = std::mem::create_section("BMP Image " + std::string::to_string(addressof(this)));
+    std::mem::set_section_size(section, sizeof(data) + 14);
+    u8 headerData[14] @ 0x00 in section [[hidden]];
+    headerData[0x00] = 0x42;
+    headerData[0x01] = 0x4D;
+    u32 size @ 0x02 in section [[hidden]];
+    size = std::mem::get_section_size(section);
+    std::mem::copy_value_to_section(data, section, 0x0E);
+    BMP image @ 0x00 in section;
+    u32 offset @ 0x0D in section [[hidden]];
+    offset = addressof(image.lineData);
+};
+
 struct ImageData {
-	u8 data[parent.image_data_size] [[inline]];
+    std::mem::Bytes<parent.image_data_size> data [[no_unique_address]];
+    be u64 png_magic [[hidden, no_unique_address]];
+    if (png_magic == 0x89504e470d0a1a0a) {
+        PNG png_image @ $ [[inline, highlight_hidden]];
+    } else {
+        BMPData data [[hidden]];
+        BMP bmp_image @ addressof(this) - 14 [[inline, highlight_hidden]];
+    }
 };
 
 struct ICONDIRENTRY {
@@ -41,7 +67,8 @@ struct ICONDIRENTRY {
     }
 
     u32 image_data_size;
-	ImageData *image_data : u32;
+    u32 image_data_offset;
+    ImageData image_data @ image_data_offset;
 };
 
 ICONDIR header @ 0x00;