From ed3d0d76ecb73bd0bb08f53c100905289062ae20 Mon Sep 17 00:00:00 2001
From: Kenneth Myhra <kennethmyhra@gmail.com>
Date: Sat, 19 Jul 2025 08:07:15 +0200
Subject: [PATCH] LibWeb: Implement transfer {,receiving} steps for ImageBitmap

---
 Libraries/LibWeb/HTML/ImageBitmap.cpp         | 25 ++++++++++++-------
 Libraries/LibWeb/HTML/StructuredSerialize.cpp |  5 ++++
 .../LibWeb/HTML/StructuredSerializeTypes.h    |  1 +
 3 files changed, 22 insertions(+), 9 deletions(-)

diff --git a/Libraries/LibWeb/HTML/ImageBitmap.cpp b/Libraries/LibWeb/HTML/ImageBitmap.cpp
index ed02e9ee54e..c60955ec523 100644
--- a/Libraries/LibWeb/HTML/ImageBitmap.cpp
+++ b/Libraries/LibWeb/HTML/ImageBitmap.cpp
@@ -82,25 +82,32 @@ WebIDL::ExceptionOr<void> ImageBitmap::deserialization_steps(HTML::TransferDataD
     return {};
 }
 
-WebIDL::ExceptionOr<void> ImageBitmap::transfer_steps(HTML::TransferDataEncoder&)
+// https://html.spec.whatwg.org/multipage/imagebitmap-and-animations.html#the-imagebitmap-interface:transfer-steps
+WebIDL::ExceptionOr<void> ImageBitmap::transfer_steps(HTML::TransferDataEncoder& data_holder)
 {
-    // FIXME: Implement this
-    dbgln("(STUBBED) ImageBitmap::transfer_steps(HTML::TransferDataEncoder&)");
+    // FIXME: 1. If value's origin-clean flag is not set, then throw a "DataCloneError" DOMException.
+
+    // 2. Set dataHolder.[[BitmapData]] to value's bitmap data.
+    serialize_bitmap(data_holder, *m_bitmap);
+
+    // 3. Unset value's bitmap data.
+    m_bitmap = nullptr;
+
     return {};
 }
 
-WebIDL::ExceptionOr<void> ImageBitmap::transfer_receiving_steps(HTML::TransferDataDecoder&)
+// https://html.spec.whatwg.org/multipage/imagebitmap-and-animations.html#the-imagebitmap-interface:transfer-receiving-steps
+WebIDL::ExceptionOr<void> ImageBitmap::transfer_receiving_steps(HTML::TransferDataDecoder& data_holder)
 {
-    // FIXME: Implement this
-    dbgln("(STUBBED) ImageBitmap::transfer_receiving_steps(HTML::TransferDataDecoder&)");
+    // 1. Set value's bitmap data to dataHolder.[[BitmapData]].
+    m_bitmap = TRY(deserialize_bitmap(this->realm(), data_holder));
+
     return {};
 }
 
 HTML::TransferType ImageBitmap::primary_interface() const
 {
-    // FIXME: Implement this
-    dbgln("(STUBBED) ImageBitmap::primary_interface()");
-    return TransferType::Unknown;
+    return TransferType::ImageBitmap;
 }
 
 // https://html.spec.whatwg.org/multipage/imagebitmap-and-animations.html#dom-imagebitmap-width
diff --git a/Libraries/LibWeb/HTML/StructuredSerialize.cpp b/Libraries/LibWeb/HTML/StructuredSerialize.cpp
index 647ee274be2..c8ecae97c15 100644
--- a/Libraries/LibWeb/HTML/StructuredSerialize.cpp
+++ b/Libraries/LibWeb/HTML/StructuredSerialize.cpp
@@ -1147,6 +1147,11 @@ static WebIDL::ExceptionOr<GC::Ref<Bindings::PlatformObject>> create_transferred
         TRY(transform_stream->transfer_receiving_steps(decoder));
         return transform_stream;
     }
+    case TransferType::ImageBitmap: {
+        auto image_bitmap = target_realm.create<ImageBitmap>(target_realm);
+        TRY(image_bitmap->transfer_receiving_steps(decoder));
+        return image_bitmap;
+    }
     case TransferType::ArrayBuffer:
     case TransferType::ResizableArrayBuffer:
     case TransferType::Unknown:
diff --git a/Libraries/LibWeb/HTML/StructuredSerializeTypes.h b/Libraries/LibWeb/HTML/StructuredSerializeTypes.h
index 6f1a52cad41..a926ceac4d1 100644
--- a/Libraries/LibWeb/HTML/StructuredSerializeTypes.h
+++ b/Libraries/LibWeb/HTML/StructuredSerializeTypes.h
@@ -44,6 +44,7 @@ enum class TransferType : u8 {
     ReadableStream = 4,
     WritableStream = 5,
     TransformStream = 6,
+    ImageBitmap = 7,
 };
 
 }