LibWeb: Update displayed favicon when a favicon is loaded

When a favicon has been loaded, trigger a favicon update on
document level. Of all the link tags in the header, the last
favicon that is load should be shown.

When the favicon could not be loaded, load the next icon in reverse tree
order.

2 files changed, 68 insertions, 0 deletions

diff --git a/Userland/Libraries/LibWeb/HTML/HTMLLinkElement.cpp b/Userland/Libraries/LibWeb/HTML/HTMLLinkElement.cpp
index 722e2b2508..f6b601f9c3 100644
--- a/Userland/Libraries/LibWeb/HTML/HTMLLinkElement.cpp
+++ b/Userland/Libraries/LibWeb/HTML/HTMLLinkElement.cpp
@@ -12,7 +12,9 @@
 #include <LibWeb/CSS/Parser/Parser.h>
 #include <LibWeb/DOM/Document.h>
 #include <LibWeb/HTML/HTMLLinkElement.h>
+#include <LibWeb/ImageDecoding.h>
 #include <LibWeb/Loader/ResourceLoader.h>
+#include <LibWeb/Page/Page.h>
 
 namespace Web::HTML {
 
@@ -50,9 +52,18 @@ void HTMLLinkElement::inserted()
         ResourceLoader::the().prefetch_dns(document().parse_url(attribute(HTML::AttributeNames::href)));
     } else if (m_relationship & Relationship::Preconnect) {
         ResourceLoader::the().preconnect(document().parse_url(attribute(HTML::AttributeNames::href)));
+    } else if (m_relationship & Relationship::Icon) {
+        auto favicon_url = document().parse_url(href());
+        auto favicon_request = LoadRequest::create_for_url_on_page(favicon_url, document().page());
+        set_resource(ResourceLoader::the().load_resource(Resource::Type::Generic, favicon_request));
     }
 }
 
+bool HTMLLinkElement::has_loaded_icon() const
+{
+    return m_relationship & Relationship::Icon && resource() && resource()->is_loaded() && resource()->has_encoded_data();
+}
+
 void HTMLLinkElement::parse_attribute(FlyString const& name, String const& value)
 {
     // 4.6.7 Link types - https://html.spec.whatwg.org/multipage/links.html#linkTypes
@@ -91,7 +102,17 @@ void HTMLLinkElement::resource_did_fail()
 void HTMLLinkElement::resource_did_load()
 {
     VERIFY(resource());
+    VERIFY(m_relationship & (Relationship::Stylesheet | Relationship::Icon));
 
+    if (m_relationship & Relationship::Stylesheet)
+        resource_did_load_stylesheet();
+    if (m_relationship & Relationship::Icon)
+        resource_did_load_favicon();
+}
+
+void HTMLLinkElement::resource_did_load_stylesheet()
+{
+    VERIFY(m_relationship & Relationship::Stylesheet);
     m_document_load_event_delayer.clear();
 
     if (!resource()->has_encoded_data()) {
@@ -115,4 +136,45 @@ void HTMLLinkElement::resource_did_load()
     document().style_sheets().add_sheet(sheet.release_nonnull());
 }
 
+void HTMLLinkElement::resource_did_load_favicon()
+{
+    VERIFY(m_relationship & (Relationship::Icon));
+    if (!resource()->has_encoded_data()) {
+        dbgln_if(SPAM_DEBUG, "Favicon downloaded, no encoded data");
+        return;
+    }
+
+    dbgln_if(SPAM_DEBUG, "Favicon downloaded, {} bytes from {}", resource()->encoded_data().size(), resource()->url());
+
+    document().check_favicon_after_loading_link_resource();
+}
+
+bool HTMLLinkElement::load_favicon_and_use_if_window_is_active()
+{
+    if (!has_loaded_icon())
+        return false;
+
+    RefPtr<Gfx::Bitmap> favicon_bitmap;
+    auto decoded_image = Web::image_decoder_client().decode_image(resource()->encoded_data());
+    if (!decoded_image.has_value() || decoded_image->frames.is_empty()) {
+        dbgln("Could not decode favicon {}", resource()->url());
+        return false;
+    }
+
+    favicon_bitmap = decoded_image->frames[0].bitmap;
+    dbgln_if(IMAGE_DECODER_DEBUG, "Decoded favicon, {}", favicon_bitmap->size());
+
+    auto* page = document().page();
+    if (!page)
+        return favicon_bitmap;
+
+    if (document().browsing_context() == &page->top_level_browsing_context())
+        if (favicon_bitmap) {
+            page->client().page_did_change_favicon(*favicon_bitmap);
+            return true;
+        }
+
+    return false;
+}
+
 }
diff --git a/Userland/Libraries/LibWeb/HTML/HTMLLinkElement.h b/Userland/Libraries/LibWeb/HTML/HTMLLinkElement.h
index eab494ad09..844bba4149 100644
--- a/Userland/Libraries/LibWeb/HTML/HTMLLinkElement.h
+++ b/Userland/Libraries/LibWeb/HTML/HTMLLinkElement.h
@@ -28,6 +28,9 @@ public:
     String type() const { return attribute(HTML::AttributeNames::type); }
     String href() const { return attribute(HTML::AttributeNames::href); }
 
+    bool has_loaded_icon() const;
+    bool load_favicon_and_use_if_window_is_active();
+
 private:
     void parse_attribute(FlyString const&, String const&) override;
 
@@ -35,6 +38,9 @@ private:
     virtual void resource_did_fail() override;
     virtual void resource_did_load() override;
 
+    void resource_did_load_stylesheet();
+    void resource_did_load_favicon();
+
     struct Relationship {
         enum {
             Alternate = 1 << 0,