From 0121e7028f91af583f15482bc4fde07051f29b30 Mon Sep 17 00:00:00 2001
From: Sam Atkins <sam@ladybird.org>
Date: Fri, 4 Apr 2025 15:30:36 +0100
Subject: [PATCH] LibWeb/CSS: Make "CSSStyleValue -> list of font sources" code
 accessible

We'll want this in FontFace.
---
 Libraries/LibWeb/CSS/ParsedFontFace.cpp | 59 ++++++++++++++-----------
 Libraries/LibWeb/CSS/ParsedFontFace.h   |  1 +
 2 files changed, 34 insertions(+), 26 deletions(-)

diff --git a/Libraries/LibWeb/CSS/ParsedFontFace.cpp b/Libraries/LibWeb/CSS/ParsedFontFace.cpp
index e4f3ae0ce84..94f11f54d40 100644
--- a/Libraries/LibWeb/CSS/ParsedFontFace.cpp
+++ b/Libraries/LibWeb/CSS/ParsedFontFace.cpp
@@ -21,16 +21,40 @@
 
 namespace Web::CSS {
 
-ParsedFontFace ParsedFontFace::from_descriptors(CSSFontFaceDescriptors const& descriptors)
+static FlyString extract_font_name(CSSStyleValue const& value)
 {
-    auto extract_font_name = [](CSSStyleValue const& value) {
-        if (value.is_string())
-            return value.as_string().string_value();
-        if (value.is_custom_ident())
-            return value.as_custom_ident().custom_ident();
-        return FlyString {};
+    if (value.is_string())
+        return value.as_string().string_value();
+    if (value.is_custom_ident())
+        return value.as_custom_ident().custom_ident();
+    return FlyString {};
+}
+
+Vector<ParsedFontFace::Source> ParsedFontFace::sources_from_style_value(CSSStyleValue const& style_value)
+{
+    Vector<Source> sources;
+    auto add_source = [&sources](FontSourceStyleValue const& font_source) {
+        font_source.source().visit(
+            [&](FontSourceStyleValue::Local const& local) {
+                sources.empend(extract_font_name(local.name), OptionalNone {});
+            },
+            [&](URL::URL const& url) {
+                // FIXME: tech()
+                sources.empend(url, font_source.format());
+            });
     };
 
+    if (style_value.is_font_source()) {
+        add_source(style_value.as_font_source());
+    } else if (style_value.is_value_list()) {
+        for (auto const& source : style_value.as_value_list().values())
+            add_source(source->as_font_source());
+    }
+    return sources;
+}
+
+ParsedFontFace ParsedFontFace::from_descriptors(CSSFontFaceDescriptors const& descriptors)
+{
     auto extract_percentage_or_normal = [](CSSStyleValue const& value) -> Optional<Percentage> {
         if (value.is_percentage())
             return value.as_percentage().percentage();
@@ -61,25 +85,8 @@ ParsedFontFace ParsedFontFace::from_descriptors(CSSFontFaceDescriptors const& de
         width = value->to_font_width();
 
     Vector<Source> sources;
-    if (auto value = descriptors.descriptor_or_initial_value(DescriptorID::Src)) {
-        auto add_source = [&sources, extract_font_name](FontSourceStyleValue const& font_source) {
-            font_source.source().visit(
-                [&](FontSourceStyleValue::Local const& local) {
-                    sources.empend(extract_font_name(local.name), OptionalNone {});
-                },
-                [&](URL::URL const& url) {
-                    // FIXME: tech()
-                    sources.empend(url, font_source.format());
-                });
-        };
-
-        if (value->is_font_source()) {
-            add_source(value->as_font_source());
-        } else if (value->is_value_list()) {
-            for (auto const& source : value->as_value_list().values())
-                add_source(source->as_font_source());
-        }
-    }
+    if (auto value = descriptors.descriptor_or_initial_value(DescriptorID::Src))
+        sources = sources_from_style_value(*value);
 
     Vector<Gfx::UnicodeRange> unicode_ranges;
     if (auto value = descriptors.descriptor_or_initial_value(DescriptorID::UnicodeRange)) {
diff --git a/Libraries/LibWeb/CSS/ParsedFontFace.h b/Libraries/LibWeb/CSS/ParsedFontFace.h
index 09b03f173a6..b52bcde095e 100644
--- a/Libraries/LibWeb/CSS/ParsedFontFace.h
+++ b/Libraries/LibWeb/CSS/ParsedFontFace.h
@@ -24,6 +24,7 @@ public:
         Optional<FlyString> format;
     };
 
+    static Vector<Source> sources_from_style_value(CSSStyleValue const&);
     static ParsedFontFace from_descriptors(CSSFontFaceDescriptors const&);
 
     ParsedFontFace(FlyString font_family, Optional<int> weight, Optional<int> slope, Optional<int> width, Vector<Source> sources, Vector<Gfx::UnicodeRange> unicode_ranges, Optional<Percentage> ascent_override, Optional<Percentage> descent_override, Optional<Percentage> line_gap_override, FontDisplay font_display, Optional<FlyString> font_named_instance, Optional<FlyString> font_language_override, Optional<OrderedHashMap<FlyString, i64>> font_feature_settings, Optional<OrderedHashMap<FlyString, double>> font_variation_settings);