1 files changed, 77 insertions, 0 deletions
diff --git a/servo/components/style/gecko/values.rs b/servo/components/style/gecko/values.rs
new file mode 100644
index 0000000000..d04c73c70f
--- /dev/null
+++ b/servo/components/style/gecko/values.rs
@@ -0,0 +1,77 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+#![allow(unsafe_code)]
+
+//! Different kind of helpers to interact with Gecko values.
+
+use crate::color::{AbsoluteColor, ColorSpace};
+use crate::counter_style::{Symbol, Symbols};
+use crate::gecko_bindings::bindings;
+use crate::gecko_bindings::structs::CounterStylePtr;
+use crate::values::generics::CounterStyle;
+use crate::values::Either;
+use crate::Atom;
+
+/// Convert a color value to `nscolor`.
+pub fn convert_absolute_color_to_nscolor(color: &AbsoluteColor) -> u32 {
+    let srgb = color.to_color_space(ColorSpace::Srgb);
+    u32::from_le_bytes([
+        (srgb.components.0 * 255.0).round() as u8,
+        (srgb.components.1 * 255.0).round() as u8,
+        (srgb.components.2 * 255.0).round() as u8,
+        (srgb.alpha * 255.0).round() as u8,
+    ])
+}
+
+/// Convert a given `nscolor` to a Servo AbsoluteColor value.
+pub fn convert_nscolor_to_absolute_color(color: u32) -> AbsoluteColor {
+    let [r, g, b, a] = color.to_le_bytes();
+    AbsoluteColor::srgb_legacy(r, g, b, a as f32 / 255.0)
+}
+
+#[test]
+fn convert_ns_color_to_absolute_color_should_be_in_legacy_syntax() {
+    use crate::color::ColorFlags;
+
+    let result = convert_nscolor_to_absolute_color(0x336699CC);
+    assert!(result.flags.contains(ColorFlags::IS_LEGACY_SRGB));
+
+    assert!(result.is_legacy_syntax());
+}
+
+impl CounterStyle {
+    /// Convert this counter style to a Gecko CounterStylePtr.
+    #[inline]
+    pub fn to_gecko_value(&self, gecko_value: &mut CounterStylePtr) {
+        unsafe { bindings::Gecko_CounterStyle_ToPtr(self, gecko_value) }
+    }
+
+    /// Convert Gecko CounterStylePtr to CounterStyle or String.
+    pub fn from_gecko_value(gecko_value: &CounterStylePtr) -> Either<Self, String> {
+        use crate::values::CustomIdent;
+
+        let name = unsafe { bindings::Gecko_CounterStyle_GetName(gecko_value) };
+        if !name.is_null() {
+            let name = unsafe { Atom::from_raw(name) };
+            debug_assert_ne!(name, atom!("none"));
+            Either::First(CounterStyle::Name(CustomIdent(name)))
+        } else {
+            let anonymous =
+                unsafe { bindings::Gecko_CounterStyle_GetAnonymous(gecko_value).as_ref() }.unwrap();
+            let symbols = &anonymous.mSymbols;
+            if anonymous.mSingleString {
+                debug_assert_eq!(symbols.len(), 1);
+                Either::Second(symbols[0].to_string())
+            } else {
+                let symbol_type = anonymous.mSymbolsType;
+                let symbols = symbols
+                    .iter()
+                    .map(|gecko_symbol| Symbol::String(gecko_symbol.to_string().into()))
+                    .collect();
+                Either::First(CounterStyle::Symbols(symbol_type, Symbols(symbols)))
+            }
+        }
+    }
+}