Add CSSKeyframesRule.{findRule, deleteRule, appendRule}

components/script/dom/csskeyframesrule.rs

@@ -2,20 +2,25 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
+use cssparser::Parser;
 use dom::bindings::codegen::Bindings::CSSKeyframesRuleBinding;
 use dom::bindings::codegen::Bindings::CSSKeyframesRuleBinding::CSSKeyframesRuleMethods;
 use dom::bindings::codegen::Bindings::CSSRuleBinding::CSSRuleMethods;
+use dom::bindings::codegen::Bindings::WindowBinding::WindowBinding::WindowMethods;
 use dom::bindings::inheritance::Castable;
 use dom::bindings::js::{JS, MutNullableHeap, Root};
 use dom::bindings::reflector::{Reflectable, reflect_dom_object};
 use dom::bindings::str::DOMString;
+use dom::csskeyframerule::CSSKeyframeRule;
 use dom::cssrule::{CSSRule, SpecificCSSRule};
 use dom::cssrulelist::{CSSRuleList, RulesSource};
 use dom::cssstylesheet::CSSStyleSheet;
 use dom::window::Window;
 use parking_lot::RwLock;
 use std::sync::Arc;
-use style::stylesheets::KeyframesRule;
+use style::keyframes::{Keyframe, KeyframeSelector};
+use style::parser::ParserContextExtraData;
+use style::stylesheets::{KeyframesRule, Origin};
 use style_traits::ToCss;
 
 #[dom_struct]
@@ -52,6 +57,21 @@ impl CSSKeyframesRule {
                              RulesSource::Keyframes(self.keyframesrule.clone()))
         })
     }
+
+    /// Given a keyframe selector, finds the index of the first corresponding rule if any
+    fn find_rule(&self, selector: &str) -> Option<usize> {
+        let mut input = Parser::new(selector);
+        if let Ok(sel) = KeyframeSelector::parse(&mut input) {
+            // This finds the *last* element matching a selector
+            // because that's the rule that applies. Thus, rposition
+            self.keyframesrule.read()
+                .keyframes.iter().rposition(|frame| {
+                    frame.read().selector == sel
+                })
+        } else {
+            None
+        }
+    }
 }
 
 impl CSSKeyframesRuleMethods for CSSKeyframesRule {
@@ -59,6 +79,33 @@ impl CSSKeyframesRuleMethods for CSSKeyframesRule {
     fn CssRules(&self) -> Root<CSSRuleList> {
         self.rulelist()
     }
+
+    // https://drafts.csswg.org/css-animations/#dom-csskeyframesrule-appendrule
+    fn AppendRule(&self, rule: DOMString) {
+        let global = self.global();
+        let window = global.as_window();
+        let doc = window.Document();
+        let rule = Keyframe::parse(&rule, Origin::Author, doc.url().clone(),
+                                   ParserContextExtraData::default());
+        if let Ok(rule) = rule {
+            self.keyframesrule.write().keyframes.push(rule);
+            self.rulelist().append_lazy_dom_rule();
+        }
+    }
+
+    // https://drafts.csswg.org/css-animations/#dom-csskeyframesrule-deleterule
+    fn DeleteRule(&self, selector: DOMString) {
+        if let Some(idx) = self.find_rule(&selector) {
+            let _ = self.rulelist().remove_rule(idx as u32);
+        }
+    }
+
+    // https://drafts.csswg.org/css-animations/#dom-csskeyframesrule-findrule
+    fn FindRule(&self, selector: DOMString) -> Option<Root<CSSKeyframeRule>> {
+        self.find_rule(&selector).and_then(|idx| {
+            self.rulelist().item(idx as u32)
+        }).and_then(Root::downcast)
+    }
 }
 
 impl SpecificCSSRule for CSSKeyframesRule {