script: Create structures for TextTrack API

Fill out the basics for the WebIDLs for the following:

  - TextTrack
  - TextTrackCue
  - TextTrackCueList
  - TextTrackList

1 files changed, 37 insertions, 0 deletions

diff --git a/components/script/dom/htmlmediaelement.rs b/components/script/dom/htmlmediaelement.rs
index d78cf8cb8f9..bbdea90dee9 100644
--- a/components/script/dom/htmlmediaelement.rs
+++ b/components/script/dom/htmlmediaelement.rs
@@ -12,6 +12,7 @@ use crate::dom::bindings::codegen::Bindings::HTMLMediaElementBinding::HTMLMediaE
 use crate::dom::bindings::codegen::Bindings::HTMLSourceElementBinding::HTMLSourceElementMethods;
 use crate::dom::bindings::codegen::Bindings::MediaErrorBinding::MediaErrorConstants::*;
 use crate::dom::bindings::codegen::Bindings::MediaErrorBinding::MediaErrorMethods;
+use crate::dom::bindings::codegen::Bindings::TextTrackBinding::{TextTrackKind, TextTrackMode};
 use crate::dom::bindings::codegen::InheritTypes::{ElementTypeId, HTMLElementTypeId};
 use crate::dom::bindings::codegen::InheritTypes::{HTMLMediaElementTypeId, NodeTypeId};
 use crate::dom::bindings::error::{Error, ErrorResult};
@@ -33,6 +34,8 @@ use crate::dom::mediaerror::MediaError;
 use crate::dom::node::{document_from_node, window_from_node, Node, NodeDamage, UnbindContext};
 use crate::dom::performanceresourcetiming::InitiatorType;
 use crate::dom::promise::Promise;
+use crate::dom::texttrack::TextTrack;
+use crate::dom::texttracklist::TextTrackList;
 use crate::dom::timeranges::{TimeRanges, TimeRangesContainer};
 use crate::dom::virtualmethods::VirtualMethods;
 use crate::fetch::FetchCanceller;
@@ -191,6 +194,8 @@ pub struct HTMLMediaElement {
     /// https://html.spec.whatwg.org/multipage/#dom-media-played
     #[ignore_malloc_size_of = "Rc"]
     played: Rc<DomRefCell<TimeRangesContainer>>,
+    /// https://html.spec.whatwg.org/multipage/#dom-media-texttracks
+    text_tracks_list: MutNullableDom<TextTrackList>,
 }
 
 /// <https://html.spec.whatwg.org/multipage/#dom-media-networkstate>
@@ -243,6 +248,7 @@ impl HTMLMediaElement {
             seeking: Cell::new(false),
             resource_url: DomRefCell::new(None),
             played: Rc::new(DomRefCell::new(TimeRangesContainer::new())),
+            text_tracks_list: Default::default(),
         }
     }
 
@@ -1376,6 +1382,37 @@ impl HTMLMediaElementMethods for HTMLMediaElement {
     fn Played(&self) -> DomRoot<TimeRanges> {
         TimeRanges::new(self.global().as_window(), self.played.clone())
     }
+
+    // https://html.spec.whatwg.org/multipage/#dom-media-texttracks
+    fn TextTracks(&self) -> DomRoot<TextTrackList> {
+        let window = window_from_node(self);
+        self.text_tracks_list
+            .or_init(|| TextTrackList::new(&window, &[]))
+    }
+
+    // https://html.spec.whatwg.org/multipage/#dom-media-addtexttrack
+    fn AddTextTrack(
+        &self,
+        kind: TextTrackKind,
+        label: DOMString,
+        language: DOMString,
+    ) -> DomRoot<TextTrack> {
+        let window = window_from_node(self);
+        // Step 1 & 2
+        // FIXME(#22314, dlrobertson) set the ready state to Loaded
+        let track = TextTrack::new(
+            &window,
+            "".into(),
+            kind,
+            label,
+            language,
+            TextTrackMode::Hidden,
+        );
+        // Step 3 & 4
+        self.TextTracks().add(&track);
+        // Step 5
+        DomRoot::from_ref(&track)
+    }
 }
 
 impl VirtualMethods for HTMLMediaElement {