Auto merge of #12186 - GuillaumeGomez:video-metadata, r=larsbergstrom,jdm,KiChjang

Implement video-metadata check

<!-- Reviewable:start -->
This change is [<img src="https://reviewable.io/review_button.svg" height="35" align="absmiddle" alt="Reviewable"/>](https://reviewable.io/reviews/servo/servo/12186)
<!-- Reviewable:end -->

2 files changed, 49 insertions, 7 deletions

diff --git a/components/script/dom/bindings/trace.rs b/components/script/dom/bindings/trace.rs
index 3c13572bf37..618061fe769 100644
--- a/components/script/dom/bindings/trace.rs
+++ b/components/script/dom/bindings/trace.rs
@@ -91,6 +91,7 @@ use style::element_state::*;
 use style::properties::PropertyDeclarationBlock;
 use style::selector_impl::{PseudoElement, ElementSnapshot};
 use style::values::specified::Length;
+use time::Duration;
 use url::Origin as UrlOrigin;
 use url::Url;
 use uuid::Uuid;
@@ -109,6 +110,8 @@ no_jsmanaged_fields!(EncodingRef);
 
 no_jsmanaged_fields!(Reflector);
 
+no_jsmanaged_fields!(Duration);
+
 /// Trace a `JSVal`.
 pub fn trace_jsval(tracer: *mut JSTracer, description: &str, val: &Heap<JSVal>) {
     unsafe {
diff --git a/components/script/dom/htmlmediaelement.rs b/components/script/dom/htmlmediaelement.rs
index 7a94768c13a..119139ae6d8 100644
--- a/components/script/dom/htmlmediaelement.rs
+++ b/components/script/dom/htmlmediaelement.rs
@@ -35,6 +35,8 @@ use string_cache::Atom;
 use task_source::TaskSource;
 use time::{self, Timespec, Duration};
 use url::Url;
+#[cfg(not(any(target_os = "android", target_arch = "arm", target_arch = "aarch64")))]
+use video_metadata;
 
 struct HTMLMediaElementContext {
     /// The element that initiated the request.
@@ -75,12 +77,11 @@ impl AsyncResponseListener for HTMLMediaElementContext {
         }
     }
 
-    fn data_available(&mut self, payload: Vec<u8>) {
+    fn data_available(&mut self, mut payload: Vec<u8>) {
         if self.ignore_response {
             return;
         }
 
-        let mut payload = payload;
         self.data.append(&mut payload);
 
         let elem = self.elem.root();
@@ -88,11 +89,7 @@ impl AsyncResponseListener for HTMLMediaElementContext {
         // https://html.spec.whatwg.org/multipage/#media-data-processing-steps-list
         // => "Once enough of the media data has been fetched to determine the duration..."
         if !self.have_metadata {
-            //TODO: actually check if the payload contains the full metadata
-
-            // Step 6
-            elem.change_ready_state(HAVE_METADATA);
-            self.have_metadata = true;
+            self.check_metadata(&elem);
         } else {
             elem.change_ready_state(HAVE_CURRENT_DATA);
         }
@@ -162,6 +159,46 @@ impl HTMLMediaElementContext {
             ignore_response: false,
         }
     }
+
+    #[cfg(not(any(target_os = "android", target_arch = "arm", target_arch = "aarch64")))]
+    fn check_metadata(&mut self, elem: &HTMLMediaElement) {
+        match video_metadata::get_format_from_slice(&self.data) {
+            Ok(meta) => {
+                let dur = meta.duration.unwrap_or(::std::time::Duration::new(0, 0));
+                *elem.video.borrow_mut() = Some(VideoMedia {
+                    format: format!("{:?}", meta.format),
+                    duration: Duration::seconds(dur.as_secs() as i64) +
+                              Duration::nanoseconds(dur.subsec_nanos() as i64),
+                    width: meta.size.width,
+                    height: meta.size.height,
+                    video: meta.video,
+                    audio: meta.audio,
+                });
+                // Step 6
+                elem.change_ready_state(HAVE_METADATA);
+                self.have_metadata = true;
+            }
+            _ => {}
+        }
+    }
+
+    #[cfg(any(target_os = "android", target_arch = "arm", target_arch = "aarch64"))]
+    fn check_metadata(&mut self, elem: &HTMLMediaElement) {
+        // Step 6.
+        elem.change_ready_state(HAVE_METADATA);
+        self.have_metadata = true;
+    }
+}
+
+#[derive(JSTraceable, HeapSizeOf)]
+pub struct VideoMedia {
+    format: String,
+    #[ignore_heap_size_of = "defined in time"]
+    duration: Duration,
+    width: u32,
+    height: u32,
+    video: String,
+    audio: Option<String>,
 }
 
 #[dom_struct]
@@ -175,6 +212,7 @@ pub struct HTMLMediaElement {
     error: MutNullableHeap<JS<MediaError>>,
     paused: Cell<bool>,
     autoplaying: Cell<bool>,
+    video: DOMRefCell<Option<VideoMedia>>,
 }
 
 impl HTMLMediaElement {
@@ -192,6 +230,7 @@ impl HTMLMediaElement {
             error: Default::default(),
             paused: Cell::new(true),
             autoplaying: Cell::new(true),
+            video: DOMRefCell::new(None),
         }
     }