LibWeb: Implement VideoTrack and VideoTrackList

This implements the IDL for these types and some event handling around
them.

9 files changed, 365 insertions, 1 deletions

diff --git a/Userland/Libraries/LibWeb/CMakeLists.txt b/Userland/Libraries/LibWeb/CMakeLists.txt
index 90dcae1ba8..eb04197fe8 100644
--- a/Userland/Libraries/LibWeb/CMakeLists.txt
+++ b/Userland/Libraries/LibWeb/CMakeLists.txt
@@ -343,6 +343,8 @@ set(SOURCES
     HTML/TagNames.cpp
     HTML/TextMetrics.cpp
     HTML/Timer.cpp
+    HTML/VideoTrack.cpp
+    HTML/VideoTrackList.cpp
     HTML/Window.cpp
     HTML/WindowEventHandlers.cpp
     HTML/WindowOrWorkerGlobalScope.cpp
@@ -547,7 +549,7 @@ set(GENERATED_SOURCES
 serenity_lib(LibWeb web)
 
 # NOTE: We link with LibSoftGPU here instead of lazy loading it via dlopen() so that we do not have to unveil the library and pledge prot_exec.
-target_link_libraries(LibWeb PRIVATE LibCore LibCrypto LibJS LibMarkdown LibHTTP LibGemini LibGL LibGUI LibGfx LibIPC LibLocale LibRegex LibSoftGPU LibSyntax LibTextCodec LibUnicode LibWasm LibXML LibIDL)
+target_link_libraries(LibWeb PRIVATE LibCore LibCrypto LibJS LibMarkdown LibHTTP LibGemini LibGL LibGUI LibGfx LibIPC LibLocale LibRegex LibSoftGPU LibSyntax LibTextCodec LibUnicode LibVideo LibWasm LibXML LibIDL)
 link_with_locale_data(LibWeb)
 
 generate_js_bindings(LibWeb)
diff --git a/Userland/Libraries/LibWeb/Forward.h b/Userland/Libraries/LibWeb/Forward.h
index cf900b0de2..2d17e90bea 100644
--- a/Userland/Libraries/LibWeb/Forward.h
+++ b/Userland/Libraries/LibWeb/Forward.h
@@ -355,6 +355,8 @@ class Storage;
 class SubmitEvent;
 class TextMetrics;
 class Timer;
+class VideoTrack;
+class VideoTrackList;
 class Window;
 class WindowEnvironmentSettingsObject;
 class WindowProxy;
diff --git a/Userland/Libraries/LibWeb/HTML/VideoTrack.cpp b/Userland/Libraries/LibWeb/HTML/VideoTrack.cpp
new file mode 100644
index 0000000000..14983a2284
--- /dev/null
+++ b/Userland/Libraries/LibWeb/HTML/VideoTrack.cpp
@@ -0,0 +1,88 @@
+/*
+ * Copyright (c) 2023, Tim Flynn <trflynn89@serenityos.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include <AK/IDAllocator.h>
+#include <LibJS/Runtime/Realm.h>
+#include <LibJS/Runtime/VM.h>
+#include <LibWeb/Bindings/Intrinsics.h>
+#include <LibWeb/Bindings/VideoTrackPrototype.h>
+#include <LibWeb/DOM/Event.h>
+#include <LibWeb/HTML/EventNames.h>
+#include <LibWeb/HTML/HTMLMediaElement.h>
+#include <LibWeb/HTML/VideoTrack.h>
+#include <LibWeb/HTML/VideoTrackList.h>
+
+namespace Web::HTML {
+
+static IDAllocator s_video_track_id_allocator;
+
+VideoTrack::VideoTrack(JS::Realm& realm, JS::NonnullGCPtr<HTMLMediaElement> media_element, NonnullOwnPtr<Video::Matroska::MatroskaDemuxer> demuxer, Video::Track track)
+    : PlatformObject(realm)
+    , m_media_element(media_element)
+    , m_demuxer(move(demuxer))
+    , m_track(track)
+{
+}
+
+VideoTrack::~VideoTrack()
+{
+    auto id = m_id.to_number<int>();
+    VERIFY(id.has_value());
+
+    s_video_track_id_allocator.deallocate(id.value());
+}
+
+JS::ThrowCompletionOr<void> VideoTrack::initialize(JS::Realm& realm)
+{
+    MUST_OR_THROW_OOM(Base::initialize(realm));
+    set_prototype(&Bindings::ensure_web_prototype<Bindings::VideoTrackPrototype>(realm, "VideoTrack"));
+
+    auto id = s_video_track_id_allocator.allocate();
+    m_id = TRY_OR_THROW_OOM(realm.vm(), String::number(id));
+
+    return {};
+}
+
+void VideoTrack::visit_edges(Cell::Visitor& visitor)
+{
+    visitor.visit(m_media_element);
+    visitor.visit(m_video_track_list);
+}
+
+// https://html.spec.whatwg.org/multipage/media.html#dom-videotrack-selected
+void VideoTrack::set_selected(bool selected)
+{
+    // On setting, it must select the track if the new value is true, and unselect it otherwise.
+    if (m_selected == selected)
+        return;
+
+    // If the track is in a VideoTrackList, then all the other VideoTrack objects in that list must be unselected. (If the track is
+    // no longer in a VideoTrackList object, then the track being selected or unselected has no effect beyond changing the value of
+    // the attribute on the VideoTrack object.)
+    if (m_video_track_list) {
+        for (auto video_track : m_video_track_list->video_tracks({})) {
+            if (video_track.ptr() != this)
+                video_track->m_selected = false;
+        }
+
+        // Whenever a track in a VideoTrackList that was previously not selected is selected, and whenever the selected track in a
+        // VideoTrackList is unselected without a new track being selected in its stead, the user agent must queue a media element
+        // task given the media element to fire an event named change at the VideoTrackList object. This task must be queued before
+        // the task that fires the resize event, if any.
+        auto previously_unselected_track_is_selected = !m_selected && selected;
+        auto selected_track_was_unselected_without_another_selection = m_selected && !selected;
+
+        if (previously_unselected_track_is_selected || selected_track_was_unselected_without_another_selection) {
+            m_media_element->queue_a_media_element_task([this]() {
+                m_video_track_list->dispatch_event(DOM::Event::create(realm(), HTML::EventNames::change.to_deprecated_fly_string()).release_value_but_fixme_should_propagate_errors());
+            });
+        }
+    }
+
+    m_selected = selected;
+}
+
+}
diff --git a/Userland/Libraries/LibWeb/HTML/VideoTrack.h b/Userland/Libraries/LibWeb/HTML/VideoTrack.h
new file mode 100644
index 0000000000..4f2264dba7
--- /dev/null
+++ b/Userland/Libraries/LibWeb/HTML/VideoTrack.h
@@ -0,0 +1,65 @@
+/*
+ * Copyright (c) 2023, Tim Flynn <trflynn89@serenityos.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#pragma once
+
+#include <AK/String.h>
+#include <AK/Time.h>
+#include <LibVideo/Containers/Matroska/MatroskaDemuxer.h>
+#include <LibVideo/Track.h>
+#include <LibWeb/Bindings/PlatformObject.h>
+
+namespace Web::HTML {
+
+class VideoTrack final : public Bindings::PlatformObject {
+    WEB_PLATFORM_OBJECT(VideoTrack, Bindings::PlatformObject);
+
+public:
+    virtual ~VideoTrack() override;
+
+    void set_video_track_list(Badge<VideoTrackList>, JS::GCPtr<VideoTrackList> video_track_list) { m_video_track_list = video_track_list; }
+
+    Time duration() const { return m_track.video_data().duration; }
+    u64 pixel_width() const { return m_track.video_data().pixel_width; }
+    u64 pixel_height() const { return m_track.video_data().pixel_height; }
+
+    String const& id() const { return m_id; }
+    String const& kind() const { return m_kind; }
+    String const& label() const { return m_label; }
+    String const& language() const { return m_language; }
+
+    bool selected() const { return m_selected; }
+    void set_selected(bool selected);
+
+private:
+    explicit VideoTrack(JS::Realm&, JS::NonnullGCPtr<HTMLMediaElement>, NonnullOwnPtr<Video::Matroska::MatroskaDemuxer>, Video::Track);
+
+    virtual JS::ThrowCompletionOr<void> initialize(JS::Realm&) override;
+    virtual void visit_edges(Cell::Visitor&) override;
+
+    // https://html.spec.whatwg.org/multipage/media.html#dom-videotrack-id
+    String m_id;
+
+    // https://html.spec.whatwg.org/multipage/media.html#dom-videotrack-kind
+    String m_kind;
+
+    // https://html.spec.whatwg.org/multipage/media.html#dom-videotrack-label
+    String m_label;
+
+    // https://html.spec.whatwg.org/multipage/media.html#dom-videotrack-language
+    String m_language;
+
+    // https://html.spec.whatwg.org/multipage/media.html#dom-videotrack-selected
+    bool m_selected { false };
+
+    JS::NonnullGCPtr<HTMLMediaElement> m_media_element;
+    JS::GCPtr<VideoTrackList> m_video_track_list;
+
+    NonnullOwnPtr<Video::Matroska::MatroskaDemuxer> m_demuxer;
+    Video::Track m_track;
+};
+
+}
diff --git a/Userland/Libraries/LibWeb/HTML/VideoTrack.idl b/Userland/Libraries/LibWeb/HTML/VideoTrack.idl
new file mode 100644
index 0000000000..00036a865b
--- /dev/null
+++ b/Userland/Libraries/LibWeb/HTML/VideoTrack.idl
@@ -0,0 +1,9 @@
+// https://html.spec.whatwg.org/multipage/media.html#videotrack
+[Exposed=Window]
+interface VideoTrack {
+    readonly attribute DOMString id;
+    readonly attribute DOMString kind;
+    readonly attribute DOMString label;
+    readonly attribute DOMString language;
+    attribute boolean selected;
+};
diff --git a/Userland/Libraries/LibWeb/HTML/VideoTrackList.cpp b/Userland/Libraries/LibWeb/HTML/VideoTrackList.cpp
new file mode 100644
index 0000000000..f590c9fedc
--- /dev/null
+++ b/Userland/Libraries/LibWeb/HTML/VideoTrackList.cpp
@@ -0,0 +1,130 @@
+/*
+ * Copyright (c) 2023, Tim Flynn <trflynn89@serenityos.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include <LibJS/Runtime/Realm.h>
+#include <LibJS/Runtime/VM.h>
+#include <LibWeb/Bindings/Intrinsics.h>
+#include <LibWeb/Bindings/VideoTrackListPrototype.h>
+#include <LibWeb/HTML/EventNames.h>
+#include <LibWeb/HTML/VideoTrackList.h>
+
+namespace Web::HTML {
+
+VideoTrackList::VideoTrackList(JS::Realm& realm)
+    : DOM::EventTarget(realm)
+    , m_video_tracks(realm.heap())
+{
+}
+
+JS::ThrowCompletionOr<void> VideoTrackList::initialize(JS::Realm& realm)
+{
+    MUST_OR_THROW_OOM(Base::initialize(realm));
+    set_prototype(&Bindings::ensure_web_prototype<Bindings::VideoTrackListPrototype>(realm, "VideoTrackList"));
+
+    return {};
+}
+
+// https://html.spec.whatwg.org/multipage/media.html#dom-tracklist-item
+JS::ThrowCompletionOr<Optional<JS::PropertyDescriptor>> VideoTrackList::internal_get_own_property(JS::PropertyKey const& property_name) const
+{
+    // To determine the value of an indexed property for a given index index in an AudioTrackList or VideoTrackList
+    // object list, the user agent must return the AudioTrack or VideoTrack object that represents the indexth track
+    // in list.
+    if (property_name.is_number()) {
+        if (auto index = property_name.as_number(); index < m_video_tracks.size()) {
+            JS::PropertyDescriptor descriptor;
+            descriptor.value = m_video_tracks.at(index);
+
+            return descriptor;
+        }
+    }
+
+    return Base::internal_get_own_property(property_name);
+}
+
+ErrorOr<void> VideoTrackList::add_track(Badge<HTMLMediaElement>, JS::NonnullGCPtr<VideoTrack> video_track)
+{
+    TRY(m_video_tracks.try_append(video_track));
+    video_track->set_video_track_list({}, this);
+
+    return {};
+}
+
+void VideoTrackList::remove_all_tracks(Badge<HTMLMediaElement>)
+{
+    m_video_tracks.clear();
+}
+
+// https://html.spec.whatwg.org/multipage/media.html#dom-videotracklist-gettrackbyid
+JS::GCPtr<VideoTrack> VideoTrackList::get_track_by_id(StringView id) const
+{
+    // The AudioTrackList getTrackById(id) and VideoTrackList getTrackById(id) methods must return the first AudioTrack
+    // or VideoTrack object (respectively) in the AudioTrackList or VideoTrackList object (respectively) whose identifier
+    // is equal to the value of the id argument (in the natural order of the list, as defined above).
+    auto it = m_video_tracks.find_if([&](auto const& video_track) {
+        return video_track->id() == id;
+    });
+
+    // When no tracks match the given argument, the methods must return null.
+    if (it == m_video_tracks.end())
+        return nullptr;
+
+    return *it;
+}
+
+// https://html.spec.whatwg.org/multipage/media.html#dom-videotracklist-selectedindex
+i32 VideoTrackList::selected_index() const
+{
+    // The VideoTrackList selectedIndex attribute must return the index of the currently selected track, if any.
+    auto it = m_video_tracks.find_if([&](auto const& video_track) {
+        return video_track->selected();
+    });
+
+    // If the VideoTrackList object does not currently represent any tracks, or if none of the tracks are selected,
+    // it must instead return −1.
+    if (it == m_video_tracks.end())
+        return -1;
+
+    return static_cast<i32>(it.index());
+}
+
+// https://html.spec.whatwg.org/multipage/media.html#handler-tracklist-onchange
+void VideoTrackList::set_onchange(WebIDL::CallbackType* event_handler)
+{
+    set_event_handler_attribute(HTML::EventNames::change, event_handler);
+}
+
+// https://html.spec.whatwg.org/multipage/media.html#handler-tracklist-onchange
+WebIDL::CallbackType* VideoTrackList::onchange()
+{
+    return event_handler_attribute(HTML::EventNames::change);
+}
+
+// https://html.spec.whatwg.org/multipage/media.html#handler-tracklist-onaddtrack
+void VideoTrackList::set_onaddtrack(WebIDL::CallbackType* event_handler)
+{
+    set_event_handler_attribute(HTML::EventNames::addtrack, event_handler);
+}
+
+// https://html.spec.whatwg.org/multipage/media.html#handler-tracklist-onaddtrack
+WebIDL::CallbackType* VideoTrackList::onaddtrack()
+{
+    return event_handler_attribute(HTML::EventNames::addtrack);
+}
+
+// https://html.spec.whatwg.org/multipage/media.html#handler-tracklist-onremovetrack
+void VideoTrackList::set_onremovetrack(WebIDL::CallbackType* event_handler)
+{
+    set_event_handler_attribute(HTML::EventNames::removetrack, event_handler);
+}
+
+// https://html.spec.whatwg.org/multipage/media.html#handler-tracklist-onremovetrack
+WebIDL::CallbackType* VideoTrackList::onremovetrack()
+{
+    return event_handler_attribute(HTML::EventNames::removetrack);
+}
+
+}
diff --git a/Userland/Libraries/LibWeb/HTML/VideoTrackList.h b/Userland/Libraries/LibWeb/HTML/VideoTrackList.h
new file mode 100644
index 0000000000..d0f9732d12
--- /dev/null
+++ b/Userland/Libraries/LibWeb/HTML/VideoTrackList.h
@@ -0,0 +1,50 @@
+/*
+ * Copyright (c) 2023, Tim Flynn <trflynn89@serenityos.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#pragma once
+
+#include <AK/Badge.h>
+#include <AK/String.h>
+#include <LibJS/Heap/MarkedVector.h>
+#include <LibWeb/DOM/EventTarget.h>
+#include <LibWeb/HTML/VideoTrack.h>
+
+namespace Web::HTML {
+
+class VideoTrackList final : public DOM::EventTarget {
+    WEB_PLATFORM_OBJECT(VideoTrackList, DOM::EventTarget);
+
+public:
+    ErrorOr<void> add_track(Badge<HTMLMediaElement>, JS::NonnullGCPtr<VideoTrack>);
+    void remove_all_tracks(Badge<HTMLMediaElement>);
+
+    Span<JS::NonnullGCPtr<VideoTrack>> video_tracks(Badge<VideoTrack>) { return m_video_tracks; }
+
+    // https://html.spec.whatwg.org/multipage/media.html#dom-videotracklist-length
+    size_t length() const { return m_video_tracks.size(); }
+
+    JS::GCPtr<VideoTrack> get_track_by_id(StringView id) const;
+    i32 selected_index() const;
+
+    void set_onchange(WebIDL::CallbackType*);
+    WebIDL::CallbackType* onchange();
+
+    void set_onaddtrack(WebIDL::CallbackType*);
+    WebIDL::CallbackType* onaddtrack();
+
+    void set_onremovetrack(WebIDL::CallbackType*);
+    WebIDL::CallbackType* onremovetrack();
+
+private:
+    explicit VideoTrackList(JS::Realm&);
+
+    virtual JS::ThrowCompletionOr<void> initialize(JS::Realm&) override;
+    virtual JS::ThrowCompletionOr<Optional<JS::PropertyDescriptor>> internal_get_own_property(JS::PropertyKey const& property_name) const override;
+
+    JS::MarkedVector<JS::NonnullGCPtr<VideoTrack>> m_video_tracks;
+};
+
+}
diff --git a/Userland/Libraries/LibWeb/HTML/VideoTrackList.idl b/Userland/Libraries/LibWeb/HTML/VideoTrackList.idl
new file mode 100644
index 0000000000..3c54de0c17
--- /dev/null
+++ b/Userland/Libraries/LibWeb/HTML/VideoTrackList.idl
@@ -0,0 +1,16 @@
+#import <DOM/EventHandler.idl>
+#import <DOM/EventTarget.idl>
+#import <HTML/VideoTrack.idl>
+
+// https://html.spec.whatwg.org/multipage/media.html#videotracklist
+[Exposed=Window]
+interface VideoTrackList : EventTarget {
+    readonly attribute unsigned long length;
+    getter VideoTrack (unsigned long index);
+    VideoTrack? getTrackById(DOMString id);
+    readonly attribute long selectedIndex;
+
+    attribute EventHandler onchange;
+    attribute EventHandler onaddtrack;
+    attribute EventHandler onremovetrack;
+};
diff --git a/Userland/Libraries/LibWeb/idl_files.cmake b/Userland/Libraries/LibWeb/idl_files.cmake
index 3f4461e2c0..55d4d84dda 100644
--- a/Userland/Libraries/LibWeb/idl_files.cmake
+++ b/Userland/Libraries/LibWeb/idl_files.cmake
@@ -165,6 +165,8 @@ libweb_js_bindings(HTML/PromiseRejectionEvent)
 libweb_js_bindings(HTML/Storage)
 libweb_js_bindings(HTML/SubmitEvent)
 libweb_js_bindings(HTML/TextMetrics)
+libweb_js_bindings(HTML/VideoTrack)
+libweb_js_bindings(HTML/VideoTrackList)
 libweb_js_bindings(HTML/Window GLOBAL)
 libweb_js_bindings(HTML/Worker)
 libweb_js_bindings(HTML/WorkerGlobalScope)