Media fragment parser

7 files changed, 464 insertions, 11 deletions

diff --git a/components/script/dom/audiotrack.rs b/components/script/dom/audiotrack.rs
index 9233b1d9c93..6a43eed64b2 100644
--- a/components/script/dom/audiotrack.rs
+++ b/components/script/dom/audiotrack.rs
@@ -55,6 +55,10 @@ impl AudioTrack {
         self.id.clone()
     }
 
+    pub fn kind(&self) -> DOMString {
+        self.kind.clone()
+    }
+
     pub fn enabled(&self) -> bool {
         self.enabled.get()
     }
@@ -72,7 +76,7 @@ impl AudioTrackMethods for AudioTrack {
 
     // https://html.spec.whatwg.org/multipage/#dom-audiotrack-kind
     fn Kind(&self) -> DOMString {
-        self.kind.clone()
+        self.kind()
     }
 
     // https://html.spec.whatwg.org/multipage/#dom-audiotrack-label
diff --git a/components/script/dom/htmlmediaelement.rs b/components/script/dom/htmlmediaelement.rs
index 9ba07fe0c09..4abd9d6823a 100644
--- a/components/script/dom/htmlmediaelement.rs
+++ b/components/script/dom/htmlmediaelement.rs
@@ -41,6 +41,7 @@ use crate::dom::htmlelement::HTMLElement;
 use crate::dom::htmlsourceelement::HTMLSourceElement;
 use crate::dom::htmlvideoelement::HTMLVideoElement;
 use crate::dom::mediaerror::MediaError;
+use crate::dom::mediafragmentparser::MediaFragmentParser;
 use crate::dom::mediastream::MediaStream;
 use crate::dom::node::{document_from_node, window_from_node, Node, NodeDamage, UnbindContext};
 use crate::dom::performanceresourcetiming::InitiatorType;
@@ -1511,8 +1512,20 @@ impl HTMLMediaElement {
                         self.AudioTracks().add(&audio_track);
 
                         // Step 4
-                        // https://www.w3.org/TR/media-frags/#media-fragment-syntax
-                        // https://github.com/servo/servo/issues/22366
+                        if let Some(servo_url) = self.resource_url.borrow().as_ref() {
+                            let fragment = MediaFragmentParser::from(servo_url);
+                            if let Some(id) = fragment.id() {
+                                if audio_track.id() == id {
+                                    self.AudioTracks()
+                                        .set_enabled(self.AudioTracks().len() - 1, true);
+                                }
+                            }
+
+                            if fragment.tracks().contains(&audio_track.kind()) {
+                                self.AudioTracks()
+                                    .set_enabled(self.AudioTracks().len() - 1, true);
+                            }
+                        }
 
                         // Step 5. & 6,
                         if self.AudioTracks().enabled_index().is_none() {
@@ -1554,8 +1567,18 @@ impl HTMLMediaElement {
                         self.VideoTracks().add(&video_track);
 
                         // Step 4.
-                        // https://www.w3.org/TR/media-frags/#media-fragment-syntax
-                        // https://github.com/servo/servo/issues/22366
+                        if let Some(track) = self.VideoTracks().item(0) {
+                            if let Some(servo_url) = self.resource_url.borrow().as_ref() {
+                                let fragment = MediaFragmentParser::from(servo_url);
+                                if let Some(id) = fragment.id() {
+                                    if track.id() == id {
+                                        self.VideoTracks().set_selected(0, true);
+                                    }
+                                } else if fragment.tracks().contains(&track.kind()) {
+                                    self.VideoTracks().set_selected(0, true);
+                                }
+                            }
+                        }
 
                         // Step 5. & 6.
                         if self.VideoTracks().selected_index().is_none() {
@@ -1617,7 +1640,7 @@ impl HTMLMediaElement {
                 self.change_ready_state(ReadyState::HaveMetadata);
 
                 // Step 7.
-                let mut _jumped = false;
+                let mut jumped = false;
 
                 // Step 8.
                 if self.default_playback_start_position.get() > 0. {
@@ -1625,16 +1648,24 @@ impl HTMLMediaElement {
                         self.default_playback_start_position.get(),
                         /* approximate_for_speed*/ false,
                     );
-                    _jumped = true;
+                    jumped = true;
                 }
 
                 // Step 9.
                 self.default_playback_start_position.set(0.);
 
                 // Steps 10 and 11.
-                // XXX(ferjm) Implement parser for
-                //            https://www.w3.org/TR/media-frags/#media-fragment-syntax
-                //            https://github.com/servo/media/issues/156
+                if let Some(servo_url) = self.resource_url.borrow().as_ref() {
+                    let fragment = MediaFragmentParser::from(servo_url);
+                    if let Some(start) = fragment.start() {
+                        if start > 0. && start < self.duration.get() {
+                            self.playback_position.set(start);
+                            if !jumped {
+                                self.seek(self.playback_position.get(), false)
+                            }
+                        }
+                    }
+                }
 
                 // Step 12 & 13 are already handled by the earlier media track processing.
             },
diff --git a/components/script/dom/mediafragmentparser.rs b/components/script/dom/mediafragmentparser.rs
new file mode 100644
index 00000000000..ddd3f029df4
--- /dev/null
+++ b/components/script/dom/mediafragmentparser.rs
@@ -0,0 +1,355 @@
+/* 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/. */
+
+use crate::dom::bindings::str::DOMString;
+use chrono::NaiveDateTime;
+use servo_url::ServoUrl;
+use std::borrow::Cow;
+use std::collections::VecDeque;
+use std::str::FromStr;
+use url::{form_urlencoded, Position, Url};
+
+#[derive(Clone, Copy, Debug, Eq, PartialEq)]
+pub enum SpatialRegion {
+    Pixel,
+    Percent,
+}
+
+impl FromStr for SpatialRegion {
+    type Err = ();
+
+    fn from_str(s: &str) -> Result<Self, Self::Err> {
+        match s {
+            "pixel" => Ok(SpatialRegion::Pixel),
+            "percent" => Ok(SpatialRegion::Percent),
+            _ => Err(()),
+        }
+    }
+}
+
+#[derive(Clone, Debug, Eq, PartialEq)]
+pub struct SpatialClipping {
+    region: Option<SpatialRegion>,
+    x: u32,
+    y: u32,
+    width: u32,
+    height: u32,
+}
+
+#[derive(Clone, Debug, Default, PartialEq)]
+pub struct MediaFragmentParser {
+    id: Option<DOMString>,
+    tracks: Vec<DOMString>,
+    spatial: Option<SpatialClipping>,
+    start: Option<f64>,
+    end: Option<f64>,
+}
+
+impl MediaFragmentParser {
+    pub fn id(&self) -> Option<DOMString> {
+        self.id.clone()
+    }
+
+    pub fn tracks(&self) -> &Vec<DOMString> {
+        self.tracks.as_ref()
+    }
+
+    pub fn start(&self) -> Option<f64> {
+        self.start
+    }
+
+    // Parse an str of key value pairs, a URL, or a fragment.
+    pub fn parse(input: &str) -> MediaFragmentParser {
+        let mut parser = MediaFragmentParser::default();
+        let (query, fragment) = split_url(input);
+        let mut octets = decode_octets(query.as_bytes());
+        octets.extend(decode_octets(fragment.as_bytes()));
+
+        if !octets.is_empty() {
+            for (key, value) in octets.iter() {
+                match key.as_bytes() {
+                    b"t" => {
+                        if let Ok((start, end)) = parser.parse_temporal(value) {
+                            parser.start = start;
+                            parser.end = end;
+                        }
+                    },
+                    b"xywh" => {
+                        if let Ok(spatial) = parser.parse_spatial(value) {
+                            parser.spatial = Some(spatial);
+                        }
+                    },
+                    b"id" => parser.id = Some(DOMString::from(value.as_ref())),
+                    b"track" => parser.tracks.push(DOMString::from(value.as_ref())),
+                    _ => {},
+                }
+            }
+            parser
+        } else {
+            if let Ok((start, end)) = parser.parse_temporal(input) {
+                parser.start = start;
+                parser.end = end;
+            } else if let Ok(spatial) = parser.parse_spatial(input) {
+                parser.spatial = Some(spatial);
+            }
+            parser
+        }
+    }
+
+    // Either NPT or UTC timestamp (real world clock time).
+    fn parse_temporal(&self, input: &str) -> Result<(Option<f64>, Option<f64>), ()> {
+        let (_, fragment) = split_prefix(input);
+
+        if fragment.ends_with('Z') || fragment.ends_with("Z-") {
+            return self.parse_utc_timestamp(fragment);
+        }
+
+        if fragment.starts_with(',') || !fragment.contains(',') {
+            let sec = parse_hms(&fragment.replace(',', ""))?;
+            if fragment.starts_with(',') {
+                Ok((Some(0.), Some(sec)))
+            } else {
+                Ok((Some(sec), None))
+            }
+        } else {
+            let mut iterator = fragment.split(',');
+            let start = parse_hms(iterator.next().ok_or_else(|| ())?)?;
+            let end = parse_hms(iterator.next().ok_or_else(|| ())?)?;
+
+            if iterator.next().is_some() || start >= end {
+                return Err(());
+            }
+
+            Ok((Some(start), Some(end)))
+        }
+    }
+
+    fn parse_utc_timestamp(&self, input: &str) -> Result<(Option<f64>, Option<f64>), ()> {
+        if input.ends_with('-') || input.starts_with(',') || !input.contains('-') {
+            let sec = parse_hms(
+                NaiveDateTime::parse_from_str(
+                    &input.replace('-', "").replace(',', ""),
+                    "%Y%m%dT%H%M%S%.fZ",
+                )
+                .map_err(|_| ())?
+                .time()
+                .to_string()
+                .as_ref(),
+            )?;
+            if input.starts_with(',') {
+                Ok((Some(0.), Some(sec)))
+            } else {
+                Ok((Some(sec), None))
+            }
+        } else {
+            let vec: Vec<&str> = input.split('-').collect();
+            let mut hms: Vec<f64> = vec
+                .iter()
+                .map(|s| NaiveDateTime::parse_from_str(s, "%Y%m%dT%H%M%S%.fZ"))
+                .flatten()
+                .map(|s| parse_hms(&s.time().to_string()))
+                .flatten()
+                .collect();
+
+            let end = hms.pop().ok_or_else(|| ())?;
+            let start = hms.pop().ok_or_else(|| ())?;
+
+            if !hms.is_empty() || start >= end {
+                return Err(());
+            }
+
+            Ok((Some(start), Some(end)))
+        }
+    }
+
+    fn parse_spatial(&self, input: &str) -> Result<SpatialClipping, ()> {
+        let (prefix, s) = split_prefix(input);
+        let vec: Vec<&str> = s.split(',').collect();
+        let mut queue: VecDeque<u32> = vec.iter().map(|s| s.parse::<u32>()).flatten().collect();
+
+        let mut clipping = SpatialClipping {
+            region: None,
+            x: queue.pop_front().ok_or_else(|| ())?,
+            y: queue.pop_front().ok_or_else(|| ())?,
+            width: queue.pop_front().ok_or_else(|| ())?,
+            height: queue.pop_front().ok_or_else(|| ())?,
+        };
+
+        if !queue.is_empty() {
+            return Err(());
+        }
+
+        if let Some(s) = prefix {
+            let region = SpatialRegion::from_str(s)?;
+            if region.eq(&SpatialRegion::Percent) &&
+                (clipping.x + clipping.width > 100 || clipping.y + clipping.height > 100)
+            {
+                return Err(());
+            }
+            clipping.region = Some(region);
+        }
+
+        Ok(clipping)
+    }
+}
+
+impl From<&Url> for MediaFragmentParser {
+    fn from(url: &Url) -> Self {
+        let input: &str = &url[Position::AfterPath..];
+        MediaFragmentParser::parse(input)
+    }
+}
+
+impl From<&ServoUrl> for MediaFragmentParser {
+    fn from(servo_url: &ServoUrl) -> Self {
+        let input: &str = &servo_url[Position::AfterPath..];
+        MediaFragmentParser::parse(input)
+    }
+}
+
+// 5.1.1 Processing name-value components.
+fn decode_octets(bytes: &[u8]) -> Vec<(Cow<str>, Cow<str>)> {
+    form_urlencoded::parse(bytes)
+        .filter(|(key, _)| match key.as_bytes() {
+            b"t" | b"track" | b"id" | b"xywh" => true,
+            _ => false,
+        })
+        .collect()
+}
+
+// Parse a full URL or a relative URL without a base retaining the query and/or fragment.
+fn split_url(s: &str) -> (DOMString, DOMString) {
+    if s.contains('?') || s.contains('#') {
+        let mut query = DOMString::new();
+        let mut fragment = DOMString::new();
+
+        for (index, byte) in s.bytes().enumerate() {
+            if byte == b'?' {
+                let mut found = false;
+                let partial = &s[index + 1..];
+                for (i, byte) in partial.bytes().enumerate() {
+                    if byte == b'#' {
+                        found = true;
+                        query.push_str(&partial[..i]);
+                        fragment.push_str(&partial[i + 1..]);
+                    }
+                }
+                if found {
+                    break;
+                } else {
+                    query.push_str(partial);
+                    break;
+                }
+            }
+
+            if byte == b'#' {
+                fragment.push_str(&s[index + 1..]);
+                break;
+            }
+        }
+        (query, fragment)
+    } else {
+        (DOMString::new(), DOMString::from(s))
+    }
+}
+
+fn is_byte_number(byte: u8) -> bool {
+    match byte {
+        48 | 49 | 50 | 51 | 52 | 53 | 54 | 55 | 56 | 57 => true,
+        _ => false,
+    }
+}
+
+fn split_prefix(s: &str) -> (Option<&str>, &str) {
+    for (index, byte) in s.bytes().enumerate() {
+        if index == 0 && is_byte_number(byte) {
+            break;
+        }
+
+        if byte == b':' {
+            return (Some(&s[..index]), &s[index + 1..]);
+        }
+    }
+    (None, s)
+}
+
+fn hms_to_seconds(hour: u32, minutes: u32, seconds: f64) -> f64 {
+    let mut sec: f64 = f64::from(hour) * 3600.;
+    sec += f64::from(minutes) * 60.;
+    sec += seconds;
+    sec
+}
+
+fn parse_npt_minute(s: &str) -> Result<u32, ()> {
+    if s.len() > 2 {
+        return Err(());
+    }
+
+    let minute = s.parse().map_err(|_| ())?;
+    if minute > 59 {
+        return Err(());
+    }
+
+    Ok(minute)
+}
+
+fn parse_npt_seconds(s: &str) -> Result<f64, ()> {
+    if s.contains('.') {
+        let mut iterator = s.split('.');
+        if let Some(s) = iterator.next() {
+            if s.len() > 2 {
+                return Err(());
+            }
+            let sec = s.parse::<u32>().map_err(|_| ())?;
+            if sec > 59 {
+                return Err(());
+            }
+        }
+
+        let _ = iterator.next();
+        if iterator.next().is_some() {
+            return Err(());
+        }
+    }
+
+    s.parse().map_err(|_| ())
+}
+
+fn parse_hms(s: &str) -> Result<f64, ()> {
+    let mut vec: VecDeque<&str> = s.split(':').collect();
+    vec.retain(|x| !x.eq(&""));
+
+    let result = match vec.len() {
+        1 => {
+            let secs = vec
+                .pop_front()
+                .ok_or_else(|| ())?
+                .parse::<f64>()
+                .map_err(|_| ())?;
+
+            if secs == 0. {
+                return Err(());
+            }
+
+            hms_to_seconds(0, 0, secs)
+        },
+        2 => hms_to_seconds(
+            0,
+            parse_npt_minute(vec.pop_front().ok_or_else(|| ())?)?,
+            parse_npt_seconds(vec.pop_front().ok_or_else(|| ())?)?,
+        ),
+        3 => hms_to_seconds(
+            vec.pop_front().ok_or_else(|| ())?.parse().map_err(|_| ())?,
+            parse_npt_minute(vec.pop_front().ok_or_else(|| ())?)?,
+            parse_npt_seconds(vec.pop_front().ok_or_else(|| ())?)?,
+        ),
+        _ => return Err(()),
+    };
+
+    if !vec.is_empty() {
+        return Err(());
+    }
+
+    Ok(result)
+}
diff --git a/components/script/dom/mod.rs b/components/script/dom/mod.rs
index d20b68c92b7..8ae0047d9df 100644
--- a/components/script/dom/mod.rs
+++ b/components/script/dom/mod.rs
@@ -396,6 +396,7 @@ pub mod keyboardevent;
 pub mod location;
 pub mod mediadevices;
 pub mod mediaerror;
+pub mod mediafragmentparser;
 pub mod medialist;
 pub mod mediaquerylist;
 pub mod mediaquerylistevent;
diff --git a/components/script/dom/videotrack.rs b/components/script/dom/videotrack.rs
index fd337db5e8a..5dc13c09645 100644
--- a/components/script/dom/videotrack.rs
+++ b/components/script/dom/videotrack.rs
@@ -55,6 +55,10 @@ impl VideoTrack {
         self.id.clone()
     }
 
+    pub fn kind(&self) -> DOMString {
+        self.kind.clone()
+    }
+
     pub fn selected(&self) -> bool {
         self.selected.get().clone()
     }
@@ -72,7 +76,7 @@ impl VideoTrackMethods for VideoTrack {
 
     // https://html.spec.whatwg.org/multipage/#dom-videotrack-kind
     fn Kind(&self) -> DOMString {
-        self.kind.clone()
+        self.kind()
     }
 
     // https://html.spec.whatwg.org/multipage/#dom-videotrack-label
diff --git a/tests/wpt/metadata/MANIFEST.json b/tests/wpt/metadata/MANIFEST.json
index ea546a88006..1264bd701bd 100644
--- a/tests/wpt/metadata/MANIFEST.json
+++ b/tests/wpt/metadata/MANIFEST.json
@@ -348626,6 +348626,12 @@
      {}
     ]
    ],
+   "html/semantics/embedded-content/media-elements/media_fragment_seek.html": [
+    [
+     "html/semantics/embedded-content/media-elements/media_fragment_seek.html",
+     {}
+    ]
+   ],
    "html/semantics/embedded-content/media-elements/mime-types/canPlayType.html": [
     [
      "html/semantics/embedded-content/media-elements/mime-types/canPlayType.html",
@@ -626132,6 +626138,10 @@
    "cd1ebb9e492673feb095a227e7ca04ceae7643b9",
    "testharness"
   ],
+  "html/semantics/embedded-content/media-elements/media_fragment_seek.html": [
+   "d6f6e6c30bf89cbb87c7fbab1529973aa69b03f6",
+   "testharness"
+  ],
   "html/semantics/embedded-content/media-elements/mime-types/canPlayType.html": [
    "56edf25aa8fb93c66fbbad5bbfb2e9652e7297d0",
    "testharness"
diff --git a/tests/wpt/web-platform-tests/html/semantics/embedded-content/media-elements/media_fragment_seek.html b/tests/wpt/web-platform-tests/html/semantics/embedded-content/media-elements/media_fragment_seek.html
new file mode 100644
index 00000000000..d6f6e6c30bf
--- /dev/null
+++ b/tests/wpt/web-platform-tests/html/semantics/embedded-content/media-elements/media_fragment_seek.html
@@ -0,0 +1,48 @@
+<!doctype html>
+<meta charset="utf-8">
+<title>Video should seek to time specified in media fragment syntax</title>
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<script src="/common/media.js"></script>
+<div id="log"></div>
+<video id="video"></video>
+<script>
+async_test(function () {
+  let video = document.getElementById("video");
+  video.src = getVideoURI('/media/movie_5') + "#t=4,7";
+  video.load();
+  this.step_timeout(function () {
+    assert_equals(video.currentTime, 4.0);
+
+    video.src = getVideoURI('/media/movie_5') + "#t=%6Ept:3";
+    video.load();
+    this.step_timeout(function () {
+      assert_true(video.src.endsWith("t=%6Ept:3"));
+      assert_equals(video.currentTime, 3.0);
+
+      video.src = getVideoURI('/media/movie_5') + "#t=00:00:01.00";
+      video.load();
+      this.step_timeout(function () {
+        assert_true(video.src.endsWith("t=00:00:01.00"));
+        assert_equals(video.currentTime, 1.0);
+
+        video.src = getVideoURI('/media/movie_5') + "#u=12&t=3";
+        video.load();
+        this.step_timeout(function () {
+          assert_true(video.src.endsWith("#u=12&t=3"));
+          assert_equals(video.currentTime, 3.0);
+
+          video.src = getVideoURI('/media/movie_5') + "#t=npt%3A3";
+          video.load();
+          this.step_timeout(function () {
+            assert_true(video.src.endsWith("t=npt%3A3"));
+            assert_equals(video.currentTime, 3.0);
+            this.done();
+          }, 1000);
+        }, 1000);
+      }, 1000);
+    }, 1000);
+  }, 1000);
+});
+</script>
+