initial implementation of video start/end times

3 files changed, 362 insertions, 4 deletions

diff --git a/src/commands/meme.rs b/src/commands/meme.rs
index 6d50349..8514eed 100644
--- a/src/commands/meme.rs
+++ b/src/commands/meme.rs
@@ -218,6 +218,8 @@ fn send_meme(ctx: &Context, t: &Meme, conn: &PgConnection, msg: &Message) -> Res
             initiator: msg.author.name.clone(),
             data: ::either::Right(audio.data.clone()),
             sender_channel: msg.channel_id,
+            start: None,
+            end: None,
         });
     }
 
diff --git a/src/commands/playback/mod.rs b/src/commands/playback/mod.rs
index 051fabb..e5e7a4c 100644
--- a/src/commands/playback/mod.rs
+++ b/src/commands/playback/mod.rs
@@ -1,4 +1,7 @@
 use either::{Left, Right};
+use regex::Regex;
+use time::Duration;
+
 use serenity::{
     framework::standard::Args,
     model::{
@@ -46,29 +49,265 @@ impl CtxExt for Context {
 }
 
 pub fn _play(ctx: &Context, msg: &Message, url: &str) -> Result<()> {
+    use url::{Url, Host};
+
     debug!("playing '{}'", url);
     if !url.starts_with("http") {
         send(msg.channel_id, "bAD LiNk", msg.tts)?;
         return Ok(());
     }
 
-    if url.contains("imgur") {
+    let url = match Url::parse(url) {
+        Err(e) => {
+            send(msg.channel_id, "INVALID URL", msg.tts)?;
+            return Err(e.into());
+        },
+        Ok(u) => u,
+    };
+
+    let host = url.host().and_then(|u| match u {
+        Host::Domain(h) => Some(h.to_owned()),
+        _ => None,
+    });
+
+    if host.map(|h| h.to_lowercase().contains("imgur")).unwrap_or(false) {
         send(msg.channel_id, "IMGUR IS BAD, YOU TRASH CAN MAN", msg.tts)?;
         return Ok(());
     }
 
+    let (start, end) = parse_times(&msg.content);
+
     let queue_lock = ctx.data.lock().get::<PlayQueue>().cloned().unwrap();
     let mut play_queue = queue_lock.write().unwrap();
 
     play_queue.queue.push_back(PlayArgs{
         initiator: msg.author.name.clone(),
-        data: Left(url.to_owned()),
+        data: Left(url.into_string()),
         sender_channel: msg.channel_id,
+        start,
+        end,
     });
 
     Ok(())
 }
 
+lazy_static! {
+    static ref START_REGEX: Regex =
+        Regex::new(r"(?:start|begin(?:ning)?)\s*=?\s*(?:(?P<hours>\d+)h\s?)?(?:(?P<minutes>\d+)m\s?)?(?:(?P<seconds>\d+)s?)?").unwrap();
+
+    static ref DUR_REGEX: Regex =
+        Regex::new(r"dur(?:ation)?\s*=?\s*(?:(?P<hours>\d+)h\s?)?(?:(?P<minutes>\d+)m\s?)?(?:(?P<seconds>\d+)s?)?").unwrap();
+
+    static ref END_REGEX: Regex =
+        Regex::new(r"(?:end|term(?:inate|ination)?)\s*=?\s*(?:(?P<hours>\d+)h\s?)?(?:(?P<minutes>\d+)m\s?)?(?:(?P<seconds>\d+)s?)?").unwrap();
+}
+
+fn parse_times<A: AsRef<str>>(s: A) -> (Option<Duration>, Option<Duration>) {
+    use regex::Match;
+
+    fn parse_match(m: Option<Match>) -> u64 {
+        m.and_then(|s| s.as_str().parse::<u64>().ok()).unwrap_or(0)
+    }
+
+    fn parse_captures<B: AsRef<str>>(r: &Regex, s: B) -> Option<Duration> {
+        r.captures(s.as_ref())
+            .map(|capt| {
+                let hours = parse_match(capt.name("hours"));
+                let minutes = parse_match(capt.name("minutes"));
+                let seconds = parse_match(capt.name("seconds"));
+
+                let result = Duration::hours(hours as i64) +
+                    Duration::minutes(minutes as i64) +
+                    Duration::seconds(seconds as i64);
+
+                assert!(result >= Duration::zero());
+
+                result
+            })
+    }
+
+    let start_time = parse_captures(&START_REGEX, &s);
+    let dur = parse_captures(&DUR_REGEX, &s);
+    let end_time = parse_captures(&END_REGEX, s)
+        .or_else(|| start_time.and_then(|start| dur.map(|d| start + d)));
+
+    (start_time, end_time)
+}
+
+#[cfg(test)]
+mod test {
+    use super::*;
+    use time::Duration;
+
+    #[test]
+    fn test_start() {
+        let captures = START_REGEX.captures("start 1h2m3s").unwrap();
+
+        assert_eq!(captures.name("hours").unwrap().as_str(), "1");
+        assert_eq!(captures.name("minutes").unwrap().as_str(), "2");
+        assert_eq!(captures.name("seconds").unwrap().as_str(), "3");
+
+        assert!(START_REGEX.captures("").is_none());
+        assert!(START_REGEX.captures("start s").is_none());
+
+        let captures = START_REGEX.captures("start 1").unwrap();
+        assert_eq!(captures.name("seconds").unwrap().as_str(), "1");
+    }
+
+    #[test]
+    fn test_dur() {
+        let captures = DUR_REGEX.captures("dur 1h2m3s").unwrap();
+
+        assert_eq!(captures.name("hours").unwrap().as_str(), "1");
+        assert_eq!(captures.name("minutes").unwrap().as_str(), "2");
+        assert_eq!(captures.name("seconds").unwrap().as_str(), "3");
+
+        assert!(DUR_REGEX.captures("").is_none());
+        assert!(DUR_REGEX.captures("dur s").is_none());
+
+        let captures = DUR_REGEX.captures("dur 1").unwrap();
+        assert_eq!(captures.name("seconds").unwrap().as_str(), "1");
+    }
+
+    #[test]
+    fn test_end() {
+        let captures = END_REGEX.captures("end 1h2m3s").unwrap();
+
+        assert_eq!(captures.name("hours").unwrap().as_str(), "1");
+        assert_eq!(captures.name("minutes").unwrap().as_str(), "2");
+        assert_eq!(captures.name("seconds").unwrap().as_str(), "3");
+
+        assert!(END_REGEX.captures("").is_none());
+        assert!(END_REGEX.captures("end s").is_none());
+
+        let captures = END_REGEX.captures("end 1").unwrap();
+        assert_eq!(captures.name("seconds").unwrap().as_str(), "1");
+    }
+
+    #[test]
+    fn test_parse_matrix() {
+        fn format_time(d: &Duration) -> impl Iterator<Item=String> {
+            let seconds = d.num_seconds() % 60;
+            let minutes = d.num_minutes() % 60;
+            let hours = d.num_hours();
+
+            let elems = vec![true, false];
+
+            #[inline]
+            fn format_maybe_zero<S: AsRef<str>>(v: i64, unit: S, always: bool) -> String {
+                if always || v != 0 {
+                    format!("{}{}", v, unit.as_ref())
+                } else {
+                    "".to_owned()
+                }
+            }
+
+            iproduct!(elems.clone(), elems.clone(), elems)
+                .filter_map(move |(secs, mins, hr)| {
+                    if !secs && !mins && !hr {
+                        return None;
+                    }
+
+                    let hr_string = format_maybe_zero(hours, "h", hr);
+                    let mn_string = format_maybe_zero(minutes, "m", mins);
+                    let sec_string = format_maybe_zero(seconds, "s", secs);
+
+                    Some(format!("{}{}{}", hr_string, mn_string, sec_string))
+                })
+        }
+
+        #[inline]
+        fn produce_time_strings(d: Option<Duration>, names: Vec<&'static str>) -> Box<dyn Iterator<Item=String>> {
+            d
+                .map(move |dur| {
+                    let iter = iproduct!(format_time(&dur), names.into_iter())
+                        .map(|(time, name)| format!("{} {}", name, time));
+                    Box::new(iter) as Box<dyn Iterator<Item=String>>
+                })
+                .unwrap_or(Box::new(vec!["".to_owned()].into_iter()) as Box<dyn Iterator<Item=String>>)
+        }
+
+        #[inline]
+        fn dur_strs(v: Vec<Option<Duration>>, names: Vec<&'static str>) -> Vec<String> {
+            v
+                .into_iter()
+                .flat_map(|d| produce_time_strings(d, names.clone()))
+                .collect()
+        }
+
+        let start_times = vec![None, Some(Duration::seconds(0)), Some(Duration::seconds(32))];
+        let durs = vec![None, Some(Duration::seconds(0)), Some(Duration::seconds(123141))];
+        let end_times = vec![None, Some(Duration::seconds(0)), Some(Duration::seconds(19851598))];
+
+        let start_names = vec!["start", "begin", "beginning"];
+        let dur_names = vec!["dur", "duration"];
+        let end_names = vec!["end", "term", "terminate", "termination"];
+
+        let pairs = vec! [
+            (start_times, start_names),
+            (durs, dur_names),
+            (end_times, end_names),
+        ];
+
+        let elems = pairs.into_iter()
+            .map(|(times, names)| {
+                let result = times.into_iter()
+                    .flat_map(move |d| {
+                        let names_iter = names.clone().into_iter();
+
+                        d.as_ref().map(move |dur| {
+                            let dur = dur.clone();
+
+                            Box::new(iproduct!(format_time(&dur), names_iter)
+                                .map(move |(time, name)| Some((dur, format!("{} {}", name, time))))) as Box<dyn Iterator<Item=Option<(Duration, String)>>>
+                        }).unwrap_or_else(|| Box::new(::std::iter::once(None)))
+                    });
+
+                result.collect::<Vec<Option<(Duration, String)>>>()
+            })
+            .collect::<Vec<Vec<Option<(Duration, String)>>>>();
+
+        let start_iters = &elems[0];
+        let dur_iters = &elems[1];
+        let end_iters = &elems[2];
+
+        iproduct!(start_iters, dur_iters, end_iters)
+            .for_each(|(start, dur, end)| {
+                let s = vec![start, dur, end]
+                    .into_iter()
+                    .filter_map(|o| {
+                        o.as_ref().map(|(_, formatted)| formatted.to_owned())
+                    })
+                    .collect::<Vec<_>>()
+                    .join(" ");
+
+                println!("testing {}", s);
+
+                let (parse_start, parse_end) = parse_times(s);
+
+                match start {
+                    Some((dur, _)) => assert_eq!(*dur, parse_start.unwrap()),
+                    None => assert_eq!(None, parse_start),
+                }
+
+                match end {
+                    Some((d, _)) => assert_eq!(*d, parse_end.unwrap()),
+                    None => {
+                        match dur {
+                            Some((d, _)) => {
+                                match start {
+                                    Some((s, _)) => assert_eq!(parse_end.unwrap(), *s + *d),
+                                    None => assert_eq!(None, parse_end),
+                                }
+                            },
+                            None => assert_eq!(None, parse_end),
+                        }
+                    }
+                }
+            });
+    }
+}
+
 pub fn play(ctx: &mut Context, msg: &Message, mut args: Args) -> Result<()> {
     if args.len() == 0 {
         return _resume(ctx, msg);
diff --git a/src/commands/playback/types.rs b/src/commands/playback/types.rs
index 63479fd..380ee9d 100644
--- a/src/commands/playback/types.rs
+++ b/src/commands/playback/types.rs
@@ -5,12 +5,13 @@ use std::{
     time::Duration,
 };
 
+use chrono::Duration as CDuration;
 use either::{Either, Left, Right};
 use serenity::{
     client::bridge::voice::ClientVoiceManager,
     model::id::ChannelId,
     prelude::*,
-    voice::{LockedAudio, ytdl},
+    voice::{LockedAudio},
 };
 use typemap::Key;
 
@@ -41,6 +42,8 @@ pub struct PlayArgs {
     pub data: Either<String, Vec<u8>>,
     pub initiator: String,
     pub sender_channel: ChannelId,
+    pub start: Option<CDuration>,
+    pub end: Option<CDuration>,
 }
 
 #[derive(Clone)]
@@ -119,7 +122,7 @@ impl PlayQueue {
 
                 let src = match item.data {
                     Left(ref url) => {
-                        match ytdl(url) {
+                        match ytdl(url, item.start, item.end) {
                             Ok(src) => src,
                             Err(e) => {
                                 error!("bad link: {}; {:?}", url, e);
@@ -160,3 +163,117 @@ impl PlayQueue {
         });
     }
 }
+
+use std::{
+    io::{
+        Read,
+        Result as IoResult,
+        BufReader,
+    },
+    process::{
+        Command,
+        Stdio,
+        Child,
+    }
+};
+
+use serenity::{
+    voice::{
+        AudioSource,
+        pcm,
+    }
+};
+use serde_json::Value;
+use crate::Result;
+
+struct ChildContainer(Child);
+
+impl Read for ChildContainer {
+    fn read(&mut self, buffer: &mut [u8]) -> IoResult<usize> {
+        self.0.stdout.as_mut().unwrap().read(buffer)
+    }
+}
+
+impl Drop for ChildContainer {
+    fn drop (&mut self) {
+        if let Err(e) = self.0.kill() {
+            debug!("[Voice] Error awaiting child process: {:?}", e);
+        }
+    }
+}
+
+
+// Copied from serenity
+pub fn ytdl(uri: &str, start: Option<CDuration>, end: Option<CDuration>) -> Result<Box<AudioSource>> {
+    let args = [
+        "-f",
+        "webm[abr>0]/bestaudio/best",
+        "--no-playlist",
+        "--print-json",
+        "--skip-download",
+        uri,
+    ];
+
+    let out = Command::new("youtube-dl")
+        .args(&args)
+        .stdin(Stdio::null())
+        .output()?;
+
+    if !out.status.success() {
+        return Err(VoiceError::YouTubeDLRun(out).into());
+    }
+
+    let value = serde_json::from_reader(&out.stdout[..])?;
+    let mut obj = match value {
+        Value::Object(obj) => obj,
+        other => return Err(VoiceError::YouTubeDLProcessing(other).into()),
+    };
+
+    let uri = match obj.remove("url") {
+        Some(v) => match v {
+            Value::String(uri) => uri,
+            other => return Err(VoiceError::YouTubeDLUrl(other).into()),
+        },
+        None => return Err(VoiceError::YouTubeDLUrl(Value::Object(obj)).into()),
+    };
+
+    let start = start.unwrap_or(CDuration::zero());
+    let start_str = format!("{:02}:{:02}:{:02}", start.num_hours(), start.num_minutes() % 60, start.num_seconds() % 60);
+
+    let mut opts = vec! [
+        "-f",
+        "s16le",
+        "-ac",
+        "2", // force stereo -- this may cause issues
+        "-ar",
+        "48000",
+        "-acodec",
+        "pcm_s16le",
+        "-ss",
+        &start_str,
+    ]
+        .into_iter()
+        .map(|s| s.to_owned())
+        .collect::<Vec<_>>();
+
+    match end {
+        Some(e) => {
+            opts.push("-to".to_owned());
+            opts.push(format!("{:02}:{:02}:{:02}", e.num_hours(), e.num_minutes() % 60, e.num_seconds() % 60));
+        },
+        _ => {},
+    }
+
+    opts.push("-".to_owned());
+
+    let command = Command::new("ffmpeg")
+        .arg("-i")
+        .arg(uri)
+        .args(opts)
+        .stderr(Stdio::null())
+        .stdin(Stdio::null())
+        .stdout(Stdio::piped())
+        .spawn()?;
+
+    Ok(pcm(true, ChildContainer(command)))
+}