Disable gapless playback via runtime flag (#444)

* Enable gapless playback via runtime flag

* Set gapless playback as default, use `--disable-gapless` to turn it off

* Ensure sink restarts b/w tracks when gapless is disabled

playback/src/config.rs

@@ -30,6 +30,7 @@ pub struct PlayerConfig {
     pub bitrate: Bitrate,
     pub normalisation: bool,
     pub normalisation_pregain: f32,
+    pub gapless: bool,
 }
 
 impl Default for PlayerConfig {
@@ -38,6 +39,7 @@ impl Default for PlayerConfig {
             bitrate: Bitrate::default(),
             normalisation: false,
             normalisation_pregain: 0.0,
+            gapless: true,
         }
     }
 }

playback/src/player.rs

@@ -1065,6 +1065,9 @@ impl PlayerInternal {
         play: bool,
         position_ms: u32,
     ) {
+        if !self.config.gapless {
+            self.ensure_sink_stopped();
+        }
         // emit the correct player event
         match self.state {
             PlayerState::Playing {

src/main.rs

@@ -180,6 +180,11 @@ fn setup(args: &[String]) -> Setup {
             "",
             "autoplay",
             "autoplay similar songs when your music ends.",
+        )
+        .optflag(
+            "",
+            "disable-gapless",
+            "disable gapless playback.",
         );
 
     let matches = match opts.parse(&args[1..]) {
@@ -312,9 +317,9 @@ fn setup(args: &[String]) -> Setup {
             .as_ref()
             .map(|bitrate| Bitrate::from_str(bitrate).expect("Invalid bitrate"))
             .unwrap_or(Bitrate::default());
-
         PlayerConfig {
             bitrate: bitrate,
+            gapless: !matches.opt_present("disable-gapless"),
             normalisation: matches.opt_present("enable-volume-normalisation"),
             normalisation_pregain: matches
                 .opt_str("normalisation-pregain")