add option for compression

src/file_sink.rs

@@ -1,24 +1,33 @@
 use std::path::Path;
 
 use audiotags::{Tag, TagType};
-use librespot::{playback::{audio_backend::{Open, Sink, SinkError}, config::AudioFormat, decoder::AudioPacket, convert::Converter}};
+use librespot::playback::{
+    audio_backend::{Open, Sink, SinkError},
+    config::AudioFormat,
+    convert::Converter,
+    decoder::AudioPacket,
+};
 
 // extern crate flac_bound;
 
-use flac_bound::{FlacEncoder};
+use flac_bound::FlacEncoder;
 
 use crate::TrackMetadata;
 
 pub struct FileSink {
     sink: String,
     content: Vec<i32>,
-    metadata: Option<TrackMetadata>
+    metadata: Option<TrackMetadata>,
+    compression: u32,
 }
 
 impl FileSink {
     pub fn add_metadata(&mut self, meta: TrackMetadata) {
         self.metadata = Some(meta);
     }
+    pub fn set_compression(&mut self, compression: u32) {
+        self.compression = compression;
+    }
 }
 
 impl Open for FileSink {
@@ -28,7 +37,8 @@ impl Open for FileSink {
             FileSink {
                 sink: file,
                 content: Vec::new(),
-                metadata: None
+                metadata: None,
+                compression: 4,
             }
         } else {
             panic!();
@@ -42,21 +52,33 @@ impl Sink for FileSink {
     }
 
     fn stop(&mut self) -> Result<(), SinkError> {
-        let mut encoder = FlacEncoder::new().unwrap().channels(2).bits_per_sample(16).compression_level(4).init_file(&self.sink).unwrap();
-        encoder.process_interleaved(self.content.as_slice(), (self.content.len()/2) as u32).unwrap();
+        let mut encoder = FlacEncoder::new()
+            .unwrap()
+            .channels(2)
+            .bits_per_sample(16)
+            .compression_level(*&self.compression)
+            .init_file(&self.sink)
+            .unwrap();
+        encoder
+            .process_interleaved(self.content.as_slice(), (self.content.len() / 2) as u32)
+            .unwrap();
         encoder.finish().unwrap();
 
         match &self.metadata {
             Some(meta) => {
-                let mut tag = Tag::new().with_tag_type(TagType::Flac).read_from_path(Path::new(&self.sink)).unwrap();
+                let mut tag = Tag::new()
+                    .with_tag_type(TagType::Flac)
+                    .read_from_path(Path::new(&self.sink))
+                    .unwrap();
 
                 tag.set_album_title(&meta.album);
                 for artist in &meta.artists {
                     tag.add_artist(artist);
                 }
                 tag.set_title(&meta.track_name);
-                tag.write_to_path(&self.sink).expect("Failed to write metadata");
-            },
+                tag.write_to_path(&self.sink)
+                    .expect("Failed to write metadata");
+            }
             None => (),
         }
         Ok(())

src/main.rs

@@ -45,6 +45,13 @@ struct Opt {
         help = "Prefixing the filename with its index in the playlist"
     )]
     ordered: bool,
+    #[structopt(
+        short = "c",
+        long = "compression",
+        help = "Setting the flac compression level from 0 (fastest, least compression) to
+8 (slowest, most compression). A value larger than 8 will be reated as 8. Defaults to 4."
+    )]
+    compression: Option<u32>,
 }
 
 #[derive(Clone)]
@@ -67,6 +74,7 @@ async fn download_tracks(
     destination: PathBuf,
     tracks: Vec<SpotifyId>,
     ordered: bool,
+    compression: Option<u32>,
 ) {
     let player_config = PlayerConfig::default();
     let bar_style = ProgressStyle::default_bar()
@@ -116,6 +124,9 @@ async fn download_tracks(
             librespot::playback::config::AudioFormat::S16,
         );
         file_sink.add_metadata(metadata);
+        if let Some(compression) = compression {
+            file_sink.set_compression(compression);
+        }
         let (mut player, _) =
             Player::new(player_config.clone(), session.clone(), None, move || {
                 Box::new(file_sink)
@@ -184,6 +195,7 @@ async fn main() {
         PathBuf::from(opt.destination),
         tracks,
         opt.ordered,
+        opt.compression,
     )
     .await;
 }