From 46fe19f1c0814fa3975f60dcdd17c1680b161c3c Mon Sep 17 00:00:00 2001
From: metamuffin <metamuffin@disroot.org>
Date: Mon, 29 Jan 2024 20:20:42 +0100
Subject: caching subtitles

---
 base/src/cache.rs           |  4 ++--
 common/src/jhls.rs          |  3 ++-
 stream/src/webvtt.rs        | 32 +++++++++++++++++++++++++-------
 transcoder/src/subtitles.rs |  4 ++--
 4 files changed, 31 insertions(+), 12 deletions(-)

diff --git a/base/src/cache.rs b/base/src/cache.rs
index 5e47d0e..68f191e 100644
--- a/base/src/cache.rs
+++ b/base/src/cache.rs
@@ -176,10 +176,10 @@ where
 
 pub async fn async_cache_memory<Fun, Fut, T>(
     seed: &[&str],
-    mut generate: Fun,
+    generate: Fun,
 ) -> Result<Arc<T>, anyhow::Error>
 where
-    Fun: FnMut() -> Fut,
+    Fun: FnOnce() -> Fut,
     Fut: Future<Output = Result<T, anyhow::Error>>,
     T: Encode + Decode + Send + Sync + 'static,
 {
diff --git a/common/src/jhls.rs b/common/src/jhls.rs
index f4448b6..12fa2d6 100644
--- a/common/src/jhls.rs
+++ b/common/src/jhls.rs
@@ -1,3 +1,4 @@
+use bincode::{Decode, Encode};
 /*
     This file is part of jellything (https://codeberg.org/metamuffin/jellything)
     which is licensed under the GNU Affero General Public License (version 3); see /COPYING.
@@ -32,7 +33,7 @@ pub enum EncodingProfile {
     },
 }
 
-#[derive(Debug, Serialize, Deserialize)]
+#[derive(Debug, Serialize, Deserialize, Encode, Decode)]
 pub struct SubtitleCue {
     pub start: f64,
     pub end: f64,
diff --git a/stream/src/webvtt.rs b/stream/src/webvtt.rs
index e9d03bf..b29c7c5 100644
--- a/stream/src/webvtt.rs
+++ b/stream/src/webvtt.rs
@@ -4,7 +4,7 @@
     Copyright (C) 2024 metamuffin <metamuffin.org>
 */
 use anyhow::{anyhow, Context, Result};
-use jellybase::CONF;
+use jellybase::{cache::async_cache_memory, CONF};
 use jellycommon::{stream::StreamSpec, LocalTrack, Node};
 use jellyremuxer::extract::extract_track;
 use jellytranscoder::subtitles::{parse_subtitles, write_webvtt};
@@ -26,16 +26,34 @@ pub async fn vtt_stream(
     let track = &node.public.media.unwrap().tracks[tracki];
     let cp = local_track.codec_private.clone();
 
-    let blocks =
-        tokio::task::spawn_blocking(move || extract_track(CONF.media_path.clone(), local_track))
+    let subtitles = async_cache_memory(
+        &[
+            "vtt",
+            &format!(
+                "{} {}",
+                local_track.path.to_str().unwrap(),
+                local_track.track
+            ),
+        ],
+        move || async move {
+            let blocks = tokio::task::spawn_blocking(move || {
+                extract_track(CONF.media_path.clone(), local_track)
+            })
             .await??;
+            let subtitles = parse_subtitles(&track.codec, cp, blocks)?;
+            Ok(subtitles)
+        },
+    )
+    .await?;
 
-    let subtitles = parse_subtitles(&track.codec, cp, blocks)?;
     let output = if json {
-        serde_json::to_string(&subtitles)?
+        serde_json::to_string(subtitles.as_ref())?
     } else {
-        write_webvtt(node.public.title.clone().unwrap_or_default(), subtitles)
-            .context("writing webvtt")?
+        write_webvtt(
+            node.public.title.clone().unwrap_or_default(),
+            subtitles.as_ref(),
+        )
+        .context("writing webvtt")?
     };
     tokio::task::spawn(async move {
         let _ = b.write_all(output.as_bytes()).await;
diff --git a/transcoder/src/subtitles.rs b/transcoder/src/subtitles.rs
index 9118ebc..2532781 100644
--- a/transcoder/src/subtitles.rs
+++ b/transcoder/src/subtitles.rs
@@ -28,7 +28,7 @@ pub fn parse_subtitles(
     .context(anyhow!("parsing {codec} subtitles"))
 }
 
-pub fn write_webvtt(title: String, subtitles: Vec<SubtitleCue>) -> anyhow::Result<String> {
+pub fn write_webvtt(title: String, subtitles: &[SubtitleCue]) -> anyhow::Result<String> {
     let mut out = String::new();
 
     writeln!(out, "WEBVTT - {title}")?; // TODO ensure title does not contain "-->"
@@ -39,7 +39,7 @@ pub fn write_webvtt(title: String, subtitles: Vec<SubtitleCue>) -> anyhow::Resul
         content,
     } in subtitles
     {
-        writeln!(out, "{} --> {}", format_time(start), format_time(end))?;
+        writeln!(out, "{} --> {}", format_time(*start), format_time(*end))?;
         writeln!(out, "- {content}")?;
         writeln!(out)?;
     }
-- 
cgit v1.2.3-70-g09d2