From b6a696a08de320602373f9796689570ca4b936da Mon Sep 17 00:00:00 2001
From: Toni Barth <software@satoprogs.de>
Date: Tue, 5 Mar 2024 12:38:16 +0100
Subject: [PATCH] add hit post-processing via ffmpeg to convert to mp3 and cut
 off the beginning according to the offset

---
 Dockerfile         |  2 +-
 server/Cargo.toml  |  1 +
 server/src/hits.rs | 35 +++++++++++++++++++++++++++++++++--
 3 files changed, 35 insertions(+), 3 deletions(-)

diff --git a/Dockerfile b/Dockerfile
index a72474d..4dc4a84 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -28,7 +28,7 @@ FROM debian:bookworm-slim
 # prepare the OS
 
 RUN DEBIAN_FRONTEND=noninteractive apt-get update && \
-    apt-get -y install --no-install-recommends libssl-dev ca-certificates && \
+    apt-get -y install --no-install-recommends libssl-dev ca-certificates ffmpeg && \
     apt-get clean && \
     rm -rf /var/lib/apt/lists/*
 
diff --git a/server/Cargo.toml b/server/Cargo.toml
index 4c670dd..55aabf2 100644
--- a/server/Cargo.toml
+++ b/server/Cargo.toml
@@ -7,6 +7,7 @@ edition = "2021"
 
 [dependencies]
 dotenvy = "0.15.7"
+ffmpeg-cli = "0.1.0"
 hex = "0.4.3"
 names = "0.14.0"
 regex = "1.10.3"
diff --git a/server/src/hits.rs b/server/src/hits.rs
index a52bb09..02f4497 100644
--- a/server/src/hits.rs
+++ b/server/src/hits.rs
@@ -1,10 +1,16 @@
+use ffmpeg_cli::{FfmpegBuilder, File, Parameter};
 use regex::Regex;
 use rocket::{
     fairing::{Fairing, Info, Kind},
     Orbit, Rocket,
 };
 use rusty_ytdl::{Video, VideoOptions, VideoQuality, VideoSearchOptions};
-use std::{env, fs::create_dir_all, path::Path};
+use std::{
+    env,
+    fs::{create_dir_all, remove_file},
+    path::Path,
+    process::Stdio,
+};
 
 include!(concat!(env!("OUT_DIR"), "/hits.rs"));
 
@@ -63,9 +69,34 @@ impl Fairing for HitsterDownloader {
                     );
 
                     video
-                        .download(format!("{}/{}.mp4", download_dir.as_str(), id))
+                        .download(format!("{}/{}.opus", download_dir.as_str(), id))
                         .await
                         .unwrap();
+
+                    println!("Post-processing opus to mp3...");
+
+                    let in_file = format!("{}/{}.opus", download_dir.as_str(), id);
+                    let out_file = format!("{}/{}.mp3", download_dir.as_str(), id);
+                    let offset = format!("{}", hit.playback_offset);
+
+                    let builder = FfmpegBuilder::new()
+                        .stderr(Stdio::piped())
+                        .option(Parameter::Single("nostdin"))
+                        .option(Parameter::Single("y"))
+                        .input(File::new(in_file.as_str()))
+                        .output(
+                            File::new(out_file.as_str())
+                                .option(Parameter::KeyValue("ss", offset.as_str()))
+                                .option(Parameter::Single("vn"))
+                                .option(Parameter::Single("sn"))
+                                .option(Parameter::Single("dn")),
+                        );
+
+                    let ffmpeg = builder.run().await.unwrap();
+
+                    ffmpeg.process.wait_with_output().unwrap();
+
+                    remove_file(in_file.as_str()).unwrap();
                 }
             }
         }