From 2b55c5b0af6b1c17334dcf27c0d967cdcc6ad894 Mon Sep 17 00:00:00 2001
From: Aaron Manning <contact@aaronmanning.net>
Date: Mon, 1 Sep 2025 09:42:15 +1000
Subject: [PATCH] separate playlist generation

---
 src/download.rs |  8 +++++
 src/input.rs    | 10 +++++--
 src/main.rs     | 14 +++++++--
 src/tagging.rs  | 78 ++++++++++++++++++++++++++++++++++++++++++++-----
 4 files changed, 98 insertions(+), 12 deletions(-)

diff --git a/src/download.rs b/src/download.rs
index 10dd1af..b096316 100644
--- a/src/download.rs
+++ b/src/download.rs
@@ -53,6 +53,14 @@ impl<'a> Specification<'a> {
     pub(crate) fn path_from_id(&self, id: &str) -> Option<&path::Path> {
         self.files.get(id).map(|v| &**v)
     }
+
+    pub(crate) fn feed(&self) -> &BTreeMap<chrono::NaiveDateTime, Vec<Episode<'a>>> {
+        &self.feed
+    }
+
+    pub(crate) fn into_feed_and_files(self) -> (BTreeMap<chrono::NaiveDateTime, Vec<Episode<'a>>>, HashMap<Cow<'a, str>, Cow<'a, path::Path>>) {
+        (self.feed, self.files)
+    }
 }
 
 #[derive(Debug, serde::Serialize, serde::Deserialize)]
diff --git a/src/input.rs b/src/input.rs
index 3ffbb6b..04663d8 100644
--- a/src/input.rs
+++ b/src/input.rs
@@ -42,9 +42,15 @@ pub(crate) enum Command {
         #[arg(long, short)]
         podcast: String,
     },
-    /// Tags files and generates playlists ready for use with an iPod.
+    /// Tags files for use with an iPod, such that they don't show up in albums and artists.
     Tag {
-        /// The podcast to tag and generate playlists for.
+        /// The podcast to tag.
+        #[arg(long, short)]
+        podcast: Option<String>,
+    },
+    /// Generates playlist for use with an iPod.
+    Playlist {
+        /// The podcast to generate the playlist for.
         #[arg(long, short)]
         podcast: Option<String>,
     },
diff --git a/src/main.rs b/src/main.rs
index 7d72d11..287b7ce 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -77,17 +77,25 @@ fn main() -> anyhow::Result<()> {
 
             spec.write_to(&spec_file)?;
         },
+        Command::Playlist { podcast } => {
+            if let Some(alias) = podcast {
+                tagging::generate_podcast_m3u(alias.as_str(), root)?;
+            } else {
+                for (alias, _) in &config.podcasts {
+                    tagging::generate_podcast_m3u(alias.as_str(), root)?;
+                }
+                tagging::generate_master_m3u(&config, root)?;
+            }
+        },
         Command::Tag { podcast } => {
             if let Some(alias) = podcast {
-                tagging::generate_m3u(alias.as_str(), root)?;
                 tagging::strip_tags(alias.as_str(), root)?;
             } else {
                 for (alias, _) in config.podcasts {
-                    tagging::generate_m3u(alias.as_str(), root)?;
                     tagging::strip_tags(alias.as_str(), root)?;
                 }
             }
-        }
+        },
     };
 
     Ok(())
diff --git a/src/tagging.rs b/src/tagging.rs
index 38f0ccc..ecdfc6f 100644
--- a/src/tagging.rs
+++ b/src/tagging.rs
@@ -1,12 +1,71 @@
-use std::{fs, path};
+use std::{fs, path, collections::BTreeMap};
 
-use crate::{folders, download};
+use crate::{input, folders, download};
 
 use anyhow::Context;
 
 use sanitise_file_name::sanitise;
 
-pub(crate) fn generate_m3u(
+pub(crate) fn generate_master_m3u(
+    config: &input::Config,
+    root: &path::Path,
+) -> anyhow::Result<()> {
+    let mut all_episodes = BTreeMap::<chrono::NaiveDateTime, Vec<_>>::new();
+
+    for (podcast, _) in &config.podcasts {
+        let output = folders::podcast_folder(root, podcast.as_str());
+        let spec_file = output.join("spec.toml");
+        let spec = download::Specification::read_from(&spec_file)?;
+
+        let (feed, files) = spec.into_feed_and_files();
+
+        for (published, episodes) in feed {
+            for episode in episodes {
+                let path = output.join(
+                    files.get(episode.id()).unwrap()
+                );
+                let entry = m3u::path_entry({
+                    let relative = path.strip_prefix(
+                        output.parent().unwrap()
+                    ).unwrap();
+                    path::Path::new("/Podcasts").join(relative)
+                });
+                
+                match all_episodes.get_mut(&published) {
+                    Some(existing) => {
+                        existing.push(entry)
+                    },
+                    None => {
+                        all_episodes.insert(
+                            published,
+                            vec![entry]
+                        );
+                    }
+                }
+            }
+        }
+    }
+
+    let playlists_folder = root.join("Playlists");
+    if !playlists_folder.exists() {
+        fs::create_dir(&playlists_folder)
+            .context(format!("failed to create output directory for playlists"))?;
+    }
+    let mut path = playlists_folder.join("_master");
+    path.set_extension("m3u");
+
+    let mut file = fs::File::create(path)?;
+
+    let mut writer = m3u::Writer::new(&mut file);
+    for entry in all_episodes.values().map(|entries| entries.iter()).flatten() {
+        writer.write_entry(entry)?;
+    }
+
+    Ok(())
+}
+
+
+pub(crate) fn generate_podcast_m3u(
     alias: &str,
     root: &path::Path,
 ) -> anyhow::Result<()> {
@@ -54,6 +113,8 @@ pub(crate) fn strip_tags(
     alias: &str,
     root: &path::Path,
 ) -> anyhow::Result<()> {
+    println!("[info] retagging podcast {}", alias);
+    
     let output = folders::podcast_folder(root, alias);
     let spec_file = output.join("spec.toml");
 
@@ -63,13 +124,16 @@ pub(crate) fn strip_tags(
         let path = output.join(
             spec.path_from_id(episode.id()).unwrap()
         );
-        let mut file = audiotags::Tag::new().read_from_path(
+        let file = audiotags::Tag::new().read_from_path(
             &path
-        )?;
+        );
+
+        let Ok(mut file) = file else {
+            println!("[warning] failed to read mp3 audio tags file. skipping.");
+            continue
+        };
 
-        file.remove_title();
         file.remove_artist();
-        file.remove_year();
         file.remove_album();
         file.set_genre("Podcast");
         file.set_title(episode.title());