Identity: hashed stems under a tag, numbered volumes, scene tracks

From the top-100 groups:
- A hashed stem under text without a counter is the upload ("Seit 1753
  Tagen - usenet4ever.info - "055631a1_b6c820bc_…-u4e.part01.rar""): the
  day's uploads were one release of 3,747 files.
- A numbered volume as the extension, within the [i/M] total ("(????)
  [0659/2195] - "DN.VPL PCK.1508"", "TKY.ASN PCK.691."): keyed without it.
- Scene tracks under a bare counter ("[06/14] - "02-repiet_-_dont_think_
  twice_(extended_mix).mp3""): the artist's album bounded by the total.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

edge/src/names.rs

@@ -674,7 +674,9 @@ pub fn release_identity(poster: &str, subject: &str, name: &str) -> Release {
         let code = (1..=5).contains(&letters) && (2..=6).contains(&code_digits) && matches!(b.get(letters + code_digits), Some(b'-' | b'_' | b' '));
         index_at(0) || (code && index_at(letters + code_digits + 1))
     };
-    let tag = !image && !numbered && !test(&AUDIO, name) && describes(&stem) && !looks_random(&stem) && is_poster_tag(&remainder, &stem);
+    // A hashed stem under text without a counter is the upload, the text a tag ("Seit 1753 Tagen - usenet4ever.info - …").
+    let hashed = file_total.is_none() && test(&HASHED, &stem);
+    let tag = hashed || (!image && !numbered && !test(&AUDIO, name) && describes(&stem) && !looks_random(&stem) && is_poster_tag(&remainder, &stem));
     let prefix = if image { image_prefix(&stem) } else { String::new() };
     // An image set's subject may be one word, the model's name: /^[A-Za-z]{3,}$/.
     let one_word = image && remainder.len() >= 3 && remainder.bytes().all(|c| c.is_ascii_alphabetic());
@@ -697,14 +699,30 @@ pub fn release_identity(poster: &str, subject: &str, name: &str) -> Release {
     }
     // An audiobook's or album's tracks without a name around them: by their name without its numbers.
     if test(&AUDIO, name) {
+        // Scene tracks under a bare counter ("02-repiet_-_dont_think_twice_(extended_mix).mp3"): the artist's album.
+        if let Some(total) = post_total.filter(|&n| n != 0) {
+            if let Some(c) = SCENE_TRACK.captures(stem.as_bytes()) {
+                let artist = String::from_utf8(c[1].to_vec()).unwrap();
+                return Release { key: hash(&["stem", poster, &artist, &total.to_string()]), name: artist, source: "stem", file_total };
+            }
+        }
         let tracks = image_prefix(&stem);
         if !tracks.is_empty() {
             return Release { key: hash(&["stem", poster, &tracks]), name: tracks, source: "stem", file_total };
         }
     }
-    Release { key: hash(&["stem", poster, &stem]), name: stem, source: "stem", file_total }
+    // A numbered volume as the extension, within the counter's total ("DN.VPL PCK.1508" of 2195): one upload.
+    let base = match (VOLUME_NUMBER.captures(stem.as_bytes()), post_total.filter(|&n| n != 0)) {
+        (Some(c), Some(total)) if number(&c[2]) <= total as f64 => String::from_utf8(c[1].to_vec()).unwrap(),
+        _ => stem.clone(),
+    };
+    Release { key: hash(&["stem", poster, &base]), name: stem, source: "stem", file_total }
 }
 
+static HASHED: LazyLock<Regex> = LazyLock::new(|| re(r"(?i)^[0-9a-f]{8,}(?:_[0-9a-f]{6,}){2,}(?:-[0-9a-z]+)?$"));
+static SCENE_TRACK: LazyLock<Regex> = LazyLock::new(|| re(r"^[0-9]{1,3}[-_ .]+(.+?)(?:_-_| - |-)"));
+static VOLUME_NUMBER: LazyLock<Regex> = LazyLock::new(|| re(r"^(.*[^0-9. ])[. ]([0-9]{1,5})\.?$"));
+
 static GENERIC: LazyLock<Regex> = LazyLock::new(|| {
     re(r"(?i)^(video_ts|audio_ts|bdmv|certificate|hvdvd_ts|samples?|subs?|subtitles?|proof|cover|covers|extras?|featurettes?|(cd|dvd|disc|disk)[ ._-]?[0-9]{1,2})$")
 });
@@ -1254,6 +1272,22 @@ mod image_set_tests {
         assert_ne!(vlad("185", 77, "P8250001.JPG").key, vlad("234", 77, "P5300085.JPG").key);
     }
 
+    #[test]
+    fn hashed_stems_volume_numbers_and_scene_tracks() {
+        let u4e = |n: &str| release_identity("p", &format!(r#"Seit 1753 Tagen - usenet4ever.info - "{n}" yEnc"#), n);
+        assert_eq!(u4e("055631a1_b6c820bc_a856086c_85112a5-u4e.part01.rar").key, u4e("055631a1_b6c820bc_a856086c_85112a5-u4e.par2").key);
+        assert_ne!(u4e("055631a1_b6c820bc_a856086c_85112a5-u4e.part01.rar").key, u4e("4cc7c4c6_d3c2fecf_0bff51d6_d10df86-u4e.part01.rar").key);
+        let pck = |i: &str, n: &str| release_identity("p", &format!(r#"(????) [{i}/2195] - "{n}" yEnc"#), n);
+        assert_eq!(pck("0659", "DN.VPL PCK.1508").key, pck("0660", "DN.VPL PCK.1509").key);
+        assert_eq!(pck("0659", "DN.VPL PCK.1508").name, "DN.VPL PCK.1508");
+        let movie = |i: &str, n: &str| release_identity("p", &format!(r#"[{i}/30] - "{n}" yEnc"#), n);
+        assert_ne!(movie("01", "Movie.2008").key, movie("02", "Movie.2009").key);
+        let track = |i: &str, n: &str| release_identity("p", &format!(r#"[{i}/14] - "{n}" yEnc"#), n);
+        assert_eq!(track("06", "02-repiet_-_dont_think_twice_(extended_mix).mp3").key, track("07", "03-repiet_-_other_song.mp3").key);
+        assert_eq!(track("06", "02-repiet_-_dont_think_twice_(extended_mix).mp3").name, "repiet");
+        assert_eq!(track("01", "01-2bm_mq-real_rap_(intro).mp3").name, "2bm_mq");
+    }
+
     #[test]
     fn images_without_words_by_their_set() {
         let id = |n: &str, c: &str| release_identity("p", &format!(r#"##[ "{n}" ({c})"#), n);