Merge #182: name the season deck's real state

Closes #182
2026-08-24 21:27:42 +01:00
parent d474909ab5 1e03873209
commit 93c064701c
14 changed files with 782 additions and 45 deletions
@@ -10,7 +10,7 @@
 //! Re-grabbing a pack once an airing season completes is deliberately not
 //! done (§14): a season with any episode already on disk grabs per episode.

-use std::time::SystemTime;
+use std::time::{Duration, SystemTime};

 /// How a season's missing wanted episodes should be grabbed next.
 #[derive(Clone, Copy, Debug, Eq, PartialEq)]
@@ -37,24 +37,75 @@ pub struct SeasonGrabFacts<'a> {
    pub pack_backoff_active: bool,
 }

-/// Picks the grab mode for one season.
+/// Why a season is not on the season-pack lane.
+///
+/// The season release deck (§9.3) is empty for a season on the per-episode
+/// lane and stays empty however long it waits, so it has to name which of
+/// these it is rather than blaming a sweep that is not coming (#182).
+/// Ordered by how fundamental the answer is: an unaired episode outranks a
+/// failed pack, because clearing the failure would still not earn a pack.
+#[derive(Clone, Copy, Debug, Eq, PartialEq)]
+pub enum PerEpisodeReason {
+    /// No episodes are known for the season, so there is nothing to pack.
+    NoEpisodes,
+    /// An episode has not aired, or carries no air date at all.
+    StillAiring,
+    /// §14: a pack would re-import episodes that are already on disk.
+    EpisodesOnDisk,
+    /// §6.2: a failed pack grab's backoff window is still open.
+    PackBackoff,
+}
+
+/// Why one season takes the per-episode lane, or `None` when it takes the
+/// pack lane.
 ///
 /// A season is fully released only when every known episode has an air date
 /// in the past. An episode with no date could still be unaired, and grabbing
 /// a "complete" pack of a season that is not complete costs a whole torrent
 /// of the wrong thing — so an undated episode keeps the season per-episode.
 #[must_use]
-pub fn season_grab_mode(facts: &SeasonGrabFacts<'_>) -> SeasonGrabMode {
-    let fully_released = !facts.air_dates.is_empty()
-        && facts
-            .air_dates
-            .iter()
-            .all(|date| date.is_some_and(|date| date <= facts.now));
+pub fn season_grab_reason(facts: &SeasonGrabFacts<'_>) -> Option<PerEpisodeReason> {
+    if facts.air_dates.is_empty() {
+        return Some(PerEpisodeReason::NoEpisodes);
+    }
+    if !facts
+        .air_dates
+        .iter()
+        .all(|date| date.is_some_and(|date| date <= facts.now))
+    {
+        return Some(PerEpisodeReason::StillAiring);
+    }
+    if facts.any_episode_on_disk {
+        return Some(PerEpisodeReason::EpisodesOnDisk);
+    }
+    if facts.pack_backoff_active {
+        return Some(PerEpisodeReason::PackBackoff);
+    }
+    None
+}

-    if fully_released && !facts.any_episode_on_disk && !facts.pack_backoff_active {
-        SeasonGrabMode::SeasonPack
-    } else {
-        SeasonGrabMode::PerEpisode
+/// Picks the grab mode for one season.
+#[must_use]
+pub fn season_grab_mode(facts: &SeasonGrabFacts<'_>) -> SeasonGrabMode {
+    match season_grab_reason(facts) {
+        None => SeasonGrabMode::SeasonPack,
+        Some(_) => SeasonGrabMode::PerEpisode,
+    }
+}
+
+/// §6.2's targeted-search curve: `1h → 6h → 1d → 3d`, capped at 7d, indexed
+/// by how many attempts have already been spent.
+///
+/// The pack lane counts a season's failed pack grabs as its attempts, so the
+/// deck can say when the lane reopens rather than only that it is shut.
+#[must_use]
+pub fn search_backoff(attempts: i64) -> Duration {
+    match attempts {
+        ..=1 => Duration::from_hours(1),
+        2 => Duration::from_hours(6),
+        3 => Duration::from_hours(24),
+        4 => Duration::from_hours(72),
+        _ => Duration::from_hours(24 * 7),
    }
 }

@@ -122,4 +173,74 @@ mod tests {
        facts.any_episode_on_disk = true;
        assert_eq!(season_grab_mode(&facts), SeasonGrabMode::PerEpisode);
    }
+
+    /// #182: the deck says which of the four it is, not just "not a pack".
+    #[test]
+    fn the_reason_names_the_condition_that_holds_the_pack_lane_shut() {
+        assert_eq!(
+            season_grab_reason(&facts(&[])),
+            Some(PerEpisodeReason::NoEpisodes)
+        );
+
+        let airing = [
+            Some(SystemTime::UNIX_EPOCH + 10 * DAY),
+            Some(SystemTime::UNIX_EPOCH + 110 * DAY),
+        ];
+        assert_eq!(
+            season_grab_reason(&facts(&airing)),
+            Some(PerEpisodeReason::StillAiring)
+        );
+        let undated = [Some(SystemTime::UNIX_EPOCH + 10 * DAY), None];
+        assert_eq!(
+            season_grab_reason(&facts(&undated)),
+            Some(PerEpisodeReason::StillAiring)
+        );
+
+        let aired = [Some(SystemTime::UNIX_EPOCH + 10 * DAY)];
+        let mut on_disk = facts(&aired);
+        on_disk.any_episode_on_disk = true;
+        assert_eq!(
+            season_grab_reason(&on_disk),
+            Some(PerEpisodeReason::EpisodesOnDisk)
+        );
+
+        let mut backoff = facts(&aired);
+        backoff.pack_backoff_active = true;
+        assert_eq!(
+            season_grab_reason(&backoff),
+            Some(PerEpisodeReason::PackBackoff)
+        );
+
+        assert_eq!(season_grab_reason(&facts(&aired)), None);
+    }
+
+    /// A failed pack is not the headline when the season could not have had
+    /// a pack anyway — clearing it would change nothing.
+    #[test]
+    fn an_unaired_episode_outranks_a_failed_pack() {
+        let airing = [
+            Some(SystemTime::UNIX_EPOCH + 10 * DAY),
+            Some(SystemTime::UNIX_EPOCH + 110 * DAY),
+        ];
+        let mut facts = facts(&airing);
+        facts.pack_backoff_active = true;
+        facts.any_episode_on_disk = true;
+        assert_eq!(
+            season_grab_reason(&facts),
+            Some(PerEpisodeReason::StillAiring)
+        );
+    }
+
+    /// §6.2's curve, shared by the pack lane so the deck can say when it
+    /// reopens rather than only that it is shut.
+    #[test]
+    fn the_backoff_curve_climbs_and_caps_at_a_week() {
+        assert_eq!(search_backoff(0), Duration::from_hours(1));
+        assert_eq!(search_backoff(1), Duration::from_hours(1));
+        assert_eq!(search_backoff(2), Duration::from_hours(6));
+        assert_eq!(search_backoff(3), DAY);
+        assert_eq!(search_backoff(4), 3 * DAY);
+        assert_eq!(search_backoff(5), 7 * DAY);
+        assert_eq!(search_backoff(50), 7 * DAY);
+    }
 }
@@ -14,7 +14,10 @@ pub mod status;
 pub mod tracking;

 pub use arr_parse::NameClaims as ParsedRelease;
-pub use grabbing::{season_grab_mode, SeasonGrabFacts, SeasonGrabMode};
+pub use grabbing::{
+    search_backoff, season_grab_mode, season_grab_reason, PerEpisodeReason, SeasonGrabFacts,
+    SeasonGrabMode,
+};
 pub use matching::{
    match_episode, match_movie, EpisodeMatch, MatchKind, MatchShape, MovieMatch, ReleaseIds,
    WantedEpisode, WantedMovie,