1 files changed, 53 insertions, 0 deletions
diff --git a/src/lib/Media/Anime/Airing/classify.ts b/src/lib/Media/Anime/Airing/classify.ts
new file mode 100644
index 00000000..9b7487d2
--- /dev/null
+++ b/src/lib/Media/Anime/Airing/classify.ts
@@ -0,0 +1,53 @@
+import type { Media } from '$lib/Data/AniList/media';
+
+export interface AnimeEpisodeState {
+  progress: number;
+  nextEpisode: number;
+  airedEpisodes: number;
+}
+
+const hasAired = (airingAt: number | undefined, nowEpochSeconds: number) =>
+  typeof airingAt === 'number' && airingAt <= nowEpochSeconds;
+
+export const getAnimeEpisodeState = (
+  media: Media,
+  nowEpochSeconds = Date.now() / 1000
+): AnimeEpisodeState => {
+  const progress = media.mediaListEntry?.progress || 0;
+  const nextEpisode =
+    media.nextAiringEpisode?.nativeEpisode || media.nextAiringEpisode?.episode || 0;
+
+  if (nextEpisode <= 0) {
+    return {
+      progress,
+      nextEpisode,
+      airedEpisodes: 0
+    };
+  }
+
+  let airedEpisodes = Math.max(0, nextEpisode - 1);
+  const airingAt = media.nextAiringEpisode?.airingAt;
+  const nativeAiringAt = media.nextAiringEpisode?.nativeAiringAt;
+
+  // If either source says the "next" episode already aired, treat it as released.
+  if (hasAired(airingAt, nowEpochSeconds) || hasAired(nativeAiringAt, nowEpochSeconds))
+    airedEpisodes = Math.max(airedEpisodes, nextEpisode);
+
+  return {
+    progress,
+    nextEpisode,
+    airedEpisodes
+  };
+};
+
+export const hasDueEpisodes = (media: Media, nowEpochSeconds = Date.now() / 1000) => {
+  const episodeState = getAnimeEpisodeState(media, nowEpochSeconds);
+
+  return episodeState.airedEpisodes > episodeState.progress;
+};
+
+export const hasNoAiredEpisodes = (media: Media, nowEpochSeconds = Date.now() / 1000) => {
+  const episodeState = getAnimeEpisodeState(media, nowEpochSeconds);
+
+  return episodeState.airedEpisodes <= 0;
+};