feat: schedule next airing episode

happens when new title is saved, or when new episode internal route is run successfully

src/libs/anilist/getNextEpisodeAiringAt.ts

@@ -0,0 +1,28 @@
+import { graphql } from "gql.tada";
+import { GraphQLClient } from "graphql-request";
+
+const GetNextEpisodeAiringAtQuery = graphql(`
+  query GetNextEpisodeAiringAt($id: Int!) {
+    Media(id: $id) {
+      nextAiringEpisode {
+        episode
+        timeUntilAiring
+      }
+    }
+  }
+`);
+
+export function getNextEpisodeTimeUntilAiring(aniListId: number) {
+  const client = new GraphQLClient("https://graphql.anilist.co/");
+
+  return client
+    .request(GetNextEpisodeAiringAtQuery, { id: aniListId })
+    .then((data) => {
+      const nextAiring = data!.Media!.nextAiringEpisode;
+      if (!nextAiring) {
+        return null;
+      }
+
+      return nextAiring;
+    });
+}

src/libs/maybeScheduleNextAiringEpisode.ts

@@ -0,0 +1,32 @@
+import { Client } from "@upstash/qstash";
+import type { HonoRequest } from "hono";
+
+import { setTitleMessage } from "~/models/titleMessages";
+import type { Env } from "~/types/env";
+
+import { getNextEpisodeTimeUntilAiring } from "./anilist/getNextEpisodeAiringAt";
+import { getCurrentDomain } from "./getCurrentDomain";
+
+export async function maybeScheduleNextAiringEpisode(
+  env: Env,
+  req: HonoRequest,
+  aniListId: number,
+) {
+  const nextAiring = await getNextEpisodeTimeUntilAiring(aniListId);
+  if (!nextAiring) {
+    return;
+  }
+
+  const { timeUntilAiring, episode: nextEpisode } = nextAiring;
+  const client = new Client({ token: env.QSTASH_TOKEN });
+
+  const domain = getCurrentDomain(req);
+  const { messageId } = await client.publishJSON({
+    url: `${domain}/internal/new-episode`,
+    body: { aniListId, episode: nextEpisode },
+    retries: 0,
+    delay: timeUntilAiring,
+    contentBasedDeduplication: true,
+  });
+  await setTitleMessage(env, aniListId, messageId);
+}