feat(api): sync catalog with problems moved to review issues

apps/api/src/catalog.ts

@@ -9,9 +9,16 @@
  * issue title — the title carries only the LC number and the problem's name,
  * so relabelling a problem is enough to move it and titles stay readable.
  * The `problem` label is what marks a sub-issue as curriculum.
+ *
+ * A topic's problems are its sub-issues PLUS those re-parented into a
+ * `Review <N> — <Phase>` issue (reviews.ts recovers which topic each came
+ * from). Walking topic sub-issues alone would silently freeze a moved
+ * problem's row: upserts only, so nothing breaks — its labels just stop
+ * syncing.
  */
 import { DIFFICULTIES, SETS, workingDay } from "./srs.ts";
 import type { GitHub } from "./github.ts";
+import { movedFromTopics, readReviews } from "./reviews.ts";
 
 const TITLE_RE = /^LC (\d+) · (.+)$/;
 
@@ -72,24 +79,29 @@ export async function reconcileCatalog(db: D1Database, gh: GitHub): Promise<Reco
     );
   }
 
+  const moved = movedFromTopics(await readReviews(gh));
   let problems = 0;
   let deferredSeen = 0;
   for (const t of topics) {
+    const members: { number: number; title: string; labels: string[] }[] = [];
     for await (const raw of gh.list(`/repos/${gh.repo}/issues/${t.number}/sub_issues`)) {
       if (!raw || typeof raw !== "object") continue;
       if (!("number" in raw) || typeof raw.number !== "number") continue;
       if (!("title" in raw) || typeof raw.title !== "string") continue;
-      const labels = labelNames(raw);
+      members.push({ number: raw.number, title: raw.title, labels: labelNames(raw) });
+    }
+    members.push(...(moved.get(t.number) ?? []));
+    for (const { number, title, labels } of members) {
       if (!labels.includes("problem")) continue; // non-curriculum sub-issue
-      const m = raw.title.match(TITLE_RE);
+      const m = title.match(TITLE_RE);
       if (!m) {
-        console.warn(`catalog: #${raw.number} is a problem but not titled "LC <n> · <name>"`);
+        console.warn(`catalog: #${number} is a problem but not titled "LC <n> · <name>"`);
         continue;
       }
       const difficulty = DIFFICULTIES.find((d) => labels.includes(`diff:${d}`));
       const set = SETS.find((s) => labels.includes(`set:${s}`));
       if (!difficulty || !set) {
-        console.warn(`catalog: #${raw.number} is missing a diff:/set: label — skipped`);
+        console.warn(`catalog: #${number} is missing a diff:/set: label — skipped`);
         continue;
       }
       const lc = Number(m[1]);
@@ -106,7 +118,7 @@ export async function reconcileCatalog(db: D1Database, gh: GitHub): Promise<Reco
              ON CONFLICT(lc_number) DO UPDATE SET
                issue = ?2, topic_issue = ?3, title = ?4, difficulty = ?5, set_label = ?6`,
           )
-          .bind(lc, raw.number, t.number, m[2]!, difficulty, set, defer),
+          .bind(lc, number, t.number, m[2]!, difficulty, set, defer),
       );
       problems++;
     }

apps/api/src/reviews.ts

@@ -0,0 +1,136 @@
+/**
+ * `Review <N> — <Phase>` issues: the transfer phase's day blocks. Problems were
+ * re-parented into them from their topics (`replace_parent` — a GitHub issue
+ * has exactly one parent), so a topic's sub-issue list no longer names every
+ * problem it owns. This module is the ONE recovery of that ownership: each
+ * moved problem's topic is its last `parent_issue_removed` event naming a
+ * topic, which GitHub records and no human edits.
+ *
+ * Two consumers must agree on it: the Worker's catalog reconcile
+ * (catalog.ts — else a moved problem's D1 row stops syncing its labels) and
+ * the CLI's topic rules (apps/cli/topics.ts — else close-topics and the
+ * release bodies change when a problem moves). Hence it lives here, the lower
+ * layer, the way apps/cli already imports srs.ts.
+ *
+ * Library: side-effect-free on import; the caller passes its GitHub client —
+ * the Worker's or the CLI's, which share the three members used here.
+ */
+import type { GitHub } from "./github.ts";
+
+/** `Review 7 — Nodal & Grid`, never the Worker's weekly `Review — Week N` gate. */
+const REVIEW_TITLE = /^Review \d+ — /;
+const TOPIC_TITLE = /^Topic \d+ — /;
+
+/** One problem issue as a topic or review lists it. */
+export interface Problem {
+  number: number;
+  /** `LC <num> · <Name>`. */
+  title: string;
+  /** ISO instant the issue closed; null while it is open. */
+  closedAt: string | null;
+  labels: string[];
+}
+
+export interface Review {
+  number: number;
+  title: string;
+  open: boolean;
+  /** Sub-issues in the order GitHub lists them (the solve order). */
+  problems: (Problem & { fromTopic: number | null })[];
+}
+
+/**
+ * Every `Review <N> — <Phase>` issue, open and closed, with its sub-issues.
+ * One GraphQL request per 50 `review`-labelled issues (the Worker's weekly
+ * gate issues share the label and are dropped by title): the sub-issues and
+ * the timeline filter ride along, so recovering each problem's source topic
+ * costs no extra request. That matters in the Worker, whose nightly cron
+ * spends its subrequest budget on the catalog walk and the digest.
+ */
+export async function readReviews(gh: Pick<GitHub, "repo" | "graphql">): Promise<Review[]> {
+  const [owner, name] = gh.repo.split("/");
+  const reviews: Review[] = [];
+  for (let after: string | null = null; ; ) {
+    // Shape fixed by the query below; GraphQL errors throw in gh.graphql().
+    const data = (await gh.graphql(
+      `query($owner: String!, $name: String!, $after: String) {
+        repository(owner: $owner, name: $name) {
+          issues(labels: ["review"], first: 50, after: $after, orderBy: { field: CREATED_AT, direction: ASC }) {
+            pageInfo { hasNextPage endCursor }
+            nodes {
+              number title state
+              subIssues(first: 50) {
+                pageInfo { hasNextPage }
+                nodes {
+                  number title state closedAt
+                  labels(first: 20) { nodes { name } }
+                  timelineItems(itemTypes: [PARENT_ISSUE_REMOVED_EVENT], last: 10) {
+                    nodes { ... on ParentIssueRemovedEvent { parent { number title } } }
+                  }
+                }
+              }
+            }
+          }
+        }
+      }`,
+      { owner, name, after },
+    )) as {
+      repository: {
+        issues: {
+          pageInfo: { hasNextPage: boolean; endCursor: string | null };
+          nodes: {
+            number: number;
+            title: string;
+            state: "OPEN" | "CLOSED";
+            subIssues: {
+              pageInfo: { hasNextPage: boolean };
+              nodes: {
+                number: number;
+                title: string;
+                state: "OPEN" | "CLOSED";
+                closedAt: string | null;
+                labels: { nodes: { name: string }[] };
+                timelineItems: { nodes: { parent: { number: number; title: string } | null }[] };
+              }[];
+            };
+          }[];
+        };
+      };
+    };
+    const page = data.repository.issues;
+    for (const issue of page.nodes) {
+      if (!REVIEW_TITLE.test(issue.title)) continue;
+      // A review is one day's handful; more than a page means a mis-linked issue.
+      if (issue.subIssues.pageInfo.hasNextPage) throw new Error(`review #${issue.number} has over 50 sub-issues`);
+      reviews.push({
+        number: issue.number,
+        title: issue.title,
+        open: issue.state === "OPEN",
+        problems: issue.subIssues.nodes.map((p) => ({
+          number: p.number,
+          title: p.title,
+          closedAt: p.state === "CLOSED" ? p.closedAt : null,
+          labels: p.labels.nodes.map((l) => l.name),
+          // Oldest first, so the last topic it left is its owner; a later
+          // review-to-review move names a review and is skipped.
+          fromTopic:
+            p.timelineItems.nodes.findLast((e) => e.parent && TOPIC_TITLE.test(e.parent.title))?.parent?.number ?? null,
+        })),
+      });
+    }
+    if (!page.pageInfo.hasNextPage) break;
+    after = page.pageInfo.endCursor;
+  }
+  return reviews.sort((a, b) => a.number - b.number);
+}
+
+/** Topic -> the problems moved out of it into Review issues, in review order. */
+export function movedFromTopics(reviews: Review[]): Map<number, Problem[]> {
+  const moved = new Map<number, Problem[]>();
+  for (const review of reviews) {
+    for (const { fromTopic, ...problem } of review.problems) {
+      if (fromTopic !== null) moved.set(fromTopic, [...(moved.get(fromTopic) ?? []), problem]);
+    }
+  }
+  return moved;
+}