Initial web

web/lib/sessions.ts

@@ -0,0 +1,38 @@
+import pool from '@/lib/db';
+import type { SessionBoundary } from '@/lib/types';
+
+/**
+ * Returns session-start timestamps where any gap > 30 min exists
+ * in the global tick_timing timeline.
+ */
+export async function getSessionBoundaries(
+  from: Date,
+  to: Date,
+): Promise<SessionBoundary[]> {
+  const result = await pool.query<{ real_time: Date; game_tick: string }>(
+    `SELECT real_time, game_tick
+     FROM tick_timing
+     WHERE real_time BETWEEN $1 AND $2
+     ORDER BY real_time ASC`,
+    [from, to],
+  );
+
+  const rows = result.rows;
+  if (rows.length === 0) return [];
+
+  const boundaries: SessionBoundary[] = [{
+    real_time: rows[0].real_time.toISOString(),
+    game_tick: parseInt(rows[0].game_tick, 10),
+  }];
+
+  for (let i = 1; i < rows.length; i++) {
+    if (rows[i].real_time.getTime() - rows[i - 1].real_time.getTime() > 30 * 60 * 1000) {
+      boundaries.push({
+        real_time: rows[i].real_time.toISOString(),
+        game_tick: parseInt(rows[i].game_tick, 10),
+      });
+    }
+  }
+
+  return boundaries;
+}