refactor: stricter domain: chat

toju-app/src/app/domains/chat/domain/rules/message-sync.rules.ts

@@ -0,0 +1,59 @@
+/** Maximum number of recent messages to include in sync inventories. */
+export const INVENTORY_LIMIT = 1000;
+
+/** Number of messages per chunk for inventory / batch transfers. */
+export const CHUNK_SIZE = 200;
+
+/** Aggressive sync poll interval (10 seconds). */
+export const SYNC_POLL_FAST_MS = 10_000;
+
+/** Idle sync poll interval after a clean (no-new-messages) cycle (15 minutes). */
+export const SYNC_POLL_SLOW_MS = 900_000;
+
+/** Sync timeout duration before auto-completing a cycle (5 seconds). */
+export const SYNC_TIMEOUT_MS = 5_000;
+
+/** Large limit used for legacy full-sync operations. */
+export const FULL_SYNC_LIMIT = 10_000;
+
+/** Inventory item representing a message's sync state. */
+export interface InventoryItem {
+  id: string;
+  ts: number;
+  rc: number;
+  ac?: number;
+}
+
+/** Splits an array into chunks of the given size. */
+export function chunkArray<T>(items: T[], size: number): T[][] {
+  const chunks: T[][] = [];
+
+  for (let index = 0; index < items.length; index += size) {
+    chunks.push(items.slice(index, index + size));
+  }
+
+  return chunks;
+}
+
+/** Identifies missing or stale message IDs by comparing remote items against a local map. */
+export function findMissingIds(
+  remoteItems: readonly { id: string; ts: number; rc?: number; ac?: number }[],
+  localMap: ReadonlyMap<string, { ts: number; rc: number; ac: number }>
+): string[] {
+  const missing: string[] = [];
+
+  for (const item of remoteItems) {
+    const local = localMap.get(item.id);
+
+    if (
+      !local ||
+      item.ts > local.ts ||
+      (item.rc !== undefined && item.rc !== local.rc) ||
+      (item.ac !== undefined && item.ac !== local.ac)
+    ) {
+      missing.push(item.id);
+    }
+  }
+
+  return missing;
+}