perf(ai): kontiguitas batch budget + max_tokens dinamis + urutan kronologis RETURNING

- pickBatchWithinBudget: stop di overflow pertama (break), bukan skip — batch tetap prefix kronologis tanpa gap analisis di tengah timeline. Diekstrak ke batchBudget.ts (pure, estimator di-inject) + regression test. - callModerationLLM: param opsional maxTokens; text/media caller menghitung ceiling dari estimasi prompt (floor 2048, cap 16384) — batch kecil tak lagi reserve window completion 16k. - getPending/IncompleteMessagesByConversation: sort hasil UPDATE..RETURNING by created_at ASC — Postgres tak menjamin urutan, konsumen (anchor konteks messages[0], prefix batch) bergantung pada urutan kronologis.
2026-08-22 17:19:41 +07:00
parent 1397380fe9
commit 16becd5340
8 changed files with 230 additions and 19 deletions
@@ -0,0 +1,91 @@
+import { describe, expect, it } from "vitest";
+import {
+  pickBatchWithinBudget,
+  type TokenEstimator,
+} from "../src/modules/ai-moderation/batchBudget.js";
+import type { MessageRecord } from "../src/modules/message-capture/types.js";
+
+// Deterministic estimator: 1 token per character. Keeps the budget math
+// exact regardless of tiktoken behavior (the real estimator is injected at
+// the call site — see batchProcessor.ts).
+const estimate: TokenEstimator = (text: string) => text.length;
+
+function msg(id: string, content: string, createdAt: number): MessageRecord {
+  return {
+    id,
+    guild_id: "g",
+    channel_id: "c",
+    thread_id: null,
+    user_id: "u",
+    username: "user",
+    avatar_url: null,
+    content,
+    edited_content: null,
+    created_at: createdAt,
+    edited_at: null,
+    deleted_at: null,
+    type: "text",
+    is_reply: false,
+    is_forward: false,
+    is_crosspost: false,
+    reference_message_id: null,
+    reference_channel_id: null,
+    reference_guild_id: null,
+    metadata: null,
+  };
+}
+
+describe("pickBatchWithinBudget", () => {
+  const TOKENS_PER_MESSAGE = 50;
+
+  it("returns a contiguous chronological prefix — no gaps mid-timeline", () => {
+    // sizes: 100, 100, 400 (overflow), 10
+    const messages = [
+      msg("m1", "a".repeat(100), 1),
+      msg("m2", "b".repeat(100), 2),
+      msg("m3", "c".repeat(400), 3),
+      msg("m4", "d".repeat(10), 4),
+    ];
+    const batch = pickBatchWithinBudget(
+      messages,
+      500,
+      TOKENS_PER_MESSAGE,
+      estimate,
+    );
+
+    // m1(150)+m2(150)=300 fits; m3 would be 550 > 500 → stop.
+    // m4 must NOT be picked even though it alone fits (no timeline gap).
+    expect(batch.map((m) => m.id)).toEqual(["m1", "m2"]);
+  });
+
+  it("includes a message that exactly hits the budget", () => {
+    const messages = [msg("m1", "a".repeat(450), 1)];
+    const batch = pickBatchWithinBudget(
+      messages,
+      500,
+      TOKENS_PER_MESSAGE,
+      estimate,
+    );
+    expect(batch.map((m) => m.id)).toEqual(["m1"]);
+  });
+
+  it("returns empty when the first message alone exceeds the budget", () => {
+    const messages = [
+      msg("big", "x".repeat(1000), 1),
+      msg("m2", "y".repeat(10), 2),
+    ];
+    const batch = pickBatchWithinBudget(
+      messages,
+      500,
+      TOKENS_PER_MESSAGE,
+      estimate,
+    );
+    expect(batch).toHaveLength(0);
+  });
+
+  it("handles empty input", () => {
+    expect(
+      pickBatchWithinBudget([], 500, TOKENS_PER_MESSAGE, estimate),
+    ).toEqual([]);
+  });
+});