test run for user rebalance expenses feature, added safeguard for estimate exepenses acceptance in onboarding

api/tests/variable-categories.manual-rebalance.test.ts

@@ -0,0 +1,110 @@
+import request from "supertest";
+import { describe, it, expect, beforeAll, afterAll, beforeEach } from "vitest";
+import appFactory from "./appFactory";
+import { prisma, resetUser, ensureUser, U, cid, closePrisma } from "./helpers";
+import type { FastifyInstance } from "fastify";
+
+let app: FastifyInstance;
+
+beforeAll(async () => {
+  app = await appFactory();
+});
+
+afterAll(async () => {
+  if (app) await app.close();
+  await closePrisma();
+});
+
+async function seedBasics() {
+  await resetUser(U);
+  await ensureUser(U);
+  await prisma.variableCategory.createMany({
+    data: [
+      { id: cid("s"), userId: U, name: "savings", percent: 30, priority: 1, isSavings: true, balanceCents: 3000n },
+      { id: cid("f"), userId: U, name: "food", percent: 20, priority: 2, isSavings: false, balanceCents: 2000n },
+      { id: cid("g"), userId: U, name: "gas", percent: 30, priority: 3, isSavings: false, balanceCents: 3000n },
+      { id: cid("m"), userId: U, name: "misc", percent: 20, priority: 4, isSavings: false, balanceCents: 2000n },
+    ],
+  });
+  await prisma.budgetSession.create({
+    data: {
+      userId: U,
+      periodStart: new Date("2026-03-01T00:00:00Z"),
+      periodEnd: new Date("2026-04-01T00:00:00Z"),
+      totalBudgetCents: 10_000n,
+      allocatedCents: 0n,
+      fundedCents: 0n,
+      availableCents: 10_000n,
+    },
+  });
+}
+
+describe("manual rebalance", () => {
+  beforeEach(async () => {
+    await seedBasics();
+  });
+
+  it("rebalances when sums match available", async () => {
+    const cats = await prisma.variableCategory.findMany({ where: { userId: U }, orderBy: { priority: "asc" } });
+    const targets = cats.map((c) => ({ id: c.id, targetCents: 2500 })); // 4 * 2500 = 10000
+
+    const res = await request(app.server)
+      .post("/variable-categories/manual-rebalance")
+      .set("x-user-id", U)
+      .send({ targets });
+
+    expect(res.statusCode).toBe(200);
+    expect(res.body?.ok).toBe(true);
+    const updated = await prisma.variableCategory.findMany({ where: { userId: U } });
+    expect(updated.every((c) => Number(c.balanceCents) === 2500)).toBe(true);
+  });
+
+  it("rejects sum mismatch", async () => {
+    const cats = await prisma.variableCategory.findMany({ where: { userId: U }, orderBy: { priority: "asc" } });
+    const targets = cats.map((c, i) => ({ id: c.id, targetCents: i === 0 ? 5000 : 1000 })); // 5000 + 3*1000 = 8000
+
+    const res = await request(app.server)
+      .post("/variable-categories/manual-rebalance")
+      .set("x-user-id", U)
+      .send({ targets });
+
+    expect(res.statusCode).toBe(400);
+    expect(res.body?.code).toBe("SUM_MISMATCH");
+  });
+
+  it("requires savings confirmation when lowering below floor", async () => {
+    const cats = await prisma.variableCategory.findMany({ where: { userId: U }, orderBy: { priority: "asc" } });
+    // savings to 500 (below 20% of 10000 = 2000)
+    const targets = cats.map((c) => ({ id: c.id, targetCents: c.isSavings ? 500 : 3166 })); // 500 + 3*3166 = 9998 -> adjust
+    targets[1].targetCents += 2; // total 10000
+
+    const res = await request(app.server)
+      .post("/variable-categories/manual-rebalance")
+      .set("x-user-id", U)
+      .send({ targets });
+
+    expect(res.statusCode).toBe(400);
+    expect(res.body?.code).toBe("SAVINGS_FLOOR");
+
+    const resOk = await request(app.server)
+      .post("/variable-categories/manual-rebalance")
+      .set("x-user-id", U)
+      .send({ targets, forceLowerSavings: true });
+
+    expect(resOk.statusCode).toBe(200);
+  });
+
+  it("blocks >80% single category", async () => {
+    const cats = await prisma.variableCategory.findMany({ where: { userId: U }, orderBy: { priority: "asc" } });
+    const targets = cats.map((c, i) => ({ id: c.id, targetCents: i === 0 ? 9000 : 333 }));
+    targets[1].targetCents += 1; // sum 10000
+
+    const res = await request(app.server)
+      .post("/variable-categories/manual-rebalance")
+      .set("x-user-id", U)
+      .send({ targets });
+
+    expect(res.statusCode).toBe(400);
+    expect(res.body?.code).toBe("OVER_80_PERCENT");
+  });
+});