/**
 * Unit tests for getDashboardLayout — bug #27 regression guard.
 *
 * Verifies that getDashboardLayout returns null (not an empty layout) when the
 * stored dashboardLayout is an empty object or contains only unknown widget
 * types. This allows the client to fall back to the default stat-cards layout.
 */

import { describe, expect, it, vi } from "vitest";

vi.mock("../lib/audit.js", () => ({ createAuditEntry: vi.fn() }));
vi.mock("../lib/system-settings-runtime.js", () => ({ resolveSystemSettingsRuntime: vi.fn() }));

const { getDashboardLayout } = await import(
  "../router/user-self-service-procedure-support.js"
);

function makeCtx(dashboardLayout: unknown) {
  return {
    db: {
      user: {
        findUnique: vi.fn().mockResolvedValue(
          dashboardLayout !== undefined ? { dashboardLayout, updatedAt: new Date() } : null,
        ),
      },
    } as never,
    dbUser: { id: "user_1" },
    session: null,
  };
}

describe("getDashboardLayout — #27 regression", () => {
  it("returns null when dashboardLayout is null (new user)", async () => {
    const ctx = makeCtx(null);
    const result = await getDashboardLayout(ctx as never);
    expect(result.layout).toBeNull();
  });

  it("returns null when dashboardLayout is an empty object", async () => {
    const ctx = makeCtx({});
    const result = await getDashboardLayout(ctx as never);
    expect(result.layout).toBeNull();
  });

  it("returns null when dashboardLayout has no valid widget types", async () => {
    const ctx = makeCtx({
      version: 1,
      widgets: [{ type: "old-unknown-widget-type", id: "w1", x: 0, y: 0, w: 4, h: 3 }],
    });
    const result = await getDashboardLayout(ctx as never);
    expect(result.layout).toBeNull();
  });

  it("returns null when dashboardLayout has an empty widgets array", async () => {
    const ctx = makeCtx({ version: 2, gridCols: 12, widgets: [] });
    const result = await getDashboardLayout(ctx as never);
    expect(result.layout).toBeNull();
  });

  it("returns the layout when it contains at least one valid widget", async () => {
    const ctx = makeCtx({
      version: 2,
      gridCols: 12,
      widgets: [{ type: "stat-cards", id: "w1", x: 0, y: 0, w: 12, h: 3 }],
    });
    const result = await getDashboardLayout(ctx as never);
    expect(result.layout).not.toBeNull();
    expect(result.layout?.widgets).toHaveLength(1);
  });
});