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

import {
  evaluateBundleBudget,
  evaluateFieldBudget,
  evaluateLabBudget,
  percentile75,
} from "../../src/application/policies/performance-budgets.ts";

describe("performance budgets", () => {
  it("rejects initial and lazy JavaScript above their named limits", () => {
    const thresholds = {
      initialJsGzipBytes: 200,
      lazyChunkGzipBytes: 120,
    };
    expect(
      evaluateBundleBudget(
        { initialJsGzipBytes: 201, lazyChunks: [] },
        thresholds,
      ).passed,
    ).toBe(false);
    expect(
      evaluateBundleBudget(
        {
          initialJsGzipBytes: 100,
          lazyChunks: [{ path: "lazy.js", gzipBytes: 121 }],
        },
        thresholds,
      ).passed,
    ).toBe(false);
  });

  it("fails lab evidence when context is absent or a metric is over budget", () => {
    const thresholds = { lcpMs: 2500, cls: 0.1, namedInteractionMs: 200 };
    expect(
      evaluateLabBudget(
        { metrics: { lcpMs: 1000, cls: 0, namedInteractionMs: 50 } },
        thresholds,
      ),
    ).toMatchObject({ passed: false });
    expect(
      evaluateLabBudget(
        {
          context: {
            runner: {},
            browser: {},
            viewport: {},
            network: {},
            cpu: {},
            cache: {},
            build: {},
          },
          metrics: { lcpMs: 2501, cls: 0, namedInteractionMs: 50 },
        },
        thresholds,
      ).passed,
    ).toBe(false);
  });

  it("uses the nearest-rank p75 and fails closed while sample minimum is deferred", () => {
    expect(percentile75([4, 1, 3, 2])).toBe(3);
    expect(
      evaluateFieldBudget(
        {
          metrics: { p75LcpMs: 1000, p75Cls: 0.01, p75InpMs: 50 },
          eligibleSamples: 100,
        },
        {
          p75LcpMs: 2500,
          p75Cls: 0.1,
          p75InpMs: 200,
          minimumEligibleSamples: null,
        },
      ),
    ).toEqual({ status: "FAIL_UNVERIFIED", passed: false });
  });
});