import { describe, expect, test } from "bun:test";
import type { V1PodTemplateSpec, V1ReplicaSet } from "@kubernetes/client-node";
import { stripPodTemplateHash, templateMatches } from "../../lib/rollback";

const template = (labels: Record<string, string> = {}): V1PodTemplateSpec => ({
  metadata: { name: "pod", labels },
  spec: {
    containers: [
      { name: "app", image: "registry/kuber/demo:latest@sha256:aaaa" },
    ],
  },
});

describe("rollback pod template handling", () => {
  test("strips the generated pod-template-hash label", () => {
    const result = stripPodTemplateHash(
      template({ app: "web", "pod-template-hash": "abc123" }),
    );
    expect(result.metadata?.labels).toEqual({ app: "web" });
  });

  test("clears labels entirely when only the hash is present", () => {
    const result = stripPodTemplateHash(
      template({ "pod-template-hash": "abc123" }),
    );
    expect(result.metadata?.labels).toBeUndefined();
  });

  test("returns a shallow copy without mutating the input", () => {
    const input = template({ app: "web" });
    const result = stripPodTemplateHash(input);
    expect(result).not.toBe(input);
    expect(input.metadata?.labels).toEqual({ app: "web" });
  });

  test("treats templates as equal when they differ only by hash", () => {
    expect(
      templateMatches(
        template({ app: "web", "pod-template-hash": "one" }),
        template({ app: "web", "pod-template-hash": "two" }),
      ),
    ).toBe(true);
  });

  test("treats templates as different when other fields differ", () => {
    const a = template({ app: "web" });
    const b = template({ app: "worker" });
    expect(templateMatches(a, b)).toBe(false);
  });

  test("matches undefined templates", () => {
    expect(templateMatches(undefined, undefined)).toBe(true);
    expect(templateMatches(template(), undefined)).toBe(false);
  });
});