import { describe, expect, it } from "vitest";
import type { Permissions } from "@/lib/auth/session";
import { resolveAuthorTagIds, statusChangeError } from "@/lib/permissions";

const perms = (overrides: Partial<Permissions> = {}): Permissions => ({
  createTags: false,
  publishPosts: false,
  unpublishPosts: false,
  deletePosts: false,
  approveComments: false,
  ...overrides,
});

describe("statusChangeError", () => {
  it("requires the publish permission to go draft -> published", () => {
    expect(statusChangeError(perms(), null, "published")).toMatch(/publish/);
    expect(statusChangeError(perms(), "draft", "published")).toMatch(/publish/);
    expect(statusChangeError(perms({ publishPosts: true }), "draft", "published")).toBeNull();
  });

  it("requires the unpublish permission to go published -> draft", () => {
    expect(statusChangeError(perms(), "published", "draft")).toMatch(/unpublish/);
    expect(
      statusChangeError(perms({ unpublishPosts: true }), "published", "draft"),
    ).toBeNull();
  });

  it("never blocks saves that keep the status", () => {
    expect(statusChangeError(perms(), "draft", "draft")).toBeNull();
    expect(statusChangeError(perms(), "published", "published")).toBeNull();
    expect(statusChangeError(perms(), null, "draft")).toBeNull();
  });
});

describe("resolveAuthorTagIds", () => {
  const allowed = new Set([1, 2]);

  it("rejects submissions outside the grants", () => {
    const result = resolveAuthorTagIds({
      submitted: [1, 3],
      existing: [],
      allowed,
      creatingTags: false,
    });
    expect(result).toHaveProperty("error");
  });

  it("requires at least one granted tag unless creating one", () => {
    expect(
      resolveAuthorTagIds({ submitted: [], existing: [], allowed, creatingTags: false }),
    ).toHaveProperty("error");
    expect(
      resolveAuthorTagIds({ submitted: [], existing: [], allowed, creatingTags: true }),
    ).toEqual({ tagIds: [] });
  });

  it("preserves admin-added tags the author cannot see", () => {
    // Post carries granted tag 1 and admin-added tag 9; the author's form
    // resubmits only tag 2. Tag 9 must survive.
    const result = resolveAuthorTagIds({
      submitted: [2],
      existing: [1, 9],
      allowed,
      creatingTags: false,
    });
    expect(result).toEqual({ tagIds: [2, 9] });
  });

  it("lets the author drop their own granted tags", () => {
    const result = resolveAuthorTagIds({
      submitted: [2],
      existing: [1, 2],
      allowed,
      creatingTags: false,
    });
    expect(result).toEqual({ tagIds: [2] });
  });
});