/**
 * Ownership transfer settings page tests — admin bulk ownership transfer
 * (UI-Backlog module 16/16).
 *
 * Covers: admin gate, user selects, entity type toggles, submit gating,
 * transfer flow with result display.
 */
import React from 'react';
import { describe, it, expect, vi, beforeEach } from 'vitest';
import { render, screen, fireEvent, waitFor } from '@testing-library/react';
import { MemoryRouter } from 'react-router-dom';
import { SettingsOwnershipPage } from '@/pages/SettingsOwnership';

const transferMut = vi.fn().mockResolvedValue({
  message: 'Ownership transfer completed',
  results: { contacts: 5, workflows: 0 },
});

const makeUser = (id: string, name: string, email: string) => ({
  id,
  email,
  name,
  first_name: null,
  last_name: null,
  avatar_url: null,
  role: 'admin',
  role_id: null,
  is_active: true,
  tenant_id: 't-1',
});

let mockIsAdmin = true;
let mockUsers: unknown[] = [];
let mockLoading = false;

vi.mock('@/api/ownership', async (importOriginal) => {
  const actual = await importOriginal<typeof import('@/api/ownership')>();
  return {
    ...actual,
    useTransferOwnership: () => ({ mutate: transferMut, mutateAsync: transferMut, isPending: false }),
  };
});

vi.mock('@/api/users', () => ({
  useUsers: () => ({ data: { items: mockUsers, total: mockUsers.length }, isLoading: mockLoading }),
}));

vi.mock('@/store/authStore', () => ({
  useAuthStore: (selector: (state: { user: { is_system_admin: boolean } | null }) => unknown) =>
    selector({ user: { is_system_admin: mockIsAdmin } }),
}));

function renderPage() {
  return render(
    <MemoryRouter>
      <SettingsOwnershipPage />
    </MemoryRouter>,
  );
}

beforeEach(() => {
  vi.clearAllMocks();
  mockIsAdmin = true;
  mockLoading = false;
  mockUsers = [
    makeUser('11111111-1111-1111-1111-111111111111', 'Alte Mitarbeiterin', 'old@example.de'),
    makeUser('22222222-2222-2222-2222-222222222222', 'Nachfolger', 'new@example.de'),
  ];
  transferMut.mockResolvedValue({
    message: 'Ownership transfer completed',
    results: { contacts: 5, workflows: 0 },
  });
});

describe('SettingsOwnershipPage', () => {
  it('renders admin-only notice for non-admin users', () => {
    mockIsAdmin = false;
    renderPage();
    expect(screen.getByTestId('ownership-admin-only')).toBeInTheDocument();
    expect(screen.queryByTestId('ownership-form')).not.toBeInTheDocument();
  });

  it('renders the form with two user selects and 10 entity type buttons', () => {
    renderPage();
    expect(screen.getByTestId('ownership-form')).toBeInTheDocument();
    expect(screen.getByTestId('ownership-from')).toBeInTheDocument();
    expect(screen.getByTestId('ownership-to')).toBeInTheDocument();
    expect(screen.getByTestId('ownership-type-contacts')).toBeInTheDocument();
    expect(screen.getByTestId('ownership-type-notifications')).toBeInTheDocument();
  });

  it('submit is disabled without both users selected', () => {
    renderPage();
    const btn = screen.getByTestId('ownership-submit-btn') as HTMLButtonElement;
    expect(btn.disabled).toBe(true);
  });

  it('submit is disabled when from and to are the same user', () => {
    renderPage();
    const from = screen.getByTestId('ownership-from') as HTMLSelectElement;
    fireEvent.change(from, { target: { value: '11111111-1111-1111-1111-111111111111' } });
    const to = screen.getByTestId('ownership-to') as HTMLSelectElement;
    fireEvent.change(to, { target: { value: '11111111-1111-1111-1111-111111111111' } });
    const btn = screen.getByTestId('ownership-submit-btn') as HTMLButtonElement;
    expect(btn.disabled).toBe(true);
  });

  it('toggles entity types on click', () => {
    renderPage();
    const chip = screen.getByTestId('ownership-type-contacts');
    expect(chip.getAttribute('aria-pressed')).toBe('false');
    fireEvent.click(chip);
    expect(chip.getAttribute('aria-pressed')).toBe('true');
    fireEvent.click(chip);
    expect(chip.getAttribute('aria-pressed')).toBe('false');
  });

  it('transfers ownership after confirmation and shows the result', async () => {
    renderPage();
    const from = screen.getByTestId('ownership-from') as HTMLSelectElement;
    fireEvent.change(from, { target: { value: '11111111-1111-1111-1111-111111111111' } });
    const to = screen.getByTestId('ownership-to') as HTMLSelectElement;
    fireEvent.change(to, { target: { value: '22222222-2222-2222-2222-222222222222' } });
    fireEvent.click(screen.getByTestId('ownership-type-contacts'));

    const btn = screen.getByTestId('ownership-submit-btn') as HTMLButtonElement;
    expect(btn.disabled).toBe(false);
    fireEvent.click(btn);

    const confirmBtn = await screen.findByRole('button', { name: 'Bestätigen' });
    fireEvent.click(confirmBtn);

    await waitFor(() => {
      expect(transferMut).toHaveBeenCalledTimes(1);
    });
    expect(transferMut).toHaveBeenCalledWith({
      from_user_id: '11111111-1111-1111-1111-111111111111',
      to_user_id: '22222222-2222-2222-2222-222222222222',
      entity_types: ['contacts'],
    });

    await waitFor(() => {
      expect(screen.getByTestId('ownership-result')).toBeInTheDocument();
    });
  });
});