// Copyright (c) Meta Platforms, Inc. and affiliates.

import {describe, it, expect} from 'vitest';
import {render, screen, within} from '@testing-library/react';
import {Table} from '../../Table';
import type {TableColumn} from '../../types';
import {useTableRowIndex} from './useTableRowIndex';

interface Row extends Record<string, unknown> {
  id: string;
  name: string;
}

const data: Row[] = [
  {id: 'a', name: 'Alice'},
  {id: 'b', name: 'Bob'},
  {id: 'c', name: 'Carol'},
];

const columns: TableColumn<Row>[] = [{key: 'name', header: 'Name'}];

function Harness({
  rows = data,
  label,
  startFrom,
  useKey = false,
}: {
  rows?: Row[];
  label?: string;
  startFrom?: number;
  useKey?: boolean;
}) {
  const rowIndex = useTableRowIndex<Row>({
    data: rows,
    label,
    startFrom,
    getRowKey: useKey ? item => item.id : undefined,
  });
  return (
    <Table data={rows} columns={columns} idKey="id" plugins={{rowIndex}} />
  );
}

describe('useTableRowIndex', () => {
  it('prepends a header cell with the default label', () => {
    render(<Harness />);
    const headers = screen.getAllByRole('columnheader');
    // First column is the index column.
    expect(within(headers[0]).getByText('#')).toBeInTheDocument();
  });

  it('numbers rows 1..n by default', () => {
    render(<Harness />);
    expect(screen.getByText('1')).toBeInTheDocument();
    expect(screen.getByText('2')).toBeInTheDocument();
    expect(screen.getByText('3')).toBeInTheDocument();
  });

  it('respects startFrom', () => {
    render(<Harness startFrom={0} />);
    expect(screen.getByText('0')).toBeInTheDocument();
    expect(screen.getByText('2')).toBeInTheDocument();
    expect(screen.queryByText('3')).not.toBeInTheDocument();
  });

  it('supports a custom label', () => {
    render(<Harness label="Row" />);
    const headers = screen.getAllByRole('columnheader');
    expect(within(headers[0]).getByText('Row')).toBeInTheDocument();
  });

  it('numbers a single row', () => {
    render(<Harness rows={[{id: 'a', name: 'Alice'}]} />);
    const rows = screen.getAllByRole('row');
    expect(within(rows[1]).getByText('1')).toBeInTheDocument();
    expect(within(rows[1]).getByText('Alice')).toBeInTheDocument();
  });

  it('renders the index header with empty data and no row numbers', () => {
    render(<Harness rows={[]} />);
    const headers = screen.getAllByRole('columnheader');
    expect(within(headers[0]).getByText('#')).toBeInTheDocument();
    // No body rows → no ordinals.
    expect(screen.queryByText('1')).not.toBeInTheDocument();
  });

  it('renumbers when the data order changes (reference path)', () => {
    const {rerender} = render(<Harness rows={data} />);
    let rows = screen.getAllByRole('row');
    // rows[0] is the header row.
    expect(within(rows[1]).getByText('Alice')).toBeInTheDocument();
    expect(within(rows[1]).getByText('1')).toBeInTheDocument();

    // Reorder: Carol, Alice, Bob (same object identities, new order).
    rerender(<Harness rows={[data[2], data[0], data[1]]} />);
    rows = screen.getAllByRole('row');
    expect(within(rows[1]).getByText('Carol')).toBeInTheDocument();
    expect(within(rows[1]).getByText('1')).toBeInTheDocument();
    expect(within(rows[2]).getByText('Alice')).toBeInTheDocument();
    expect(within(rows[2]).getByText('2')).toBeInTheDocument();
  });

  it('renumbers when the data order changes (keyed path)', () => {
    // With getRowKey provided, the keyed lookup must still produce ordinals in
    // the new order. If the keyed branch were broken it would return undefined
    // and render no numbers — so this fails for the right reason.
    const {rerender} = render(<Harness rows={data} useKey />);
    let rows = screen.getAllByRole('row');
    expect(within(rows[1]).getByText('Alice')).toBeInTheDocument();
    expect(within(rows[1]).getByText('1')).toBeInTheDocument();

    rerender(<Harness rows={[data[1], data[2], data[0]]} useKey />);
    rows = screen.getAllByRole('row');
    expect(within(rows[1]).getByText('Bob')).toBeInTheDocument();
    expect(within(rows[1]).getByText('1')).toBeInTheDocument();
    expect(within(rows[3]).getByText('Alice')).toBeInTheDocument();
    expect(within(rows[3]).getByText('3')).toBeInTheDocument();
  });

  it('keyed path resolves ordinals across fresh object identities', () => {
    // Simulates a re-fetch: brand-new objects with the same ids. Keyed lookup
    // must map them correctly.
    const fresh: Row[] = [
      {id: 'a', name: 'Alice'},
      {id: 'b', name: 'Bob'},
    ];
    render(<Harness rows={fresh} useKey />);
    const rows = screen.getAllByRole('row');
    expect(within(rows[1]).getByText('1')).toBeInTheDocument();
    expect(within(rows[2]).getByText('2')).toBeInTheDocument();
  });
});