// IP.ipCheck as Java FILIUS runs it: every case in ip-check.cases.txt was run
// through Java (ip-check.java.json, tools/java-oracle) and must come out the
// same here.

import { readFileSync } from 'node:fs';
import { dirname, join } from 'node:path';
import { fileURLToPath } from 'node:url';
import { describe, expect, it } from 'vitest';
import { javaIpCheck, javaParseInt } from '../src/javaIp.js';

const here = dirname(fileURLToPath(import.meta.url));
const measured = JSON.parse(readFileSync(join(here, 'ip-check.java.json'), 'utf8')) as [string, string | null][];

/** The cases file's escapes: a backslash, `u` and four hex digits for one UTF-16 unit. */
function unescape(line: string): string {
  return line.replace(/\\u([0-9a-fA-F]{4})/g, (_, hex: string) => String.fromCharCode(Number.parseInt(hex, 16)));
}

describe('javaIpCheck against Java', () => {
  it('covers every line of the cases file', () => {
    const lines = readFileSync(join(here, 'ip-check.cases.txt'), 'ascii').split('\n').slice(0, -1);
    expect(measured.map(([line]) => line)).toEqual(lines);
  });

  for (const [line, expected] of measured) {
    it(JSON.stringify(line), () => {
      expect(javaIpCheck(unescape(line))).toBe(expected);
    });
  }
});

describe('javaParseInt', () => {
  it('keeps to the int range', () => {
    expect(javaParseInt('2147483647')).toBe(2147483647);
    expect(javaParseInt('-2147483648')).toBe(-2147483648);
    expect(javaParseInt('2147483648')).toBeUndefined();
    expect(javaParseInt('-2147483649')).toBeUndefined();
  });
});