var luxon = require('luxon');
var test = require('tap').test;
var CronDate = require('../lib/date');

test('parse cron date formats with local timezone', (t) => {
  // Some tests need the local offset to be compatible without invoking timezone management.
  // Local offset is dependent on what the system being tested on is
  var offset = new Date().getTimezoneOffset();
  var offsetHours = Math.abs(Math.floor(offset/60));
  var offsetMinutes = offset % 60;
  var offsetSign = offset < 0 ? '-' : '+';

  var expectedTime = new Date(2021, 0, 4, 10, 0, 0).toString();

  test('undefined date', (t) => {
    const realDate = new Date();
    var d = new CronDate();

    t.equal(d.toDate().toString(), realDate.toString());

    t.end();
  });

  test('JS Date', (t) => {
    var d = new CronDate(new Date(2021, 0, 4, 10, 0, 0));
    t.equal(d.toDate().toString(), expectedTime);

    t.end();
  });

  test('ISO 8601', (t) => {
    var d = new CronDate('2021-01-04T10:00:00');
    t.equal(d.toDate().toString(), expectedTime);

    t.end();
  });

  test('ISO 8601 date', (t) => {

    var d = new CronDate('2021-01-04');
    var expectedTime = new Date(2021, 0, 4, 0, 0, 0).toString();

    t.equal(d.toDate().toString(), expectedTime);

    t.end();
  });

  test('RFC2822', (t) => {
    var offsetString = offsetSign + String(offsetHours).padStart(2, 0) + String(offsetMinutes).padStart(2, 0);

    var d = new CronDate('Mon, 4 Jan 2021 10:00:00 ' + offsetString);
    t.equal(d.toDate().toString(), expectedTime);

    t.end();
  });

  test('RFC2822-like without timezone offset', (t) => {
    var d = new CronDate('Mon, 4 Jan 2021 10:00:00');
    t.equal(d.toDate().toString(), expectedTime);

    t.end();
  });

  test('SQL', (t) => {
    var d = new CronDate('2021-01-04 10:00:00');
    t.equal(d.toDate().toString(), expectedTime);

    t.end();
  });

  test('milliseconds', (t) => {
    var d = new CronDate(new Date('2021-01-04 10:00:00').valueOf());
    t.equal(d.toDate().toString(), expectedTime);

    t.end();
  });

  test('CronDate', (t) => {
    var date = new CronDate('Mon, 4 Jan 2021 10:00:00');
    var d = new CronDate(date);
    t.equal(d.toDate().toString(), expectedTime);

    t.end();
  });

  test('invalid', (t) => {
    t.throws(() => {
      var d = new CronDate('2021-01-4 10:00:00');
    });

    t.end();
  });

  t.end();
});

test('parse cron date formats with another timezone', (t) => {
  test('ISO 8601 without offset', (t) => {
    // implies format already in timezone
    var d = new CronDate('2021-01-04T10:00:00', 'Europe/Athens');
    t.equal(d.toISOString(), '2021-01-04T08:00:00.000Z');

    t.end();
  });

  test('ISO 8601 with non-local offset', (t) => {
    var d = new CronDate('2021-01-04T10:00:00+01:00', 'Europe/Athens');
    t.equal(d.toISOString(), '2021-01-04T09:00:00.000Z');

    t.end();
  });

  test('RFC2822 with non-local offset', (t) => {
    var d = new CronDate('Mon, 4 Jan 2021 10:00:00 +0100', 'Europe/Athens');
    t.equal(d.toISOString(), '2021-01-04T09:00:00.000Z');

    t.end();
  });

  test('milliseconds', (t) => {
    var date = luxon.DateTime.fromISO('2021-01-04T11:00:00.000+02:00').valueOf();
    var d = new CronDate(date, 'Europe/Athens');
    t.equal(d.toISOString(), '2021-01-04T09:00:00.000Z');

    t.end();
  });

  test('CronDate with same timezone', (t) => {
    var date = new CronDate('Mon, 4 Jan 2021 10:00:00', 'Europe/Athens');
    var d = new CronDate(date);
    t.equal(d.toISOString(), '2021-01-04T08:00:00.000Z');

    t.end();
  });

  test('CronDate with different timezone', (t) => {
    var date = new CronDate('Mon, 4 Jan 2021 10:00:00', 'America/New_York');
    var d = new CronDate(date, 'Europe/Athens');
    t.equal(d.toISOString(), '2021-01-04T15:00:00.000Z');

    t.end();
  });

  t.end('crondate input should');
});