import {
  formatLatencySec,
  metricToFormatter,
  styleNum,
  toClassName
} from './Utils.js';

// introduce some binary floating point rounding errors, like ya do
function float(num) {
  return num * 0.1 * 10;
}

describe('Utils', () => {
  describe('styleNum', () => {
    it('properly formats numbers', () => {
      let compare = (f, s) => expect(styleNum(float(f))).toEqual(s);
      compare(          1,          "1"       );
      compare(          2.20,       "2.2"     );
      compare(          3,          "3"       );
      compare(          4.4,        "4.4"     );
      compare(          5.0000001,  "5"       );
      compare(          7.6666667,  "7.67"    );
      compare(        123.456,      "123.46"  );
      compare(       1212.999999,   "1.213k"  );
      compare(       5329.333333,   "5.329k"  );
      compare(      16384.888,      "16.385k" );
      compare(     131042,          "131.042k");
      compare(    1048576,          "1.049M"  );
      compare(    2097152.1,        "2.097M"  );
      compare(   16777216,          "16.777M" );
      compare(  536870912,          "536.871M");
      compare( 1073741824,          "1.074G"  );
      compare(68719476736,          "68.719G" );
    });

    it('properly formats numbers with units and no truncation', () => {
      let compare = (f, s) => expect(styleNum(float(f), " RPS", false)).toEqual(s);
      compare(          1,          "1 RPS"               );
      compare(          2.20,       "2.2 RPS"             );
      compare(          3,          "3 RPS"               );
      compare(          4.4,        "4.4 RPS"             );
      compare(          5.0000001,  "5 RPS"               );
      compare(          7.6666667,  "7.67 RPS"            );
      compare(        123.456,      "123.46 RPS"          );
      compare(       1212.999999,   "1,213 RPS"           );
      compare(       5329.333333,   "5,329 RPS"           );
      compare(      16384.888,      "16,385 RPS"          );
      compare(     131042,          "131,042 RPS"         );
      compare(    1048576,          "1,048,576 RPS"       );
      compare(    2097152.1,        "2,097,152 RPS"       );
      compare(   16777216,          "16,777,216 RPS"      );
      compare(  536870912,          "536,870,912 RPS"     );
      compare( 1073741824,          "1,073,741,824 RPS"   );
      compare(68719476736,          "68,719,476,736 RPS"  );
    });
  });

  describe('Metric Formatters', () => {
    it('formats undefined input', () => {
      let undefinedMetric;
      expect(metricToFormatter["REQUEST_RATE"](undefinedMetric)).toEqual('---');
      expect(metricToFormatter["SUCCESS_RATE"](undefinedMetric)).toEqual('---');
      expect(metricToFormatter["LATENCY"](undefinedMetric)).toEqual('---');
    });

    it('formats requests with rounding and unit', () => {
      expect(metricToFormatter["REQUEST_RATE"](99)).toEqual('99 RPS');
      expect(metricToFormatter["REQUEST_RATE"](999)).toEqual('999 RPS');
      expect(metricToFormatter["REQUEST_RATE"](1000)).toEqual('1k RPS');
      expect(metricToFormatter["REQUEST_RATE"](4444)).toEqual('4.444k RPS');
      expect(metricToFormatter["REQUEST_RATE"](9999)).toEqual('9.999k RPS');
      expect(metricToFormatter["REQUEST_RATE"](99999)).toEqual('99.999k RPS');
    });

    it('formats subsecond latency as ms', () => {
      expect(metricToFormatter["LATENCY"](99)).toEqual('99 ms');
      expect(metricToFormatter["LATENCY"](999)).toEqual('999 ms');
    });

    it('formats latency greater than 1s as s', () => {
      expect(metricToFormatter["LATENCY"](1000)).toEqual('1.00 s');
      expect(metricToFormatter["LATENCY"](9999)).toEqual('10.0 s');
      expect(metricToFormatter["LATENCY"](99999)).toEqual('100 s');
    });

    it('formats success rate', () => {
      expect(metricToFormatter["SUCCESS_RATE"](0.012345)).toEqual('1.23%');
      expect(metricToFormatter["SUCCESS_RATE"](0.01)).toEqual('1.00%');
      expect(metricToFormatter["SUCCESS_RATE"](0.1)).toEqual('10.00%');
      expect(metricToFormatter["SUCCESS_RATE"](0.9999)).toEqual('99.99%');
      expect(metricToFormatter["SUCCESS_RATE"](4)).toEqual('400.00%');
    });

    it('formats latencies expressed as seconds into a more appropriate display unit', () => {
      expect(formatLatencySec("0.002837700")).toEqual("3 ms");
      expect(formatLatencySec("0.000")).toEqual("0 s");
      expect(formatLatencySec("0.000000797")).toEqual("1 µs");
      expect(formatLatencySec("0.000231910")).toEqual("232 µs");
      expect(formatLatencySec("0.000988600")).toEqual("989 µs");
      expect(formatLatencySec("0.005598200")).toEqual("6 ms");
      expect(formatLatencySec("3.029409200")).toEqual("3.03 s");
      expect(formatLatencySec("34.395600")).toEqual("34.4 s");
    });
  });

  describe('toClassName', () => {
    it('converts a string to a valid class name', () => {
      expect(toClassName('')).toEqual('');
      expect(toClassName('---')).toEqual('');
      expect(toClassName('foo/bar/baz')).toEqual('foo_bar_baz');
      expect(toClassName('FOOBAR')).toEqual('foobar');
      expect(toClassName('FooBar')).toEqual('foo_bar');

      // the perhaps unexpected number of spaces here are due to the fact that
      // _.lowerCase returns space separated words
      expect(toClassName('potato123yam0squash')).toEqual('potato_123_yam_0_squash');
      expect(toClassName('test/potato-e1af21-f3f3')).toEqual('test_potato_e_1_af_21_f_3_f_3');
    });
  });
});