runtime/bin/vmservice/observatory/lib/src/app/utils.dart

// Copyright (c) 2014, the Dart project authors.  Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.

part of app;

class Utils {
  static String formatPercent(num a, num total) {
      var percent = 100.0 * (a / total);
      return '${percent.toStringAsFixed(2)}%';
  }

  static String zeroPad(int value, int pad) {
    String prefix = "";
    while (pad > 1) {
      int pow10 = pow(10, pad - 1);
      if (value < pow10) {
        prefix = prefix + "0";
      }
      pad--;
    }
    return "${prefix}${value}";
  }

  static String formatCommaSeparated(int v) {
    const COMMA_EVERY = 1000;
    if (v < COMMA_EVERY) {
      return v.toString();
    }
    var mod = v % COMMA_EVERY;
    v ~/= COMMA_EVERY;
    var r = '${zeroPad(mod, 3)}';
    while (v > COMMA_EVERY) {
      mod = v % COMMA_EVERY;
      r = '${zeroPad(mod, 3)},$r';
      v ~/= COMMA_EVERY;
    }
    if (v != 0) {
      r = '$v,$r';
    }
    return r;
  }

  static String formatTimePrecise(double time) {
    if (time == null) {
      return "-";
    }
    const millisPerHour = 60 * 60 * 1000;
    const millisPerMinute = 60 * 1000;
    const millisPerSecond = 1000;

    var millis = (time * millisPerSecond).round();

    var hours = millis ~/ millisPerHour;
    millis = millis % millisPerHour;

    var minutes = millis ~/ millisPerMinute;
    millis = millis % millisPerMinute;

    var seconds = millis ~/ millisPerSecond;
    millis = millis % millisPerSecond;

    if (hours > 0) {
      return ("${zeroPad(hours,2)}"
              ":${zeroPad(minutes,2)}"
              ":${zeroPad(seconds,2)}"
              ".${zeroPad(millis,3)}");
    } else {
      return ("${zeroPad(minutes,2)}"
              ":${zeroPad(seconds,2)}"
              ".${zeroPad(millis,3)}");
    }
  }

  static String formatSize(int bytes) {
    const int digits = 1;
    const int bytesPerKB = 1024;
    const int bytesPerMB = 1024 * bytesPerKB;
    const int bytesPerGB = 1024 * bytesPerMB;
    const int bytesPerTB = 1024 * bytesPerGB;

    if (bytes < bytesPerKB) {
      return "${bytes}B";
    } else if (bytes < bytesPerMB) {
      return "${(bytes / bytesPerKB).toStringAsFixed(digits)}KB";
    } else if (bytes < bytesPerGB) {
      return "${(bytes / bytesPerMB).toStringAsFixed(digits)}MB";
    } else if (bytes < bytesPerTB) {
      return "${(bytes / bytesPerGB).toStringAsFixed(digits)}GB";
    } else {
      return "${(bytes / bytesPerTB).toStringAsFixed(digits)}TB";
    }
  }

  static String formatTime(double time) {
    if (time == null) {
      return "-";
    }
    const millisPerHour = 60 * 60 * 1000;
    const millisPerMinute = 60 * 1000;
    const millisPerSecond = 1000;

    var millis = (time * millisPerSecond).round();

    var hours = millis ~/ millisPerHour;
    millis = millis % millisPerHour;

    var minutes = millis ~/ millisPerMinute;
    millis = millis % millisPerMinute;

    var seconds = millis ~/ millisPerSecond;

    StringBuffer out = new StringBuffer();
    if (hours != 0) {
      return '${hours}h ${minutes}m ${seconds}s';
    }
    if (minutes != 0) {
      return '${minutes}m ${seconds}s';
    }
    return '${seconds}s';
  }

  static String formatSeconds(double x) {
    return x.toStringAsFixed(2);
  }

  static bool runningInJavaScript() => identical(1.0, 1);
}