logger.js

// General purpose logger.
// * Adds timestamps.
// * Retains line numbers.

(function loggerInitializer() {
  "use strict";
  // Stub common console methods when they are missing.
  var method,
      noop = function noop() {},
      methods = [
        'assert', 'clear', 'count', 'debug', 'dir', 'dirxml', 'error',
        'exception', 'group', 'groupCollapsed', 'groupEnd', 'info', 'log',
        'markTimeline', 'profile', 'profileEnd', 'table', 'time', 'timeEnd',
        'timeStamp', 'trace', 'warn'
      ],
      length = methods.length,
      console = (global.console = global.console || {});

  while (length--) {
      method = methods[length];

    // Only stub undefined methods.
    if (!console[method]) {
        console[method] = noop;
    }
  }

  function basic() {
    return {
      debug: function () { console.log(arguments[1])},
      error: function () { console.error(arguments[1])},
      info:  function () { console.log(arguments[1])},
      log:   function () { console.log(arguments[1])},
      warn:  function () { console.log(arguments[1])}
    }
  }

  function advanced(options) {
    options = typeof options !== 'undefined' ? options : {};

    var methods = {},
        dateString = noop,
        levelOptions = {
          debug: 'DeepPink',
          error: 'Red',
          info: 'DarkBlue',
          log: 'DarkGreen',
          warn: 'DarkOrange'
        };

    dateString.toString = function toString() {
      var datetime = new Date();
      return datetime.getHours() + ':' + datetime.getMinutes() + ':' + datetime.getMilliseconds();
    };

    Object.keys(levelOptions).forEach(function (level) {
      // Stub our debug statements in production.
      if (level === 'debug' && options.debug) {

        return methods[level] = function () {};
      }

      methods[level] = console[level].bind(
        console,
        "%c[%s] %c[%s] %c[%s]",
        ("color: " + levelOptions[level]),
        level,
        "color: black",
        dateString,
        "color: blue")
    });

    return methods;
  }

  // IE8 is pain.
  if (navigator.userAgent.match(/msie/i)) {
    global.Logger = new basic();
  } else {
    global.Logger = new advanced({ debug: !global.logDebugStatements });
  }
})();