//------ Extensions of Number object ------

Number.formatFunctions = {count:0};
Number.prototype.NaN         = 'NaN';
Number.prototype.posInfinity = 'Infinity';
Number.prototype.negInfinity = '-Infinity';

Number.prototype.numberFormat = function(format, context) {
  if (isNaN(this) ) return Number.prototype.NaNstring;
  else if (this == +Infinity ) return Number.prototype.posInfinity;
  else if ( this == -Infinity) return Number.prototype.negInfinity;
  else if (Number.formatFunctions[format] == null) Number.createNewFormat(format);
  return this[Number.formatFunctions[format]](context);
}

Number.createNewFormat = function(format) {
  var funcName = "format" + Number.formatFunctions.count++;
  Number.formatFunctions[format] = funcName;
  var code = "Number.prototype." + funcName + " = function(context){\n";

  var formats = format.split(";");
  switch (formats.length) {
    case 1:
      code += Number.createTerminalFormat(format);
      break;
    case 2:
      code += "return (this < 0) ? this.numberFormat(\""
        + String.escape(formats[1])
        + "\", 1) : this.numberFormat(\""
        + String.escape(formats[0])
        + "\", 2);";
      break;
    case 3:
      code += "return (this < 0) ? this.numberFormat(\""
        + String.escape(formats[1])
        + "\", 1) : ((this == 0) ? this.numberFormat(\""
        + String.escape(formats[2])
        + "\", 2) : this.numberFormat(\""
        + String.escape(formats[0])
        + "\", 3));";
      break;
    default:
      code += "throw 'Too many semicolons in format string';";
      break;
  }
  eval(code + "}");
}

Number.createTerminalFormat = function(format) {
  // If there is no work to do, just return the literal value
  if (format.length > 0 && format.search(/[0#?]/) == -1)
    return "return '" + String.escape(format) + "';\n";

  // Negative values are always displayed without a minus sign when section separators are used.
  var code = "var val = (context == null) ? new Number(this) : Math.abs(this);\n";
  var thousands = false;
  var lodp = format;
  var rodp = "";
  var ldigits = 0;
  var rdigits = 0;
  var scidigits = 0;
  var scishowsign = false;
  var sciletter = "";
  // Look for (and remove) scientific notation instructions, which can be anywhere
  m = format.match(/\..*(e)([+-]?)(0+)/i);
  if (m) {
    sciletter = m[1];
    scishowsign = (m[2] == "+");
    scidigits = m[3].length;
    format = format.replace(/(e)([+-]?)(0+)/i, "");
  }
  // Split around the decimal point
  var m = format.match(/^([^.]*)\.(.*)$/);
  if (m) {
    lodp = m[1].replace(/\./g, "");
    rodp = m[2].replace(/\./g, "");
  }
  // Look for %
  if (format.indexOf('%') >= 0) code += "val *= 100;\n";
  // Look for comma-scaling to the left of the decimal point
  m = lodp.match(/(,+)(?:$|[^0#?,])/);
  if (m) code += "val /= " + Math.pow(1000, m[1].length) + "\n;";
  // Look for comma-separators
  if (lodp.search(/[0#?],[0#?]/) >= 0) thousands = true;
  // Nuke any extraneous commas
  if ((m) || thousands) lodp = lodp.replace(/,/g, "");
  // Figure out how many digits to the l/r of the decimal place
  m = lodp.match(/0[0#?]*/);
  if (m) ldigits = m[0].length;
  m = rodp.match(/[0#?]*/);
  if (m) rdigits = m[0].length;
  // Scientific notation takes precedence over rounding etc
  if (scidigits > 0) {
    code += "var sci = Number.toScientific(val,"
      + ldigits + ", " + rdigits + ", " + scidigits + ", " + scishowsign + ");\n"
      + "var arr = [sci.l, sci.r];\n";
  }
  else {
    // If there is no decimal point, round to nearest integer, AWAY from zero
    if (format.indexOf('.') < 0)
      code += "val = (val > 0) ? Math.ceil(val) : Math.floor(val);\n";
    // Numbers are rounded to the correct number of digits to the right of the decimal
    code += "var arr = val.round(" + rdigits + ").toFixed(" + rdigits + ").split('.');\n";
    // There are at least "ldigits" digits to the left of the decimal, so add zeros if needed.
    code += "arr[0] = (val < 0 ? '-' : '') + String.leftPad((val < 0 ? arr[0].substring(1) : arr[0]), "
        + ldigits + ", '0');\n";
  }
  // Add thousands separators
  if (thousands) code += "arr[0] = Number.addSeparators(arr[0]);\n";
  // Insert the digits into the formatting string.  On the LHS, extra digits are copied
  // into the result.  On the RHS, rounding has chopped them off.
  code += "arr[0] = Number.injectIntoFormat(arr[0].reverse(), '" + String.escape(lodp.reverse()) + "', true).reverse();\n";
  if (rdigits > 0) code += "arr[1] = Number.injectIntoFormat(arr[1], '" + String.escape(rodp) + "', false);\n";
  if (scidigits > 0) code += "arr[1] = arr[1].replace(/(\\d{" + rdigits + "})/, '$1" + sciletter + "' + sci.s);\n";
  return code + "return arr.join('.');\n";
}

Number.toScientific = function(val, ldigits, rdigits, scidigits, showsign) {
  var result = {l:"", r:"", s:""};
  var ex = "";
  // Make ldigits + rdigits significant figures
  var before = Math.abs(val).toFixed(ldigits + rdigits + 1).trim('0');
  // Move the decimal point to the right of all digits we want to keep,
  // and round the resulting value off
  var after = Math.round(new Number(before.replace(".", "").replace(new RegExp("(\\d{" + (ldigits + rdigits) + "})(.*)"), "$1.$2"))).toFixed(0);
  // Place the decimal point in the new string
  if (after.length >= ldigits)
    after = after.substring(0, ldigits) + "." + after.substring(ldigits);
  else
    after += '.';
  // Find how much the decimal point moved.  This is #places to LODP in the original
  // number, minus the #places in the new number.  There are no left-padded zeroes in
  // the new number, so the calculation for it is simpler than for the old number.
  result.s = (before.indexOf(".") - before.search(/[1-9]/)) - after.indexOf(".");
  // The exponent is off by 1 when it gets moved to the left.
  if (result.s < 0) result.s++;
  // Split the value around the decimal point and pad the parts appropriately.
  result.l = (val < 0 ? '-' : '') + String.leftPad(after.substring(0, after.indexOf(".")), ldigits, "0");
  result.r = after.substring(after.indexOf(".") + 1);
  if (result.s < 0) ex = "-";
  else if (showsign) ex = "+";
  result.s = ex + String.leftPad(Math.abs(result.s).toFixed(0), scidigits, "0");
  return result;
}

/*Number.prototype.round = function(decimals) {
  if (decimals > 0) {
    var m = this.toFixed(decimals + 1).match(new RegExp("(-?\\d*)\.(\\d{" + decimals + "})(\\d)\\d*$"));
    if (m && m.length)
      return new Number(m[1] + "." + String.leftPad(Math.round(m[2] + "." + m[3]), decimals, "0"));
  }
  return this;
}*/

Number.prototype.round = function(decimals) {
  if (decimals > 9)
    return (Math.round(this*Math.pow(10,decimals))/Math.pow(10,decimals));
  else
    return this;
}

Number.injectIntoFormat = function(val, format, stuffExtras) {
  var i = 0;
  var j = 0;
  var result = "";
  var revneg = val.charAt(val.length - 1) == '-';

  if ( revneg ) val = val.substring(0, val.length - 1);
  while (i < format.length && j < val.length && format.substring(i).search(/[0#?]/) >= 0) {
    if (format.charAt(i).match(/[0#?]/)) {
      // It's a formatting character; copy the corresponding character
      // in the value to the result
      if (val.charAt(j) != '-') result += val.charAt(j);
      else result += "0";
      j++;
    }
    else
      result += format.charAt(i);
    ++i;
  }
  if ( revneg && j == val.length )
    result += '-';
  if (j < val.length) {
    if (stuffExtras) result += val.substring(j);
    if ( revneg ) result += '-';
  }
  if (i < format.length) result += format.substring(i);
  return result.replace(/#/g, "").replace(/\?/g, " ");
}

Number.addSeparators = function(val) {
//  return val.reverse().replace(/(\d{3})/g, "$1,").reverse().replace(/^(-)?,/, "$1");
  return val.reverse().replace(/(\d{3})/g, "$1 ").reverse().replace(/^(-)?,/, "$1");
}