✏️ Editing: jquery.alphanum.js

// jscs:disable
// jshint ignore: start

/********************************************************************
 * Limit the characters that may be entered in a text field
 * Common options: alphanumeric, alphabetic or numeric
 * Kevin Sheedy, 2012
 * http://github.com/KevinSheedy/jquery.alphanum
 *********************************************************************/

(function( $ ) {
	// API ///////////////////////////////////////////////////////////////////
	$.fn.alphanum = function( settings ) {

var combinedSettings = getCombinedSettingsAlphaNum( settings );

var $collection = this;

setupEventHandlers( $collection, trimAlphaNum, combinedSettings );

return this;
	};

$.fn.alpha = function( settings ) {

var defaultAlphaSettings = getCombinedSettingsAlphaNum( 'alpha' );
		var combinedSettings = getCombinedSettingsAlphaNum( settings, defaultAlphaSettings );

var $collection = this;

setupEventHandlers( $collection, trimAlphaNum, combinedSettings );

return this;
	};

$.fn.numeric = function( settings ) {

var combinedSettings = getCombinedSettingsNum( settings );
		var $collection = this;

setupEventHandlers( $collection, trimNum, combinedSettings );

$collection.on(
			'blur',
			function() {
				numericField_Blur( this, settings );
			}
		);

return this;
	};

// End of API /////////////////////////////////////////////////////////////

// Start Settings ////////////////////////////////////////////////////////

var DEFAULT_SETTINGS_ALPHANUM = {
		allow: '',   // Allow extra characters
		disallow: '',   // Disallow extra characters
		allowSpace: true, // Allow the space character
		allowNumeric: true, // Allow digits 0-9
		allowUpper: true, // Allow upper case characters
		allowLower: true, // Allow lower case characters
		allowCaseless: true, // Allow characters that don't have both upper & lower variants - eg Arabic or Chinese
		allowLatin: true, // a-z A-Z
		allowOtherCharSets: true, // eg �, �, Arabic, Chinese etc
		maxLength: NaN   // eg Max Length
	};

var DEFAULT_SETTINGS_NUM = {
		allowPlus: false, // Allow the + sign
		allowMinus: true,  // Allow the - sign
		allowThouSep: true,  // Allow the thousands separator, default is the comma eg 12,000
		allowDecSep: true,  // Allow the decimal separator, default is the fullstop eg 3.141
		allowLeadingSpaces: false, maxDigits: NaN,   // The max number of digits
		maxDecimalPlaces: NaN,   // The max number of decimal places
		maxPreDecimalPlaces: NaN,   // The max number digits before the decimal point
		max: NaN,   // The max numeric value allowed
		min: NaN    // The min numeric value allowed
	};

// Some pre-defined groups of settings for convenience
	var CONVENIENCE_SETTINGS_ALPHANUM = {
		'alpha': {
			allowNumeric: false
		}, 'upper': {
			allowNumeric: false, allowUpper: true, allowLower: false, allowCaseless: true
		}, 'lower': {
			allowNumeric: false, allowUpper: false, allowLower: true, allowCaseless: true
		}
	};

// Some pre-defined groups of settings for convenience
	var CONVENIENCE_SETTINGS_NUMERIC = {
		'integer': {
			allowPlus: false, allowMinus: true, allowThouSep: false, allowDecSep: false
		}, 'positiveInteger': {
			allowPlus: false, allowMinus: false, allowThouSep: false, allowDecSep: false
		}
	};

var BLACKLIST = getBlacklistAscii() + getBlacklistNonAscii();
	var THOU_SEP = ',';
	var DEC_SEP = '.';
	var DIGITS = getDigitsMap();
	var LATIN_CHARS = getLatinCharsSet();

// Return the blacklisted special chars that are encodable using 7-bit ascii
	function getBlacklistAscii() {
		var blacklist = '!@#$%^&*()+=[]\\\';,/{}|":<>?~`.-_';
		blacklist += ' '; // 'Space' is on the blacklist but can be enabled using the 'allowSpace' config entry
		return blacklist;
	}

// Return the blacklisted special chars that are NOT encodable using 7-bit ascii
	// We want this .js file to be encoded using 7-bit ascii so it can reach the widest possible audience
	// Higher order chars must be escaped eg "\xAC"
	// Not too worried about comments containing higher order characters for now (let's wait and see if it becomes a problem)
	function getBlacklistNonAscii() {
		var blacklist = '\xAC'     // �
			+ '\u20AC'   // �
			+ '\xA3'     // �
			+ '\xA6'     // �
		;
		return blacklist;
	}

// End Settings ////////////////////////////////////////////////////////

// Implementation details go here ////////////////////////////////////////////////////////

function setupEventHandlers( $textboxes, trimFunction, settings ) {

$textboxes.each( function() {

var $textbox = $( this );

$textbox.on( 'keyup change paste', function( e ) {

var pastedText = '';

if ( e.originalEvent && e.originalEvent.clipboardData && e.originalEvent.clipboardData.getData ) pastedText = e.originalEvent.clipboardData.getData(
					'text/plain' );

// setTimeout is necessary for handling the 'paste' event
				setTimeout( function() {
					trimTextbox( $textbox, trimFunction, settings, pastedText );
				}, 0 );
			} );

$textbox.on( 'keypress', function( e ) {

// Determine which key is pressed.
				// If it's a control key, then allow the event's default action to occur eg backspace, tab
				var charCode = !e.charCode ? e.which : e.charCode;
				if ( isControlKey( charCode ) || e.ctrlKey || e.metaKey ) // cmd on MacOS
					return;

var newChar = String.fromCharCode( charCode );

// Determine if some text was selected / highlighted when the key was pressed
				var selectionObject = $textbox.selection();
				var start = selectionObject.start;
				var end = selectionObject.end;

var textBeforeKeypress = $textbox.val();

// The new char may be inserted:
				//  1) At the start
				//  2) In the middle
				//  3) At the end
				//  4) User highlights some text and then presses a key which would replace the highlighted text
				//
				// Here we build the string that would result after the keypress.
				// If the resulting string is invalid, we cancel the event.
				// Unfortunately, it isn't enough to just check if the new char is valid because some chars
				// are position sensitive eg the decimal point '.'' or the minus sign '-'' are only valid in certain positions.
				var potentialTextAfterKeypress = textBeforeKeypress.substring( 0, start ) + newChar + textBeforeKeypress.substring( end );
				var validatedText = trimFunction( potentialTextAfterKeypress, settings );

// If the keypress would cause the textbox to contain invalid characters, then cancel the keypress event
				if ( validatedText != potentialTextAfterKeypress ) e.preventDefault();
			} );
		} );

}

// Ensure the text is a valid number when focus leaves the textbox
	// This catches the case where a user enters '-' or '.' without entering any digits
	function numericField_Blur( inputBox, settings ) {
		var fieldValueNumeric = parseFloat( $( inputBox ).val() );
		var $inputBox = $( inputBox );

if ( isNaN( fieldValueNumeric ) ) {
			$inputBox.val( '' );
			return;
		}

if ( isNumeric( settings.min ) && fieldValueNumeric < settings.min ) $inputBox.val( '' );

if ( isNumeric( settings.max ) && fieldValueNumeric > settings.max ) $inputBox.val( '' );
	}

function isNumeric( value ) {
		return !isNaN( value );
	}

function isControlKey( charCode ) {

if ( charCode >= 32 ) return false;
		if ( charCode == 10 ) return false;
		if ( charCode == 13 ) return false;

return true;
	}

// One way to prevent a character being entered is to cancel the keypress event.
	// However, this gets messy when you have to deal with things like copy paste which isn't a keypress.
	// Which event gets fired first, keypress or keyup? What about IE6 etc etc?
	// Instead, it's easier to allow the 'bad' character to be entered and then to delete it immediately after.

function trimTextbox( $textBox, trimFunction, settings, pastedText ) {

var inputString = $textBox.val();

if ( inputString == '' && pastedText.length > 0 ) inputString = pastedText;

var outputString = trimFunction( inputString, settings );

if ( inputString == outputString ) return;

var caretPos = $textBox.alphanum_caret();

$textBox.val( outputString );

//Reset the caret position
		if ( inputString.length == (outputString.length + 1) ) $textBox.alphanum_caret( caretPos - 1 ); else $textBox.alphanum_caret( caretPos );
	}

function getCombinedSettingsAlphaNum( settings, defaultSettings ) {
		if ( typeof defaultSettings == 'undefined' ) defaultSettings = DEFAULT_SETTINGS_ALPHANUM;
		var userSettings, combinedSettings = {};
		if ( typeof settings === 'string' ) userSettings = CONVENIENCE_SETTINGS_ALPHANUM[settings]; else if ( typeof settings == 'undefined' ) userSettings = {}; else userSettings = settings;

$.extend( combinedSettings, defaultSettings, userSettings );

if ( typeof combinedSettings.blacklist == 'undefined' ) combinedSettings.blacklistSet = getBlacklistSet(
			combinedSettings.allow, combinedSettings.disallow );

return combinedSettings;
	}

function getCombinedSettingsNum( settings ) {
		var userSettings, combinedSettings = {};
		if ( typeof settings === 'string' ) userSettings = CONVENIENCE_SETTINGS_NUMERIC[settings]; else if ( typeof settings == 'undefined' ) userSettings = {}; else userSettings = settings;

$.extend( combinedSettings, DEFAULT_SETTINGS_NUM, userSettings );

return combinedSettings;
	}

// This is the heart of the algorithm
	function alphanum_allowChar( validatedStringFragment, Char, settings ) {

if ( settings.maxLength && validatedStringFragment.length >= settings.maxLength ) return false;

if ( settings.allow.indexOf( Char ) >= 0 ) return true;

if ( settings.allowSpace && (Char == ' ') ) return true;

if ( settings.blacklistSet.contains( Char ) ) return false;

if ( !settings.allowNumeric && DIGITS[Char] ) return false;

if ( !settings.allowUpper && isUpper( Char ) ) return false;

if ( !settings.allowLower && isLower( Char ) ) return false;

if ( !settings.allowCaseless && isCaseless( Char ) ) return false;

if ( !settings.allowLatin && LATIN_CHARS.contains( Char ) ) return false;

if ( !settings.allowOtherCharSets ) {
			if ( DIGITS[Char] || LATIN_CHARS.contains( Char ) ) return true; else return false;
		}

return true;
	}

function numeric_allowChar( validatedStringFragment, Char, settings ) {

if ( DIGITS[Char] ) {

if ( isMaxDigitsReached( validatedStringFragment, settings ) ) return false;

if ( isMaxPreDecimalsReached( validatedStringFragment, settings ) ) return false;

if ( isMaxDecimalsReached( validatedStringFragment, settings ) ) return false;

if ( isGreaterThanMax( validatedStringFragment + Char, settings ) ) return false;

if ( isLessThanMin( validatedStringFragment + Char, settings ) ) return false;

return true;
		}

if ( settings.allowPlus && Char == '+' && validatedStringFragment == '' ) return true;

if ( settings.allowMinus && Char == '-' && validatedStringFragment == '' ) return true;

if ( Char == THOU_SEP && settings.allowThouSep && allowThouSep( validatedStringFragment, Char ) ) return true;

if ( Char == DEC_SEP ) {
			// Only one decimal separator allowed
			if ( validatedStringFragment.indexOf( DEC_SEP ) >= 0 ) return false;
			if ( settings.allowDecSep ) return true;
		}

return false;
	}

function countDigits( string ) {

// Error handling, nulls etc
		string = string + '';

// Count the digits
		return string.replace( /[^0-9]/g, '' ).length;
	}

function isMaxDigitsReached( string, settings ) {

var maxDigits = settings.maxDigits;

if ( maxDigits == '' || isNaN( maxDigits ) ) return false; // In this case, there is no maximum

var numDigits = countDigits( string );

if ( numDigits >= maxDigits ) return true;

return false;
	}

function isMaxDecimalsReached( string, settings ) {

var maxDecimalPlaces = settings.maxDecimalPlaces;

if ( maxDecimalPlaces == '' || isNaN( maxDecimalPlaces ) ) return false; // In this case, there is no maximum

var indexOfDecimalPoint = string.indexOf( DEC_SEP );

if ( indexOfDecimalPoint == -1 ) return false;

var decimalSubstring = string.substring( indexOfDecimalPoint );
		var numDecimals = countDigits( decimalSubstring );

if ( numDecimals >= maxDecimalPlaces ) return true;

return false;
	}

function isMaxPreDecimalsReached( string, settings ) {

var maxPreDecimalPlaces = settings.maxPreDecimalPlaces;

if ( maxPreDecimalPlaces == '' || isNaN( maxPreDecimalPlaces ) ) return false; // In this case, there is no maximum

var indexOfDecimalPoint = string.indexOf( DEC_SEP );

if ( indexOfDecimalPoint >= 0 ) return false;

var numPreDecimalDigits = countDigits( string );

if ( numPreDecimalDigits >= maxPreDecimalPlaces ) return true;

return false;
	}

function isGreaterThanMax( numericString, settings ) {

if ( !settings.max || settings.max < 0 ) return false;

var outputNumber = parseFloat( numericString );
		if ( outputNumber > settings.max ) return true;

return false;
	}

function isLessThanMin( numericString, settings ) {

if ( !settings.min || settings.min > 0 ) return false;

var outputNumber = parseFloat( numericString );
		if ( outputNumber < settings.min ) return true;

return false;
	}

/********************************
	 * Trims a string according to the settings provided
	 ********************************/
	function trimAlphaNum( inputString, settings ) {

if ( typeof inputString != 'string' ) return inputString;

var inChars = inputString.split( '' );
		var outChars = [];
		var i = 0;
		var Char;

for ( i = 0; i < inChars.length; i++ ) {
			Char = inChars[i];
			var validatedStringFragment = outChars.join( '' );
			if ( alphanum_allowChar( validatedStringFragment, Char, settings ) ) outChars.push( Char );
		}

return outChars.join( '' );
	}

function trimNum( inputString, settings ) {
		if ( typeof inputString != 'string' ) return inputString;

var inChars = inputString.split( '' );
		var outChars = [];
		var i = 0;
		var Char;

for ( i = 0; i < inChars.length; i++ ) {
			Char = inChars[i];
			var validatedStringFragment = outChars.join( '' );
			if ( numeric_allowChar( validatedStringFragment, Char, settings ) ) outChars.push( Char );
		}

return outChars.join( '' );
	}

function removeUpperCase( inputString ) {
		var charArray = inputString.split( '' );
		var i = 0;
		var outputArray = [];
		var Char;

for ( i = 0; i < charArray.length; i++ ) {
			Char = charArray[i];
		}
	}

function removeLowerCase( inputString ) {

}

function isUpper( Char ) {
		var upper = Char.toUpperCase();
		var lower = Char.toLowerCase();

if ( (Char == upper) && (upper != lower) ) return true; else return false;
	}

function isLower( Char ) {
		var upper = Char.toUpperCase();
		var lower = Char.toLowerCase();

if ( (Char == lower) && (upper != lower) ) return true; else return false;
	}

function isCaseless( Char ) {
		if ( Char.toUpperCase() == Char.toLowerCase() ) return true; else return false;
	}

function getBlacklistSet( allow, disallow ) {

var setOfBadChars = new Set( BLACKLIST + disallow );
		var setOfGoodChars = new Set( allow );

var blacklistSet = setOfBadChars.subtract( setOfGoodChars );

return blacklistSet;
	}

function getDigitsMap() {
		var array = '0123456789'.split( '' );
		var map = {};
		var i = 0;
		var digit;

for ( i = 0; i < array.length; i++ ) {
			digit = array[i];
			map[digit] = true;
		}

return map;
	}

function getLatinCharsSet() {
		var lower = 'abcdefghijklmnopqrstuvwxyz';
		var upper = lower.toUpperCase();
		var azAZ = new Set( lower + upper );

return azAZ;
	}

function allowThouSep( currentString, Char ) {

// Can't start with a THOU_SEP
		if ( currentString.length == 0 ) return false;

// Can't have a THOU_SEP anywhere after a DEC_SEP
		var posOfDecSep = currentString.indexOf( DEC_SEP );
		if ( posOfDecSep >= 0 ) return false;

var posOfFirstThouSep = currentString.indexOf( THOU_SEP );

// Check if this is the first occurrence of a THOU_SEP
		if ( posOfFirstThouSep < 0 ) return true;

var posOfLastThouSep = currentString.lastIndexOf( THOU_SEP );
		var charsSinceLastThouSep = currentString.length - posOfLastThouSep - 1;

// Check if there has been 3 digits since the last THOU_SEP
		if ( charsSinceLastThouSep < 3 ) return false;

var digitsSinceFirstThouSep = countDigits( currentString.substring( posOfFirstThouSep ) );

// Check if there has been a multiple of 3 digits since the first THOU_SEP
		if ( (digitsSinceFirstThouSep % 3) > 0 ) return false;

return true;
	}

////////////////////////////////////////////////////////////////////////////////////
	// Implementation of a Set
	////////////////////////////////////////////////////////////////////////////////////
	function Set( elems ) {
		if ( typeof elems == 'string' ) this.map = stringToMap( elems ); else this.map = {};
	}

Set.prototype.add = function( set ) {

var newSet = this.clone();

for ( var key in set.map ) newSet.map[key] = true;

return newSet;
	};

Set.prototype.subtract = function( set ) {

var newSet = this.clone();

for ( var key in set.map ) delete newSet.map[key];

return newSet;
	};

Set.prototype.contains = function( key ) {
		if ( this.map[key] ) return true; else return false;
	};

Set.prototype.clone = function() {
		var newSet = new Set();

for ( var key in this.map ) newSet.map[key] = true;

return newSet;
	};

////////////////////////////////////////////////////////////////////////////////////

function stringToMap( string ) {
		var map = {};
		var array = string.split( '' );
		var i = 0;
		var Char;

for ( i = 0; i < array.length; i++ ) {
			Char = array[i];
			map[Char] = true;
		}

return map;
	}

// Backdoor for testing
	$.fn.alphanum.backdoorAlphaNum = function( inputString, settings ) {
		var combinedSettings = getCombinedSettingsAlphaNum( settings );

return trimAlphaNum( inputString, combinedSettings );
	};

$.fn.alphanum.backdoorNumeric = function( inputString, settings ) {
		var combinedSettings = getCombinedSettingsNum( settings );

return trimNum( inputString, combinedSettings );
	};

$.fn.alphanum.setNumericSeparators = function( settings ) {

if ( settings.thousandsSeparator.length != 1 ) return;

if ( settings.decimalSeparator.length != 1 ) return;

THOU_SEP = settings.thousandsSeparator;
		DEC_SEP = settings.decimalSeparator;
	};

})( jQuery );

//Include the 3rd party lib: jquery.caret.js

// Set caret position easily in jQuery
// Written by and Copyright of Luke Morton, 2011
// Licensed under MIT
(function( $ ) {
	// Behind the scenes method deals with browser
	// idiosyncrasies and such
	function caretTo( el, index ) {
		if ( el.createTextRange ) {
			var range = el.createTextRange();
			range.move( 'character', index );
			range.select();
		} else if ( el.selectionStart != null ) {
			el.trigger( 'focus' );
			el.setSelectionRange( index, index );
		}
	};

// Another behind the scenes that collects the
	// current caret position for an element

// TODO: Get working with Opera
	function caretPos( el ) {
		if ( 'selection' in document ) {
			var range = el.createTextRange();
			try {
				range.setEndPoint( 'EndToStart', document.selection.createRange() );
			} catch ( e ) {
				// Catch IE failure here, return 0 like
				// other browsers
				return 0;
			}
			return range.text.length;
		} else if ( el.selectionStart != null ) {
			return el.selectionStart;
		}
	};

// The following methods are queued under fx for more
	// flexibility when combining with $.fn.delay() and
	// jQuery effects.

// Set caret to a particular index
	$.fn.alphanum_caret = function( index, offset ) {
		if ( typeof (index) === 'undefined' ) {
			return caretPos( this.get( 0 ) );
		}

return this.queue( function( next ) {
			if ( isNaN( index ) ) {
				var i = $( this ).val().indexOf( index );

if ( offset === true ) {
					i += index.length;
				} else if ( typeof (offset) !== 'undefined' ) {
					i += offset;
				}

caretTo( this, i );
			} else {
				caretTo( this, index );
			}

next();
		} );
	};
}( jQuery ));

/**********************************************************
 * Selection Library
 * Used to determine what text is highlighted in the textbox before a key is pressed.
 * http://donejs.com/docs.html#!jQuery.fn.selection
 * https://github.com/jupiterjs/jquerymx/blob/master/dom/selection/selection.js
 ***********************************************************/
(function( $ ) {
	var convertType = function( type ) {
			return type.replace( /([a-z])([a-z]+)/gi, function( all, first, next ) {
				return first + next.toLowerCase();
			} ).replace( /_/g, '' );
		}, reverse = function( type ) {
			return type.replace( /^([a-z]+)_TO_([a-z]+)/i, function( all, first, last ) {
				return last + '_TO_' + first;
			} );
		}, getWindow = function( element ) {
			return element ? element.ownerDocument.defaultView || element.ownerDocument.parentWindow : window;
		}, // A helper that uses range to abstract out getting the current start and endPos.
		getElementsSelection = function( el, win ) {
			var current = $.Range.current( el ).clone(), entireElement = $.Range( el ).select( el );

if ( !current.overlaps( entireElement ) ) {
				return null;
			}
			// we need to check if it starts before our element ...
			if ( current.compare( 'START_TO_START', entireElement ) < 1 ) {
				var startPos = 0;
				// we should move current ...
				current.move( 'START_TO_START', entireElement );
			} else {
				var fromElementToCurrent = entireElement.clone();
				fromElementToCurrent.move( 'END_TO_START', current );

startPos = fromElementToCurrent.toString().length;
			}

// now we need to make sure current isn't to the right of us ...
			var endPos;

if ( current.compare( 'END_TO_END', entireElement ) >= 0 ) {
				endPos = entireElement.toString().length;
			} else {
				endPos = startPos + current.toString().length;
			}

return {
				start: startPos, end: endPos
			};
		}, getSelection = function( el ) {
			// use selectionStart if we can.
			var win = getWindow( el );

if ( el.selectionStart !== undefined ) {
				if ( document.activeElement && document.activeElement !== el && el.selectionStart === el.selectionEnd && el.selectionStart === 0 ) {
					return {start: el.value.length, end: el.value.length};
				}

return {start: el.selectionStart, end: el.selectionEnd};
			} else if ( win.getSelection ) {
				return getElementsSelection( el, win );
			} else {
				try {
					//try 2 different methods that work differently
					// one should only work for input elements, but sometimes doesn't
					// I don't know why this is, or what to detect
					if ( el.nodeName.toLowerCase() === 'input' ) {
						var real = getWindow( el ).document.selection.createRange(), r = el.createTextRange();

r.setEndPoint( 'EndToStart', real );

var start = r.text.length;

return {
							start: start, end: start + real.text.length
						};
					} else {
						var res = getElementsSelection( el, win );
						if ( !res ) {
							return res;
						}

// we have to clean up for ie's textareas
						var current = $.Range.current().clone(), r2 = current.clone().collapse().range,
							r3 = current.clone().collapse( false ).range;

r2.moveStart( 'character', -1 );
						r3.moveStart( 'character', -1 );

// if we aren't at the start, but previous is empty, we are at start of newline
						if ( res.startPos !== 0 && r2.text === '' ) {
							res.startPos += 2;
						}

// do a similar thing for the end of the textarea
						if ( res.endPos !== 0 && r3.text === '' ) {
							res.endPos += 2;
						}

return res;
					}
				} catch ( e ) {
					return {start: el.value.length, end: el.value.length};
				}
			}
		}, select = function( el, start, end ) {
			var win = getWindow( el );

if ( el.setSelectionRange ) {
				if ( end === undefined ) {
					el.trigger( 'focus' );
					el.setSelectionRange( start, start );
				} else {
					el.select();
					el.selectionStart = start;
					el.selectionEnd = end;
				}
			} else if ( el.createTextRange ) {
				var r = el.createTextRange();
				r.moveStart( 'character', start );
				end = end || start;
				r.moveEnd( 'character', end - el.value.length );

r.select();
			} else if ( win.getSelection ) {
				var doc = win.document, sel = win.getSelection(), range = doc.createRange(),
					ranges = [start, end !== undefined ? end : start];
				getCharElement( [el], ranges );
				range.setStart( ranges[0].el, ranges[0].count );
				range.setEnd( ranges[1].el, ranges[1].count );

// removeAllRanges is suprisingly necessary for webkit ... BOOO!
				sel.removeAllRanges();
				sel.addRange( range );

} else if ( win.document.body.createTextRange ) { //IE's weirdness
				var range = document.body.createTextRange();

range.moveToElementText( el );
				range.collapse();
				range.moveStart( 'character', start );
				range.moveEnd( 'character', end !== undefined ? end : start );
				range.select();
			}
		}, /*
     * If one of the range values is within start and len, replace the range
     * value with the element and its offset.
     */
		replaceWithLess = function( start, len, range, el ) {
			if ( typeof range[0] === 'number' && range[0] < len ) {
				range[0] = {
					el: el, count: range[0] - start
				};
			}
			if ( typeof range[1] === 'number' && range[1] <= len ) {
				range[1] = {
					el: el, count: range[1] - start
				};
			}
		}, getCharElement = function( elems, range, len ) {
			var elem, start;

len = len || 0;

for ( var i = 0; elems[i]; i++ ) {
				elem = elems[i];
				// Get the text from text nodes and CDATA nodes
				if ( elem.nodeType === 3 || elem.nodeType === 4 ) {
					start = len;
					len += elem.nodeValue.length;
					//check if len is now greater than what's in counts
					replaceWithLess( start, len, range, elem );
					// Traverse everything else, except comment nodes
				} else if ( elem.nodeType !== 8 ) {
					len = getCharElement( elem.childNodes, range, len );
				}
			}

return len;
		};

$.fn.selection = function( start, end ) {
		if ( start !== undefined ) {
			return this.each( function() {
				select( this, start, end );
			} );
		} else {
			return getSelection( this[0] );
		}
	};

// for testing
	$.fn.selection.getCharElement = getCharElement;
})( jQuery );

Sid Gifari From Gifari Industries - BD Cyber Security Team