/*
 * Copyright (c) 2007-2008 Josh Bush (digitalbush.com)
 * 
 * Permission is hereby granted, free of charge, to any person
 * obtaining a copy of this software and associated documentation
 * files (the "Software"), to deal in the Software without
 * restriction, including without limitation the rights to use,
 * copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following
 * conditions:
 * The above copyright notice and this permission notice shall be
 * included in all copies or substantial portions of the Software.
 * 
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
 * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
 * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
 * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 * OTHER DEALINGS IN THE SOFTWARE. 
 */
 
/*
 * Version: 1.1.3
 * Release: 2008-04-16
 */ 
(function($) {

    //Helper Function for Caret positioning
    $.fn.caret=function(begin,end){
        if(this.length==0) return;
        if (typeof begin == 'number') {
            end = (typeof end == 'number')?end:begin;
            return this.each(function(){
                if(this.setSelectionRange){
                    this.focus();
                    this.setSelectionRange(begin,end);
                }else if (this.createTextRange){
                    var range = this.createTextRange();
                    range.collapse(true);
                    range.moveEnd('character', end);
                    range.moveStart('character', begin);
                    range.select();
                }
            });
        } else {
            if (this[0].setSelectionRange){
                begin = this[0].selectionStart;
                end = this[0].selectionEnd;
            }else if (document.selection && document.selection.createRange){
                var range = document.selection.createRange();
                begin = 0 - range.duplicate().moveStart('character', -100000);
                end = begin + range.text.length;
            }
            return {begin:begin,end:end};
        }
    };

    //Predefined character definitions
    var charMap={
        '9':"[0-9]",
        'a':"[A-Za-z]",
        '*':"[A-Za-z0-9]"
    };
    
    //Helper method to inject character definitions
    $.mask={
        addPlaceholder : function(c,r){
            charMap[c]=r;
        }
    };
    
    $.fn.unmask=function(){
        return this.trigger("unmask");
    };
    
    //Main Method
    $.fn.mask = function(mask,settings) {
        settings = $.extend({
            placeholder: "_",
            completed: null
        }, settings);
        
        //Build Regex for format validation
        var re = new RegExp("^"+
                $.map( mask.split(""), function(c,i){
            return charMap[c]||((/[A-Za-z0-9]/.test(c)?"":"\\")+c);
                }).join('')+
                        "$");

                        return this.each(function(){
                            var input=$(this);
                            var buffer=new Array(mask.length);
                            var locked=new Array(mask.length);
                            var valid=false;
                            var ignore=false;           //Variable for ignoring control keys
                            var firstNonMaskPos=null;
            
            //Build buffer layout from mask & determine the first non masked character          
                            $.each( mask.split(""), function(i,c){
                                locked[i]=(charMap[c]==null);
                                buffer[i]=locked[i]?c:settings.placeholder;
                                if(!locked[i] && firstNonMaskPos==null)
                                firstNonMaskPos=i;
                            });
            
                            function focusEvent(){
                                checkVal();
                                writeBuffer();
                                setTimeout(function(){
                                    $(input[0]).caret(valid?mask.length:firstNonMaskPos);
                                },0);
                            };
            
                            function keydownEvent(e){
                                var pos=$(this).caret();
                                var k = e.keyCode;
                                ignore=(k < 16 || (k > 16 && k < 32 ) || (k > 32 && k < 41));
                
                //delete selection before proceeding
                                if((pos.begin-pos.end)!=0 && (!ignore || k==8 || k==46)){
                                    clearBuffer(pos.begin,pos.end);
                                }
                //backspace and delete get special treatment
                                if(k==8){//backspace
                                    while(pos.begin-->=0){
                                        if(!locked[pos.begin]){
                                            buffer[pos.begin]=settings.placeholder;
                                            if($.browser.opera){
                                //Opera won't let you cancel the backspace, so we'll let it backspace over a dummy character.                               
                                                s=writeBuffer();
                                                input.val(s.substring(0,pos.begin)+" "+s.substring(pos.begin));
                                                $(this).caret(pos.begin+1);
                                            }else{
                                                writeBuffer();
                                                $(this).caret(Math.max(firstNonMaskPos,pos.begin));
                                            }
                                            return false;
                                        }
                                    }
                                }else if(k==46){//delete
                                    clearBuffer(pos.begin,pos.begin+1);
                                    writeBuffer();
                                    $(this).caret(Math.max(firstNonMaskPos,pos.begin));
                                    return false;
                                }else if (k==27){//escape
                                    clearBuffer(0,mask.length);
                                    writeBuffer();
                                    $(this).caret(firstNonMaskPos);
                                    return false;
                                }
                            };
            
                            function keypressEvent(e){
                                if(ignore){
                                    ignore=false;
                    //Fixes Mac FF bug on backspace
                                    return (e.keyCode == 8)? false: null;
                                }
                                e=e||window.event;
                                var k=e.charCode||e.keyCode||e.which;
                                var pos=$(this).caret();
                                
                                if(e.ctrlKey || e.altKey){//Ignore
                                    return true;
                                }else if ((k>=41 && k<=122) ||k==32 || k>186){//typeable characters
                                    var p=seekNext(pos.begin-1);
                                    if(p<mask.length){
                                        if(new RegExp(charMap[mask.charAt(p)]).test(String.fromCharCode(k))){
                                            buffer[p]=String.fromCharCode(k);
                                            writeBuffer();
                                            var next=seekNext(p);
                                            $(this).caret(next);
                                            if(settings.completed && next == mask.length)
                                            settings.completed.call(input);
                                        }
                                    }
                                }
                                return false;
                            };
            
                            function clearBuffer(start,end){
                                for(var i=start;i<end&&i<mask.length;i++){
                                    if(!locked[i])
                                    buffer[i]=settings.placeholder;
                                }
                            };
            
                            function writeBuffer(){
                                return input.val(buffer.join('')).val();
                            };
            
                            function checkVal(){
                //try to place charcters where they belong
                                var test=input.val();
                                var pos=0;
                                for(var i=0;i<mask.length;i++){
                                    if(!locked[i]){
                                        buffer[i]=settings.placeholder;
                                        while(pos++<test.length){
                            //Regex Test each char here.
                                            var reChar=new RegExp(charMap[mask.charAt(i)]);
                                            if(test.charAt(pos-1).match(reChar)){
                                                buffer[i]=test.charAt(pos-1);
                                                break;
                                            }
                                        }
                                    }
                                }
                                var s=writeBuffer();
                                if(!s.match(re)){
                                    input.val("");
                                    clearBuffer(0,mask.length);
                                    valid=false;
                                }else
                                    valid=true;
                            };
            
                            function seekNext(pos){
                                while(++pos<mask.length){
                                    if(!locked[pos])
                                    return pos;
                                }
                                return mask.length;
                            };
            
                            input.one("unmask",function(){
                                input.unbind("focus",focusEvent);
                                input.unbind("blur",checkVal);
                                input.unbind("keydown",keydownEvent);
                                input.unbind("keypress",keypressEvent);
                                if ($.browser.msie)
                                this.onpaste= null;
                                else if ($.browser.mozilla)
                                this.removeEventListener('input',checkVal,false);
                            });
                            input.bind("focus",focusEvent);
                            input.bind("blur",checkVal);
                            input.bind("keydown",keydownEvent);
                            input.bind("keypress",keypressEvent);
            //Paste events for IE and Mozilla thanks to Kristinn Sigmundsson
                            if ($.browser.msie)
                            this.onpaste= function(){setTimeout(checkVal,0);};
                            else if ($.browser.mozilla)
                            this.addEventListener('input',checkVal,false);
                
                            checkVal();//Perform initial check for existing values
                        });
    };
})(jQuery);