// ===================================================================
// Author: Matt Kruse <matt@mattkruse.com>
// WWW: http://www.mattkruse.com/
//
// NOTICE: You may use this code for any purpose, commercial or
// private, without any further permission from the author. You may
// remove this notice from your final code if you wish, however it is
// appreciated by the author if at least my web site address is kept.
//
// You may *NOT* re-distribute this code in any way except through its
// use. That means, you can include it in your product, or your web
// site, or any other form where the code is actually being used. You
// may not put the plain javascript up on your site for download or
// include it in your javascript libraries for download. 
// If you wish to share this code with others, please just point them
// to the URL instead.
// Please DO NOT link directly to my .js files from your site. Copy
// the files to your server and use them there. Thank you.
// ===================================================================

var MONTH_NAMES=new Array('January','February','March','April','May','June','July','August','September','October','November','December','Jan','Feb','Mar','Apr','May','Jun','Jul','Aug','Sep','Oct','Nov','Dec');
var DAY_NAMES=new Array('Sunday','Monday','Tuesday','Wednesday','Thursday','Friday','Saturday','Sun','Mon','Tue','Wed','Thu','Fri','Sat');

function LZ(x){
  return(x<0||x>9?"":"0")+x
}

function isDate(val,format){
        var date=getDateFromFormat(val,format);
        if(date==0){
                return false;
        }
        return true;
}

function compareDates(date1,dateformat1,date2,dateformat2){
        var d1=getDateFromFormat(date1,dateformat1);
        var d2=getDateFromFormat(date2,dateformat2);
        if(d1==0 || d2==0){
                return -1;
        }
        else if(d1 > d2){
                return 1;
        }
        return 0;
}

function formatDate(date,format){
        format=format+"";
        var result="";
        var i_format=0;
        var c="";
        var token="";
        var y=date.getYear()+"";
        var M=date.getMonth()+1;
        var d=date.getDate();
        var E=date.getDay();
        var H=date.getHours();
        var m=date.getMinutes();
        var s=date.getSeconds();
        var yyyy,yy,MMM,MM,dd,hh,h,mm,ss,ampm,HH,H,KK,K,kk,k;
        var value=new Object();

        if(y.length < 4){
                y=""+(y-0+1900);
        }
        value["y"]=""+y;
        value["yyyy"]=y;
        value["yy"]=y.substring(2,4);
        value["M"]=M;
        value["MM"]=LZ(M);
        value["MMM"]=MONTH_NAMES[M-1];
        value["NNN"]=MONTH_NAMES[M+11];
        value["d"]=d;
        value["dd"]=LZ(d);
        value["E"]=DAY_NAMES[E+7];
        value["EE"]=DAY_NAMES[E];
        value["H"]=H;
        value["HH"]=LZ(H);
        if(H==0){
                value["h"]=12;
        }
        else if(H>12){
                value["h"]=H-12;
        }
        else{
                value["h"]=H;
        }
        value["hh"]=LZ(value["h"]);

        if(H>11){
                value["K"]=H-12;
        }
        else{
                value["K"]=H;
        }
        value["k"]=H+1;
        value["KK"]=LZ(value["K"]);
        value["kk"]=LZ(value["k"]);
        if(H > 11){
                value["a"]="PM";
        }
        else{
                value["a"]="AM";
        }
        value["m"]=m;
        value["mm"]=LZ(m);
        value["s"]=s;
        value["ss"]=LZ(s);
        while(i_format < format.length){
                c=format.charAt(i_format);
                token="";
                while((format.charAt(i_format)==c) &&(i_format < format.length)){
                        token += format.charAt(i_format++);
                }
                if(value[token] != null){
                        result=result + value[token];
                }
                else{
                        result=result + token;
                }
        }
        return result;
}

function _isInteger(val){
        var digits="1234567890";
        for(var i=0; i < val.length; i++){
                if(digits.indexOf(val.charAt(i))==-1){
                        return false;
                }
        }
        return true;
}

function _getInt(str,i,minlength,maxlength){
        for(var x=maxlength; x>=minlength; x--){
                var token=str.substring(i,i+x);
                if(token.length < minlength){
                        return null;
                }
                if(_isInteger(token)){
                        return token;
                }
        }
        return null;
}

function getDateFromFormat(val,format){
        val=val+"";
        format=format+"";
        var i_val=0;
        var i_format=0;
        var c="";
        var token="";
        var token2="";
        var x,y;
        var now=new Date();
        var year=now.getYear();
        var month=now.getMonth()+1;
        var date=1;
        var hh=now.getHours();
        var mm=now.getMinutes();
        var ss=now.getSeconds();
        var ampm="";
        while(i_format < format.length){
                c=format.charAt(i_format);
                token="";
                while((format.charAt(i_format)==c) &&(i_format < format.length)){
                        token += format.charAt(i_format++);
                }
                if(token=="yyyy" || token=="yy" || token=="y"){
                        if(token=="yyyy"){
                                x=4;
                                y=4;
                        }
                        if(token=="yy"){
                                x=2;
                                y=2;
                        }
                        if(token=="y"){
                                x=2;
                                y=4;
                        }
                        year=_getInt(val,i_val,x,y);
                        if(year==null){
                                return 0;
                        }
                        i_val += year.length;
                        if(year.length==2){
                                if(year > 70){
                                        year=1900+(year-0);
                                }
                                else{
                                        year=2000+(year-0);
                                }
                        }
                }
                else if(token=="MMM"||token=="NNN"){
                        month=0;
                        for(var i=0; i<MONTH_NAMES.length; i++){
                                var month_name=MONTH_NAMES[i];
                                if(val.substring(i_val,i_val+month_name.length).toLowerCase()==month_name.toLowerCase()){
                                        if(token=="MMM"||(token=="NNN"&&i>11)){
                                                month=i+1;
                                                if(month>12){
                                                        month -= 12;
                                                }
                                                i_val += month_name.length;
                                                break;
                                        }
                                }
                        }
                        if((month < 1)||(month>12)){
                                return 0;
                        }
                }
                else if(token=="EE"||token=="E"){
                        for(var i=0; i<DAY_NAMES.length; i++){
                                var day_name=DAY_NAMES[i];
                                if(val.substring(i_val,i_val+day_name.length).toLowerCase()==day_name.toLowerCase()){
                                        i_val += day_name.length;
                                        break;
                                }
                        }
                }
                else if(token=="MM"||token=="M"){
                        month=_getInt(val,i_val,token.length,2);
                        if(month==null||(month<1)||(month>12)){
                                return 0;
                        }
                        i_val+=month.length;
                }
                else if(token=="dd"||token=="d"){
                        date=_getInt(val,i_val,token.length,2);
                        if(date==null||(date<1)||(date>31)){
                                return 0;
                        }
                        i_val+=date.length;
                }
                else if(token=="hh"||token=="h"){
                        hh=_getInt(val,i_val,token.length,2);
                        if(hh==null||(hh<1)||(hh>12)){
                                return 0;
                        }
                        i_val+=hh.length;
                }
                else if(token=="HH"||token=="H"){
                        hh=_getInt(val,i_val,token.length,2);
                        if(hh==null||(hh<0)||(hh>23)){
                                return 0;
                        }
                        i_val+=hh.length;
                }
                else if(token=="KK"||token=="K"){
                        hh=_getInt(val,i_val,token.length,2);
                        if(hh==null||(hh<0)||(hh>11)){
                                return 0;
                        }
                        i_val+=hh.length;
                }
                else if(token=="kk"||token=="k"){
                        hh=_getInt(val,i_val,token.length,2);
                        if(hh==null||(hh<1)||(hh>24)){
                                return 0;
                        }
                        i_val+=hh.length;
                        hh--;
                }
                else if(token=="mm"||token=="m"){
                        mm=_getInt(val,i_val,token.length,2);
                        if(mm==null||(mm<0)||(mm>59)){
                                return 0;
                        }
                        i_val+=mm.length;
                }
                else if(token=="ss"||token=="s"){
                        ss=_getInt(val,i_val,token.length,2);
                        if(ss==null||(ss<0)||(ss>59)){
                                return 0;
                        }
                        i_val+=ss.length;
                }
                else if(token=="a"){
                        if(val.substring(i_val,i_val+2).toLowerCase()=="am"){
                                ampm="AM";
                        }
                        else if(val.substring(i_val,i_val+2).toLowerCase()=="pm"){
                                ampm="PM";
                        }
                        else{
                                return 0;
                        }
                        i_val+=2;
                }
                else{
                        if(val.substring(i_val,i_val+token.length)!=token){
                                return 0;
                        }
                        else{
                                i_val+=token.length;
                        }
                }
        }
        if(i_val != val.length){
                return 0;
        }
        if(month==2){
                if( ((year%4==0)&&(year%100 != 0) ) ||(year%400==0) ){
                        if(date > 29){
                                return 0;
                        }
                }
                else{
                        if(date > 28){
                                return 0;
                        }
                }
        }
        if((month==4)||(month==6)||(month==9)||(month==11)){
                if(date > 30){
                        return 0;
                }
        }
        if(hh<12 && ampm=="PM"){
                hh=hh-0+12;
        }
        else if(hh>11 && ampm=="AM"){
                hh-=12;
        }
        var newdate=new Date(year,month-1,date,hh,mm,ss);
        return newdate.getTime();
}

function parseDate(val){
        var preferEuro=(arguments.length==2)?arguments[1]:false;
        generalFormats=new Array('y-M-d','MMM d, y','MMM d,y','y-MMM-d','d-MMM-y','MMM d');
        monthFirst=new Array('M/d/y','M-d-y','M.d.y','MMM-d','M/d','M-d');
        dateFirst =new Array('d/M/y','d-M-y','d.M.y','d-MMM','d/M','d-M');
        var checkList=new Array('generalFormats',preferEuro?'dateFirst':'monthFirst',preferEuro?'monthFirst':'dateFirst');
        var d=null;
        for(var i=0; i<checkList.length; i++){
                var l=window[checkList[i]];
                for(var j=0; j<l.length; j++){
                        d=getDateFromFormat(val,l[j]);
                        if(d!=0){
                                return new Date(d);
                        }
                }
        }
        return null;
}