Could someone Please help with 24 hr time

this time will convert “8pm” or “8 pm” or “8:00pm” or “8:00 pm” or “8p” or “8 p” or “8:00p” or “8:00 p” or "8" or "815" to military time.
The problem I'm having is if you enter 1AM it will change it to 1:00 not 01:00. Could someone please help? I know it's messy and ugly code, but really pulling out my hair at this point
 
form1.Page1.ShiftStartTime::change - (JavaScript, client)
if (xfa.event.change.match(/[0-9\p\P\a\A\m\M\:]/) == null)
xfa.event.change = "";
-------------------------------------------------------------------
Display Pattern
time{HH:MM}
 
Edit Pattern
time{hh:MMA}|time{h:MMA}|time{hh:MM A}|time{h:MM A}|time{hh:MA}|time{h:MA}|time{hh:M A}|time{h:M A}|time{hh:MMA}|time{h:MMA}|time{hh:MM A}|time{h:MM A}|time{hh:MA}|time{h:MA}|time{hh:M A}|time{h:M A}|time{HH:MM}|time{H:MM}|time{H:M}|time{HH:M}|time{hh:MM}|time{h:MM}|time{hh:MM}|time{h:M}|time{h:M}
-------------------------------------------------------------------
form1.Page1.ShiftStartTime::exit - (JavaScript, client)
if (!(this.isNull)) {
var fldValue = this.formattedValue;
var dayIndicator
var str = fldValue;
//add the "m" if the user only enters p like 8p
if (str.search = "P" && str.indexOf("M") == -1 && str.indexOf("m") == -1){
dayIndicator = str + "m";
fldValue = dayIndicator
}
//add the "m" if the user only enters a like 8a
if (str.search = "A" && str.indexOf("M") == -1 && str.indexOf("m") == -1){
dayIndicator = str + "m";
fldValue = dayIndicator
}
//get the am/pm indicator and make it upper case
dayIndicator = fldValue.substr(fldValue.length - 2)
dayIndicator = dayIndicator.toUpperCase();
//this.formattedValue = fldValue
 
//get the Hours + Mins - set them where neccessary
var hrs
var mins
var regExpression = / /g
var temp = fldValue.substr(0, fldValue.length - 2)
if (temp.length <= 3){
hrs = temp;
hrs = hrs.replace(regExpression, "");
}
var lastColon = fldValue.indexOf(":");
if (lastColon == -1){
mins = ""
} else {
mins = fldValue.substr(lastColon + 1, 2)
hrs = fldValue.substr(0,lastColon)
}
 
//write the military time out also in 24 hour
//starting is 00:00 and not 24:00
//only when finishing is it 24:00
if ((dayIndicator == "PM")&&(hrs ==12)){
hrs = "00"
}
//starting is 00:00 and not 24:00
if ((dayIndicator == "AM")&&(hrs ==12)){
hrs = "00"
}
if (dayIndicator == "PM"){
hrs = parseInt(hrs) + 12
}
if (mins == ""){
mins = "00"
}
//For when users enter 8 it will add a zero to the front
//so the time box changes it to 08:00
if (hrs == "" && temp.length <= 2 && str.indexOf(":") == -1 && str.indexOf("A") == -1 && str.indexOf("a") == -1){
hrs = "0" + this.formattedValue;
hrs = hrs.replace(regExpression, "");
this.rawvalue = parseInt(hrs)
}
//For when users enter 815 it will add a zero to the front
//so the time box changes it to 08:15
if (this.formattedValue.length == 3 && str.indexOf(":") == -1 && str.indexOf("A") == -1 && str.indexOf("a") == -1 && str.indexOf("P") == -1 && str.indexOf("p") == -1){
hrs = "0" + this.formattedValue;
hrs = hrs.substr(0,2);
mins = str.substr(1,4);
}
this.formattedValue = hrs + ":" + mins
}