My function runs but only does part of it on the second try

Question

Here's my code. It is a draft of a German Enigma machine. I'm trying to make the message that I will actually run through the machine except that it doesn't create that message until I run the function the second time. The weird thing is that I know the function runs because I see parts of it execute, but as far as the code is concerned toWorkWith is empty on the first run and filled on the second?

 

function encode(){
        var alphabet = ["A","B","C","D","E","F","G","H","I","J","K","L","M","N","O","P","Q","R","S","T","U","V","W","X","Y","Z"]
        var rotor_1 = {"A":["E"],"B":["K"],"C":["M"],"D":["F"],"E":["L"],"F":["G"],"G":["D"],"H":["Q"],"I":["V"],"J":["Z"],"K":["N"],"L":["T"],"M":["O"],"N":["W"],"O":["Y"],"P":["H"],"Q":["X"],"R":["U"],"S":["S"],"T":["P"],"U":["A"],"V":["I"],"W":["B"],"X":["R"],"Y":["C"],"Z":["J"]};
        var rotor_2 = {"A":["A"],"B":["J"],"C":["D"],"D":["K"],"E":["S"],"F":["I"],"G":["R"],"H":["U"],"I":["X"],"J":["B"],"K":["L"],"L":["H"],"M":["W"],"N":["T"],"O":["M"],"P":["C"],"Q":["Q"],"R":["G"],"S":["Z"],"T":["N"],"U":["P"],"V":["Y"],"W":["F"],"X":["V"],"Y":["O"],"Z":["E"]};
        var rotor_3 = {"A":["B"],"B":["D"],"C":["F"],"D":["H"],"E":["J"],"F":["L"],"G":["C"],"H":["P"],"I":["R"],"J":["T"],"K":["X"],"L":["V"],"M":["Z"],"N":["N"],"O":["Y"],"P":["E"],"Q":["I"],"R":["W"],"S":["G"],"T":["A"],"U":["K"],"V":["M"],"W":["U"],"X":["S"],"Y":["Q"],"Z":["O"]};
        var reflector = {"A":["A"],"B":["B"],"C":["C"],"D":["D"],"E":["E"],"F":["F"],"G":["G"],"H":["H"],"I":["I"],"J":["J"],"K":["K"],"L":["L"],"M":["M"],"N":["N"],"O":["O"],"P":["P"],"Q":["Q"],"R":["R"],"S":["S"],"T":["T"],"U":["U"],"V":["V"],"W":["W"],"X":["X"],"Y":["Y"],"Z":["Z"]};
        document.simulator.encoder.value.toUpperCase();
        var message = document.simulator.encoder.value.trim();
        message.toUpperCase();
        document.simulator.encoder.value = message.toUpperCase();
        var code = []
        //Turns the rotors
        function updateRotorState(rotorNum){
                var rotor1state = document.simulator.rotor1.value.toUpperCase();
                var rotor2state = document.simulator.rotor2.value.toUpperCase();
                var rotor3state = document.simulator.rotor3.value.toUpperCase();
                if(rotorNum == 1){
                        var rotorPos = alphabet.indexOf(rotor1state);
                       
                        var newPos = rotorPos + 1;
                       
                        if(rotor1state == "V"){
                                document.simulator.rotor1.value=alphabet[newPos]
                                updateRotorState(2);
                        }
                        if(rotorPos == 25){
                                newPos = 0;
                        }
                        document.simulator.rotor1.value = alphabet[newPos];
                }
                if(rotorNum == 2){
                        var rotorPos = alphabet.indexOf(rotor2state);
                        var newPos = rotorPos + 1;
                        if(rotor2state == "E"){
                                document.simulator.rotor2.value = alphabet[newPos];
                                updateRotorState(3);
                        }
                        if(rotorPos == 25){
                                newPos = 0;    
                        }
                        document.simulator.rotor2.value = alphabet[newPos];
                }
                if(rotorNum == 3){
                        var rotorPos = alphabet.indexOf(rotor3state);
                        var newPos = rotorPos + 1;
                        if(rotorPos == 25){
                                newPos = 0;    
                        }
                        document.simulator.rotor3.value = alphabet[newPos]
                        //Eventually need to add code to make next rotor turn over
                }
        }
        //Turns the message into a stripped output. Removes all non letter characters including spaces
        function workingMessageGen(message){
                var workingMessage = ""
                var messageArray = message.split('');
                for(var char in messageArray){
                        for(var letter in alphabet){
                                if(messageArray[char] == alphabet[letter]){
                                        workingMessage += alphabet[letter];
                                }
                        }
                }
                return workingMessage;
        }
        toWorkWith = workingMessageGen(message);
        for(var letter in message){
                updateRotorState(1);
        }
        document.simulator.decoder.value=toWorkWith;
}

Answer 1

I'm not sure what you expect to happen, but there are some flaws in the code:

• JavaScript string values are immutable - they are no objects. Calling functions like toUpperCase will not change the variables, but return the new value. document.simulator.encoder.value.toUpperCase() and message.toUpperCase() are useless therefore.
• Missing semicolon after var code = [] (though it should not matter, you can never be sure)
• toWorkWith is missing a var declaration - seems not to be intended
• for(var char in messageArray) - never enumerate array properties! Use a for loop to iterate its indizes (see Why is using "for...in" with array iteration a bad idea?)
• for(var letter in message) - since message is a string, do not try to enumerate its properties! a) does this not work in IE b) you might catch enumerable properties on String.prototype. Instead, use a normal for loop and message.length.
• All over your script, you are mixing code logic and DOM accessing. Do you use the DOM to retrieve, show, store values? Do it in 3 steps: read input from DOM, execute logic, write output.