How to get a range from cell parameters without using strings in a custom function?

Question

I'm new to google sheet script and I'm trying to make a function that outputs the max value of possible opions from a DropDown list.

The feature of the function work but only when I call the following function in a cell

=MAXDROPDOWN(CELL("address";C13))

and it outputs an Error when doing

=MAXDROPDOWN(C13)

Where C13 is a dropdown list

I'm sure there is a better way to do this but I'm really unable to I tried a lot of options but it never works.

=MAXDROPDOWN("C13") works but it disables all smart features associated with functions and cell reference since its a string provided so it loses its advantage of using it over my proposition above with =MAXDROPDOWN(CELL("address";C13))

I tried with getA1notation before to but I only saw it functioning on current active cells the function is called from and not on cells as parameters to the function

Thanks in advance for your help

function MAXDROPDOWN(cell1){
try {
var cell = SpreadsheetApp.getActive().getRange(cell1);
var rule = cell.getDataValidation();
if (rule != null) {
  var args = rule.getCriteriaValues();
  return Math.max(...args[0])
} 
}
catch( err ) {
  return "#ERROR!" 
}
}

Thank to TheWizEd I was able to do what I wanted. Below is what I did.

function MAXDROPDOWN(cell){
try {
var cell1 = SpreadsheetApp.getActive().getRange(CELL_ADDRESS(cell));
var rule = cell1.getDataValidation();
if (rule != null) {
  var args = rule.getCriteriaValues();
  return Math.max(...args[0])
} 
}
catch( err ) {
  return "#ERROR!" 
}
}

function CELL_ADDRESS(cell) {
  let test = SpreadsheetApp.getActiveSheet().getActiveCell().getFormula();
  let address = test.match(/\(.+\)/)[0];
  return(address.slice(1,-1));
}

Answer 1

Note that =MAXDROPDOWN(C13) will pass the value of cell C13, not the address. If you want the address you can parse the formula as shown in this example.

If I place this formula in any cell as =MAXDROPDOWN(A1) it will give me as address the string "A1"

function MAXDROPDOWN(cell) {
  let test = SpreadsheetApp.getActiveSheet().getActiveCell().getFormula();
  let address = test.match(/\(.+\)/)[0];
  console.log(address.slice(1,-1));
}