how to register unique values? in the spreadsheet google app script web

i need a help to register only unique values inside the google spreadsheet behind the web script app

currently to save I use this script, practical find a way to block the launch if you already have values the same values in the spreadsheet.

basically there are two fields "cod" and "val"

if "cod" and "val" have already been registered before, it would need to show a message that these data are repeated.

I tried to do a check, but you can only do it in one "cod" field,

I would like to do it in both "cod" and "val" fields

https://docs.google.com/spreadsheets/d/1ZfIqw6_pkt1AdWsayyk1LdW_I6lU2yjsY1VfxfJneCA/edit#gid=0

function save_on_sheet(Data){

  var ss = SpreadsheetApp.openByUrl("https://docs.google.com/spreadsheets/d/1ZfIqw6_pkt1AdWsayyk1LdW_I6lU2yjsY1VfxfJneCA/edit#gid=0");
  var ws = ss.getSheetByName("page");

  const cod = ws.getRange(2, 1, ws.getLastRow()-1, 1).getValues().map(r => r[0].toString().toLowerCase());

  const posicaoIndex = cod.indexOf(Data.cod.toString().toLowerCase());

  if (posicaoIndex === -1) {

   ws.appendRow([
           Data.cod,
           Data.val
   ])

   return 'NEW';

  } else {

   return 'DUPLICATE';

  }

}

<!DOCTYPE html>
<html>
  <head>
    <base target="_top">
  </head>
  <body>
      <label for="cod">COD:</label>
      <input type="text" id="cod"><br><br>
      <label for="val">VALUE:</label>
      <input type="text" id="val"><br><br>
      <input type="submit" value="SAVE UNIQUE SHEET" onclick="save()">
  </body>

  <script>

   function save(){
     Data = {}
     Data.cod = document.getElementById("cod").value;
     Data.val = document.getElementById("val").value;

     google.script.run.withSuccessHandler(retorno).save_on_sheet(Data);

   }

     function retorno(mensagem_retorno){

      alert(mensagem_retorno);

  }

  </script>
</html>

Solution

You can refer to this sample code:

function save_on_sheet(Data){

  var ss = SpreadsheetApp.openByUrl("https://docs.google.com/spreadsheets/d/1ZfIqw6_pkt1AdWsayyk1LdW_I6lU2yjsY1VfxfJneCA/edit#gid=0");
  var ws = ss.getSheetByName("page");

  const dataVal = ws.getRange(2,1,ws.getLastRow()-1, 2).getDisplayValues();
  Logger.log(dataVal);

  for(var i=0; i<dataVal.length;i++){
    var rowData = dataVal[i];

    if(rowData[0]==Data.cod.toString().toLowerCase() && rowData[1]==Data.val.toString().toLowerCase()){
      //Exit function, duplicate found
      return 'DUPLICATE';
    }
  }

  //No duplicate found. Append new data
  ws.appendRow([
      Data.cod,
      Data.val
  ]);

  return 'NEW';

}

What it does?

Get cod and values data in the spreadsheet using Range.getDisplayValues() which will return a 2-d array of string values.
Loop each row value and compare cod and values to Data.cod and Data.values. If match found, return "DUPLICATE", if no match found, append the Data and return "NEW"