Fix autofill name duplication

fixname.js

document.addEventListener("DOMContentLoaded", function() {
    const nameFirstInput = document.querySelector('input[name="name_first"]');
    const nameLastInput = document.querySelector('input[name="name_last"]');
  
    // Function to convert text to proper case
    function toProperCase(text) {
        return text
            .toLowerCase()
            .replace(/\b\w/g, function(char) { return char.toUpperCase(); });
    }

    // Function to update the name fields based on the specified conditions
    function updateNameFields() {
        let nameFirst = nameFirstInput.value.trim();
        let nameLast = nameLastInput.value.trim();
      
        // If name_first == name_last, check for spaces and split accordingly
        if (nameFirst === nameLast && nameFirst.includes(" ")) {
            const nameParts = nameFirst.split(" ");
            nameFirstInput.value = nameParts.slice(0, -1).join(" ");  // All but the last part
            nameLastInput.value = nameParts[nameParts.length - 1]; // The last part
        }

        // Convert both name_first and name_last to proper case if they are all uppercase
        if (nameFirst === nameFirst.toUpperCase()) {
            nameFirstInput.value = toProperCase(nameFirst);
        }
        if (nameLast === nameLast.toUpperCase()) {
            nameLastInput.value = toProperCase(nameLast);
        }

        // Handle case where name_first is in name_last (remove from name_last)
        const nameLastParts = nameLast.split(" ");
        const nameFirstWords = nameFirst.split(" ");

        nameLastInput.value = nameLastParts.filter(word => !nameFirstWords.includes(word)).join(" ");
        
        // Handle case where name_last is in name_first (remove from name_first)
        const nameFirstParts = nameFirst.split(" ");
        nameFirstInput.value = nameFirstParts.filter(word => !nameLastParts.includes(word)).join(" ");
    }

    // Listen for changes on both inputs
    nameFirstInput.addEventListener('input', updateNameFields);
    nameLastInput.addEventListener('input', updateNameFields);
});