from django import forms
from .models import FriendCode

class FriendCodeForm(forms.ModelForm):
    class Meta:
        model = FriendCode
        fields = ["friend_code"]

    def clean_friend_code(self):
        friend_code = self.cleaned_data.get("friend_code", "").strip()
        
        # Remove any dashes from the input so we can validate the digits only.
        friend_code_clean = friend_code.replace("-", "")
        
        # Ensure that the cleaned friend code is exactly 16 digits.
        if len(friend_code_clean) != 16 or not friend_code_clean.isdigit():
            raise forms.ValidationError("Friend code must be exactly 16 digits long.")
        
        # Format the friend code with dashes: XXXX-XXXX-XXXX-XXXX.
        friend_code_formatted = f"{friend_code_clean[:4]}-{friend_code_clean[4:8]}-{friend_code_clean[8:12]}-{friend_code_clean[12:16]}"
        
        return friend_code_formatted