from django import forms
from exam.models import Profile

from django.contrib.auth import authenticate
from django.contrib.auth.models import User

from string import letters, punctuation

UNAME_CHARS = letters + "."
PWD_CHARS = letters + punctuation

class UserRegisterForm(forms.Form):

    username = forms.CharField(max_length=30)
    email = forms.EmailField()
    password = forms.CharField(max_length=30, widget=forms.PasswordInput())
    confirm_password = forms.CharField(max_length=30, widget=forms.PasswordInput())
    first_name = forms.CharField(max_length=30)
    last_name = forms.CharField(max_length=30)
    roll_number = forms.CharField(max_length=30)

    def clean_username(self):
        u_name = self.cleaned_data["username"]

        if u_name.strip(UNAME_CHARS):
            raise forms.ValidationError("Only letters and period character are \
                                         allowed in username")

        try:
            User.objects.get(username__iexact = u_name)
            raise forms.ValidationError("Username already exists")
        except User.DoesNotExist:
            return u_name

    def clean_password(self):
        pwd = self.cleaned_data['password']
        if pwd.strip(PWD_CHARS):
            raise forms.ValidationError("Only letters and punctuation are \
                                         allowed in password")
        return pwd

    def clean_confirm_password(self):
        c_pwd = self.cleaned_data['confirm_password']
        pwd = self.data['password']
        if c_pwd != pwd:
            raise forms.ValidationError("Passwords do not match")

        return c_pwd

    def save(self):
        u_name = self.cleaned_data["username"]
        u_name = u_name.lower()
        pwd = self.cleaned_data["password"]
        email = self.cleaned_data['email']
        new_user = User.objects.create_user(u_name, email, pwd)

        new_user.first_name = self.cleaned_data["first_name"]
        new_user.last_name = self.cleaned_data["last_name"]
        new_user.save()

        new_profile = Profile(user=new_user)
        new_profile.roll_number = self.cleaned_data["roll_number"]
        new_profile.save()

        return u_name, pwd

class UserLoginForm(forms.Form):
    username = forms.CharField(max_length = 30)
    password = forms.CharField(max_length=30, widget=forms.PasswordInput())

    def clean(self):
        super(UserLoginForm, self).clean()
        u_name, pwd = self.cleaned_data["username"], self.cleaned_data["password"]
        user = authenticate(username = u_name, password = pwd)

        if not user:
            raise forms.ValidationError("Invalid username/password")

        return user