from django import forms
from django.contrib import admin
from django.contrib.auth.admin import UserAdmin
from django.contrib.auth.forms import ReadOnlyPasswordHashField
from django.contrib.auth.models import Group

from .models import MyUser

__all__ = (
    "UserCreationForm",
    "UserChangeForm",
    "MyUserAdmin",
)


class UserCreationForm(forms.ModelForm):
    """A form for creating new users.

    Includes all the required fields, plus a repeated password.
    """

    password1 = forms.CharField(label="Password", widget=forms.PasswordInput)
    password2 = forms.CharField(
        label="Password confirmation", widget=forms.PasswordInput
    )

    class Meta:
        """Meta."""

        model = MyUser
        fields = (
            "username",
            "email",
            "first_name",
            "last_name",
            "date_of_birth",
        )

    def clean_password2(self):
        # Check that the two password entries match
        password1 = self.cleaned_data.get("password1")
        password2 = self.cleaned_data.get("password2")
        if password1 and password2 and password1 != password2:
            raise forms.ValidationError("Passwords don't match")
        return password2

    def save(self, commit=True):
        # Save the provided password in hashed format
        user = super(UserCreationForm, self).save(commit=False)
        user.set_password(self.cleaned_data["password1"])
        if commit:
            user.save()
        return user


class UserChangeForm(forms.ModelForm):
    """A form for updating users.

    Includes all the fields on the user, but replaces the password field
    with admin's password hash display field.
    """

    password = ReadOnlyPasswordHashField()

    class Meta:
        """Meta."""

        model = MyUser
        fields = (
            "username",
            "email",
            "first_name",
            "last_name",
            "password",
            "date_of_birth",
            "is_active",
        )

    def clean_password(self):
        # Regardless of what the user provides, return the initial value.
        # This is done here, rather than on the field, because the
        # field does not have access to the initial value
        return self.initial["password"]


class MyUserAdmin(UserAdmin):
    """MyUser admin."""

    # The forms to add and change user instances
    form = UserChangeForm
    add_form = UserCreationForm

    # The fields to be used in displaying the User model.
    # These override the definitions on the base UserAdmin
    # that reference specific fields on auth.User.
    list_display = (
        "username",
        "email",
        "first_name",
        "last_name",
        "date_of_birth",
    )
    fieldsets = (
        (None, {"fields": ("username", "email", "password")}),
        (
            "Personal info",
            {
                "fields": (
                    "first_name",
                    "last_name",
                    "date_of_birth",
                )
            },
        ),
        (
            "Permissions",
            {
                "fields": (
                    "is_active",
                    "is_staff",
                    "is_superuser",
                    "groups",
                    "user_permissions",
                )
            },
        ),
    )
    # add_fieldsets is not a standard ModelAdmin attribute. UserAdmin
    # overrides get_fieldsets to use this attribute when creating a user.
    add_fieldsets = (
        (
            None,
            {
                "classes": ("wide",),
                "fields": (
                    "username",
                    "email",
                    "first_name",
                    "last_name",
                    "date_of_birth",
                    "password1",
                    "password2",
                ),
            },
        ),
    )
    search_fields = ("email",)
    ordering = ("email",)
    filter_horizontal = []


# Now register the new UserAdmin...
admin.site.register(MyUser, MyUserAdmin)

# ...and, since we're not using Django's built-in permissions,
# un-register the Group model from admin.
admin.site.unregister(Group)