import base64
import binascii
from datetime import timedelta as td

from django import forms
from django.core.exceptions import ValidationError
from django.contrib.auth import authenticate
from django.contrib.auth.models import User
from hc.api.models import TokenBucket


class LowercaseEmailField(forms.EmailField):
    def clean(self, value):
        value = super(LowercaseEmailField, self).clean(value)
        return value.lower()


class Base64Field(forms.CharField):
    def to_python(self, value):
        if value is None:
            return None

        try:
            return base64.b64decode(value.encode())
        except binascii.Error:
            raise ValidationError(message="Cannot decode base64")


class AvailableEmailForm(forms.Form):
    # Call it "identity" instead of "email"
    # to avoid some of the dumber bots
    identity = LowercaseEmailField(
        error_messages={"required": "Please enter your email address."}
    )

    def clean_identity(self):
        v = self.cleaned_data["identity"]
        if len(v) > 254:
            raise forms.ValidationError("Address is too long.")

        if User.objects.filter(email=v).exists():
            raise forms.ValidationError(
                "An account with this email address already exists."
            )

        return v


class EmailLoginForm(forms.Form):
    # Call it "identity" instead of "email"
    # to avoid some of the dumber bots
    identity = LowercaseEmailField()

    def clean_identity(self):
        v = self.cleaned_data["identity"]
        if not TokenBucket.authorize_login_email(v):
            raise forms.ValidationError("Too many attempts, please try later.")

        try:
            self.user = User.objects.get(email=v)
        except User.DoesNotExist:
            raise forms.ValidationError("Incorrect email address.")

        return v


class PasswordLoginForm(forms.Form):
    email = LowercaseEmailField()
    password = forms.CharField()

    def clean(self):
        username = self.cleaned_data.get("email")
        password = self.cleaned_data.get("password")

        if username and password:
            if not TokenBucket.authorize_login_password(username):
                raise forms.ValidationError("Too many attempts, please try later.")

            self.user = authenticate(username=username, password=password)
            if self.user is None or not self.user.is_active:
                raise forms.ValidationError("Incorrect email or password.")

        return self.cleaned_data


class ReportSettingsForm(forms.Form):
    reports_allowed = forms.BooleanField(required=False)
    nag_period = forms.IntegerField(min_value=0, max_value=86400)

    def clean_nag_period(self):
        seconds = self.cleaned_data["nag_period"]

        if seconds not in (0, 3600, 86400):
            raise forms.ValidationError("Bad nag_period: %d" % seconds)

        return td(seconds=seconds)


class SetPasswordForm(forms.Form):
    password = forms.CharField(min_length=8)


class ChangeEmailForm(forms.Form):
    error_css_class = "has-error"
    email = LowercaseEmailField()

    def clean_email(self):
        v = self.cleaned_data["email"]
        if User.objects.filter(email=v).exists():
            raise forms.ValidationError("%s is already registered" % v)

        return v


class InviteTeamMemberForm(forms.Form):
    email = LowercaseEmailField(max_length=254)
    rw = forms.BooleanField(required=False)


class RemoveTeamMemberForm(forms.Form):
    email = LowercaseEmailField()


class ProjectNameForm(forms.Form):
    name = forms.CharField(max_length=60)


class TransferForm(forms.Form):
    email = LowercaseEmailField()


class AddCredentialForm(forms.Form):
    name = forms.CharField(max_length=100)
    client_data_json = Base64Field()
    attestation_object = Base64Field()


class WebAuthnForm(forms.Form):
    credential_id = Base64Field()
    client_data_json = Base64Field()
    authenticator_data = Base64Field()
    signature = Base64Field()
