"""
This module defines form classes for mailbox and mail address editing.

"""
from __future__ import absolute_import, unicode_literals

from django import forms
from django.core.urlresolvers import reverse
from django.core.validators import validate_email
from django.utils.translation import ugettext_lazy as _

from crispy_forms.helper import FormHelper
from crispy_forms.bootstrap import AppendedText
from crispy_forms.layout import (
    Div,
    Layout,
    Submit,
)

from .models import (
    MailAddress,
    Mailbox,
)
from gvawebcore.forms import PasswordModelFormMixin

from model_utils import Choices

MAILBOX_OR_FORWARDS = Choices(
    (0, 'mailbox', _('Mailbox')),
    (1, 'forwards', _('Forwards')),
)


class CreateMailboxForm(PasswordModelFormMixin, forms.ModelForm):
    """
    This form is used to create new Mailbox instances.

    """
    class Meta:
        model = Mailbox
        fields = []

    def __init__(self, *args, **kwargs):
        self.hosting_package = kwargs.pop('hostingpackage')
        super(CreateMailboxForm, self).__init__(*args, **kwargs)
        self.helper = FormHelper()
        self.helper.form_action = reverse(
            'create_mailbox', kwargs={'package': self.hosting_package.id})
        self.helper.add_input(Submit('submit', _('Create mailbox')))

    def save(self, commit=True):
        """
        Set the new mailbox's password and osuser.

        :param boolean commit: whether to save the created mailbox
        :return: mailbox instance
        :rtype: :py:class:`managemails.models.Mailbox`

        """
        osuser = self.hosting_package.osuser
        self.instance.osuser = osuser
        self.instance.username = Mailbox.objects.get_next_mailbox_name(osuser)
        self.instance.set_password(self.cleaned_data['password1'])
        return super(CreateMailboxForm, self).save(commit=commit)


class ChangeMailboxPasswordForm(PasswordModelFormMixin, forms.ModelForm):
    """
    This form is used to set a new password for an existing mailbox.

    """
    class Meta:
        model = Mailbox
        fields = []

    def __init__(self, *args, **kwargs):
        self.hosting_package = kwargs.pop('hostingpackage')
        super(ChangeMailboxPasswordForm, self).__init__(*args, **kwargs)
        self.helper = FormHelper()
        self.helper.form_action = reverse(
            'change_mailbox_password', kwargs={
                'package': self.hosting_package.id,
                'slug': self.instance.username,
            })
        self.helper.add_input(Submit('submit', _('Set password')))

    def save(self, commit=True):
        """
        Set the mailbox password.

        :param boolean commit: whether to save the mailbox instance
        :return: mailbox instance
        :rtype: :py:class:`managemails.models.Mailbox`

        """
        self.instance.set_password(self.cleaned_data['password1'])
        return super(ChangeMailboxPasswordForm, self).save(commit=commit)


def multiple_email_validator(value):
    if value:
        for email in [part.strip() for part in value.split(',')]:
            validate_email(email)
    return value


class MailAddressFieldMixin(forms.Form):
    """
    This mixin defines form fields common to mail address forms.

    """
    mailbox_or_forwards = forms.TypedChoiceField(
        label=_('Mailbox or Forwards'),
        choices=MAILBOX_OR_FORWARDS,
        widget=forms.RadioSelect,
        coerce=int,
    )
    mailbox = forms.ModelChoiceField(
        Mailbox.objects,
        label=_('Mailbox'),
        required=False,
    )
    forwards = forms.CharField(
        label=_('Forwards'),
        required=False,
        error_messages={
            'invalid': _(
                'Please enter one or more email addresses separated by '
                'commas.'),
        },
        validators=[multiple_email_validator],
    )


class AddMailAddressForm(forms.ModelForm, MailAddressFieldMixin):
    """
    This form is used to add a new mail address.

    """
    class Meta:
        model = MailAddress
        fields = ['localpart']

    def __init__(self, *args, **kwargs):
        self.maildomain = kwargs.pop('maildomain')
        self.hosting_package = kwargs.pop('hostingpackage')
        super(AddMailAddressForm, self).__init__(*args, **kwargs)
        self.fields['mailbox'].queryset = Mailbox.objects.unused(
            osuser=self.hosting_package.osuser,
        )

        self.helper = FormHelper()
        self.helper.form_action = reverse(
            'add_mailaddress', kwargs={
                'package': self.hosting_package.id,
                'domain': self.maildomain.domain,
            })
        self.helper.layout = Layout(
            Div(
                Div(
                    AppendedText('localpart', '@' + self.maildomain.domain),
                    css_class='col-lg-4 col-md-4 col-xs-12',
                ),
                Div(
                    'mailbox_or_forwards',
                    css_class='col-lg-2 col-md-2 col-xs-12',
                ),
                Div(
                    'mailbox',
                    'forwards',
                    css_class='col-lg-6 col-md-6 col-xs-12',
                ),
                css_class='row',
            ),
            Submit('submit', _('Add mail address')),
        )

    def clean_localpart(self):
        localpart = self.cleaned_data['localpart']
        if MailAddress.objects.filter(
            domain=self.maildomain,
            localpart=localpart,
        ).exists():
            raise forms.ValidationError(
                _('This mail address is already in use.'))
        validate_email('{0}@{1}'.format(localpart, self.maildomain.domain))
        return localpart

    def clean(self):
        data = self.cleaned_data
        if data['mailbox_or_forwards'] == MAILBOX_OR_FORWARDS.mailbox:
            if not data['mailbox']:
                self.add_error('mailbox', _('No mailbox selected'))
        elif data['mailbox_or_forwards'] == MAILBOX_OR_FORWARDS.forwards:
            if 'forwards' not in data or not data['forwards']:
                self.add_error('forwards', _('No forward addresses selected'))
        else:
            raise forms.ValidationError(
                _('Illegal choice for target of the mail address'))

    def save(self, commit=True):
        """
        Save the mail address.

        :param boolean commit: whether to save the mail address instance
        :return: mail address instance
        :rtype: :py:class:`managemails.models.MailAddress`

        """
        self.instance.domain = self.maildomain
        data = self.cleaned_data
        target_choice = data['mailbox_or_forwards']
        if target_choice == MAILBOX_OR_FORWARDS.mailbox:
            mabox = self.instance.set_mailbox(data['mailbox'], commit=False)
        elif target_choice == MAILBOX_OR_FORWARDS.forwards:
            targets = [part.strip() for part in data['forwards'].split()]
            fwds = self.instance.set_forward_addresses(targets, commit=False)
        mailaddress = super(AddMailAddressForm, self).save(commit)
        if commit:
            if target_choice == MAILBOX_OR_FORWARDS.mailbox:
                mabox.mailaddress = mailaddress
                mabox.save()
            elif target_choice == MAILBOX_OR_FORWARDS.forwards:
                for fwd in fwds:
                    fwd.mailaddress = mailaddress
                    fwd.save()
        return mailaddress


class EditMailAddressForm(forms.ModelForm, MailAddressFieldMixin):
    """
    This form is used to edit the targets for a mail address.

    """
    class Meta:
        model = MailAddress
        fields = []

    def __init__(self, *args, **kwargs):
        self.hosting_package = kwargs.pop('hostingpackage')
        self.maildomain = kwargs.pop('maildomain')
        super(EditMailAddressForm, self).__init__(*args, **kwargs)
        self.fields['mailbox'].queryset = Mailbox.objects.unused_or_own(
            self.instance, self.hosting_package.osuser
        )

        self.helper = FormHelper()
        self.helper.form_action = reverse(
            'edit_mailaddress', kwargs={
                'package': self.hosting_package.id,
                'domain': self.maildomain.domain,
                'pk': self.instance.id,
            })
        self.helper.layout = Layout(
            Div(
                Div(
                    'mailbox_or_forwards',
                    css_class='col-log-2 col-md-2 col-xs-12',
                ),
                Div(
                    'mailbox',
                    'forwards',
                    css_class='col-lg-10 col-md-10 col-xs-12',
                ),
                css_class='row',
            ),
            Submit('submit', _('Change mail address targets')),
        )

    def clean(self):
        data = self.cleaned_data
        if data['mailbox_or_forwards'] == MAILBOX_OR_FORWARDS.mailbox:
            if not data['mailbox']:
                self.add_error('mailbox', _('No mailbox selected'))
        elif data['mailbox_or_forwards'] == MAILBOX_OR_FORWARDS.forwards:
            if 'forwards' not in data or not data['forwards']:
                self.add_error('forwards', _('No forward addresses selected'))
        else:
            raise forms.ValidationError(
                _('Illegal choice for target of the mail address'))

    def save(self, commit=True):
        """
        Save the mail address.

        :param boolean commit:
        """
        data = self.cleaned_data
        if data['mailbox_or_forwards'] == MAILBOX_OR_FORWARDS.mailbox:
            self.instance.set_mailbox(data['mailbox'], commit)
        elif data['mailbox_or_forwards'] == MAILBOX_OR_FORWARDS.forwards:
            targets = [part.strip() for part in data['forwards'].split(',')]
            self.instance.set_forward_addresses(targets, commit)
        return self.instance