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

"""
from __future__ import absolute_import

from crispy_forms.bootstrap import AppendedText
from crispy_forms.helper import FormHelper
from crispy_forms.layout import Div, Layout, Submit
from django import forms
from django.core.validators import validate_email
from django.urls import reverse
from django.utils.translation import gettext_lazy as _
from model_utils import Choices

from gvawebcore.forms import PasswordModelFormMixin

from .models import MailAddress, Mailbox

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,
    )
    # TODO: refactor as separate field class returning a list
    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):
        super(AddMailAddressForm, self).clean()
        data = self.cleaned_data
        if data["mailbox_or_forwards"] == MAILBOX_OR_FORWARDS.mailbox:
            if "mailbox" not in data or 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:  # pragma: no cover
            # should not happen because of the field's validation
            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:  # pragma: no cover
            # should not happen because of the field's validation
            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 super(EditMailAddressForm, self).save(commit)