#
# This file is part of FreedomBox.
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License as
# published by the Free Software Foundation, either version 3 of the
# License, or (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU Affero General Public License for more details.
#
# You should have received a copy of the GNU Affero General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.
#
"""
Forms for backups module.
"""

from django import forms
from django.core import validators
from django.core.validators import FileExtensionValidator
from django.utils.translation import ugettext, ugettext_lazy as _

from plinth.utils import format_lazy
from plinth import cfg

from . import api


def _get_app_choices(apps):
    """Return a list of check box multiple choices from list of apps."""
    choices = []
    for app in apps:
        name = app.app.name
        if not app.has_data:
            name = ugettext('{app} (No data to backup)').format(
                app=app.app.name)

        choices.append((app.name, name))

    return choices


class CreateArchiveForm(forms.Form):
    name = forms.CharField(
        label=_('Archive name'), strip=True,
        help_text=_('Name for new backup archive.'), validators=[
            validators.RegexValidator(r'^[^/]+$', _('Invalid archive name'))
        ])

    selected_apps = forms.MultipleChoiceField(
        label=_('Included apps'), help_text=_('Apps to include in the backup'),
        widget=forms.CheckboxSelectMultiple)

    def __init__(self, *args, **kwargs):
        """Initialize the form with selectable apps."""
        super().__init__(*args, **kwargs)
        apps = api.get_all_apps_for_backup()
        self.fields['selected_apps'].choices = _get_app_choices(apps)
        self.fields['selected_apps'].initial = [app.name for app in apps]


class RestoreForm(forms.Form):
    selected_apps = forms.MultipleChoiceField(
        label=_('Select the apps you want to restore'),
        widget=forms.CheckboxSelectMultiple)

    def __init__(self, *args, **kwargs):
        """Initialize the form with selectable apps."""
        apps = kwargs.pop('apps')
        super().__init__(*args, **kwargs)
        self.fields['selected_apps'].choices = _get_app_choices(apps)
        self.fields['selected_apps'].initial = [app.name for app in apps]


class UploadForm(forms.Form):
    file = forms.FileField(label=_('Upload File'), required=True,
            validators=[FileExtensionValidator(['gz'],
                'Backup files have to be in .tar.gz format')],
            help_text=_('Select the backup file you want to upload'))


class CreateRepositoryForm(forms.Form):
    repository = forms.CharField(
        label=_('Repository path'), strip=True,
        help_text=_('Path of the new repository.'))
    encryption = forms.ChoiceField(
        label=_('Encryption'),
        help_text=format_lazy(_('"Key in Repository" means that a '
            'password-protected key is stored with the backup. <br />'
            '<b>You need this password to restore a backup!</b>')),
        choices=[('repokey', 'Key in Repository'), ('none', 'None')]
        )
    passphrase = forms.CharField(
        label=_('Passphrase'),
        help_text=_('Passphrase; Only needed when using encryption.'),
        widget=forms.PasswordInput()
    )
    confirm_passphrase = forms.CharField(
        label=_('Confirm Passphrase'),
        help_text=_('Repeat the passphrase.'),
        widget=forms.PasswordInput()
    )
    store_passphrase = forms.BooleanField(
        label=_('Store passphrase on FreedomBox'),
        help_text=format_lazy(_('Store the passphrase on your {box_name}.'
            '<br />You need to store the passphrase if you want to run '
            'recurrent backups.'), box_name=_(cfg.box_name)),
        required=False
    )

    def clean(self):
        cleaned_data = super(CreateRepositoryForm, self).clean()
        passphrase = cleaned_data.get("passphrase")
        confirm_passphrase = cleaned_data.get("confirm_passphrase")

        if passphrase != confirm_passphrase:
            raise forms.ValidationError(
                "passphrase and confirm_passphrase do not match"
            )