# (c) Copyright 2014,2015 Hewlett-Packard Development Company, L.P.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#    http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

import datetime

from django.urls import reverse
from django.utils.translation import gettext_lazy as _


from horizon import exceptions
from horizon import forms
from horizon import workflows

import freezer_ui.api.api as freezer_api


class SessionConfigurationAction(workflows.Action):
    description = forms.CharField(
        label=_("Session Name"),
        help_text=_("Define a name for this session"))

    session_id = forms.CharField(
        widget=forms.HiddenInput(),
        required=False)

    schedule_start_date = forms.CharField(
        label=_("Start Date and Time"),
        required=False,
        help_text=_(
            "Optional. Start time for the session in ISO format: "
            "YYYY-MM-DDTHH:MM:SS (for example: 2026-02-06T14:30:00). "
            "If not provided, the session will start immediately."
        )
    )

    schedule_interval = forms.CharField(
        label=_("Interval"),
        required=False,
        help_text=_("""Set the interval in the following format:
                       continuous,
                       N weeks,
                       N days,
                       N hours,
                       N minutes,
                       N seconds,
                       If no start date is provided the job
                       will start immediately"""))

    schedule_end_date = forms.CharField(
        label=_("End Date and Time"),
        required=False,
        help_text=_(
            "Optional. End time for the session in ISO format: "
            "YYYY-MM-DDTHH:MM:SS (for example: 2026-02-06T18:00:00). "
            "If not provided, the session will run indefinitely "
            "or until manually stopped."
        )
    )

    def clean(self):
        cleaned_data = super(SessionConfigurationAction, self).clean()
        self._check_start_datetime(cleaned_data)
        self._check_end_datetime(cleaned_data)
        return cleaned_data

    def _validate_iso_format(self, start_date):
        try:
            return datetime.datetime.strptime(
                start_date, "%Y-%m-%dT%H:%M:%S")
        except ValueError:
            return False

    def _check_start_datetime(self, cleaned_data):
        if cleaned_data.get('start_datetime') and not \
                self._validate_iso_format(
                    cleaned_data.get('schedule_start_date')):
            msg = _("Start date time is not in ISO format.")
            self._errors['schedule_start_date'] = self.error_class([msg])

    def _check_end_datetime(self, cleaned_data):
        if cleaned_data.get('end_datetime') and not \
                self._validate_iso_format(
                    cleaned_data.get('schedule_end_date')):
            msg = _("End date time is not in ISO format.")
            self._errors['schedule_end_date'] = self.error_class([msg])

    class Meta:
        name = _("Session Information")
        slug = "freezer-sessions"
        help_text_template = "project/freezer-sessions" \
                             "/_info.html"


class SessionConfiguration(workflows.Step):
    action_class = SessionConfigurationAction
    contributes = ('description',
                   'session_id',
                   'schedule_start_date',
                   'schedule_interval',
                   'schedule_end_date')


class CreateSession(workflows.Workflow):
    slug = "create_session"
    name = _("Create Session")
    finalize_button_name = _("Save")
    success_message = _('Session queued correctly. It will appear soon.')
    failure_message = _('Unable to create session.')
    success_url = "horizon:project:freezer-sessions:index"
    default_steps = (SessionConfiguration,)

    def handle(self, request, context):
        try:
            if context['session_id'] != '':
                freezer_api.Session(request).update(context,
                                                    context['session_id'])
            else:
                freezer_api.Session(request).create(context)
            return reverse("horizon:project:freezer-sessions:index")
        except Exception:
            exceptions.handle(request)
            return False
