import datetime

import structlog
from django.utils import timezone
from factory.django import DjangoModelFactory

from .models import DueDate
from ..assignment.models import Assignment
from ..course.models import CourseSession
from ..learnpath.models import LearningContentAttendanceCourse

logger = structlog.get_logger(__name__)


def get_date(date_string):
    return datetime.datetime.strptime(date_string, '%b %d %Y', ).astimezone(timezone.get_current_timezone())


class DueDateFactory(DjangoModelFactory):
    class Meta:
        model = DueDate

    title = "Prüfung Versicherungsvermittler/-in"
    end = get_date("Jan 01 2021")


def generate_events(start=timezone.now()):
    for i in range(20):
        DueDateFactory(title=f"{i}", start=start + datetime.timedelta(days=i),
                       end=start + datetime.timedelta(days=i, hours=1))


def hour_rounder(t):
    # Rounds to nearest hour by adding a timedelta hour if minute >= 30
    return (t.replace(second=0, microsecond=0, minute=0, hour=t.hour)
            + datetime.timedelta(hours=t.minute // 30))


def create_duedates_for_all_course_sessions():
    all_course_sessions: list[CourseSession] = CourseSession.objects.all()

    for course_session in all_course_sessions:
        create_duedates_for_course_session(course_session)


def create_duedates_for_course_session(course_session: CourseSession):
    course = course_session.course
    attendance_courses = list(LearningContentAttendanceCourse.objects.descendant_of(course.get_learning_path()))
    assignments = list(Assignment.objects.descendant_of(course.get_learning_path()))
    contents = attendance_courses + assignments

    for content in contents:
        if callable(getattr(content, 'get_frontend_url', None)):
            url = content.get_frontend_url()

        duedate, created = DueDate.objects.get_or_create(course_session=course_session,
                                                         title=content.title,
                                                         url=url,
                                                         page=content.specific)

        if created:
            pass
        logger.info("Created duedate ", duedate=duedate, course_session=course_session, content=content)


def set_default_times_for_duedates():
    now = hour_rounder(timezone.now())

    for i, event in enumerate(DueDate.objects.filter(end__isnull=True)):
        event.start = now + datetime.timedelta(days=i)
        event.end = event.start + datetime.timedelta(hours=3)
        event.save()