# -*- coding: utf-8 -*-
import uuid

import unidecode
from django.contrib.postgres.fields import ArrayField
from django.db import models
from django.template.defaultfilters import slugify
from model_utils import Choices

from lms.tools import get_real_name, get_empty_list

COURSE_LEVEL = (
    ('B', 'Базовый'),
    ('A', 'Продвинутый'),
    ('E', 'Экспертный'),
    ('B+A', 'Базовый + Продвинутый'),
)

COURSE_DIRECTION = (
    (3, 'Бизнес'),
    (2, 'Веб-дизайн'),
    (1, 'Разработка'),
    (4, 'Рисование'),
    (5, 'Музыка'),
)


def upload_material(instance, filename):
    return '/'.join([
        'materials', str(instance.topic.course.token), str(instance.topic.id), str(instance.token), filename])


class Lesson(models.Model):
    token = models.UUIDField(verbose_name="Токен", default=uuid.uuid4, editable=False)
    key = models.UUIDField(
        verbose_name="Внутрений ключ используется для расшивровки", default=uuid.uuid4, editable=False)
    topic = models.ForeignKey(to="Topic", verbose_name='Тема')
    title = models.CharField(verbose_name='Название', max_length=255)
    description = models.TextField(verbose_name='Описание', blank=True, null=True)
    video = models.TextField(verbose_name='Код видео', blank=True, null=True)
    materials = ArrayField(
        models.FileField(verbose_name="Материал к уроку", upload_to=upload_material, max_length=255),
        verbose_name="Материалы к уроку",
        default=get_empty_list,
    )
    material_tokens = ArrayField(
        models.UUIDField(verbose_name="Токен материала", editable=False),
        default=get_empty_list,
        verbose_name='Материалы курса',
        blank=True
    )
    free = models.BooleanField(default=False, verbose_name='Привилегии для узла не будут проверяться')
    sort = models.SmallIntegerField(verbose_name='Поле сортировки')

    is_hm = models.BooleanField(default=False) #TODO костыли
    old_id = models.IntegerField(null=True, blank=True)

    def __str__(self):
        return self.title

    class Meta:
        verbose_name = "Урок"
        verbose_name_plural = "Уроки"
        ordering = ('sort', )
        unique_together = ('sort', 'topic')


class Topic(models.Model):
    course = models.ForeignKey(to="Course", verbose_name='курс')
    title = models.CharField(verbose_name='Название', max_length=255)
    sort = models.SmallIntegerField(verbose_name='Поле сортировки')

    def __str__(self):
        return self.title

    class Meta:
        verbose_name = "Тема"
        verbose_name_plural = "Темы"
        ordering = ('sort',)
        unique_together = ('sort', 'course')


def upload_image(instance, _filename):
    return 'courses/%s/image.png' % instance.slug


def upload_big_image(instance, _filename):
    return 'courses/%s/big_image.png' % instance.slug


def upload_mobile_image(instance, _filename):
    return 'courses/%s/mobile_image.png' % instance.slug


def default_slug():
    return slugify(unidecode.unidecode('Python-разработчик с нуля (2018)'))


class Course(models.Model):
    PRODUCERS = Choices('skillbox', 'Ingate', 'AIC')

    token = models.UUIDField(verbose_name="Токен", default=uuid.uuid4, editable=False)
    slug = models.SlugField(unique=True, editable=False, max_length=127, default=default_slug)
    title = models.CharField(verbose_name="Заголовок", max_length=255, unique=True)
    description = models.TextField(verbose_name='Описание', blank=True)
    level = models.CharField(verbose_name='Уровень', choices=COURSE_LEVEL, default='B', max_length=3)
    direction = models.SmallIntegerField(choices=COURSE_DIRECTION, verbose_name='Направление', default=1)
    public = models.BooleanField(verbose_name='Опубликовать', default=False)
    teacher_tokens = ArrayField(
        models.UUIDField(verbose_name="Токен препода", editable=False),
        default=get_empty_list,
        verbose_name='Преподователи курса',
    )
    image = models.ImageField(verbose_name='Изображение', blank=True, max_length=255, upload_to=upload_image)
    big_image = models.ImageField(
        verbose_name='Большое изображение', blank=True, max_length=255, upload_to=upload_big_image)
    big_mobile_image = models.ImageField(verbose_name='Под мобилку', blank=True, upload_to=upload_mobile_image,
                                         help_text='Большая картинка для мобильной версии', max_length=255)
    hidden = models.BooleanField(verbose_name='Видно только оплатившим', default=False)
    producer = models.CharField(
        choices=PRODUCERS, default=PRODUCERS.skillbox, max_length=15, verbose_name="Производитель")

    def __str__(self):
        return self.title

    def get_teacher(self):
        return self.teacher_tokens[0]

    def get_statistic(self):
        return {
            'topic_count': self.topic_set.all().count(),
            'task_count': sum([topic.lesson_set.count() for topic in self.topic_set.all()])
        }

    def get_lesson_list(self) -> list:
        lesson_list = []
        for topic in self.topic_set.all():
            lesson_list += list(topic.lesson_set.all())
        return lesson_list

    def get_next(self, lesson: Lesson, f=None) -> Lesson:
        lessons = self.get_lesson_list()
        try:
            n = lessons[lessons.index(lesson)+1]
            if f is None or f(n):
                return n
            else:
                return self.get_next(n, f)
        except IndexError:
            pass

    def get_previous(self, lesson: Lesson, f=None):
        lessons = self.get_lesson_list()
        idx = lessons.index(lesson) - 1
        if idx > -1:
            prev = lessons[idx]
            if f is None or f(prev):
                return prev
            else:
                return self.get_previous(prev, f)

    def get_first_lesson(self) -> Lesson:
        lessons = self.get_lesson_list()
        try:
            return lessons[0]
        except IndexError:
            pass

    class Meta:
        verbose_name = "Курс"
        verbose_name_plural = "Курсы"


# class LessonRequirement(models.Model):
#     lesson = models.ForeignKey(to=Lesson)
#     requirement = models.ForeignKey(to='courses.Requirement')
#     sort = models.SmallIntegerField(default=1)
#
#     class Meta:
#         verbose_name = "Порядок требований"
#         verbose_name_plural = "Порядок требований"
#         ordering = ('sort', )
#         unique_together = ('lesson', 'requirement', 'sort')
#
#
# class Requirement(models.Model):
#     CHECK_TYPES = Choices('student', 'teacher', 'auto',)
#
#     token = models.UUIDField(verbose_name="Токен", default=uuid.uuid4, primary_key=True, editable=False)
#     name = models.CharField(max_length=31, verbose_name="Название", unique=True)
#     checker = models.CharField(
#         choices=CHECK_TYPES, default=CHECK_TYPES.teacher, max_length=15, verbose_name="Проверяющий",)
#     min_balls = models.SmallIntegerField(default=50, verbose_name='Проходной бал')
#
#     def __str__(self):
#         return self.name
#
#     class Meta:
#         verbose_name = "Требования"
#         verbose_name_plural = "Требования"
#
#
# class Question(models.Model):
#     FIELD_TYPES = Choices('text', 'char', 'boolean', 'file')
#
#     requirement = models.ForeignKey(to=Requirement)
#     text = models.TextField(verbose_name="Вопрос")
#     type = models.CharField(choices=FIELD_TYPES, default=FIELD_TYPES.char, max_length=20)
#     multiple = models.BooleanField(default=False)
#     null = models.BooleanField(default=False)
#     balls = models.SmallIntegerField(default=100, verbose_name='Вознаграждение')
#
#     class Meta:
#         verbose_name = "Вопрос"
#         verbose_name_plural = "Вопросы"
#
#
# class RightAnswer(models.Model):
#     question = models.OneToOneField(to=Question)
#     text = models.TextField(verbose_name="Верный ответ")
#     success_comment = models.TextField(blank=True, null=True, verbose_name="Комментарий при верном ответе")
#     error_comment = models.TextField(blank=True, null=True, verbose_name="Комментарий при ошибке")
#
#     class Meta:
#         verbose_name = "Верный ответ"
#         verbose_name_plural = "Верные ответы"