课程列表接口，课程详情接口（）

from django.db import models
from django.contrib.contenttypes.models import ContentType
from django.contrib.contenttypes.fields import GenericForeignKey, GenericRelation

# Create your models here.
# class CourseType(models.Model):
#     type_name = models.CharField(verbose_name=‘课程类别‘,max_length=32)
# class Course(models.Model):
#     title = models.CharField(verbose_name=‘课程名称‘,max_length=32)
#     course_info = models.CharField(verbose_name=‘课程描述‘,max_length=128)
#     student_num = models.IntegerField()
#     choice = ((1,‘初级‘),(2,‘中级‘),(3,‘高级‘))
#     student_level = models.IntegerField(verbose_name=‘级别‘,choices=choice)
#     course_price = models.IntegerField()
# class CourseDetail(models.Model):
#     course = models.OneToOneField(to=‘Course‘)
#     contents = models.CharField(verbose_name=‘所学内容‘,max_length=128)
#     time = models.CharField(verbose_name=‘时长‘,max_length=32)
#     choice = ((1, ‘初级‘), (2, ‘中级‘), (3, ‘高级‘))
#     student_level = models.IntegerField(verbose_name=‘级别‘, choices=choice)
#     student_num = models.IntegerField()
#     score = models.IntegerField()
#     recommended_courses = models.CharField(verbose_name=‘推荐课程‘,max_length=32)
# class Price(models.Model):
#     old_price = models.IntegerField(verbose_name=‘原价‘)
#     now_price = models.IntegerField(verbose_name=‘现价‘)
#     content_type = models.ForeignKey(to=ContentType)
#     object_id = models.PositiveIntegerField()
#     content_object = GenericForeignKey("content_type", "object_id")
# class CourseChapter(models.Model):
#     course_detail = models.ForeignKey(to=‘CourseDetail‘)
#
# class ClassHours(models.Model):
#     course_chapter = models.OneToOneField(to=‘CourseChapter‘)
#
# class questions(models.Model):
#     content_type = models.ForeignKey(to=ContentType)
#     object_id = models.PositiveIntegerField()
#     content_object = GenericForeignKey("content_type", "object_id")
# class teacher(models.Model):
#     name = models.CharField(verbose_name=‘姓名‘,max_length=32)
#     choice = ((1,‘男‘),(2,‘女‘))
#     sex = models.IntegerField(verbose_name=‘性别‘,choices=choice)
class Course(models.Model):
    """专题课程"""

    name = models.CharField(max_length=128, unique=True)
    course_img = models.CharField(max_length=255)
    brief = models.TextField(verbose_name="课程概述", max_length=2048)

    level_choices = ((0, ‘初级‘), (1, ‘中级‘), (2, ‘高级‘))
    level = models.SmallIntegerField(choices=level_choices, default=1)
    pub_date = models.DateField(verbose_name="发布日期", blank=True, null=True)
    period = models.PositiveIntegerField(verbose_name="建议学习周期(days)", default=7)
    order = models.IntegerField("课程顺序", help_text="从上一个课程数字往后排")

    status_choices = ((0, ‘上线‘), (1, ‘下线‘), (2, ‘预上线‘))
    status = models.SmallIntegerField(choices=status_choices, default=0)
    # 用于GenericForeignKey反向查询，不会生成表字段，切勿删除
    price_policy = GenericRelation("PricePolicy")

    def __str__(self):
        return self.name

    class Meta:
        verbose_name_plural = "专题课"


class CourseDetail(models.Model):
    """课程详情页内容"""
    course = models.OneToOneField("Course", on_delete=models.CASCADE)
    hours = models.IntegerField("课时")
    # 课程的标语 口号
    course_slogan = models.CharField(max_length=125, blank=True, null=True)
    # video_brief_link = models.CharField(verbose_name=‘课程介绍‘, max_length=255, blank=True, null=True)
    # why_study = models.TextField(verbose_name="为什么学习这门课程")
    # what_to_study_brief = models.TextField(verbose_name="我将学到哪些内容")
    # career_improvement = models.TextField(verbose_name="此项目如何有助于我的职业生涯")
    # prerequisite = models.TextField(verbose_name="课程先修要求", max_length=1024)
    # 推荐课程
    recommend_courses = models.ManyToManyField("Course", related_name="recommend_by", blank=True)
    teachers = models.ManyToManyField("Teacher", verbose_name="课程讲师")

    def __str__(self):
        return "%s" % self.course

    class Meta:
        verbose_name_plural = "课程详细"


class PricePolicy(models.Model):
    """价格与有课程效期表"""
    price = models.FloatField()


    # course = models.ForeignKey("Course")
    valid_period_choices = ((1, ‘1天‘), (3, ‘3天‘),
                            (7, ‘1周‘), (14, ‘2周‘),
                            (30, ‘1个月‘),
                            (60, ‘2个月‘),
                            (90, ‘3个月‘),
                            (180, ‘6个月‘), (210, ‘12个月‘),
                            (540, ‘18个月‘), (720, ‘24个月‘),
                            )
    valid_period = models.SmallIntegerField(choices=valid_period_choices)

    content_type = models.ForeignKey(ContentType, on_delete=models.CASCADE)  # 关联course or degree_course
    object_id = models.PositiveIntegerField()
    content_object = GenericForeignKey(‘content_type‘, ‘object_id‘)


    class Meta:
        unique_together = ("content_type", ‘object_id‘, "valid_period")
        verbose_name_plural = "价格策略"


    def __str__(self):
        return "%s(%s)%s" % (self.content_object, self.get_valid_period_display(), self.price)


class Teacher(models.Model):
    """讲师、导师表"""
    name = models.CharField(max_length=32)
    image = models.CharField(max_length=128)
    brief = models.TextField(max_length=1024)

    def __str__(self):
        return self.name

    class Meta:
        verbose_name_plural = "讲师"