一、开发背景:

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




class CourseCategory(models.Model):
    """课程大类, e.g 前端  后端..."""
    name = models.CharField(max_length=64, unique=True)

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

    class Meta:
        verbose_name = "课程大类"
        verbose_name_plural = "课程大类"


class CourseSubCategory(models.Model):
    """课程子类, e.g python linux """
    category = models.ForeignKey("CourseCategory")
    name = models.CharField(max_length=64, unique=True)

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

    class Meta:
        verbose_name = "课程子类"
        verbose_name_plural = "课程子类"


class DegreeCourse(models.Model):
    """学位课程"""
    name = models.CharField(max_length=128, unique=True)
    course_img = models.CharField(max_length=255, verbose_name="缩略图")
    brief = models.TextField(verbose_name="学位课程简介", )
    total_scholarship = models.PositiveIntegerField(verbose_name="总奖学金(贝里)", default=40000)
    mentor_compensation_bonus = models.PositiveIntegerField(verbose_name="本课程的导师辅导费用(贝里)", default=15000)
    # 忽略,用于GenericForeignKey反向查询， 不会生成表字段，切勿删除
    coupon = GenericRelation("Coupon")

    # 为了计算学位奖学金
    period = models.PositiveIntegerField(verbose_name="建议学习周期(days)", default=150)
    prerequisite = models.TextField(verbose_name="课程先修要求", max_length=1024)
    teachers = models.ManyToManyField("Teacher", verbose_name="课程讲师")

    # 忽略，用于GenericForeignKey反向查询，不会生成表字段，切勿删除
    degreecourse_price_policy = GenericRelation("PricePolicy")

    def __str__(self):
        return self.name


class Scholarship(models.Model):
    """学位课程奖学金"""
    degree_course = models.ForeignKey("DegreeCourse")
    time_percent = models.PositiveSmallIntegerField(verbose_name="奖励档位(时间百分比)", help_text="只填百分值，如80,代表80%")
    value = models.PositiveIntegerField(verbose_name="奖学金数额")

    def __str__(self):
        return "%s:%s" % (self.degree_course, self.value)



class Course(models.Model):
    """课程"""
    name = models.CharField(max_length=128, unique=True)
    course_img = models.CharField(max_length=255)
    sub_category = models.ForeignKey("CourseSubCategory")

    course_type_choices = ((0, '付费'), (1, 'VIP专享'), (2, '学位课程'))
    course_type = models.SmallIntegerField(choices=course_type_choices)
    degree_course = models.ForeignKey("DegreeCourse", blank=True, null=True, help_text="若是学位课程，此处关联学位表")

    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")
    attachment_path = models.CharField(max_length=128, verbose_name="课件路径", blank=True, null=True)
    status_choices = ((0, '上线'), (1, '下线'), (2, '预上线'))
    status = models.SmallIntegerField(choices=status_choices, default=0)
    template_id = models.SmallIntegerField("前端模板id", default=1)

    coupon = GenericRelation("Coupon")

    # 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 "%s(%s)" % (self.name, self.get_course_type_display())

    def save(self, *args, **kwargs):
        if self.course_type == 2:
            if not self.degree_course:
                raise ValueError("学位课程必须关联对应的学位表")
        super(Course, self).save(*args, **kwargs)


class PricePolicy(models.Model):
    """价格与有课程效期表"""
    content_type = models.ForeignKey(ContentType)
    object_id = models.PositiveIntegerField()
    content_object = GenericForeignKey('content_type', 'object_id')

    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)
    price = models.FloatField()

    class Meta:
        unique_together = ("content_type", 'object_id', "valid_period")

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



class CourseDetail(models.Model):
    """课程详情页内容"""
    course = models.OneToOneField("Course")
    hours = models.IntegerField("课时")
    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)
    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 OftenAskedQuestion(models.Model):
    """常见问题"""
    content_type = models.ForeignKey(ContentType,limit_choices_to={'model__contains': 'course'})  # 关联course or degree_course
    object_id = models.PositiveIntegerField()
    content_object = GenericForeignKey('content_type', 'object_id')

    question = models.CharField(max_length=255)
    answer = models.TextField(max_length=1024)

    def __str__(self):
        return "%s-%s" % (self.content_object, self.question)

    class Meta:
        unique_together = ('content_type', 'object_id', 'question')


class CourseOutline(models.Model):
    """课程大纲"""
    course_detail = models.ForeignKey("CourseDetail")
    title = models.CharField(max_length=128)
    # 前端显示顺序
    order = models.PositiveSmallIntegerField(default=1)

    content = models.TextField("内容", max_length=2048)

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

    class Meta:
        unique_together = ('course_detail', 'title')


class CourseChapter(models.Model):
    """课程章节"""
    course = models.ForeignKey("Course", related_name='coursechapters')
    chapter = models.SmallIntegerField(verbose_name="第几章", default=1)
    name = models.CharField(max_length=128)
    summary = models.TextField(verbose_name="章节介绍", blank=True, null=True)
    pub_date = models.DateField(verbose_name="发布日期", auto_now_add=True)

    class Meta:
        unique_together = ("course", 'chapter')

    def __str__(self):
        return "%s:(第%s章)%s" % (self.course, self.chapter, self.name)


class CourseSection(models.Model):
    """课时目录"""
    chapter = models.ForeignKey("CourseChapter", related_name='coursesections')
    name = models.CharField(max_length=128)
    order = models.PositiveSmallIntegerField(verbose_name="课时排序", help_text="建议每个课时之间空1至2个值，以备后续插入课时")
    section_type_choices = ((0, '文档'), (1, '练习'), (2, '视频'))
    section_type = models.SmallIntegerField(default=2, choices=section_type_choices)
    # vid: cc视频，唯一标识：Dfadljfosdfjlsdfjs
    section_link = models.CharField(max_length=255, blank=True, null=True, help_text="若是video，填vid,若是文档，填link")

    video_time = models.CharField(verbose_name="视频时长", blank=True, null=True, max_length=32)  # 仅在前端展示使用


    pub_date = models.DateTimeField(verbose_name="发布时间", auto_now_add=True)
    free_trail = models.BooleanField("是否可试看", default=False)


    class Meta:
        unique_together = ('chapter', 'section_link')


    def __str__(self):
        return "%s-%s" % (self.chapter, self.name)

class Homework(models.Model):
    chapter = models.ForeignKey("CourseChapter")
    title = models.CharField(max_length=128, verbose_name="作业题目")
    order = models.PositiveSmallIntegerField("作业顺序", help_text="同一课程的每个作业之前的order值间隔1-2个数")
    homework_type_choices = ((0, '作业'), (1, '模块通关考核'))
    homework_type = models.SmallIntegerField(choices=homework_type_choices, default=0)
    requirement = models.TextField(max_length=1024, verbose_name="作业需求")
    threshold = models.TextField(max_length=1024, verbose_name="踩分点")
    recommend_period = models.PositiveSmallIntegerField("推荐完成周期(天)", default=7)
    scholarship_value = models.PositiveSmallIntegerField("为该作业分配的奖学金(贝里)")
    note = models.TextField(blank=True, null=True)
    enabled = models.BooleanField(default=True, help_text="本作业如果后期不需要了，不想让学员看到，可以设置为False")

    class Meta:
        unique_together = ("chapter", "title")

    def __str__(self):
        return "%s - %s" % (self.chapter, self.title)

class Teacher(models.Model):
    """讲师、导师表"""
    name = models.CharField(max_length=32)
    role_choices = ((0, '讲师'), (1, '导师'))
    role = models.SmallIntegerField(choices=role_choices, default=0)
    title = models.CharField(max_length=64, verbose_name="职位、职称")
    signature = models.CharField(max_length=255, help_text="导师签名", blank=True, null=True)
    image = models.CharField(max_length=128)
    brief = models.TextField(max_length=1024)

    def __str__(self):
        return self.name

# 普通课购买课程后，我的订单中去评价。
class CourseReview(models.Model):
    """课程评价"""
    enrolled_course = models.OneToOneField("EnrolledCourse")
    about_teacher = models.FloatField(default=0, verbose_name="讲师讲解是否清晰")
    about_video = models.FloatField(default=0, verbose_name="内容实用")
    about_course = models.FloatField(default=0, verbose_name="课程内容通俗易懂")
    review = models.TextField(max_length=1024, verbose_name="评价")
    disagree_number = models.IntegerField(default=0, verbose_name="踩")
    agree_number = models.IntegerField(default=0, verbose_name="赞同数")
    date = models.DateTimeField(auto_now_add=True, verbose_name="评价日期")
    is_recommend = models.BooleanField("热评推荐", default=False)
    hide = models.BooleanField("不在前端页面显示此条评价", default=False)

    def __str__(self):
        return "%s-%s" % (self.enrolled_course.course, self.review)

# 学位课购买课程后，我的订单中去天报名表，然后就编程去学习（以后去评价）。
class DegreeCourseReview(models.Model):
    """学位课程评价
    为了以后可以定制单独的评价内容，所以不与普通课程的评价混在一起，单独建表
    """
    enrolled_course = models.ForeignKey("EnrolledDegreeCourse")
    course = models.ForeignKey("Course", verbose_name="评价学位模块", blank=True, null=True,
                               help_text="不填写即代表评价整个学位课程", limit_choices_to={'course_type': 2})
    about_teacher = models.FloatField(default=0, verbose_name="讲师讲解是否清晰")
    about_video = models.FloatField(default=0, verbose_name="视频质量")
    about_course = models.FloatField(default=0, verbose_name="课程")
    review = models.TextField(max_length=1024, verbose_name="评价")
    disagree_number = models.IntegerField(default=0, verbose_name="踩")
    agree_number = models.IntegerField(default=0, verbose_name="赞同数")

    date = models.DateTimeField(auto_now_add=True, verbose_name="评价日期")
    is_recommend = models.BooleanField("热评推荐", default=False)
    hide = models.BooleanField("不在前端页面显示此条评价", default=False)

    def __str__(self):
        return "%s-%s" % (self.enrolled_course, self.review)

# 购买学位课后，为每个学生每个模块会立刻生成一条学习纪录（未开通）
class StudyRecord(models.Model):
    """学位课程的模块学习进度
       报名学位课程后，每个模块会立刻生成一条学习纪录
    """
    enrolled_degree_course = models.ForeignKey("EnrolledDegreeCourse")
    course_module = models.ForeignKey("Course", verbose_name="学位模块", limit_choices_to={'course_type': 2})
    open_date = models.DateField(blank=True, null=True, verbose_name="开通日期")
    end_date = models.DateField(blank=True, null=True, verbose_name="完成日期")
    status_choices = ((2, '在学'), (1, '未开通'), (0, '已完成'))
    status = models.SmallIntegerField(choices=status_choices, default=1)

    class Meta:
        unique_together = ('enrolled_degree_course', 'course_module')

    def __str__(self):
        return '%s-%s' % (self.enrolled_degree_course, self.course_module)

    def save(self, *args, **kwargs):
        if self.course_module.degree_course_id != self.enrolled_degree_course.degree_course_id:
            raise ValueError("学员要开通的模块必须与其报名的学位课程一致！")

        super(StudyRecord, self).save(*args, **kwargs)

# 为学生开通一个模块
class CourseSchedule(models.Model):
    """课程进度计划表,针对学位课程，每开通一个模块，就为这个学员生成这个模块的推荐学习计划表，后面的奖惩均按此表进行"""
    study_record = models.ForeignKey("StudyRecord")
    homework = models.ForeignKey("Homework")
    recommend_date = models.DateField("推荐交作业日期")

    def __str__(self):
        return "%s - %s - %s " % (self.study_record, self.homework, self.recommend_date)

    class Meta:
        unique_together = ('study_record', 'homework')

# 学生交作业
class HomeworkRecord(models.Model):
    """学员作业记录及成绩"""
    homework = models.ForeignKey("Homework")
    student = models.ForeignKey("EnrolledDegreeCourse", verbose_name="学生")
    score_choices = (
        (100, 'A+'),
        (90, 'A'),
        (85, 'B+'),
        (80, 'B'),
        (70, 'B-'),
        (60, 'C+'),
        (50, 'C'),
        (40, 'C-'),
        (-1, 'D'),
        (0, 'N/A'),
        (-100, 'COPY'),
    )
    score = models.SmallIntegerField(verbose_name="分数", choices=score_choices, null=True, blank=True)
    mentor = models.ForeignKey("Account", related_name="my_stu_homework_record", limit_choices_to={'role': 1},
                               verbose_name="导师")
    mentor_comment = models.TextField(verbose_name="导师批注", blank=True, null=True)  # 导师
    status_choice = (
        (0, '待批改'),
        (1, '已通过'),
        (2, '不合格'),
    )
    status = models.SmallIntegerField(verbose_name='作业状态', choices=status_choice, default=0)

    submit_num = models.SmallIntegerField(verbose_name='提交次数', default=0)
    correct_date = models.DateTimeField('备注日期', blank=True, null=True)
    note = models.TextField(blank=True, null=True)
    date = models.DateTimeField("作业提交日期", auto_now_add=True)

    check_date = models.DateTimeField("批改日期", null=True, blank=True)

    update_time = models.DateTimeField(auto_now=True, verbose_name="提交日期")

    # homework_path = models.CharField(verbose_name='作业路径', max_length=256,blank=True,null=True) 作业路径可以动态拿到，没必要存

    reward_choice = (
        (0, '新提交'),
        (1, '按时提交'),
        (2, '未按时提交'),
        (3, '成绩已奖励'),
        (4, '成绩已处罚'),
        (5, '未作按时检测'),
    )
    reward_status = models.SmallIntegerField(verbose_name='作业记录奖惩状态', default=0)

    def __str__(self):
        return "%s %s" % (self.homework, self.student)

    class Meta:
        unique_together = ("homework", "student")

# 导师跟进记录
class StuFollowUpRecord(models.Model):
    """学员跟进记录"""
    enrolled_degree_course = models.ForeignKey("EnrolledDegreeCourse", verbose_name="学生")
    mentor = models.ForeignKey("Account", related_name='mentor', limit_choices_to={'role': 1}, verbose_name="导师")
    followup_tool_choices = ((0, 'QQ'), (1, '微信'), (2, '电话'), (3, '系统通知'))
    followup_tool = models.SmallIntegerField(choices=followup_tool_choices, default=1)
    record = models.TextField(verbose_name="跟进记录")
    attachment_path = models.CharField(max_length=128, blank=True, null=True, verbose_name="附件路径",
                                       help_text="跟进记录的截图等")
    date = models.DateTimeField(auto_now_add=True)

    def __str__(self):
        return "%s --%s --%s" % (self.enrolled_degree_course, self.record, self.date)

# ######################## 深科技 ########################
class ArticleSource(models.Model):
    """文章来源"""
    name = models.CharField(max_length=64, unique=True)

    def __str__(self):
        return self.name


class Article(models.Model):
    """文章资讯"""
    title = models.CharField(max_length=255, unique=True, db_index=True, verbose_name="标题")
    source = models.ForeignKey("ArticleSource", verbose_name="来源")
    article_type_choices = ((0, '资讯'), (1, '视频'))
    article_type = models.SmallIntegerField(choices=article_type_choices, default=0)
    brief = models.TextField(max_length=512, verbose_name="摘要")
    head_img = models.CharField(max_length=255)
    content = models.TextField(verbose_name="文章正文")
    pub_date = models.DateTimeField(verbose_name="上架日期")
    offline_date = models.DateTimeField(verbose_name="下架日期")
    status_choices = ((0, '在线'), (1, '下线'))
    status = models.SmallIntegerField(choices=status_choices, default=0, verbose_name="状态")
    order = models.SmallIntegerField(default=0, verbose_name="权重", help_text="文章想置顶，可以把数字调大，不要超过1000")
    vid = models.CharField(max_length=128, verbose_name="视频VID", help_text="文章类型是视频, 则需要添加视频VID", blank=True, null=True)
    comment_num = models.SmallIntegerField(default=0, verbose_name="评论数")
    agree_num = models.SmallIntegerField(default=0, verbose_name="点赞数")
    view_num = models.SmallIntegerField(default=0, verbose_name="观看数")
    collect_num = models.SmallIntegerField(default=0, verbose_name="收藏数")

    # tags = models.ManyToManyField("Tags", blank=True, verbose_name="标签")
    date = models.DateTimeField(auto_now_add=True, verbose_name="创建日期")

    position_choices = ((0, '信息流'), (1, 'banner大图'), (2, 'banner小图'))
    position = models.SmallIntegerField(choices=position_choices, default=0, verbose_name="位置")

    # comment = GenericRelation("Comment")  # 用于GenericForeignKey反向查询， 不会生成表字段，切勿删除，如有疑问请联系老村长

    def __str__(self):
        return "%s-%s" % (self.source, self.title)


class Collection(models.Model):
    """收藏"""
    content_type = models.ForeignKey(ContentType)
    object_id = models.PositiveIntegerField()
    content_object = GenericForeignKey('content_type', 'object_id')

    account = models.ForeignKey("Account")
    date = models.DateTimeField(auto_now_add=True)

    class Meta:
        unique_together = ('content_type', 'object_id', 'account')


class Comment(models.Model):
    """通用的评论表"""
    # content_type = models.ForeignKey(ContentType, blank=True, null=True, verbose_name="类型")
    # object_id = models.PositiveIntegerField(blank=True, null=True)
    # content_object = GenericForeignKey('content_type', 'object_id')
    # FK(Article)
    article = models.ForeignKey('Article')
    p_node = models.ForeignKey("self", blank=True, null=True, verbose_name="父级评论")
    content = models.TextField(max_length=1024)
    account = models.ForeignKey("Account", verbose_name="会员名")
    disagree_number = models.IntegerField(default=0, verbose_name="踩")
    agree_number = models.IntegerField(default=0, verbose_name="赞同数")
    date = models.DateTimeField(auto_now_add=True)

    def __str__(self):
        return self.content

# ######################## 购买课程相关 ########################

class EnrolledCourse(models.Model):
    """已报名课程,不包括学位课程"""
    account = models.ForeignKey("Account")
    course = models.ForeignKey("Course", limit_choices_to=~Q(course_type=2))
    enrolled_date = models.DateTimeField(auto_now_add=True)
    valid_begin_date = models.DateField(verbose_name="有效期开始自")
    valid_end_date = models.DateField(verbose_name="有效期结束至")
    status_choices = ((0, '已开通'), (1, '已过期'))
    status = models.SmallIntegerField(choices=status_choices, default=0)
    order_detail = models.OneToOneField("OrderDetail")  # 使订单购买后支持 课程评价

    # order = models.ForeignKey("Order",blank=True,null=True)

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

class DegreeRegistrationForm(models.Model):
    """学位课程报名表"""
    enrolled_degree = models.OneToOneField("EnrolledDegreeCourse")
    current_company = models.CharField(max_length=64, )
    current_position = models.CharField(max_length=64, )
    current_salary = models.IntegerField()
    work_experience_choices = (
        (0, "应届生"),
        (1, "1年"),
        (2, "2年"),
        (3, "3年"),
        (4, "4年"),
        (5, "5年"),
        (6, "6年"),
        (7, "7年"),
        (8, "8年"),
        (9, "9年"),
        (10, "10年"),
        (11, "超过10年"),
    )
    work_experience = models.IntegerField()
    open_module = models.BooleanField("是否开通第1模块", default=True)
    stu_specified_mentor = models.CharField("学员自行指定的导师名", max_length=32, blank=True, null=True)
    study_plan_choices = ((0, "1-2小时/天"),
                          (1, "2-3小时/天"),
                          (2, "3-5小时/天"),
                          (3, "5小时+/天"),
                          )
    study_plan = models.SmallIntegerField(choices=study_plan_choices, default=1)
    why_take_this_course = models.TextField("报此课程原因", max_length=1024)
    why_choose_us = models.TextField("为何选路飞", max_length=1024)
    your_expectation = models.TextField("你的期待", max_length=1024)
    memo = models.CharField(max_length=255, blank=True, null=True)

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

class EnrolledDegreeCourse(models.Model):
    """已报名的学位课程"""
    account = models.ForeignKey("Account")
    degree_course = models.ForeignKey("DegreeCourse")
    enrolled_date = models.DateTimeField(auto_now_add=True)
    valid_begin_date = models.DateField(verbose_name="有效期开始自", blank=True, null=True)  # 开通第一个模块时，再添加课程有效期，2年
    valid_end_date = models.DateField(verbose_name="有效期结束至", blank=True, null=True)
    status_choices = (
        (0, '在学中'),
        (1, '休学中'),
        (2, '已毕业'),
        (3, '超时结业'),
        (4, '未开始'),
        # (3, '其它'),
    )
    study_status = models.SmallIntegerField(choices=status_choices, default=0)
    mentor = models.ForeignKey("Account", verbose_name="导师", related_name='my_students',
                               blank=True, null=True, limit_choices_to={'role': 1})
    mentor_fee_balance = models.PositiveIntegerField("导师费用余额", help_text="这个学员的导师费用，每有惩罚，需在此字段同时扣除")
    order_detail = models.OneToOneField("OrderDetail")  # 使订单购买后支持填写报名表

    def __str__(self):
        return "%s:%s" % (self.account, self.degree_course)

    class Meta:
        unique_together = ('account', 'degree_course')

class Coupon(models.Model):
    """优惠券生成规则"""
    name = models.CharField(max_length=64, verbose_name="活动名称")
    brief = models.TextField(blank=True, null=True, verbose_name="优惠券介绍")
    coupon_type_choices = ((0, '通用券'), (1, '满减券'), (2, '折扣券'))
    coupon_type = models.SmallIntegerField(choices=coupon_type_choices, default=0, verbose_name="券类型")

    money_equivalent_value = models.IntegerField(verbose_name="等值货币")
    off_percent = models.PositiveSmallIntegerField("折扣百分比", help_text="只针对折扣券，例7.9折，写79", blank=True, null=True)
    minimum_consume = models.PositiveIntegerField("最低消费", default=0, help_text="仅在满减券时填写此字段")

    content_type = models.ForeignKey(ContentType, blank=True, null=True)
    object_id = models.PositiveIntegerField("绑定课程", blank=True, null=True, help_text="可以把优惠券跟课程绑定")
    content_object = GenericForeignKey('content_type', 'object_id')

    quantity = models.PositiveIntegerField("数量(张)", default=1)
    open_date = models.DateField("优惠券领取开始时间")
    close_date = models.DateField("优惠券领取结束时间")
    valid_begin_date = models.DateField(verbose_name="有效期开始时间", blank=True, null=True)
    valid_end_date = models.DateField(verbose_name="有效结束时间", blank=True, null=True)
    coupon_valid_days = models.PositiveIntegerField(verbose_name="优惠券有效期（天）", blank=True, null=True,
                                                    help_text="自券被领时开始算起")
    date = models.DateTimeField(auto_now_add=True)

    def __str__(self):
        return "%s(%s)" % (self.get_coupon_type_display(), self.name)

    def save(self, *args, **kwargs):
        if not self.coupon_valid_days or (self.valid_begin_date and self.valid_end_date):
            if self.valid_begin_date and self.valid_end_date:
                if self.valid_end_date <= self.valid_begin_date:
                    raise ValueError("valid_end_date 有效期结束日期必须晚于 valid_begin_date ")
            if self.coupon_valid_days == 0:
                raise ValueError("coupon_valid_days 有效期不能为0")
        if self.close_date < self.open_date:
            raise ValueError("close_date 优惠券领取结束时间必须晚于 open_date优惠券领取开始时间 ")

        super(Coupon, self).save(*args, **kwargs)

class CouponRecord(models.Model):
    """优惠券发放、消费纪录"""
    coupon = models.ForeignKey("Coupon")
    # number = models.CharField(max_length=64, unique=True)
    account = models.ForeignKey("Account", verbose_name="拥有者")
    status_choices = ((0, '未使用'), (1, '已使用'), (2, '已过期'),)
    status = models.SmallIntegerField(choices=status_choices, default=0)
    get_time = models.DateTimeField(verbose_name="领取时间", help_text="用户领取时间")
    used_time = models.DateTimeField(blank=True, null=True, verbose_name="使用时间")
    order = models.ForeignKey("Order", blank=True, null=True, verbose_name="关联订单")  # 一个订单可以有多个优惠券

class Order(models.Model):
    """订单"""
    payment_type_choices = ((0, '微信'), (1, '支付宝'), (2, '优惠码'), (3, '贝里'))
    payment_type = models.SmallIntegerField(choices=payment_type_choices)
    payment_number = models.CharField(max_length=128, verbose_name="支付第3方订单号", null=True, blank=True)
    order_number = models.CharField(max_length=128, verbose_name="订单号", unique=True)  # 考虑到订单合并支付的问题
    account = models.ForeignKey("Account")
    actual_amount = models.FloatField(verbose_name="实付金额")

    status_choices = ((0, '交易成功'), (1, '待支付'), (2, '退费申请中'), (3, '已退费'), (4, '主动取消'), (5, '超时取消'))
    status = models.SmallIntegerField(choices=status_choices, verbose_name="状态")
    date = models.DateTimeField(auto_now_add=True, verbose_name="订单生成时间")
    pay_time = models.DateTimeField(blank=True, null=True, verbose_name="付款时间")
    cancel_time = models.DateTimeField(blank=True, null=True, verbose_name="订单取消时间")

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

class OrderDetail(models.Model):
    """订单详情"""
    order = models.ForeignKey("Order")

    content_type = models.ForeignKey(ContentType)  # 可关联普通课程或学位
    object_id = models.PositiveIntegerField()
    content_object = GenericForeignKey('content_type', 'object_id')

    original_price = models.FloatField("课程原价")
    price = models.FloatField("折后价格")
    content = models.CharField(max_length=255, blank=True, null=True)  # ？
    valid_period_display = models.CharField("有效期显示", max_length=32)  # 在订单页显示
    valid_period = models.PositiveIntegerField("有效期(days)")  # 课程有效期
    memo = models.CharField(max_length=255, blank=True, null=True)

    # def __str__(self):
    #     return "%s - %s - %s" % (self.order, self.content_type, self.price)

    class Meta:
        # unique_together = ("order", 'course')
        unique_together = ("order", 'content_type', 'object_id')

class TransactionRecord(models.Model):
    """贝里交易纪录"""
    account = models.ForeignKey("Account")
    amount = models.IntegerField("金额")
    balance = models.IntegerField("账户余额")
    transaction_type_choices = ((0, '收入'), (1, '支出'), (2, '退款'), (3, "提现"))  # 2 为了处理 订单过期未支付时，锁定期贝里的回退
    transaction_type = models.SmallIntegerField(choices=transaction_type_choices)

    content_type = models.ForeignKey(ContentType, blank=True, null=True)
    object_id = models.PositiveIntegerField(blank=True, null=True, verbose_name="关联对象")
    content_object = GenericForeignKey('content_type', 'object_id')

    transaction_number = models.CharField(unique=True, verbose_name="流水号", max_length=128)
    date = models.DateTimeField(auto_now_add=True)
    memo = models.CharField(max_length=128, blank=True, null=True)

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


# ######################## 用户 ########################
class Account(models.Model):
    username = models.CharField("用户名", max_length=64, unique=True)
    password = models.CharField('password', max_length=128)

class UserAuthToken(models.Model):
    """
    用户Token表
    """
    user = models.OneToOneField(to="Account")
    token = models.CharField(max_length=40)
    created = models.DateTimeField(auto_now_add=True)

整个支付流程

一、添加到购物车

当用户选择需要购买的课程和价格策略后，有两种方式购买课程:

一:直接购买,将课程id和选择的价格策略放到redis中，跳到去支付页面，从redis中获取购买课程的id和价格策略id,如果该用户要使用优惠券和贝利,则选择当前用户所拥有并且未使用和没过期的优惠券,得到折后价格,点击去支付完成支付,

二、添加到购物车中完成支付(post)

获取到所选课程的id和所选择的价格策略id传到后端，在后端获取到所选课程的id和所选择的价格策略id，根据课程id获取到当前课程,然后根据当前课程获取到当前课程所有的价格策略,判断在后端获取到的价格策略id在不在当前课程的价格策略中,不在的话则抛出异常价格策略不存在，在的话继续执行，将该课程所有价格策略的id，时间周期和价格存放到price_policy_list中

 price_policy_objs = course_obj.price_policy.all()
            for item in price_policy_objs:
                if item.id == price_policy_id:
                    flag = True
                price_policy_list.append({'id':item.id,
                                          'valid_period':item.get_valid_period_display(),
                                          'price':item.price})

继续将该课程的所有信息主要包括:课程id,课程图片地址,课程标题，所有价格策略，默认价格策略封装在course_dict中

course_dict = {
                'id':course_obj.id,
                'img':course_obj.course_img,
                'title':course_obj.name,
                'price_policy_list':price_policy_list,
                'default_policy_id':price_policy_id
            }

判断当前用户的购物车中是否有东西,没有的话则把当前课程放入到购物车中,如果购物车中已经有课程课程,则将该课程添加到购物车中，最后封装好放到redis中：

  nothing = CONN.hget(settings.LUFFY_SHOPPING_CAR,request.user.id)
            if not nothing:
                data = {course_obj.id: course_dict}
            else:
                data = json.loads(nothing.decode('utf-8'))
                data[course_obj.id] = course_dict

            CONN.hset(settings.LUFFY_SHOPPING_CAR,request.user.id, json.dumps(data))

封装在redis中的数据结构如下:

  chopping_car = {
            request.user.id:{
                course.id:{
                        title:'xx',
                        img:'xx',
                        choice_policy_id:1,
                        price_policy_list:[
                            {id:1,price:'9.9', period:'1个月'},
                            {id:2,price:'19.9',period:'3个月'},
                            {id:3,price:'59.9',period:'8个月'},
                        ],
                    }
                }，
                course.id:[
                        title:'xx',
                        img:'xx',
                        choice_policy_id:1,
                        price_policy_list:[
                            {id:1,price:'9.9', period:'1个月'},
                            {id:2,price:'19.9',period:'3个月'},
                            {id:3,price:'59.9',period:'8个月'},
                        ],
                    ]
                }
            }
        }

from rest_framework.views import APIView
from rest_framework.response import Response
from django.core.exceptions import ObjectDoesNotExist
from api import models
from api.utils.auth.api_view import AuthAPIView
from api.utils.exception import PricePolicyDoesNotExist
from pool import POOL
import json
from django.conf import settings

import redis
CONN = redis.Redis(connection_pool=POOL)

class ShoppingCarView(AuthAPIView,APIView):

    def get(self,request,*args,**kwargs):
        """
        查看购物车
        :param request:
        :param args:
        :param kwargs:
        :return:
        """
        course = CONN.hget(settings.LUFFY_SHOPPING_CAR,request.user.id)
        course_dict = json.loads(course.decode('utf-8'))
        return Response(course_dict)

    def post(self,request,*args,**kwargs):
        """
        获取课程ID和价格策略ID，放入redis
        :param request:
        :param args:
        :param kwargs:
        :return:
        """
        ret = {'code':1000,'msg':None}
        try:
            course_id = request.data.get('course_id')

            price_policy_id = request.data.get('price_policy_id')

            # 1. 获取课程
            course_obj = models.Course.objects.get(id=course_id)
            # 2. 获取当前课程的所有价格策略: id, 有效期，价格
            price_policy_list = []
            flag = False
            price_policy_objs = course_obj.price_policy.all()
            for item in price_policy_objs:
                if item.id == price_policy_id:
                    flag = True
                price_policy_list.append({'id':item.id,
                                          'valid_period':item.get_valid_period_display(),
                                          'price':item.price})
            if not flag:
                raise PricePolicyDoesNotExist()

            # 3. 课程和价格策略均没有问题，将课程和价格策略放到redis中
            # 课程id,课程图片地址,课程标题，所有价格策略，默认价格策略
            course_dict = {
                'id':course_obj.id,
                'img':course_obj.course_img,
                'title':course_obj.name,
                'price_policy_list':price_policy_list,
                'default_policy_id':price_policy_id
            }

            # a. 获取当前用户购物车中的课程 car = {1: {,,,}, 2:{....}}
            # b. car[course_obj.id] = course_dict
            # c. conn.hset('luffy_shopping_car',request.user.id,car)
            nothing = CONN.hget(settings.LUFFY_SHOPPING_CAR,request.user.id)
            if not nothing:
                data = {course_obj.id: course_dict}
            else:
                data = json.loads(nothing.decode('utf-8'))
                data[course_obj.id] = course_dict

            CONN.hset(settings.LUFFY_SHOPPING_CAR,request.user.id, json.dumps(data))

        except ObjectDoesNotExist as e:
            ret['code'] = 1001
            ret['msg'] = "课程不存在"
        except PricePolicyDoesNotExist as e:
            ret['code'] = 1002
            ret['msg'] = "价格策略不存在"
        except Exception as e:
            ret['code'] = 1003
            ret['msg'] = "添加购物车异常"
        print()
        return Response(ret)


    def patch(self,request,*args,**kwargs):
        '''
        修改价格策略,课程id不变,价格策略id变化
        :param reques:
        :param args:
        :param kwargs:
        :return:
        '''
        ret = {'code': 1000, 'msg': None}
        try:
            #课程id
            course_id = request.data.get('course_id')
            course_id=str(course_id)
            #修改后的价格策略id
            price_policy_id = request.data.get('price_policy_id')
            #当前用户的购物车
            cart=CONN.hget(settings.LUFFY_SHOPPING_CAR,request.user.id)
            print(cart)
            if not cart:
                raise  Exception('访问的购物车不存在')


            cart=json.loads(cart.decode('utf-8'))
            #判断课程师傅在当前用户的购物车中
            if course_id not in cart:
                raise Exception('该课程在购物车中不存在')

            #当前课程所有的价格策略
            currentCourse_price_police= cart[course_id]['price_policy_list']

            policy_exit=False
            #如果当前选择的价格策略在当前的课程策略中
            for price_policy in currentCourse_price_police:
                if price_policy['id']==price_policy_id:
                    policy_exit=True
                    break

            if not policy_exit:
                raise PricePolicyDoesNotExist()
            #将购物车中的当前课程的价格策略设置为当前的价格策略
            cart[course_id]['default_policy_id']=price_policy_id
            CONN.hset(settings.LUFFY_SHOPPING_CAR,request.user.id,json.dumps(cart))
            print(cart)

        except PricePolicyDoesNotExist as e:
            ret['code'] = 1001
            ret['msg'] = '价格策略不存在'

        except Exception as e:
            ret['code']=1002
            ret['msg']=str(e)
        return Response(ret)


    def delete(self,request,*args,**kwargs):
        ret = {'code': 1000, 'msg': None}
        try:
            course_id=request.data.get('course_id')
            course_id=str(course_id)
            #获取当前用户的购物车
            cart=CONN.hget(settings.LUFFY_SHOPPING_CAR,request.user.id)
            print(cart)
            #如果没有购物车
            if not cart:
                raise  Exception('购物车里面没有东西')

            cart=json.loads(cart.decode('utf-8'))
            #当前用户购物车中没有该课程
            if course_id not in cart:
                raise Exception('所删除的课程没在购物车中')

            #删除该课程
            del cart[course_id]

            #写入到redis中
            CONN.hset(settings.LUFFY_SHOPPING_CAR,request.user.id,json.dumps(cart))
        except Exception as e:
            ret['code']=1001
            ret['msg']=str(e)

        return Response(ret)

修改购物车总的价格策略(patch):

向后台发课程id和要修改为的价格策略id,判断课程是否在购物车中,判断传递过来的价格策略是否在当前课程的价格策略中,在的话将 redis中的当前课程的默认价格策略修改为当前的价格策略具体将上面代码

二、去结算

前端向后端传递要去结算的课程的id列表如:[1,2]

1.获取用户提交的课程id, [1,2],

判断是否选择要结算的课程,没选择则抛出异常

 course_id_list = request.data.get('course_list')
            if not course_id_list or not isinstance(course_id_list, list):
                raise Exception('请选择要结算的课程')

2.检测购物车中检查是否已经有课程（应该有课程的）

 product_dict = redis_pool.conn.hget(settings.LUFFY_SHOPPING_CAR, request.user.id)
            if not product_dict:
                raise Exception('购物车无课程')

3.检测购物车中是否有用户要购买的课程

            product_dict = json.loads(product_dict.decode('utf-8'))

            # ###### 课程、价格和优惠券 #######
            policy_course_dict = {}

            # 循环用户传递过来的要结算的课程ID列表
            for course_id in course_id_list:
                course_id = str(course_id)
                product = product_dict.get(course_id)
                if not product:
                    raise Exception('购买的课程必须先加入购物车')

如果所结算的课程在购物车中，4.获取选中价格策略的价格详细，

选择购物车中当前课程下的所有价格策略和当前课程的所选择的价格策略相等的价格策略，获取其信息,

            # c. 购物车中是否有用户要购买的课程
            product_dict = json.loads(product_dict.decode('utf-8'))

            # ###### 课程、价格和优惠券 #######
            policy_course_dict = {}

            # 循环用户传递过来的要结算的课程ID列表
            for course_id in course_id_list:
                course_id = str(course_id)
                product = product_dict.get(course_id)
                if not product:
                    raise Exception('购买的课程必须先加入购物车')

                # 获取选中价格策略的价格详细
                policy_exist = False
                for policy in product['price_policy_list']:
                    if policy['id'] == product['choice_policy_id']:
                        policy_price = policy['price']
                        policy_period = policy['period']
                        policy_valid_period = policy['valid_period']
                        policy_exist = True
                        break
                if not policy_exist:
                    raise Exception('购物车中的课程无此价格')