from django.db import models
from django.contrib.auth.models import User


# Create your models here.

class BaseModel(models.Model):
    """
    Post应用的Model基类
    """

    class Meta:
        abstract = True
        ordering = ['-created_time']

    created_time = models.DateTimeField(auto_now_add=True, help_text=u'创建时间')
    last_modified = models.DateTimeField(auto_now=True, help_text=u'修改时间')

    def __str__(self):
        raise NotImplementedError


class Topic(BaseModel):
    """
    BBS论坛发布话题
    """
    title = models.CharField(max_length=255, unique=True, help_text=u'话题标题')
    content = models.TextField(help_text=u'话题内容')
    is_online = models.BooleanField(default=True, help_text=u'话题是否在线')
    user = models.ForeignKey(to=User, to_field='id', on_delete=models.CASCADE, help_text=u'关联用户表')

    def __str__(self):
        return '%d: %s' % (self.id, self.title)


class Comment(BaseModel):
    """
    BBS话题评论
    """
    content = models.CharField(max_length=255, help_text=u'话题评论')
    topic = models.ForeignKey(to=Topic, to_field='id', on_delete=models.CASCADE, help_text=u'关联话题表')
    up = models.IntegerField(default=0, help_text=u'支持')
    down = models.IntegerField(default=0, help_text=u'反对')

    def __str__(self):
        return '%d:" %s' % (self.id, self.content[0:20])