from enum import unique
from statistics import mode
from django.db import models


class User(models.Model):

    creator = models.ForeignKey(
        'self', on_delete=models.DO_NOTHING,
        related_name='created_users'
    )
    created_at = models.DateTimeField(auto_now_add=True)
    modifier_id = models.IntegerField(blank=True, null=True)
    last_modified_at = models.DateTimeField(auto_now=True)
    deleted_at = models.DateTimeField(blank=True, null=True, default=None)
    username = models.CharField(max_length=150)
    name = models.CharField(max_length=128, blank=True, null=True)
    introduction = models.CharField(max_length=255, blank=True, null=True)
    avatar_url = models.CharField(max_length=255, blank=True, null=True)
    openid = models.CharField(max_length=255, unique=True)
    enable = models.BooleanField(default=True)
    phone_number = models.CharField(max_length=32, blank=True, null=True)
    company_name = models.CharField(max_length=100, blank=True, null=True)
    company_name = models.CharField(max_length=32, blank=True, null=True)
    roles = models.ManyToManyField('blog.Role', related_name='users', db_table='user_roles')

    class Meta:
        db_table = 'users'
        managed = False

    def __str__(self):
        return self.username


class Role(models.Model):
    name = models.CharField(max_length=255)
    display_name = models.CharField(max_length=255)

    class Meta:
        db_table = 'roles'
        managed = False

    def __str__(self):
        return self.name


class Tag(models.Model):
    creator_id = models.IntegerField(blank=True, null=True, default=1)
    created_at = models.DateTimeField(auto_now_add=True)
    modifier_id = models.IntegerField(blank=True, null=True, default=1)
    last_modified_at = models.DateTimeField(auto_now=True)
    deleted_at = models.DateTimeField(blank=True, null=True, default=None)
    name = models.CharField(max_length=64, unique=True)
    description = models.CharField(max_length=255, blank=True, null=True)
    slug = models.SlugField(max_length=128, unique=True)
    weight = models.IntegerField(default=10)

    class Meta:
        db_table = 'tags'
        managed = False

    def __str__(self):
        return self.name


class Category(models.Model):
    creator_id = models.IntegerField(blank=True, null=True, default=1)
    created_at = models.DateTimeField(auto_now_add=True)
    modifier_id = models.IntegerField(blank=True, null=True, default=1)
    last_modified_at = models.DateTimeField(auto_now=True)
    deleted_at = models.DateTimeField(blank=True, null=True, default=None)
    name = models.CharField(max_length=64, unique=True)
    description = models.CharField(max_length=512, blank=True, null=True)
    slug = models.SlugField(max_length=128, unique=True)
    weight = models.IntegerField(default=10)

    class Meta:
        db_table = 'categories'
        managed = False

    def __str__(self):
        return self.name


class Post(models.Model):

    STATUS_DRAFT = 'DRAFT'
    STATUS_PENDING = 'PENDING'
    STATUS_PUBLISHED = 'PUBLISHED'
    STATUS_REJECTED = 'REJECTED'
    STATUS_DELETED = 'DELETED'
    STATUS_CHOICES = (
        (STATUS_PUBLISHED, '已发布'),
        (STATUS_DRAFT, '草稿'),
        (STATUS_PENDING, '待审核'),
        (STATUS_REJECTED, '已拒绝'),
        (STATUS_DELETED, '已删除'),
    )

    ORIGIN_ORIGINAL = 'ORIGINAL'
    ORIGIN_REPOST = 'REPOST'
    ORIGIN_CHOICES = (
        (ORIGIN_ORIGINAL, '原创'),
        (ORIGIN_REPOST, '转载'),
    )
    
    creator = models.ForeignKey(
        'blog.User', on_delete=models.DO_NOTHING,
        related_name='created_posts'
    )
    created_at = models.DateTimeField(auto_now_add=True)
    modifier = models.ForeignKey(
        'blog.User', on_delete=models.DO_NOTHING,
        related_name='modified_posts'
    )
    last_modified_at = models.DateTimeField(auto_now=True)
    deleted_at = models.DateTimeField(blank=True, null=True, default=None)
    version = models.IntegerField(default=1)
    title = models.CharField(max_length=255, blank=True, null=True)
    content = models.TextField(blank=True, null=True)
    status = models.CharField(max_length=255, choices=STATUS_CHOICES, default=STATUS_DRAFT)
    origin = models.CharField(max_length=255, choices=ORIGIN_CHOICES, default=ORIGIN_ORIGINAL)
    source_url = models.CharField(max_length=512, blank=True, null=True)
    author = models.ForeignKey(
        'blog.User', on_delete=models.DO_NOTHING,
        related_name='authored_posts'
    )
    category = models.ForeignKey(
        'blog.Category', on_delete=models.DO_NOTHING,
        blank=True, null=True
    )
    recommended = models.BooleanField(default=False)
    recommender = models.ForeignKey(
        'blog.User', on_delete=models.DO_NOTHING,
        related_name='recommended_posts'
    )
    recommended_at = models.DateTimeField(blank=True, null=True)
    publisher = models.ForeignKey(
        'blog.User', on_delete=models.DO_NOTHING,
        related_name='published_posts', blank=True, null=True
    )
    published_at = models.DateTimeField(blank=True, null=True)
    cover_image_url = models.CharField(max_length=512, blank=True, null=True)
    slug = models.CharField(max_length=128, blank=True, null=True)
    from_topic_id = models.IntegerField(blank=True, null=True)
    last_published_at = models.DateTimeField(blank=True, null=True)
    last_publisher = models.ForeignKey(
        'blog.User', on_delete=models.DO_NOTHING,
        related_name='last_published_posts', blank=True, null=True
    )

    class Meta:
        db_table = 'posts'
        managed = False


class Like(models.Model):
    # CREATE TABLE `likes` (
    # `post_id` bigint(20) NOT NULL,
    # `user_id` bigint(20) NOT NULL,
    # `liked_at` datetime NOT NULL DEFAULT CURRENT_TIMESTAMP,
    #  PRIMARY KEY (`post_id`,`user_id`),
    # ....
    # ) ENGINE=InnoDB DEFAULT CHARSET=utf8;
    #
    # Django do not support composite primary key,
    # due we won't insert/update records or make schema migration in this app,
    # so just set primary key on `user` to skip this issue.
    user = models.OneToOneField(
        'blog.User', on_delete=models.DO_NOTHING, primary_key=True)
    post = models.ForeignKey(
        'blog.Post', on_delete=models.DO_NOTHING)
    liked_at = models.DateTimeField(auto_now_add=True)

    class Meta:
        db_table = 'likes'
        managed = False
        unique_together = (('user', 'post'),)


class Favorite(models.Model):
    # ditto.
    user = models.OneToOneField(
        'blog.User', on_delete=models.DO_NOTHING, primary_key=True)
    post = models.ForeignKey(
        'blog.Post', on_delete=models.DO_NOTHING)
    favorited_at = models.DateTimeField(auto_now_add=True)

    class Meta:
        db_table = 'favorites'
        managed = False
        unique_together = (('user', 'post'),)