from datetime import datetime

from django.db import models
from django.urls import reverse_lazy
from django.utils.text import slugify
from markdownx.models import MarkdownxField
from markdownx.utils import markdownify
from tagulous.models import TagField


class Category(models.Model):
    title = models.CharField(max_length=40, unique=True)
    slug = models.SlugField(max_length=40, unique=True)
    introduction = models.TextField(blank=True)

    def save(self, force_insert=False, force_update=False, using=None, update_fields=None):
        if not self.slug:
            self.slug = slugify(self.title)
        return super(Category, self).save()

    def get_absolute_url(self):
        return reverse_lazy('articles:list_category', args=[self.slug])

    def __str__(self):
        return self.title

    class Meta:
        ordering = ['title']


class Article(models.Model):
    title = models.CharField(max_length=200)
    subtitle = models.CharField(max_length=200, blank=True, null=True)
    slug = models.SlugField(max_length=200, unique=True)
    category = models.ForeignKey(Category, on_delete=models.PROTECT, related_name='articles')
    introduction = models.TextField(blank=True)
    body = MarkdownxField()
    summary = MarkdownxField(blank=True)
    # FIXME: tags with spaces do not match any articles when clicked on.
    tags = TagField(force_lowercase=True,
                    get_absolute_url=lambda tag: reverse_lazy('articles:list_tag', kwargs={'tag': tag.slug}))
    created = models.DateTimeField(auto_now_add=True)
    updated = models.DateTimeField(auto_now_add=True)
    is_published = models.BooleanField(default=False)
    is_updated = models.BooleanField(default=False)
    is_featured = models.BooleanField(default=False)

    def save(self, force_insert=False, force_update=False, using=None, update_fields=None):
        if not self.slug:
            self.slug = slugify(self.title)
        if self.is_updated:
            self.updated = datetime.now()
            self.is_updated = False
        return super(Article, self).save()

    def get_absolute_url(self):
        return reverse_lazy('articles:detail', args=[self.category.slug, self.slug])

    def body_as_markdown(self):
        return markdownify(self.body)

    def __str__(self):
        return self.title

    class Meta:
        ordering = ['-created']