from django.db import models
from django.urls import reverse
from django.contrib.sitemaps import Sitemap
import datetime
from itertools import chain

from taggit.managers import TaggableManager

from taxonomy.models import TaggedItems
from utils.util import render_images, markdown_to_html
from fieldnotes.models import FieldNote
from books.models import Book
from photos.models import LuxImage


POST_TYPE = (
    (0, 'essays'),
    (1, 'tools'),
    (2, 'figments'),
)


class Essay(models.Model):
    title = models.CharField(max_length=200)
    sub_title = models.CharField(max_length=200, blank=True)
    dek = models.TextField(blank=True)
    preamble = models.TextField(blank=True)
    preamble_html = models.TextField(blank=True)
    slug = models.SlugField(unique_for_date='pub_date')
    body_html = models.TextField(blank=True)
    body_markdown = models.TextField()
    pub_date = models.DateTimeField('Date published')
    last_updated = models.DateTimeField(auto_now=True)
    enable_comments = models.BooleanField(default=False)
    has_code = models.BooleanField(default=False)
    PUB_STATUS = (
        (0, 'Draft'),
        (1, 'Published'),
    )
    status = models.IntegerField(choices=PUB_STATUS, default=0)
    meta_description = models.CharField(max_length=256, null=True, blank=True)
    tags = TaggableManager(through=TaggedItems, blank=True, help_text='Topics Covered')
    originally_published_by = models.CharField(max_length=400, blank=True)
    originally_published_by_url = models.CharField(max_length=400, blank=True)
    featured_image = models.ForeignKey(LuxImage, on_delete=models.CASCADE, null=True, blank=True)
    has_video = models.BooleanField(blank=True, default=False)
    field_notes = models.ManyToManyField(FieldNote, blank=True)
    books = models.ManyToManyField(Book, blank=True)
    afterword = models.TextField(blank=True)
    afterword_html = models.TextField(blank=True)

    class Meta:
        ordering = ('-pub_date',)
        get_latest_by = 'pub_date'
        verbose_name_plural = 'Essays'

    def __str__(self):
        return self.title

    def get_absolute_url(self):
        return reverse('essays:detail', kwargs={"slug": self.slug})

    def comment_period_open(self):
        return self.enable_comments and datetime.datetime.today() - datetime.timedelta(30) <= self.pub_date

    @property
    def get_previous_published(self):
        return self.get_previous_by_pub_date(status__exact=1)

    @property
    def get_next_published(self):
        return self.get_next_by_pub_date(status__exact=1)

    def save(self):
        md = render_images(self.body_markdown)
        self.body_html = markdown_to_html(md)
        self.afterword_html = markdown_to_html(self.afterword)
        self.preamble_html = markdown_to_html(self.preamble)
        super(Essay, self).save()


class EssaySitemap(Sitemap):
    changefreq = "never"
    priority = 1.0
    protocol = "https"

    def items(self):
        return Essay.objects.filter(status=1)

    def lastmod(self, obj):
        return obj.pub_date