boards/models/post.py

from datetime import datetime, timedelta, date
from datetime import time as dtime
import logging
import re

from django.core.cache import cache
from django.core.urlresolvers import reverse
from django.db import models, transaction
from django.template.loader import render_to_string
from django.utils import timezone
from markupfield.fields import MarkupField

from boards.models import PostImage
from boards.models.base import Viewable
from boards.models.thread import Thread


APP_LABEL_BOARDS = 'boards'

CACHE_KEY_PPD = 'ppd'
CACHE_KEY_POST_URL = 'post_url'

POSTS_PER_DAY_RANGE = 7

BAN_REASON_AUTO = 'Auto'

IMAGE_THUMB_SIZE = (200, 150)

TITLE_MAX_LENGTH = 200

DEFAULT_MARKUP_TYPE = 'bbcode'

# TODO This should be removed
NO_IP = '0.0.0.0'

# TODO Real user agent should be saved instead of this
UNKNOWN_UA = ''

REGEX_REPLY = re.compile(r'\[post\](\d+)\[/post\]')

logger = logging.getLogger(__name__)


class PostManager(models.Manager):
    def create_post(self, title, text, image=None, thread=None, ip=NO_IP,
                    tags=None):
        """
        Creates new post
        """

        if not tags:
            tags = []

        posting_time = timezone.now()
        if not thread:
            thread = Thread.objects.create(bump_time=posting_time,
                                           last_edit_time=posting_time)
            new_thread = True
        else:
            thread.bump()
            thread.last_edit_time = posting_time
            thread.save()
            new_thread = False

        post = self.create(title=title,
                           text=text,
                           pub_time=posting_time,
                           thread_new=thread,
                           poster_ip=ip,
                           poster_user_agent=UNKNOWN_UA,  # TODO Get UA at
                           # last!
                           last_edit_time=posting_time)

        if image:
            post_image = PostImage.objects.create(image=image)
            post.images.add(post_image)
            logger.info('Created image #%d for post #%d' % (post_image.id,
                                                            post.id))

        thread.replies.add(post)
        list(map(thread.add_tag, tags))

        if new_thread:
            Thread.objects.process_oldest_threads()
        self.connect_replies(post)

        logger.info('Created post #%d with title %s' % (post.id,
                                                        post.get_title()))

        return post

    def delete_post(self, post):
        """
        Deletes post and update or delete its thread
        """

        post_id = post.id

        thread = post.get_thread()

        if post.is_opening():
            thread.delete()
        else:
            thread.last_edit_time = timezone.now()
            thread.save()

            post.delete()

        logger.info('Deleted post #%d (%s)' % (post_id, post.get_title()))

    def delete_posts_by_ip(self, ip):
        """
        Deletes all posts of the author with same IP
        """

        posts = self.filter(poster_ip=ip)
        for post in posts:
            self.delete_post(post)

    def connect_replies(self, post):
        """
        Connects replies to a post to show them as a reflink map
        """

        for reply_number in re.finditer(REGEX_REPLY, post.text.raw):
            post_id = reply_number.group(1)
            ref_post = self.filter(id=post_id)
            if ref_post.count() > 0:
                referenced_post = ref_post[0]
                referenced_post.referenced_posts.add(post)
                referenced_post.last_edit_time = post.pub_time
                referenced_post.build_refmap()
                referenced_post.save(update_fields=['refmap', 'last_edit_time'])

                referenced_thread = referenced_post.get_thread()
                referenced_thread.last_edit_time = post.pub_time
                referenced_thread.save(update_fields=['last_edit_time'])

    def get_posts_per_day(self):
        """
        Gets average count of posts per day for the last 7 days
        """

        day_end = date.today()
        day_start = day_end - timedelta(POSTS_PER_DAY_RANGE)

        cache_key = CACHE_KEY_PPD + str(day_end)
        ppd = cache.get(cache_key)
        if ppd:
            return ppd

        day_time_start = timezone.make_aware(datetime.combine(
            day_start, dtime()), timezone.get_current_timezone())
        day_time_end = timezone.make_aware(datetime.combine(
            day_end, dtime()), timezone.get_current_timezone())

        posts_per_period = float(self.filter(
            pub_time__lte=day_time_end,
            pub_time__gte=day_time_start).count())

        ppd = posts_per_period / POSTS_PER_DAY_RANGE

        cache.set(cache_key, ppd)
        return ppd


class Post(models.Model, Viewable):
    """A post is a message."""

    objects = PostManager()

    class Meta:
        app_label = APP_LABEL_BOARDS
        ordering = ('id',)

    title = models.CharField(max_length=TITLE_MAX_LENGTH)
    pub_time = models.DateTimeField()
    text = MarkupField(default_markup_type=DEFAULT_MARKUP_TYPE,
                       escape_html=False)

    images = models.ManyToManyField(PostImage, null=True, blank=True,
                                    related_name='ip+', db_index=True)

    poster_ip = models.GenericIPAddressField()
    poster_user_agent = models.TextField()

    thread_new = models.ForeignKey('Thread', null=True, default=None,
                                   db_index=True)
    last_edit_time = models.DateTimeField()

    referenced_posts = models.ManyToManyField('Post', symmetrical=False,
                                              null=True,
                                              blank=True, related_name='rfp+',
                                              db_index=True)
    refmap = models.TextField(null=True, blank=True)

    def __unicode__(self):
        return '#' + str(self.id) + ' ' + self.title + ' (' + \
               self.text.raw[:50] + ')'

    def get_title(self):
        """
        Gets original post title or part of its text.
        """

        title = self.title
        if not title:
            title = self.text.rendered

        return title

    def build_refmap(self):
        """
        Builds a replies map string from replies list. This is a cache to stop
        the server from recalculating the map on every post show.
        """
        map_string = ''

        first = True
        for refpost in self.referenced_posts.all():
            if not first:
                map_string += ', '
            map_string += '<a href="%s">&gt;&gt;%s</a>' % (refpost.get_url(),
                                                           refpost.id)
            first = False

        self.refmap = map_string

    def get_sorted_referenced_posts(self):
        return self.refmap

    def is_referenced(self):
        return len(self.refmap) > 0

    def is_opening(self):
        """
        Checks if this is an opening post or just a reply.
        """

        return self.get_thread().get_opening_post_id() == self.id

    @transaction.atomic
    def add_tag(self, tag):
        edit_time = timezone.now()

        thread = self.get_thread()
        thread.add_tag(tag)
        self.last_edit_time = edit_time
        self.save(update_fields=['last_edit_time'])

        thread.last_edit_time = edit_time
        thread.save(update_fields=['last_edit_time'])

    @transaction.atomic
    def remove_tag(self, tag):
        edit_time = timezone.now()

        thread = self.get_thread()
        thread.remove_tag(tag)
        self.last_edit_time = edit_time
        self.save(update_fields=['last_edit_time'])

        thread.last_edit_time = edit_time
        thread.save(update_fields=['last_edit_time'])

    def get_url(self, thread=None):
        """
        Gets full url to the post.
        """

        cache_key = CACHE_KEY_POST_URL + str(self.id)
        link = cache.get(cache_key)

        if not link:
            if not thread:
                thread = self.get_thread()

            opening_id = thread.get_opening_post_id()

            if self.id != opening_id:
                link = reverse('thread', kwargs={
                    'post_id': opening_id}) + '#' + str(self.id)
            else:
                link = reverse('thread', kwargs={'post_id': self.id})

            cache.set(cache_key, link)

        return link

    def get_thread(self):
        """
        Gets post's thread.
        """

        return self.thread_new

    def get_referenced_posts(self):
        return self.referenced_posts.only('id', 'thread_new')

    def get_text(self):
        return self.text

    def get_view(self, moderator=False, need_open_link=False,
                 truncated=False, *args, **kwargs):
        if 'is_opening' in kwargs:
            is_opening = kwargs['is_opening']
        else:
            is_opening = self.is_opening()

        if 'thread' in kwargs:
            thread = kwargs['thread']
        else:
            thread = self.get_thread()

        if 'can_bump' in kwargs:
            can_bump = kwargs['can_bump']
        else:
            can_bump = thread.can_bump()

        if is_opening:
            opening_post_id = self.id
        else:
            opening_post_id = thread.get_opening_post_id()

        return render_to_string('boards/post.html', {
            'post': self,
            'moderator': moderator,
            'is_opening': is_opening,
            'thread': thread,
            'bumpable': can_bump,
            'need_open_link': need_open_link,
            'truncated': truncated,
            'opening_post_id': opening_post_id,
        })

    def get_first_image(self):
        return self.images.earliest('id')

    def delete(self, using=None):
        """
        Deletes all post images and the post itself.
        """

        self.images.all().delete()

        super(Post, self).delete(using)