boards/models.py

import os
from random import random
import re
from django.db import models
from django.utils import timezone
import time
import math

from neboard import settings
from markupfield.fields import MarkupField

import thumbs

NO_PARENT = -1
NO_IP = '0.0.0.0'
UNKNOWN_UA = ''


class PostManager(models.Manager):
    ALL_PAGES = -1

    def create_post(self, title, text, image=None, parent_id=NO_PARENT,
                    ip=NO_IP, tags=None):
        post = self.create(title=title,
                           text=text,
                           pub_time=timezone.now(),
                           parent=parent_id,
                           image=image,
                           poster_ip=ip,
                           poster_user_agent=UNKNOWN_UA,
                           last_edit_time=timezone.now())

        if tags:
            for tag in tags:
                post.tags.add(tag)

        if parent_id != NO_PARENT:
            self._bump_thread(parent_id)
        else:
            self._delete_old_threads()

        return post

    def delete_post(self, post):
        children = self.filter(parent=post.id)
        for child in children:
            self.delete_post(child)
        post.delete()

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

    def get_threads(self, tag=None, page=ALL_PAGES):
        if tag:
            threads = self.filter(parent=NO_PARENT, tags=tag)
        else:
            threads = self.filter(parent=NO_PARENT)
        threads = list(threads.order_by('-last_edit_time'))

        if page != self.ALL_PAGES:
            thread_count = len(threads)

            if page < self.get_thread_page_count(tag=tag):
                start_thread = page * settings.THREADS_PER_PAGE
                end_thread = min(start_thread + settings.THREADS_PER_PAGE,
                                 thread_count)
                threads = threads[start_thread:end_thread]

        return threads

    def get_thread(self, opening_post_id):
        opening_post = self.get(id=opening_post_id)

        if opening_post.parent == NO_PARENT:
            replies = self.filter(parent=opening_post_id)

            thread = [opening_post]
            thread.extend(replies)

            return thread

    def exists(self, post_id):
        posts = self.filter(id=post_id)

        return len(posts) > 0

    def get_thread_page_count(self, tag=None):
        if tag:
            threads = self.filter(parent=NO_PARENT, tags=tag)
        else:
            threads = self.filter(parent=NO_PARENT)

        return int(math.ceil(len(threads) / float(settings.THREADS_PER_PAGE)))


    def _delete_old_threads(self):
        """
        Preserves maximum thread count. If there are too many threads,
        delete the old ones.
        """

        # TODO Try to find a better way to get the active thread count.

        # TODO Move old threads to the archive instead of deleting them.
        # Maybe make some 'old' field in the model to indicate the thread
        # must not be shown and be able for replying.

        threads = self.get_threads()
        thread_count = len(threads)

        if thread_count > settings.MAX_THREAD_COUNT:
            num_threads_to_delete = thread_count - settings.MAX_THREAD_COUNT
            old_threads = threads[-num_threads_to_delete:]

            for thread in old_threads:
                self.delete_post(thread)

    def _bump_thread(self, thread_id):
        thread = self.get(id=thread_id)

        if thread.can_bump():
            thread.last_edit_time = timezone.now()
            thread.save()


class TagManager(models.Manager):
    def get_not_empty_tags(self):
        all_tags = self.all().order_by('name')
        tags = []
        for tag in all_tags:
            if not tag.is_empty():
                tags.append(tag)

        return tags


class Tag(models.Model):
    """
    A tag is a text node assigned to the post. The tag serves as a board
    section. There can be multiple tags for each message
    """

    objects = TagManager()

    name = models.CharField(max_length=100)
    # TODO Connect the tag to its posts to check the number of threads for
    # the tag.

    def __unicode__(self):
        return self.name

    def is_empty(self):
        return self.get_post_count() == 0

    def get_post_count(self):
        posts_with_tag = Post.objects.get_threads(tag=self)
        return len(posts_with_tag)


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

    IMAGES_DIRECTORY = 'images/'
    FILE_EXTENSION_DELIMITER = '.'

    objects = PostManager()

    def _update_image_filename(self, filename):
        """Get unique image filename"""

        path = self.IMAGES_DIRECTORY
        new_name = str(int(time.mktime(time.gmtime())))
        new_name += str(int(random() * 1000))
        new_name += self.FILE_EXTENSION_DELIMITER
        new_name += filename.split(self.FILE_EXTENSION_DELIMITER)[-1:][0]

        return os.path.join(path, new_name)

    title = models.CharField(max_length=50)
    pub_time = models.DateTimeField()
    text = MarkupField(default_markup_type='markdown', escape_html=True)
    image = thumbs.ImageWithThumbsField(upload_to=_update_image_filename,
                                        blank=True, sizes=((200, 150),))
    poster_ip = models.IPAddressField()
    poster_user_agent = models.TextField()
    parent = models.BigIntegerField()
    tags = models.ManyToManyField(Tag)
    last_edit_time = models.DateTimeField()

    regex_pretty = re.compile(r'^\d(0)+$')
    regex_same = re.compile(r'^(.)\1+$')

    def __unicode__(self):
        return self.title + ' (' + self.text.raw + ')'

    def _get_replies(self):
        return Post.objects.filter(parent=self.id)

    def get_reply_count(self):
        return len(self._get_replies())

    def get_images_count(self):
        images_count = 1 if self.image else 0
        for reply in self._get_replies():
            if reply.image:
                images_count += 1

        return images_count

    def get_gets_count(self):
        gets_count = 1 if self.is_get() else 0
        for reply in self._get_replies():
            if reply.is_get():
                gets_count += 1

        return gets_count

    def is_get(self):
        """If the post has pretty id (1, 1000, 77777), than it is called GET"""

        first = self.id == 1

        id_str = str(self.id)
        pretty = self.regex_pretty.match(id_str)
        same_digits = self.regex_same.match(id_str)

        return first or pretty or same_digits

    def can_bump(self):
        """Check if the thread can be bumped by replying"""

        replies_count = len(Post.objects.get_thread(self.id))

        return replies_count <= settings.MAX_POSTS_PER_THREAD


class Admin(models.Model):
    """
    Model for admin users
    """
    name = models.CharField(max_length=100)
    password = models.CharField(max_length=100)

    def __unicode__(self):
        return self.name + '/' + '*' * len(self.password)