from django.db import models
from django.utils import timezone

from neboard import settings

import thumbs

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


class PostManager(models.Manager):
    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)

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

        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):
        if tag is None:
            threads = self.filter(parent=NO_PARENT)
        else:
            threads = self.filter(parent=NO_PARENT, tag=tag)

        return threads

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


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
    """

    name = models.CharField(max_length=100)


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

    objects = PostManager()

    title = models.CharField(max_length=100)
    pub_time = models.DateTimeField()
    text = models.TextField()
    image = thumbs.ImageWithThumbsField(upload_to='images/',
                                        blank=True, sizes=((200, 150),))
    poster_ip = models.IPAddressField()
    poster_user_agent = models.TextField()
    parent = models.BigIntegerField()
    tags = models.ManyToManyField(Tag)

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


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)