Software Público Brasileiro

# -*- coding: utf-8 -*-

from hashlib import md5

from django.db import models
from django.conf import settings
from django.utils import timezone
from django.contrib.auth import get_user_model
from django.core.urlresolvers import reverse, NoReverseMatch
from django.utils.translation import ugettext_lazy as _


User = get_user_model()


class NotSpamManager(models.Manager):
    """Only return objects which are not marked as spam."""

    def get_query_set(self):
        return super(NotSpamManager, self).get_query_set().exclude(spam=True)


class PageHit(models.Model):
    url_path = models.CharField(max_length=2048, unique=True, db_index=True)
    hit_count = models.IntegerField(default=0)


class EmailAddress(models.Model):
    user = models.ForeignKey(User, null=True, related_name='emails')
    address = models.EmailField(unique=True)
    real_name = models.CharField(max_length=64, blank=True, db_index=True)
    md5 = models.CharField(max_length=32, null=True)

    def save(self, *args, **kwargs):
        self.md5 = md5(self.address).hexdigest()
        super(EmailAddress, self).save(*args, **kwargs)

    def get_full_name(self):
        if self.user and self.user.get_full_name():
            return self.user.get_full_name()
        elif self.real_name:
            return self.real_name

    def get_full_name_or_anonymous(self):
        return self.get_full_name() or _('Anonymous')

    def __unicode__(self):
        return '"%s" <%s>' % (self.get_full_name(), self.address)


class MailingList(models.Model):
    name = models.CharField(max_length=80)
    email = models.EmailField()
    description = models.TextField()
    logo = models.FileField(upload_to='list_logo') #TODO
    last_imported_index = models.IntegerField(default=0)

    def __unicode__(self):
        return self.name


class MailingListMembership(models.Model):
    user = models.ForeignKey(User)
    mailinglist = models.ForeignKey(MailingList)

    def __unicode__(self):
        return '%s on %s' % (self.user.email, self.mailinglist.name)


class Thread(models.Model):

    subject_token = models.CharField(max_length=512)
    mailinglist = models.ForeignKey(MailingList,
                                    verbose_name=_(u"Mailing List"),
                                    help_text=_(u"The Mailing List where is the thread"))
    latest_message = models.OneToOneField('Message', null=True,
                                                     related_name='+',
                                                     verbose_name=_(u"Latest message"),
                                                     help_text=_(u"Latest message posted"))
    score = models.IntegerField(default=0, verbose_name=_(u"Score"), help_text=_(u"Thread score"))
    spam = models.BooleanField(default=False)

    all_objects = models.Manager()
    objects = NotSpamManager()

    class Meta:
        verbose_name = _(u"Thread")
        verbose_name_plural = _(u"Threads")
        unique_together = ('subject_token', 'mailinglist')

    def __unicode__(self):
        return '%s - %s (%s)' % (self.id,
                                 self.subject_token,
                                 self.message_set.count())

    def update_score(self):
        """Update the relevance score for this thread.

        The score is calculated with the following variables:

        * vote_weight: 100 - (minus) 1 for each 3 days since
          voted with minimum of 5.
        * replies_weight: 300 - (minus) 1 for each 3 days since
          replied with minimum of 5.
        * page_view_weight: 10.

        * vote_score: sum(vote_weight)
        * replies_score: sum(replies_weight)
        * page_view_score: sum(page_view_weight)

        * score = (vote_score + replies_score + page_view_score) // 10
        with minimum of 0 and maximum of 5000

        """

        if not self.subject_token:
            return

        # Save this pseudo now to avoid calling the
        #   function N times in the loops below
        now = timezone.now()
        days_ago = lambda date: (now - date).days
        get_score = lambda weight, created: \
                                  max(weight - (days_ago(created) // 3), 5)

        vote_score = 0
        replies_score = 0
        for msg in self.message_set.all():
            # Calculate replies_score
            replies_score += get_score(300, msg.received_time)

            # Calculate vote_score
            for vote in msg.vote_set.all():
                vote_score += get_score(100, vote.created)

        # Calculate page_view_score
        try:
            url = reverse('thread_view', args=[self.mailinglist.name,
                                               self.subject_token])
            pagehit = PageHit.objects.get(url_path=url)
            page_view_score = pagehit.hit_count * 10
        except (NoReverseMatch, PageHit.DoesNotExist):
            page_view_score = 0

        self.score = (page_view_score + vote_score + replies_score) // 10
        self.save()


class Vote(models.Model):
    user = models.ForeignKey(User)
    message = models.ForeignKey('Message')
    created = models.DateTimeField(auto_now_add=True)

    class Meta:
        unique_together = ('user', 'message')

    def __unicode__(self):
        return 'Vote on %s by %s' % (self.Message.id,
                                     self.user.username)


class Message(models.Model):

    from_address = models.ForeignKey(EmailAddress, db_index=True)
    thread = models.ForeignKey(Thread, null=True, db_index=True)
    # RFC 2822 recommends to use 78 chars + CRLF (so 80 chars) for
    #   the max_length of a subject but most of implementations
    #   goes for 256. We use 512 just in case.
    subject = models.CharField(max_length=512, db_index=True,
                               verbose_name=_(u"Subject"),
                               help_text=_(u"Please enter a message subject"))
    subject_clean = models.CharField(max_length=512, db_index=True)
    body = models.TextField(default='',
                            verbose_name=_(u"Message body"),
                            help_text=_(u"Please enter a message body"))
    received_time = models.DateTimeField()
    message_id = models.CharField(max_length=512)
    spam = models.BooleanField(default=False)

    all_objects = models.Manager()
    objects = NotSpamManager()

    class Meta:
        verbose_name = _(u"Message")
        verbose_name_plural = _(u"Messages")
        unique_together = ('thread', 'message_id')

    def __unicode__(self):
        return '(%s) %s: %s' % (self.id,
                                self.from_address.get_full_name(),
                                self.subject_clean)

    @property
    def mailinglist(self):
        if not self.thread or not self.thread.mailinglist:
            return None

        return self.thread.mailinglist

    def vote_list(self):
        """Return a list of user that voted in this message."""
        return [vote.user for vote in self.vote_set.iterator()]

    def votes_count(self):
        return len(self.vote_list())

    def vote(self, user):
        Vote.objects.create(
            message=self,
            user=user
        )

    def unvote(self, user):
        Vote.objects.get(
            message=self,
            user=user
        ).delete()

    @property
    def url(self):
        """Shortcut to get thread url"""
        return reverse('thread_view', args=[self.mailinglist.name,
                                            self.thread.subject_token])

    @property
    def Description(self):
        """Alias to self.body"""
        return self.body

    @property
    def Title(self):
        """Alias to self.subject_clean"""
        return self.subject_clean

    @property
    def modified(self):
        """Alias to self.modified"""
        return self.received_time


class MessageMetadata(models.Model):
    Message = models.ForeignKey(Message)
    # Same problem here than on subjects. Read comment above
    #   on Message.subject
    name = models.CharField(max_length=512)
    value = models.TextField()

    def __unicode__(self):
        return 'Email Message Id: %s - %s: %s' % (self.Message.id,
                                                  self.name, self.value)