from django.db import models
from django.contrib.auth.models import User
from django.utils import timezone
from django.core.cache import cache
# from django.conf import settings
import string  # random
from hashids import Hashids


hashids = Hashids(salt="srct.gmu.edu", alphabet=(string.ascii_lowercase + string.digits))


class URL(models.Model):
    """
    This model represents a stored URL redirection rule. Each URL has an
    owner, target url, short identifier, click counter, and expiration
    date.
    """

    owner = models.ForeignKey(User)
    date_created = models.DateTimeField(default=timezone.now)

    target = models.URLField(max_length=1000)
    short = models.SlugField(primary_key=True, max_length=20)
    clicks = models.IntegerField(default=0)

    qrclicks = models.IntegerField(default=0)
    socialclicks = models.IntegerField(default=0)

    expires = models.DateTimeField(blank=True, null=True)

    def __unicode__(self):
        return '<%s : %s>' % (self.owner.username, self.target)

    class Meta:
        ordering = ['short']

    @staticmethod
    def generate_valid_short():
        if cache.get("hashids_counter") == None:
            cache.set("hashids_counter", URL.objects.count())
        cache.incr("hashids_counter")
        short = hashids.encrypt(cache.get("hashids_counter"))
        tries = 1
        while tries < 100:
            try:
                urls = URL.objects.get(short__iexact=short)
                tries += 1
                cache.incr("hashids_counter")
            except URL.DoesNotExist:
                return short
        return None

class RegisteredUser(models.Model):
    """
    This is simply a wrapper model which, if an object exists, indicates
    that that user is registered.
    """

    username = models.CharField(
        blank=False,
        max_length=30,
        primary_key=True
    )

    full_name = models.CharField(
        blank=False,
        max_length=100,
    )

    description = models.TextField(blank=True)

    approved = models.BooleanField()

    def __unicode__(self):
        return '<Registered User: %s - Approval Status: %s>' % (self.username, self.approved)