from django.db import models
from django.core.validators import MaxLengthValidator
from django.utils import timezone
from datetime import datetime, timedelta
from webtools import settings
from django.utils.translation import gettext_lazy as _
import shortuuid



class Language(models.Model):
    """Language object."""

    name = models.CharField(max_length=200, unique=True)
    slug = models.SlugField(max_length=200, unique=True)

    @classmethod
    def by_name(cls, name):
        language = cls.objects.filter(name__icontains=name).first()
        if not language:
            language = cls.objects.filter(
                name__iexact=settings.PASTE["default_language"]
            ).first()
        return language

    def __unicode__(self):
        """String representation."""
        return _(self.name)

    def __str__(self):
        return str(_(self.name))


class Paste(models.Model):
    """Paste object."""

    language = models.ForeignKey(
        Language, default=14, on_delete=models.SET_NULL, null=True
    )
    slug = models.SlugField(unique=True, editable=False)
    content = models.TextField(
        validators=[MaxLengthValidator(settings.PASTE["max_characters"])]
    )
    size = models.IntegerField(default=0, editable=False)
    paste_time = models.DateTimeField(default=datetime.now, editable=False)
    viewcount = models.IntegerField(default=0, editable=False)

    def compute_size(self):
        """Computes size."""
        self.size = len(self.content)

    def get_age(self):
        """Return age in minutes"""
        delta = timezone.now() - self.paste_time
        return divmod(delta.days * 86400 + delta.seconds, 60)[0]

    def incr_viewcount(self):
        """Increment view counter."""
        self.viewcount = self.viewcount + 1
        self.save()

    def __str__(self):
        excerpt = repr(self.content[:100]) + ("..." if len(self.content) > 100 else "")
        return f"{self.slug} - {excerpt}"

    def choose_slug(self):
        while True:
            uuid = shortuuid.uuid()
            for i in range(4, len(uuid)):
                potential_uuid = uuid[:i]
                if not type(self).objects.filter(slug=potential_uuid):
                    self.slug = potential_uuid
                    return