# -*- coding: utf-8 -*-
from django.db import models
from hvad.models import TranslatableModel, TranslatedFields, TranslationManager
from django.template.defaultfilters import slugify
import copy

class ArticleManager(TranslationManager):
    def safe_get(self, **kwargs):
        model = self.model
        try:
            return model.objects.get(**kwargs)
        except:
            return None

class Article(TranslatableModel):
    """
    Create Article model

    Uses hvad.TranslatableModel which is child of django.db.models class

    """
    #set manager of this model
    objects = ArticleManager

    url = models.SlugField(unique=True)
    theme = models.ManyToManyField('theme.Theme')
    tag = models.ManyToManyField('theme.Tag', related_name='tags',blank=True, null=True)
    user = models.ForeignKey('accounts.User', verbose_name='Автор',
                                  on_delete=models.PROTECT, related_name='articles')

    #translated fields
    translations = TranslatedFields(
        main_title = models.CharField(max_length=100),
        preview = models.TextField(),
        description = models.TextField(),
        #-----meta
        title = models.CharField(max_length=255, blank=True),
        descriptions = models.CharField(max_length=255, blank=True),
        keywords = models.CharField(max_length=255, blank=True),
    )

    def __unicode__(self):
        return self.lazy_translation_getter('main_title', self.pk)

    def clone(self):
        """
        Return an identical copy of the instance with a new ID.
        """
        if not self.pk:
            raise ValueError('Instance must be saved before it can be cloned.')

        duplicate = copy.copy(self)
        # Setting pk to None. Django thinking this is a new object.
        duplicate.pk = None
        # url must be unique
        duplicate.url += '_copy'
        if Article.objects.safe_get(url=duplicate.url):
            #already has copy this instance
            return

        duplicate.save()
        # but lost all ManyToMany relations and Translations.

        # copy relations
        for field in self._meta.many_to_many:
            source = getattr(self, field.attname)
            destination = getattr(duplicate, field.attname)
            for item in source.all():
                destination.add(item)

        # copy translations
        languages = self.get_available_languages()
        ignore_fields = ['id', 'master', 'language_code']

        for code in languages:
            duplicate.translate(code)
            tr = self._meta.translations_model.objects.get(language_code = code,master__id=self.pk)
            for field in duplicate._translated_field_names:

                if field in ignore_fields:
                    continue

                setattr(duplicate, field, getattr(tr, field))

            duplicate.save()

        return duplicate