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

from itertools import chain

from django import forms
from django.utils.translation import ugettext as _
from django.utils.encoding import smart_text, force_text
from django.utils.html import format_html
from django.utils.safestring import mark_safe
from django.db.models import Count, Sum

from haystack.query import SearchQuerySet, RelatedSearchQuerySet

from functions.model_utils import EnumChoices
from exposition.models import Exposition
from conference.models import Conference
from theme.models import Theme, Tag


class CountModelMultipleChoiceField(forms.ModelMultipleChoiceField):
    def label_from_instance(self, obj):
        return u'{0} ({count})'.format(smart_text(obj.name), count=obj.e_count + obj.c_count)



### Делаем выборку по темам, сразу заполняя перевод и кол-во событиый
## 1-й рабочий способ (без заполнения перевода)
# """
# SELECT
#     `theme_theme`.`id`,
#     (
#     SELECT COUNT(`exposition_exposition_theme`.`exposition_id`)
#     FROM `exposition_exposition_theme`
#     WHERE (`theme_theme`.`id` = `exposition_exposition_theme`.`theme_id`)
#     ) AS `e_count`,
#     (
#     SELECT COUNT(`conference_conference_theme`.`conference_id`)
#     FROM `conference_conference_theme`
#     WHERE (`theme_theme`.`id` = `conference_conference_theme`.`theme_id`)
#     ) AS `c_count`,
#     `theme_theme_translation`.`name` as `name`
# FROM
#     `theme_theme`
# GROUP BY `theme_theme`.`id`
# ORDER BY NULL
# """

## 2-й рабочий способ (с заполнением перевода)
## аттрибут перевода 'name' присвоен на 'name_t', чтобы не ругалось на неправильно заполненый перевод
# theme_sql = \
# """
# SELECT
#     `theme_theme_translation`.`name` AS `name_t`,
#     `theme_theme_translation`.`master_id` AS `id`,
#     (
#     SELECT COUNT(`exposition_exposition_theme`.`exposition_id`)
#     FROM `exposition_exposition_theme`
#     WHERE (`theme_theme_translation`.`master_id` = `exposition_exposition_theme`.`theme_id`)
#     ) AS `e_count`,
#     (
#     SELECT COUNT(`conference_conference_theme`.`conference_id`)
#     FROM `conference_conference_theme`
#     WHERE (`theme_theme_translation`.`master_id` = `conference_conference_theme`.`theme_id`)
#     ) AS `c_count`
# FROM
#     `theme_theme_translation`
# WHERE (`theme_theme_translation`.`language_code` = 'ru')
# GROUP BY `theme_theme_translation`.`name`
# ORDER BY NULL
# """
# qs = Theme.objects.raw(theme_sql)

## 3-й рабочий способ (с родным заполением перевода)
## в ходе поиска, был найден и 4-й рабочий способ используя RawSQL, но он для Django >= 1.8
## https://docs.djangoproject.com/en/1.9/ref/models/expressions/#raw-sql-expressions
## from django.db.models.expressions import RawSQL
extra_themes_expo_count = '''
SELECT COUNT(`exposition_exposition_theme`.`exposition_id`)
FROM `exposition_exposition_theme`
WHERE (`theme_theme`.`id` = `exposition_exposition_theme`.`theme_id`)
'''
extra_themes_conf_count = '''
SELECT COUNT(`conference_conference_theme`.`conference_id`)
FROM `conference_conference_theme`
WHERE (`theme_theme`.`id` = `conference_conference_theme`.`theme_id`)
'''
extra_themes_select = {
    'e_count': extra_themes_expo_count,
    'c_count': extra_themes_conf_count,
}
themes = Theme.objects.language('ru').extra(select=extra_themes_select)


class FilterForm(forms.Form):
    TYPES = EnumChoices(
        EXPO=(1, _(u'Выставки')),
        CONF=(2, _(_(u'Конференции'))),
    )

    model = forms.TypedMultipleChoiceField(label=_(u'Тип события'), coerce=int, choices=TYPES, required=False, widget=forms.CheckboxSelectMultiple())
    theme = CountModelMultipleChoiceField(label=_(u'Тематики'),
        queryset=themes,
        required=False, widget=forms.CheckboxSelectMultiple())
    # tag = CountModelMultipleChoiceField(label=_(u'Теги'),
    #     queryset=Tag.active.all()\
    #         .annotate(e_count=Count('exposition_tags'), c_count=Count('conference_tags')),
    #     required=False, widget=forms.CheckboxSelectMultiple())


    def get_models(self):
        val = self.cleaned_data.get('model')
        models = []
        if val:
            if self.TYPES.EXPO in val:
                models.append(Exposition)
            if self.TYPES.CONF in val:
                models.append(Conference)
        else:
            models = [Conference, Exposition]
        return models

    def filter(self):
        qs = self.default_filter(self.get_models())
        d = self.cleaned_data
        if d.get('theme'):
            qs = qs.filter(theme__in=d.get('theme'))
        if d.get('tag'):
            qs = qs.filter(tag__in=d.get('tag'))
        return qs

    def default_filter(self, models=None):
        qs = RelatedSearchQuerySet().models(Exposition, Conference).load_all()
        models = models or [Exposition, Conference]
        for model in models:
            qs = qs.load_all_queryset(model, model.enable.all())
        return qs