from django.db import models
import operator
from django.db.models import Q
from ox.text import smartSplit
from django.core.paginator import Paginator, InvalidPage, EmptyPage

def splitSearch(string):
  ret = []
  for s in smartSplit(string):
    word = s.replace("'", "").replace('"', '')
    ret.append(word)
  return ret

class ItfModel(models.Model):
  fts_fields = []
  fk_filters = []
  sort_fields = []

  class Meta:
    abstract = True

  def list_dict(self):
    return {}

  def info_dict(self):
    return {}

  @classmethod
  def fts(kls, qset, search):
    terms = splitSearch(search)
    qobjects = []
    for t in terms:  
      for f in kls.fts_fields:
        qstring = f + '__icontains'
        qobject = Q(**{qstring:t})
        qobjects.append(qobject)
    return qset.filter(reduce(operator.or_, qobjects))

  '''
  eg. fks = {
      'somefield': [1, 5, 7],
      'someotherfield': [3]
      }
  '''
  @classmethod
  def filter_by_fks(kls, qset, fks):
    qobjects = []
    for key in fks.keys():
      field = getField(kls._meta.fields, key)
      if field:
#        rel_class = field.related.parent_model
        for i in fks[key]:
          qobject = Q(**{field.name: i})
          qobjects.append(qobject)
    return qset.filter(reduce(operator.or_, qobjects))               

  @classmethod
  def get_fk_objects(kls):
    ret = {}
    for f in kls.fk_filters:
      ret[f] = []
      field = getField(kls._meta.fields, f)
      rel_class = field.related.parent_model
      for o in rel_class.objects.all():
        ret[f].append({
          'id': o.id,
          'title': unicode(o)
        })  
    return ret

  
  @classmethod
  def get_list(kls, data):
    options = {
      'page_no': 1,
      'list_size': 8,
      'search': '',
      'sort': [],
      'range': [0,50]
    }
    options.update(data)
    ret = []
    page_no = options['page_no']
    list_size = options['list_size']
    qset = kls.objects.all()

    search = options['search']
    if search != '':
      qset = kls.fts(qset, search) 
   
    sort = options['sort']
    if sort != []:
      for s in sort:
        if s['operator'] == '-':
          operator = '-'
        else:
          operator = ''
        sort = operator + s['key']
        qset = qset.order_by(sort)
    r0 = options['range'][0]
    r1 = options['range'][1]
    results = qset[r0:r1]
    for r in results:
      ret.append(r.list_dict())
    return ret

def getField(fields, name):
  for f in fields:
    if f.name == name:
      return f
  return False