from django.template import RequestContext
from django.shortcuts import render_to_response
from django.db.models import Q

from apps.blogs.models import Entry

import re


def normalize_query(query_string,
                    findterms=re.compile(r'"([^"]+)"|(\S+)').findall,
                    normspace=re.compile(r'\s{2,}').sub):
    ''' Splits the query string into individual keywords, getting rid of
    unnecessary spaces and grouping quoted words together.'''

    return [normspace(' ', (t[0] or t[1]).strip()) for t in findterms(query_string)]



def get_query(query_string, search_fields):

    query = None #Query to search for every search term

    terms = normalize_query(query_string)
    for term in terms:
        or_query = None # Query to search for a given term in each field
        for field_name in search_fields:
            q = Q(**{"%s__icontains" % field_name: term})
            if or_query is None:
                or_query = q
            else:
                or_query = or_query | q
        if query is None:
            query = or_query
        else: query = query | or_query
    return query

def search(request):
    query_string = ''
    found_entries = None
    if ('terms' in request.GET) and request.GET['terms'].strip():
        query_string = request.GET['terms']

        entry_query = get_query(query_string, ['title', 'body', ])

        found_entries = Entry.live.filter(entry_query).order_by('-pub_date')
    
    return render_to_response('search/search_results.html',
                            { 'query_string': query_string,
                              'found_entries': found_entries },
)




