#!/usr/bin/env python

from urllib import urlencode
from urlparse import unquote
from lxml import html
from xpath import extract_text, extract_url

categories = ['general']
search_url = 'http://search.yahoo.com/search?{query}&b={offset}'
results_xpath = '//div[@class="res"]'
url_xpath = './/h3/a/@href'
title_xpath = './/h3/a'
content_xpath = './/div[@class="abstr"]'
suggestion_xpath = '//div[@id="satat"]//a'

paging = True


def parse_url(url_string):
    endings = ['/RS', '/RK']
    endpositions = []
    start = url_string.find('http', url_string.find('/RU=')+1)
    for ending in endings:
        endpos = url_string.rfind(ending)
        if endpos > -1:
            endpositions.append(endpos)
    end = 0
    if len(endpositions) > 0:
        end = min(endpositions)
    return unquote(url_string[start:end])


def request(query, params):
    offset = (params['pageno'] - 1) * 10 + 1
    if params['language'] == 'all':
        language = 'en'
    else:
        language = params['language'].split('_')[0]
    params['url'] = search_url.format(offset=0,
                                      query=urlencode({'p': query}))
    return params

def response(resp):
    results = []
    dom = html.fromstring(resp.text)

    for result in dom.xpath(results_xpath):
        try:
            url = parse_url(extract_url(result.xpath(url_xpath), search_url))
            title = extract_text(result.xpath(title_xpath)[0])
        except:
            continue
        content = extract_text(result.xpath(content_xpath)[0])
        results.append({'url': url, 'title': title, 'content': content})

    if not suggestion_xpath:
        return results

    for suggestion in dom.xpath(suggestion_xpath):
        results.append({'suggestion': extract_text(suggestion)})

    return results 
