import urllib, urllib2
import json
import sys
import webbrowser
import random

## While probably very lazily/badly programmed, hopefully it functions decently.

def yes_no(question):
    "Returns 1 for a positive response and 0 for a negative response"
    s1 = ""
    pos = ('y', 'yes', 'yup', 'affirmative')
    neg = ('n', 'no', 'nope', 'negative')
    responses = pos + neg
    while not s1 in responses:
        s1 = raw_input(question).lower()
        if not s1 in responses:
            print 'Yes or no response, please.',
    if s1 in pos:
        return True
    elif s1 in neg:
        return False

def get_query():
    "Gets a query from the user"
    #default search is 'computational thought'
    query = {'q' : 'computational thought'}
    #checks for argument, else default query
    if 1 < len(sys.argv):
        #previous version only searched first term
        query['q'] = sys.argv[1:]
    else:
        new_search = yes_no('Would you like to enter your own search? ')
        if new_search:
            query['q'] = raw_input("Enter your search term: ")
    search_term = ''.join(query['q'])
    print 'Search results for:', search_term
    return query

def perform_search(query, start):
    "Performs a search given a query and a starting result number"
    referrer = "http://cs.nyu.edu/q/3900610"
    if userip:
        query.update(userip=userip)
    if api_key:
        query.update(key=api_key)
    #performs the search with the query
    url = 'http://ajax.googleapis.com/ajax/services/search/web?v=1.0&start=%(res)s&%(query)s' % \
          {"res": start, "query": urllib.urlencode(query)}
    #requests and processes results
    request = urllib2.Request(url, headers=dict(Referrer=referrer))
    response = urllib2.urlopen(request)
    data = json.load(response)
    results = data['responseData']
    return results

def print_results(results, start):
    "Prints results given a set of results, numbers them according to 'start'"
    print ''
    for r in results:
        start += 1
        print 'Result', start
        #using titleNoFormatting eliminates tags, encode in case of unicode
        print 'Title:', r['titleNoFormatting'].encode('utf-8', 'replace')
        #using unescapedUrl... looks better?
        print 'URL:', r['unescapedUrl']
        #print 'Content:', r['content'].encode('utf-8', 'replace')
        print "----------"
    if start == 0:
        print 'There are no results.'
        return 0
    return start

def collect_url(results):
    "Collects a set of URLs given a set of results"
    urls = []
    for r in results:
        urls.append(r['url'])
    return urls

def open_url(urls, res_num):
    url_open = urls[res_num]
    fp = webbrowser.open(url_open)
    open_again = yes_no('Would you like to open another page? ')
    if not open_again:
        print 'Happy browsing.',
        return False
    return True
    
def open_results(urls, count):
    "Opens a search result if prompted"
    res_raw, res_num = "", -1
    while True:
        if count == 0:
            print 'I must be a bad program.'
            break
        res_raw = raw_input("Type result number to view ('q' to exit, 'l' for random): ").lower()
        if res_raw.isdigit():
            res_num = int(res_raw) - 1
            if 0 <= res_num < count:
                cont = open_url(urls, res_num)
                if not cont:
                    break
            else:
                print 'Out of range.',
        elif res_raw in ('lucky', 'l', 'random', 'r'):
            rand = random.randrange(0, count)
            cont = open_url(urls, rand)
            if not cont:
                break
        elif res_raw in ('q', 'quit'):
            break
        else:
            print 'Invalid input.',

def handle_results(query):
    "Performs search, prints results, and opens results as needed"
    start, count, urls = 0, 0, [] 
    while True:
        try:
            data = perform_search(query, start)
            results = data['results']
        except TypeError:
            if start > 0:
                print 'End of available results.',
            else:
                print 'No results found.', 
            break
        #64 seems to be the maximum amount of results allowed, remove if/else if otherwise
        try:
            total = int(data['cursor']['resultCount'].replace(',', ''))
        except KeyError:
            print 'There are no results.', 
            break
        if count < 64:
            count = total
        else:
            count = 64
        start = print_results(results, start)
        urls += collect_url(results)
        if start > 0 and start < count:
            next_page = yes_no('Would you like more results? ')
            if not next_page:
                break
        else:
            print 'End of available results.',
            break
    if start < count:
        open_results(urls, start)
    else:
        open_results(urls, count)

def handle_search():
    while True:
        query = get_query()
        handle_results(query)
        search_again = yes_no('Would you like to perform a new search? ')
        if not search_again:
            break

#================================================
api_key, userip = None, None
print '\nWelcome to googlesearcher++.'
handle_search()
print 'Thank you for using googlesearcher++.'