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

import nltk
import locale
import datetime
import cjson
import clt_sentences
import clt_tokens
import clt_tags
import clt_gen

from mod_python import apache
from mod_python import util 

nltk.data.path.append('/home/markus/nltk_data')
x = nltk.pos_tag([])

def handler(req):
    function = ''
    cgi_input = util.FieldStorage(req)
    try:
        function = cgi_input["input"].split('/')[0]
    except:
        return fail(cgi_input,"function is missing",req)
    if cgi_input.has_key("data"):
        data = cgi_input['data'].decode('UTF-8')
        try:
            data = cjson.decode(data)
        except:
            return fail(cgi_input,"invalid input json for <data>",req)
    else:
        return fail(cgi_input,"parameter <data> missing",req)

    try:
        if(function == 'sentences'):
            if isinstance(data, basestring):
                result = clt_sentences.function(data)
            else:
                return fail(cgi_input,'invalid input, string expected',req)

        elif(function == 'tokens'):
            if isinstance(data,list):
                result = clt_tokens.function(data)
            else:
                return fail(cgi_input,'invalid input, string expected',req)

        elif(function == 'tags'):
            if isinstance(data,list):
                result = clt_tags.function(data)
            else:
                return fail(cgi_input,'invalid input, list expected',req)
        else:
            return fail(cgi_input,'unknown function: %s' % function,req)
    except:
        return fail(cgi_input,'unknown error',req)
    return response(cgi_input,result,req)

def fail(cgi_input,message,req):
    result = clt_gen.json_fail(message)
    return response(cgi_input,result,req)        

def response(cgi_input, result, req):
    write_header(req)
    if cgi_input.has_key("callback"):
        callback=cgi_input['callback']
        req.write(callback +'(' + result + ');')            
    else:
        req.write(result)
    return apache.OK

def write_header(req):
    req.headers_out['Cache-Control'] = 'must-revalidate, max-age:86400, s-maxage:86400'
    req.headers_out['Expires'] = get_expire_time()
    req.headers_out['Access-Control-Allow-Origin'] =  '*'
    req.content_type = "application/json;charset=utf-8"
    req.send_http_header()

def get_expire_time():
    locale.setlocale(locale.LC_TIME, 'en_US')
    return datetime.datetime.utcnow().strftime('%a, %d %b %Y 23:59:59 GMT')