#!/usr/bin/python2
import cgi, cgitb, os, sys, time, re
from js_check import jsparser
from  js_check import validate
import redis
from hashlib import sha1
from random import random
import MySQLdb
import simplejson as json

#set max interval between requests
MAX_INTERVAL = 30;
REQUEST_LIMIT = 3;
API_NAME = "shaderblaster"

REMOTE_IP = cgi.escape(os.environ["REMOTE_ADDR"])
REDIS = redis.StrictRedis(host='localhost', port=6379, db=0);
NOW = time.time()

def error(message):
  print json.dumps({'ERROR': message });
  sys.exit(1);


def check_limits(api_name, tf_length, limit, ip, now):
   #when should this expire?
   value = REDIS.get("%s_%s" % (ip, api_name))
   if not value:
     # create new timeframe
     new_tf = "%d-%d" % (now , 1) #  tf starts now
   else:
     parts = re.findall(r'[^-]+', value);
     tf_start = int(parts[0]);
     req_count = int(parts[1]);
     reset_time = tf_start + tf_length
     if reset_time < now :
       new_tf = "%d-%d" % (now , 1) 
     else:
       # still in tf, check limits, increase counter
       req_count += 1
       if req_count > limit :
         # return the too many requests error
         return int(reset_time - now)
       else :
         # increase request count
         new_tf = "%d-%d" % (tf_start, req_count);
   redis_key = "%s_%s" % (ip, api_name ) 
   REDIS.set(redis_key, new_tf);
   REDIS.expire(redis_key, MAX_INTERVAL*2) #arbitrary time  longer than other interval
   return False

def strip_querystring(url):
  p = re.compile('^[^\?]*')
  return p.findall(url)[0]

def store_shader_in_db(script, shader_id=False, image_url="",username="",name=""):
  
  conn = MySQLdb.connect(host= "127.0.0.1",
                    user="asdfus",
                    passwd="gTYgT&M6q",
                    db="asdfus")
  x = conn.cursor()
  try:
    if not shader_id:
      x.execute('''INSERT INTO shader_ids(username) values (%s)''' , (username));
      shader_id = conn.insert_id()
      conn.commit()
      
    x.execute("""INSERT INTO shaders (script, image_url, username, name, remote_addr, time, shader_id)  values (%s,%s,%s,%s,%s,%s,%s)""" ,
      (script, image_url, username, name, REMOTE_IP, NOW, shader_id)
      );
    last_id = conn.insert_id()
    conn.commit()
  except Exception as e:
    conn.rollback()
    return False  
  conn.close()
  return last_id


def main():
  #set up cgi
  print 'Content-type: text/html\n\n'
  cgitb.enable()
  limit_test = check_limits(API_NAME, MAX_INTERVAL, REQUEST_LIMIT, REMOTE_IP, NOW)
  if limit_test: return error("You have exceeded the maximum number of requests, try again in %s seconds" % limit_test);
  #form should contain script, shader_id, username, name, image_url
  form = cgi.FieldStorage(keep_blank_values=1)
  if 'script' not in form or not form['script']: 
    error( 'script not found')
  image_url = 'NULL'
  if 'image_url' in form and form['image_url'].value:
    image_url = strip_querystring(form['image_url'].value)
  test = jsparser.parse(form['script'].value)
  test_failure = validate.test_script(test)
  if test_failure:
    error("Cannot save this shader:%s" % test_failure)

  shader_version_id = store_shader_in_db(
    form['script'].value, form['shader_id'].value, 
    image_url, 
    form['username'].value,
    form['name'].value);
  if not shader_version_id:
    error('DB Error')
  else:
    print json.dumps({
      "success":1, 
      "id": shader_version_id
      });

main()
exit(0);