#
# Copyright SAS Institute
#
#  Licensed under the Apache License, Version 2.0 (the License);
#  you may not use this file except in compliance with the License.
#  You may obtain a copy of the License at
#
#      http://www.apache.org/licenses/LICENSE-2.0
#
#  Unless required by applicable law or agreed to in writing, software
#  distributed under the License is distributed on an "AS IS" BASIS,
#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
#  See the License for the specific language governing permissions and
#  limitations under the License.
#
import http.client as hc
import base64
import json
import os
import ssl
import sys
import urllib
import warnings
import io

import tempfile as tf
from time import sleep

from saspy.sasexceptions import (SASHTTPauthenticateError, SASHTTPconnectionError, SASHTTPsubmissionError)

try:
   import pandas as pd
   import numpy  as np
except ImportError:
   pass

class SASconfigHTTP:
   '''
   This object is not intended to be used directly. Instantiate a SASsession object instead 
   '''
   def __init__(self, session, **kwargs):
      self._kernel   = kwargs.get('kernel', None)   
      SAScfg         = session._sb.sascfg.SAScfg
      self.name      = session._sb.sascfg.name
      cfg            = getattr(SAScfg, self.name)

      self._token    = cfg.get('authtoken', None)
      self.url       = cfg.get('url', '')
      self.ip        = cfg.get('ip', '')
      self.port      = cfg.get('port', None)
      self.ctxname   = cfg.get('context', '')
      self.ctx       = {}
      self.options   = cfg.get('options', [])
      self.ssl       = cfg.get('ssl', True)
      self.verify    = cfg.get('verify', True)
      self.timeout   = cfg.get('timeout', None)
      user           = cfg.get('user', '')
      pw             = cfg.get('pw', '')
      client_id      = cfg.get('client_id', 'SASPy')
      client_secret  = cfg.get('client_secret', '')
      authcode       = cfg.get('authcode', None)
      self.encoding  = cfg.get('encoding', '')
      self.authkey   = cfg.get('authkey', '')
      self._prompt   = session._sb.sascfg._prompt
      self.lrecl     = cfg.get('lrecl', None)

      try:
         self.outopts = getattr(SAScfg, "SAS_output_options")
         self.output  = self.outopts.get('output', 'html5')
      except:
         self.output  = 'html5'

      if self.output.lower() not in ['html', 'html5']:
         print("Invalid value specified for SAS_output_options. Using the default of HTML5")
         self.output  = 'html5'

      # GET Config options
      try:
         self.cfgopts = getattr(SAScfg, "SAS_config_options")
      except:
         self.cfgopts = {}

      lock = self.cfgopts.get('lock_down', True)
      # in lock down mode, don't allow runtime overrides of option values from the config file.

      self.verbose = self.cfgopts.get('verbose', True)
      self.verbose = kwargs.get('verbose', self.verbose)

      inurl = kwargs.get('url', '')             
      if len(inurl) > 0:
         if lock and len(self.url):
            print("Parameter 'url' passed to SAS_session was ignored due to configuration restriction.")
         else:
            self.url = inurl   

      inip = kwargs.get('ip', '')             
      if len(inip) > 0:
         if lock and len(self.ip):
            print("Parameter 'ip' passed to SAS_session was ignored due to configuration restriction.")
         else:
            self.ip = inip   

      inport = kwargs.get('port', None)         
      if inport:
         if lock and self.port:
            print("Parameter 'port' passed to SAS_session was ignored due to configuration restriction.")
         else:
            self.port = inport

      inctxname = kwargs.get('context', '')   
      if len(inctxname) > 0:
         if lock and len(self.ctxname):
            print("Parameter 'context' passed to SAS_session was ignored due to configuration restriction.")
         else:
            self.ctxname = inctxname

      inoptions = kwargs.get('options', [])   
      if len(inoptions) > 0:
         if lock and len(self.options):
           print("Parameter 'options' passed to SAS_session was ignored due to configuration restriction.")
         else:
            self.options = inoptions

      inssl = kwargs.get('ssl', None)         
      if inssl is not None:
         if lock and self.ssl:
            print("Parameter 'ssl' passed to SAS_session was ignored due to configuration restriction.")
         else:
            self.ssl = bool(inssl)

      inver = kwargs.get('verify', None)         
      if inver is not None:
         if lock and self.verify:
            print("Parameter 'verify' passed to SAS_session was ignored due to configuration restriction.")
         else:
            self.verify = bool(inver)

      intout = kwargs.get('timeout', None)
      if intout is not None:
         if lock and self.timeout:
            print("Parameter 'timeout' passed to SAS_session was ignored due to configuration restriction.")
         else:
            self.timeout = intout

      inencoding = kwargs.get('encoding', 'NoOverride')
      if inencoding != 'NoOverride':
         if lock and len(self.encoding):
            print("Parameter 'encoding' passed to SAS_session was ignored due to configuration restriction.")
         else:
            self.encoding = inencoding   
      if not self.encoding or self.encoding != 'utf_8':
         self.encoding = 'utf_8'

      inautht = kwargs.get('authtoken', None)
      if inautht is not None:
         if lock and self._token:
            print("Parameter 'authtoken' passed to SAS_session was ignored due to configuration restriction.")
         else:
            self._token = inautht

      inauthc = kwargs.get('authcode', None)
      if inauthc is not None:
         if lock and authcode:
            print("Parameter 'authcode' passed to SAS_session was ignored due to configuration restriction.")
         else:
            authcode = inauthc

      incis = kwargs.get('client_secret', None)
      if incis is not None:
         if lock and client_secret:
            print("Parameter 'client_secret' passed to SAS_session was ignored due to configuration restriction.")
         else:
            client_secret = incis

      incid = kwargs.get('client_id', None)
      if incid is not None:
         if lock and client_id:
            print("Parameter 'client_id' passed to SAS_session was ignored due to configuration restriction.")
         else:
            client_id = incid

      inlrecl = kwargs.get('lrecl', None)
      if inlrecl is not None:
         if lock and self.lrecl:
            print("Parameter 'lrecl' passed to SAS_session was ignored due to configuration restriction.")
         else:
            self.lrecl = inlrecl
      if not self.lrecl:
         self.lrecl = 1048576

      inak = kwargs.get('authkey', '')
      if len(inak) > 0:
         if lock and len(self.authkey):
            print("Parameter 'authkey' passed to SAS_session was ignored due to configuration restriction.")
         else:
            self.authkey = inak   

      if len(self.url) > 0:
         http = self.url.split('://')
         hp   = http[1].split(':')
         if http[0].lower() in ['http', 'https']:
            self.ip   = hp[0]
            self.port = hp[1] if len(hp) > 1 else self.port
            self.ssl  = True if 's' in http[0].lower() else False
         else:
            print("Parameter 'url' not in recognized format. Expeting 'http[s]://host[:port]'. Ignoring parameter.")

      while len(self.ip) == 0:
         if not lock:
            self.ip = self._prompt("Please enter the host (ip address) you are trying to connect to: ")
            if self.ip is None:
               self._token = None
               raise RuntimeError("No IP address provided.") 
         else:
            print("In lockdown mode and missing ip adress in the config named: "+cfgname )
            raise RuntimeError("No IP address provided.") 

      if not self.port:
         if self.ssl:
            port = 443
         else:
            port = 80

      if not self._token and not authcode:
         found = False
         if self.authkey:
            if os.name == 'nt': 
               pwf = os.path.expanduser('~')+os.sep+'_authinfo'
            else:
               pwf = os.path.expanduser('~')+os.sep+'.authinfo'
            try:
               fid = open(pwf, mode='r')
               for line in fid:
                  if line.startswith(self.authkey): 
                     user = line.partition('user')[2].lstrip().partition(' ')[0].partition('\n')[0]
                     pw   = line.partition('password')[2].lstrip().partition(' ')[0].partition('\n')[0]
                     found = True
                     break
               fid.close()
            except OSError as e:
               print('Error trying to read authinfo file:'+pwf+'\n'+str(e))
               pass
            except:
               pass
      
            if not found:
               print('Did not find key '+self.authkey+' in authinfo file:'+pwf+'\n')
   
         inuser = kwargs.get('user', '')              
         if len(inuser) > 0:
            if lock and len(user):
               print("Parameter 'user' passed to SAS_session was ignored due to configuration restriction.")
            else:
               user = inuser
   
         inpw = kwargs.get('pw', '')                  
         if len(inpw) > 0:
            if lock and len(pw):
               print("Parameter 'pw' passed to SAS_session was ignored due to configuration restriction.")
            else:
               pw = inpw

         code_pw = ''
         if len(user) == 0:
            msg  = "To connect to Viya you need either an authcode or a userid/pw. Neither were provided.\n"
            msg += "Please enter which one you want to enter next. Type one of these now: [authcode | userid]" 
            while code_pw.lower() not in ['userid','authcode']:
               code_pw = self._prompt(msg)
               if code_pw is None:
                  self._token = None
                  raise RuntimeError("Neither authcode nor userid provided.") 

         if code_pw.lower() == 'authcode':
            authcode = self._prompt("Please enter authcode: ")
            if authcode is None:
               self._token = None
               raise RuntimeError("No authcode provided.") 
         else:
            while len(user) == 0:
               user = self._prompt("Please enter userid: ")
               if user is None:
                  self._token = None
                  raise RuntimeError("No userid provided.") 
        
            while len(pw) == 0:
               pw = self._prompt("Please enter password: ", pw = True)
               if pw is None:
                  self._token = None
                  raise RuntimeError("No password provided.") 

      if self.ssl:
         if self.verify:
            # handle having self signed certificate default on Viya w/out copies on client; still ssl, just not verifyable
            try:
               self.HTTPConn = hc.HTTPSConnection(self.ip, self.port, timeout=self.timeout)
               if not self._token:
                  self._token = self._authenticate(user, pw, authcode, client_id, client_secret)
            except ssl.SSLError as e:
               print("SSL certificate verification failed, creating an unverified SSL connection. Error was:"+str(e))
               self.HTTPConn = hc.HTTPSConnection(self.ip, self.port, timeout=self.timeout, context=ssl._create_unverified_context())
               print("You can set 'verify=False' to get rid of this message ")
               if not self._token:
                  self._token   = self._authenticate(user, pw, authcode, client_id, client_secret)
         else:
            self.HTTPConn = hc.HTTPSConnection(self.ip, self.port, timeout=self.timeout, context=ssl._create_unverified_context())
            if not self._token:
               self._token = self._authenticate(user, pw, authcode, client_id, client_secret)
      else:
         self.HTTPConn = hc.HTTPConnection(self.ip, self.port, timeout=self.timeout)
         if not self._token:
            self._token   = self._authenticate(user, pw, authcode, client_id, client_secret)

      if not self._token:
         print("Could not acquire an Authentication Token")
         return

      # GET Contexts 
      contexts = self._get_contexts()
      if contexts == None:
         self._token = None
         raise SASHTTPconnectionError(msg="No Contexts found on Compute Service at ip="+self.ip)

      ctxnames = []
      for i in range(len(contexts)):
         ctxnames.append(contexts[i].get('name'))

      if len(ctxnames) == 0:
         self._token = None
         raise SASHTTPconnectionError(msg="No Contexts found on Compute Service at ip="+self.ip)

      if len(self.ctxname) == 0:
         if len(ctxnames) == 1:
            self.ctxname = ctxnames[0]
            print("Using SAS Context: " + self.ctxname)
         else:
            try:
               ctxname = self._prompt("Please enter the SAS Context you wish to run. Available contexts are: " +
                                      str(ctxnames)+" ")
               if ctxname is None:
                  self._token = None
                  raise RuntimeError("No SAS Context provided.") 
               else:
                  self.ctxname = ctxname
            except:
               raise SASHTTPconnectionError(msg=
                  "SAS Context specified '"+self.ctxname+"' was not found. Prompting failed. Available contexts were: " + 
                   str(ctxnames)+" ")

      while self.ctxname not in ctxnames:
         if not lock:
            '''    this was original code before compute was production. users can't create these on the fly.
            createctx = self._prompt(
                "SAS Context specified was not found. Do you want to create a new context named "+self.ctxname+" [Yes|No]?")
            if createctx.upper() in ('YES', 'Y'):
               contexts = self._create_context(user)
            else:
            '''
            try:
               ctxname = self._prompt(
                   "SAS Context specified was not found. Please enter the SAS Context you wish to run. Available contexts are: " + 
                    str(ctxnames)+" ")
               if ctxname is None:
                  self._token = None
                  raise SASHTTPconnectionError(msg=
                      "SAS Context specified '"+self.ctxname+"' was not found. Prompting failed. Available contexts were: " + 
                       str(ctxnames)+" ")
               else:
                  self.ctxname = ctxname
            except:
               raise SASHTTPconnectionError(msg=
                   "SAS Context specified '"+self.ctxname+"' was not found. Prompting failed. Available contexts were: " + 
                    str(ctxnames)+" ")
         else:
            msg  = "SAS Context specified in the SASconfig ("+self.ctxname+") was not found on this server, and because " 
            msg += "the SASconfig is in lockdown mode, there is no prompting for other contexts. No connection established."
            print(msg)
            self._token = None
            raise RuntimeError("No SAS Context provided.") 

      for i in range(len(contexts)):
         if contexts[i].get('name') == self.ctxname:
            self.ctx = contexts[i]
            break

      if self.ctx == {}:
         raise SASHTTPconnectionError(msg="No context information returned for context {}\n{}".format(self.ctxname, contexts))

      return

   def _authenticate(self, user, pw, authcode, client_id, client_secret):
      #import pdb; pdb.set_trace()
      if authcode:
         uauthcode      = urllib.parse.quote(authcode)
         uclient_id     = urllib.parse.quote(client_id)
         uclient_secret = urllib.parse.quote(client_secret)
         d1 = ("grant_type=authorization_code&code="+uauthcode+"&client_id="+uclient_id+"&client_secret="+uclient_secret).encode(self.encoding)
         headers={"Accept":"application/vnd.sas.compute.session+json","Content-Type":"application/x-www-form-urlencoded"} 
      else:
         uuser = urllib.parse.quote(user)
         upw   = urllib.parse.quote(pw)
         d1 = ("grant_type=password&username="+uuser+"&password="+upw).encode(self.encoding)
         basic = base64.encodebytes("sas.tkmtrb:".encode(self.encoding))
         authheader = '%s' % basic.splitlines()[0].decode(self.encoding)
         headers={"Accept":"application/vnd.sas.compute.session+json","Content-Type":"application/x-www-form-urlencoded",
                  "Authorization":"Basic "+authheader}
      
      # POST AuthToken
      conn = self.HTTPConn; conn.connect()
      try:
         conn.request('POST', "/SASLogon/oauth/token", body=d1, headers=headers)
         req = conn.getresponse()
      except:
         #print("Failure in GET AuthToken. Could not connect to the logon service. Exception info:\n"+str(sys.exc_info()))
         msg="Failure in GET AuthToken. Could not connect to the logon service. Exception info:\n"+str(sys.exc_info())
         raise SASHTTPauthenticateError(msg)
         #return None

      status = req.status
      resp = req.read()
      conn.close()

      if status > 299:
         #print("Failure in GET AuthToken. Status="+str(status)+"\nResponse="+resp.decode(self.encoding))
         msg="Failure in GET AuthToken. Status="+str(status)+"\nResponse="+str(resp)
         raise SASHTTPauthenticateError(msg)
         #return None

      js = json.loads(resp.decode(self.encoding))
      token = js.get('access_token')
      return token

   def _get_contexts(self):
      #import pdb; pdb.set_trace()

      # GET Contexts 
      conn = self.HTTPConn; conn.connect()
      headers={"Accept":"application/vnd.sas.collection+json",
               "Accept-Item":"application/vnd.sas.compute.context.summary+json",
               "Authorization":"Bearer "+self._token}
      conn.request('GET', "/compute/contexts?limit=999999", headers=headers)
      req = conn.getresponse()
      status = req.status
      resp = req.read()
      conn.close()

      if status > 299:
         fmsg = "Failure in GET Contexts. Status="+str(status)+"\nResponse="+resp.decode(self.encoding)
         raise SASHTTPconnectionError(msg=fmsg)

      js = json.loads(resp.decode(self.encoding))
      contexts = js.get('items')

      return contexts

   def _create_context(self, user):
      # GET Contexts 
      conn = self.HTTPConn; conn.connect()
      d1  = '{"name": "SASPy","version": 1,"description": "SASPy Context","attributes": {"sessionInactiveTimeout": 60 },'
      d1 += '"launchContext": {"contextName": "'+self.ctxname+'"},"launchType": "service","authorizedUsers": ["'+user+'"]}'

      headers={"Accept":"application/vnd.sas.compute.context+json",
               "Content-Type":"application/vnd.sas.compute.context.request+json",
               "Authorization":"Bearer "+self._token}
      conn.request('POST', "/compute/contexts", body=d1, headers=headers)
      req = conn.getresponse()
      status = req.status
      resp = req.read()
      conn.close()

      if status > 299:
         print("Failure in POST Context. Status="+str(status)+"\nResponse="+resp.decode(self.encoding))
         return None

      contexts = self._get_contexts()
      return contexts

                   
class SASsessionHTTP():
   '''
   The SASsession object is the main object to instantiate and provides access to the rest of the functionality.
   cfgname   - value in SAS_config_names List of the sascfg.py file
   kernel    - None - internal use when running the SAS_kernel notebook
   user      - userid to use to connect to Compute Service
   pw        - pw for the userid being used to connect to Compute Service
   ip        - overrides IP      Dict entry of cfgname in sascfg.py file
   port      - overrides Port    Dict entry of cfgname in sascfg.py file
   context   - overrides Context Dict entry of cfgname in sascfg.py file 
   options   - overrides Options Dict entry of cfgname in sascfg.py file
   encoding  - This is the python encoding value that matches the SAS session encoding of the Compute Server you are connecting to
   '''
   #def __init__(self, cfgname: str ='', kernel: '<SAS_kernel object>' =None, user: str ='', pw: str ='', 
   #                   ip: str ='', port: int ='', context: str ='', options: list =[]) -> '<SASsession object>':
   def __init__(self, **kwargs):
      self.pid        = None
      self._session   = None
      self._sb        = kwargs.get('sb', None)
      self._log       = "\nNo SAS session established, something must have failed trying to connect\n"
      self.sascfg     = SASconfigHTTP(self, **kwargs)

      if self.sascfg._token:
         self._startsas()
      else:
         None

   def __del__(self):
      if self._session:
         self._endsas()
      self._sb.SASpid = None
      return

   def _startsas(self):
      if self.pid:
         return self.pid

      if len(self.sascfg.options):
         options = '[';
         for opt in self.sascfg.options:
            options += '"'+opt+'", '
         options = (options.rpartition(','))[0]+']'                                
      else:
         options = '[]'

      # POST Session
      uri = None
      for ld in self.sascfg.ctx.get('links'):
         if ld.get('method') == 'POST':
            uri = ld.get('uri')
            break

      if not uri:
         raise SASHTTPconnectionError(msg=
         "POST uri not found in context info. You may not have permission to use this context.\n{}".format(self.sascfg.ctx))

      conn = self.sascfg.HTTPConn; conn.connect()
      d1 = '{"name":"'+self.sascfg.ctxname+'", "description":"saspy session", "version":1, "environment":{"options":'+options+'}}'
      headers={"Accept":"application/vnd.sas.compute.session+json","Content-Type":"application/vnd.sas.compute.session.request+json","Authorization":"Bearer "+self.sascfg._token}

      try:
         conn.request('POST', uri, body=d1, headers=headers)
         req = conn.getresponse()
      except:
         #print("Could not acquire a SAS Session for context: "+self.sascfg.ctxname)
         raise SASHTTPconnectionError(msg="Could not acquire a SAS Session for context: "+self.sascfg.ctxname+". Exception info:\n"+str(sys.exc_info()))
         #return None

      status = req.status
      resp = req.read()
      conn.close()

      if status > 299:
         #print("Failure in POST Session \n"+resp.decode(self.sascfg.encoding))
         #print("Could not acquire a SAS Session for context: "+self.sascfg.ctxname)
         msg="Could not acquire a SAS Session for context: "+self.sascfg.ctxname+". Exception info:\nStatus="+str(status)+"\nResponse="+str(resp)
         raise SASHTTPconnectionError(msg)
         #return None

      self._session = json.loads(resp.decode(self.sascfg.encoding))

      if self._session == None:
         print("Could not acquire a SAS Session for context: "+self.sascfg.ctxname)
         return None
      
      #GET Session uri's once
      for ld in self._session.get('links'):
         if   ld.get('method') == 'GET'     and ld.get('rel') == 'log':
            self._uri_log   = ld.get('uri')
         elif ld.get('method') == 'GET'     and ld.get('rel') == 'listing':
            self._uri_lst   = ld.get('uri')
         elif ld.get('method') == 'GET'     and ld.get('rel') == 'results':
            self._uri_ods   = ld.get('uri')
         elif ld.get('method') == 'GET'     and ld.get('rel') == 'state':
            self._uri_state = ld.get('uri')
         elif ld.get('method') == 'POST'    and ld.get('rel') == 'execute':
            self._uri_exe   = ld.get('uri')
         elif ld.get('method') == 'PUT'     and ld.get('rel') == 'cancel':
            self._uri_can   = ld.get('uri')
         elif ld.get('method') == 'DELETE'  and ld.get('rel') == 'delete':
            self._uri_del   = ld.get('uri')
         elif ld.get('method') == 'GET'     and ld.get('rel') == 'files':
            self._uri_files = ld.get('uri')

      self.pid = self._session.get('id')

      self._log = self._getlog()

      # POST Job - Lets see if the server really came up, cuz you can't tell from what happend so far
      conn = self.sascfg.HTTPConn; conn.connect()
      jcode = json.dumps('\n')
      d1 = '{"code":['+jcode+']}'
      headers={"Accept":"application/json","Content-Type":"application/vnd.sas.compute.job.request+json",
               "Authorization":"Bearer "+self.sascfg._token}
      conn.request('POST', self._uri_exe, body=d1, headers=headers)
      req = conn.getresponse()
      status = req.status
      resp = req.read()
      conn.close()

      try:
         jobid = json.loads(resp.decode(self.sascfg.encoding))
      except:
         jobid = None

      if not jobid or status > 299:
         print("Compute server had issues starting:\n")
         for key in jobid:
            print(key+"="+str(jobid.get(key)))
         return None

      ll = self.submit("options svgtitle='svgtitle'; options validvarname=any validmemname=extend pagesize=max nosyntaxcheck; ods graphics on;", "text")
      if self.sascfg.verbose:
         print("SAS server started using Context "+self.sascfg.ctxname+" with SESSION_ID="+self.pid)       

      return self.pid

   def _endsas(self):
      rc = 0
      if self._session:
         # DELETE Session
         conn = self.sascfg.HTTPConn; conn.connect()
         headers={"Accept":"application/json","Authorization":"Bearer "+self.sascfg._token}
         conn.request('DELETE', self._uri_del, headers=headers)
         req = conn.getresponse()
         resp = req.read()
         conn.close()

         if self.sascfg.verbose:
            print("SAS server terminated for SESSION_ID="+self._session.get('id'))       
         self._session   = None
         self.pid        = None
         self._sb.SASpid = None
      return rc


   def _getlog(self, jobid=None):
      start = 0
      logr = ''

      # GET Log
      if jobid:
         for ld in jobid.get('links'):
            if ld.get('method') == 'GET' and ld.get('rel') == 'log':
               uri = ld.get('uri')
               break
      else:
         uri   = self._uri_log

      while True:
         # GET Log
         conn = self.sascfg.HTTPConn; conn.connect()
         headers={"Accept":"application/vnd.sas.collection+json", "Authorization":"Bearer "+self.sascfg._token}
         conn.request('GET', uri+"?start="+str(start)+"&limit="+str(start+1000), headers=headers)
         req = conn.getresponse()
         status = req.status
         resp = req.read()
         conn.close()

         try:
            js    = json.loads(resp.decode(self.sascfg.encoding))
            log   = js.get('items')
            lines = len(log)
         except:
            lines = None

         if not lines:
            break
         start += lines

         for line in log:
             logr += line.get('line')+'\n'

      if jobid != None:   
         self._log += logr.replace(chr(12), chr(10))

      if logr.count('ERROR:') > 0:
         warnings.warn("Noticed 'ERROR:' in LOG, you ought to take a look and see if there was a problem")
         self._sb.check_error_log = True

      return logr

   def _getlst(self, jobid=None):
      htm = ''
      i   = 0

      # GET the list of results
      if jobid:
         for ld in jobid.get('links'):
            if ld.get('method') == 'GET' and ld.get('rel') == 'results':
               uri = ld.get('uri')+"?includeTypes=ODS"
               break
      else:
         uri = self._uri_lst

      conn = self.sascfg.HTTPConn; conn.connect()
      headers={"Accept":"application/vnd.sas.collection+json", "Authorization":"Bearer "+self.sascfg._token}
      conn.request('GET', uri, headers=headers)
      req = conn.getresponse()
      status = req.status
      resp = req.read()
      conn.close()

      try:
         js = json.loads(resp.decode(self.sascfg.encoding))
         results = js.get('items')
      except:
         results = []

      conn = self.sascfg.HTTPConn; conn.connect()
      headers={"Accept":"application/vnd.sas.collection+json", "Authorization":"Bearer "+self.sascfg._token}
      while i < len(results):
         # GET an ODS Result
         if results[i].get('type') == 'ODS' and len(results[i].get('links')) > 0:
            conn.request('GET', results[i].get('links')[0].get('href'), headers=headers)
            req = conn.getresponse()
            status = req.status
            resp = req.read()
            htm += resp.decode(self.sascfg.encoding)
         i += 1
      conn.close()

      lstd = htm.replace(chr(12), chr(10)).replace('<body class="c body">',
                                                   '<body class="l body">').replace("font-size: x-small;",
                                                                                    "font-size:  normal;")
      return lstd
   
   def _getlsttxt(self, jobid=None):
      start = 0
      lstr = ''
   
      # GET Log
      if jobid:
         for ld in jobid.get('links'):
            if ld.get('method') == 'GET' and ld.get('rel') == 'listing':
               uri = ld.get('uri')
               break
      else:
         uri   = self._uri_lst

      while True:
         conn = self.sascfg.HTTPConn; conn.connect()
         headers={"Accept":"application/vnd.sas.collection+json", "Authorization":"Bearer "+self.sascfg._token}
         conn.request('GET', uri+"?start="+str(start)+"&limit="+str(start+1000), headers=headers)
         req = conn.getresponse()
         status = req.status
         resp = req.read()
         conn.close()

         try:
            js    = json.loads(resp.decode(self.sascfg.encoding))
            lst   = js.get('items')
            lines = len(lst)
         except:
            lines = None

         if not lines:
            break
         start += lines

         for line in lst:
             lstr += line.get('line')+'\n'

      return lstr

   def _asubmit(self, code, results="html"):
      #odsopen  = json.dumps("ods listing close;ods html5 (id=saspy_internal) options(bitmap_mode='inline') device=png; ods graphics on / outputfmt=png;\n")
      #odsopen  = json.dumps("ods listing close;ods html5 (id=saspy_internal) options(bitmap_mode='inline') device=svg; ods graphics on / outputfmt=png;\n")
      #odsclose = json.dumps("ods html5 (id=saspy_internal) close;ods listing;\n")
      odsopen  = json.dumps("ods listing close;ods "+self.sascfg.output+" (id=saspy_internal) options(bitmap_mode='inline') device=svg style="+self._sb.HTML_Style+"; ods graphics on / outputfmt=png;\n")
      odsclose = json.dumps("ods "+self.sascfg.output+" (id=saspy_internal) close;ods listing;\n")
      ods      = True;

      if results.upper() != "HTML":
         ods = False
         odsopen  = '""'
         odsclose = '""'
   
      # POST Job
      conn = self.sascfg.HTTPConn; conn.connect()
      jcode = json.dumps(code)
      d1 = '{"code":['+odsopen+','+jcode+','+odsclose+']}'
      headers={"Accept":"application/json","Content-Type":"application/vnd.sas.compute.job.request+json",
               "Authorization":"Bearer "+self.sascfg._token}
      conn.request('POST', self._uri_exe, body=d1, headers=headers)
      req = conn.getresponse()
      resp = req.read()
      conn.close()

      jobid = json.loads(resp.decode(self.sascfg.encoding))

      return jobid

   def submit(self, code: str, results: str ="html", prompt: dict = None, **kwargs) -> dict:
      '''
      code    - the SAS statements you want to execute 
      results - format of results, HTML is default, TEXT is the alternative
      prompt  - dict of names:flags to prompt for; create marco variables (used in submitted code), then keep or delete
                The keys are the names of the macro variables and the boolean flag is to either hide what you type and delete
                the macros, or show what you type and keep the macros (they will still be available later)
                for example (what you type for pw will not be displayed, user and dsname will):

                results = sas.submit(
                   """
                   libname tera teradata server=teracop1 user=&user pw=&pw;
                   proc print data=tera.&dsname (obs=10); run;
                   """ ,
                   prompt = {'user': False, 'pw': True, 'dsname': False}
                   )

      Returns - a Dict containing two keys:values, [LOG, LST]. LOG is text and LST is 'results' (HTML or TEXT)

      NOTE: to view HTML results in the ipykernel, issue: from IPython.display import HTML  and use HTML() instead of print()
      i.e,: results = sas.submit("data a; x=1; run; proc print;run')
            print(results['LOG'])
            HTML(results['LST']) 
      '''
      prompt  = prompt if prompt is not None else {}
      printto = kwargs.pop('undo', False)

      #odsopen  = json.dumps("ods listing close;ods html5 (id=saspy_internal) options(bitmap_mode='inline') device=png; ods graphics on / outputfmt=png;\n")
      #odsopen  = json.dumps("ods listing close;ods html5 (id=saspy_internal) options(bitmap_mode='inline') device=svg; ods graphics on / outputfmt=png;\n")
      #odsclose = json.dumps("ods html5 (id=saspy_internal) close;ods listing;\n")
      odsopen  = json.dumps("ods listing close;ods "+self.sascfg.output+" (id=saspy_internal) options(bitmap_mode='inline') device=svg style="+self._sb.HTML_Style+"; ods graphics on / outputfmt=png;\n")
      odsclose = json.dumps("ods "+self.sascfg.output+" (id=saspy_internal) close;ods listing;\n")
      ods      = True;
      pcodei   = ''
      pcodeiv  = ''
      pcodeo   = ''

      if self._session == None:
         print("No SAS process attached. SAS process has terminated unexpectedly.")
         return dict(LOG="No SAS process attached. SAS process has terminated unexpectedly.", LST='')

      if results.upper() != "HTML":
         ods = False
         odsopen  = '""'
         odsclose = '""'
   
      if len(prompt):
         pcodei += 'options nosource nonotes;\n'
         pcodeo += 'options nosource nonotes;\n'
         for key in prompt:
            gotit = False
            while not gotit:
               var = self.sascfg._prompt('Please enter value for macro variable '+key+' ', pw=prompt[key])
               if var is None:
                  raise RuntimeError("No value for prompted macro variable provided.") 
               if len(var) > 0:
                  gotit = True
               else:
                  print("Sorry, didn't get a value for that variable.")
            if prompt[key]:
               pcodei  += '%let '+key+'='+var+';\n'
            else:
               pcodeiv += '%let '+key+'='+var+';\n'
            if prompt[key]:
               pcodeo += '%symdel '+key+';\n'
         pcodei += 'options source notes;\n'
         pcodeo += 'options source notes;\n'

      # POST Job
      conn = self.sascfg.HTTPConn; conn.connect()
      jcode = json.dumps(pcodei+pcodeiv+code+'\n'+pcodeo)
      d1 = '{"code":['+odsopen+','+jcode+','+odsclose+']}'
      headers={"Accept":"application/json","Content-Type":"application/vnd.sas.compute.job.request+json",
               "Authorization":"Bearer "+self.sascfg._token}
      conn.request('POST', self._uri_exe, body=d1, headers=headers)
      req = conn.getresponse()
      status = req.status
      resp = req.read()
      conn.close()

      try:
         jobid = json.loads(resp.decode(self.sascfg.encoding))
      except:
         raise SASHTTPsubmissionError(msg="Problem parsing response from Compute Service.\n   Status="+str(status)+"\n   Response="+str(resp))

      if not jobid or status > 299:
         raise SASHTTPsubmissionError(msg="Problem submitting job to Compute Service.\n   Status code="+str(jobid.get('httpStatusCode'))+"\n   Message="+jobid.get('message'))

      for ld in jobid.get('links'):
         if ld.get('method') == 'GET' and ld.get('rel') == 'state':
            uri = ld.get('uri')
            break

      conn    = self.sascfg.HTTPConn;
      headers = {"Accept":"text/plain", "Authorization":"Bearer "+self.sascfg._token}
      done    = False

      delay   = kwargs.get('GETstatusDelay'  , 0.5)
      excpcnt = kwargs.get('GETstatusFailcnt',   5)

      while not done:
         try:
            while True:
               # GET Status for JOB
               conn.connect()
               conn.request('GET', uri, headers=headers)
               req = conn.getresponse()
               resp = req.read()
               conn.close()
               if resp not in [b'running', b'pending']:
                  done = True
                  break
               sleep(delay)

         except (KeyboardInterrupt, SystemExit):
            conn.close()
            print('Exception caught!')
            response = self.sascfg._prompt(
                      "SAS attention handling not yet supported over HTTP. Please enter (Q) to Quit waiting for results or (C) to continue waiting.")
            while True:
               if response is None or response.upper() == 'Q':
                  return dict(LOG='', LST='', BC=True)
               if response.upper() == 'C':
                  break
               response = self.sascfg._prompt("Please enter (Q) to Quit waiting for results or (C) to continue waiting.")

         except hc.RemoteDisconnected as Dis:
            conn.close()
            print('RemoteDisconnected Exception caught!\n'+str(Dis))
            excpcnt -= 1
            if excpcnt < 0:
               raise

      logd = self._getlog(jobid).replace(chr(12), chr(10))

      if ods:
         lstd = self._getlst(jobid).replace(chr(12), chr(10))
      else:
         lstd = self._getlsttxt(jobid).replace(chr(12), chr(10))

      trip = lstd.rpartition("/*]]>*/")
      if len(trip[1]) > 0 and len(trip[2]) < 200:
         lstd = ''

      self._sb._lastlog = logd

      # issue 294
      if printto:
         conn = self.sascfg.HTTPConn; conn.connect()
         jcode = json.dumps('proc printto;run;\n')
         d1 = '{"code":['+jcode+']}'
         headers={"Accept":"application/json","Content-Type":"application/vnd.sas.compute.job.request+json",
                  "Authorization":"Bearer "+self.sascfg._token}
         conn.request('POST', self._uri_exe, body=d1, headers=headers)
         req = conn.getresponse()
         status = req.status
         resp = req.read()
         conn.close()

      if logd.count('ERROR:') > 0:
         warnings.warn("Noticed 'ERROR:' in LOG, you ought to take a look and see if there was a problem")
         self._sb.check_error_log = True

      return dict(LOG=logd, LST=lstd)

   def saslog(self):
      '''
      this method is used to get the current, full contents of the SASLOG
      '''
      return self._log

   def exist(self, table: str, libref: str ="") -> bool:
      '''
      table  - the name of the SAS Data Set
      libref - the libref for the Data Set, defaults to WORK, or USER if assigned

      Returns True it the Data Set exists and False if it does not
      '''
      #can't have an empty libref, so check for user or work
      if not libref:
         # HEAD Libref USER
         conn = self.sascfg.HTTPConn; conn.connect()
         headers={"Accept":"*/*", "Authorization":"Bearer "+self.sascfg._token}
         conn.request('HEAD', "/compute/sessions/"+self.pid+"/data/USER", headers=headers)
         req = conn.getresponse()
         status = req.status
         conn.close()
    
         if status == 200:
            libref = 'USER'
         else:
            libref = 'WORK'

      code  = 'data _null_; e = exist("'
      code += libref+"."
      code += "'"+table.strip()+"'n"+'"'+");\n"
      code += 'v = exist("'
      code += libref+"."
      code += "'"+table.strip()+"'n"+'"'+", 'VIEW');\n if e or v then e = 1;\n"
      code += "te='TABLE_EXISTS='; put te e;run;\n"

      ll = self.submit(code, "text")

      l2 = ll['LOG'].rpartition("TABLE_EXISTS= ")
      l2 = l2[2].partition("\n")
      exists = int(l2[0])

      return bool(exists)
   
      """
      # HEAD Data Table
      conn = self.sascfg.HTTPConn; conn.connect()
      headers={"Accept":"*/*", "Authorization":"Bearer "+self.sascfg._token}
      conn.request('HEAD', "/compute/sessions/"+self.pid+"/data/"+libref+"/"+table, headers=headers)
      req = conn.getresponse()
      status = req.status
      conn.close()

      if status == 200:
         exists = True
      else:
         exists = False
   
      return exists
      """
   
   def read_csv(self, file: str, table: str, libref: str ="", nosub: bool=False, opts: dict ={}) -> '<SASdata object>':
      '''
      This method will import a csv file into a SAS Data Set and return the SASdata object referring to it.
      file    - eithe the OS filesystem path of the file, or HTTP://... for a url accessible file
      table   - the name of the SAS Data Set to create
      libref  - the libref for the SAS Data Set being created. Defaults to WORK, or USER if assigned
      opts    - a dictionary containing any of the following Proc Import options(datarow, delimiter, getnames, guessingrows)
      '''
      code  = "filename x "
   
      if file.lower().startswith("http"):
         code += "url "
   
      code += "\""+file+"\";\n"
      code += "proc import datafile=x out="
      if len(libref):
         code += libref+"."
      code += "'"+table.strip()+"'n dbms=csv replace; "+self._sb._impopts(opts)+" run;"
   
      if nosub:
         print(code)
      else:
         ll = self.submit(code, "text")
   
   def write_csv(self, file: str, table: str, libref: str ="", nosub: bool =False, dsopts: dict ={}, opts: dict ={}) -> 'The LOG showing the results of the step':
      '''
      This method will export a SAS Data Set to a file in CCSV format.
      file    - the OS filesystem path of the file to be created (exported from the SAS Data Set)
      table   - the name of the SAS Data Set you want to export to a CSV file
      libref  - the libref for the SAS Data Set.
      opts    - a dictionary containing any of the following Proc Export options(delimiter, putnames)
      '''
      code  = "filename x \""+file+"\";\n"
      code += "options nosource;\n"
      code += "proc export data="

      if len(libref):
         code += libref+"."

      code += "'"+table.strip()+"'n "+self._sb._dsopts(dsopts)+" outfile=x dbms=csv replace; "
      code += self._sb._expopts(opts)+" run\n;"
      code += "options source;\n"

      if nosub:
         print(code)
      else:
         ll = self.submit(code, "text")
         return ll['LOG']

   def upload(self, localfile: str, remotefile: str, overwrite: bool = True, permission: str = '', **kwargs):
      """
      This method uploads a local file to the SAS servers file system.
      localfile  - path to the local file to upload 
      remotefile - path to remote file to create or overwrite
      overwrite  - overwrite the output file if it exists?
      permission - permissions to set on the new file. See SAS Filename Statement Doc for syntax
      """
      valid = self._sb.file_info(remotefile, quiet = True)

      if valid is None:
         remf = remotefile
      else:
         if valid == {}:
            remf = remotefile + self._sb.hostsep + localfile.rpartition(os.sep)[2]
         else:
            remf = remotefile
            if overwrite == False:
               return {'Success' : False, 
                       'LOG'     : "File "+str(remotefile)+" exists and overwrite was set to False. Upload was stopped."}

      try:
         fd = open(localfile, 'rb')
      except OSError as e:
         return {'Success' : False, 
                 'LOG'     : "File "+str(localfile)+" could not be opened. Error was: "+str(e)}

      fsize = os.path.getsize(localfile)

      if fsize > 0:
         code = "filename _sp_updn '"+remf+"' recfm=N permission='"+permission+"';"
         ll = self.submit(code, 'text')
         logf = ll['LOG']

         # GET Etag
         conn = self.sascfg.HTTPConn; conn.connect()
         headers={"Accept":"application/vnd.sas.compute.fileref+json;application/json",
                  "Authorization":"Bearer "+self.sascfg._token}
         conn.request('GET', self._uri_files+"/_sp_updn", headers=headers)
         req = conn.getresponse()
         status = req.status
         resp = req.read()
         conn.close()

         Etag = req.getheader("Etag")

         # PUT data
         conn = self.sascfg.HTTPConn; conn.connect()
         headers={"Accept":"*/*","Content-Type":"application/octet-stream",
                  "Transfer-Encoding" : "chunked",
                  "Authorization":"Bearer "+self.sascfg._token}

         conn.connect()
         conn.putrequest('PUT', self._uri_files+"/_sp_updn/content")
         conn.putheader("Accept","*/*")
         conn.putheader("Content-Type","application/octet-stream")
         conn.putheader("If-Match",Etag)
         conn.putheader("Transfer-Encoding","chunked")
         conn.putheader("Authorization","Bearer "+self.sascfg._token)
         conn.endheaders()

         blksz = int(kwargs.get('blocksize', 50000))
         while True:
            buf = fd.read1(blksz)
            if len(buf) == 0:
               conn.send(b"0\r\n\r\n")
               break

            lenstr = "%s\r\n" % hex(len(buf))[2:]
            conn.send(lenstr.encode())
            conn.send(buf)
            conn.send(b"\r\n")

         req    = conn.getresponse()
         status = req.status
         resp   = req.read()
         conn.close()

         code = "filename _sp_updn;"
      else:
         logf = ''
         code = """
            filename _sp_updn '"""+remf+"""' recfm=F encoding=binary lrecl=1 permission='"""+permission+"""';
            data _null_;
            fid = fopen('_sp_updn', 'O');
            if fid then
               rc = fclose(fid);
            run;
            filename _sp_updn;
            """

      ll = self.submit(code, 'text')
      logf += ll['LOG']
      fd.close()

      return {'Success' : True, 
              'LOG'     : logf}
 
   def download(self, localfile: str, remotefile: str, overwrite: bool = True, **kwargs):
      """
      This method downloads a remote file from the SAS servers file system.
      localfile  - path to the local file to create or overwrite
      remotefile - path to remote file tp dpwnload
      overwrite  - overwrite the output file if it exists?
      """
      valid = self._sb.file_info(remotefile, quiet = True)

      if valid is None:
         return {'Success' : False, 
                 'LOG'     : "File "+str(remotefile)+" does not exist."}

      if valid == {}:
         return {'Success' : False, 
                 'LOG'     : "File "+str(remotefile)+" is a directory."}

      if os.path.isdir(localfile):
         locf = localfile + os.sep + remotefile.rpartition(self._sb.hostsep)[2]
      else:
         locf = localfile

      try:
         fd = open(locf, 'wb')
         fd.write(b'write can fail even if open worked, as it turns out')
         fd.close()
         fd = open(locf, 'wb')
      except OSError as e:
         return {'Success' : False, 
                 'LOG'     : "File "+str(locf)+" could not be opened or written to. Error was: "+str(e)}

      code = "filename _sp_updn '"+remotefile+"' recfm=F encoding=binary lrecl=4096;"

      ll = self.submit(code, "text")
      logf  = ll['LOG']

      # GET data
      conn = self.sascfg.HTTPConn; conn.connect()
      headers={"Accept":"*/*","Content-Type":"application/octet-stream",
               "Authorization":"Bearer "+self.sascfg._token}
      conn.request('GET', self._uri_files+"/_sp_updn/content", headers=headers)
      req = conn.getresponse()
      status = req.status

      fd.write(req.read())
      fd.flush()
      fd.close()
      conn.close()

      ll = self.submit("filename _sp_updn;", 'text')
      logf += ll['LOG']
      
      return {'Success' : True, 
              'LOG'     : logf}
 
   def _getbytelenF(self, x):
      return len(x.encode(self.sascfg.encoding))

   def _getbytelenR(self, x):
      return len(x.encode(self.sascfg.encoding, errors='replace'))

   def dataframe2sasdata(self, df: '<Pandas Data Frame object>', table: str ='a', 
                         libref: str ="", keep_outer_quotes: bool=False,
                                          embedded_newlines: bool=True,
                         LF: str = '\x01', CR: str = '\x02',
                         colsep: str = '\x03', colrep: str = ' ',
                         datetimes: dict={}, outfmts: dict={}, labels: dict={},
                         outdsopts: dict={}, encode_errors = None, char_lengths = None,
                         **kwargs):
      '''
      This method imports a Pandas Data Frame to a SAS Data Set, returning the SASdata object for the new Data Set.
      df      - Pandas Data Frame to import to a SAS Data Set
      table   - the name of the SAS Data Set to create
      libref  - the libref for the SAS Data Set being created. Defaults to WORK, or USER if assigned
      keep_outer_quotes - for character columns, have SAS keep any outer quotes instead of stripping them off.
      embedded_newlines - if any char columns have embedded CR or LF, set this to True to get them iported into the SAS data set
      LF - if embedded_newlines=True, the chacter to use for LF when transferring the data; defaults to '\x01'
      CR - if embedded_newlines=True, the chacter to use for CR when transferring the data; defaults to '\x02'
      colsep - the column seperator character used for streaming the delimmited data to SAS defaults to '\x03'
      datetimes - dict with column names as keys and values of 'date' or 'time' to create SAS date or times instead of datetimes
      outfmts - dict with column names and SAS formats to assign to the new SAS data set
      labels  - dict with column names and SAS Labels to assign to the new SAS data set
      outdsopts - a dictionary containing output data set options for the table being created
      encode_errors - 'fail' or 'replace' - default is to 'fail', other choice is to 'replace' invalid chars with the replacement char \
                      'ignore' will not  transcode n Python, so you get whatever happens with your data and SAS
      char_lengths - How to determine (and declare) lengths for CHAR variables in the output SAS data set 
      '''
      input   = ""
      xlate   = ""
      card    = ""
      format  = ""
      length  = ""
      label   = ""
      dts     = []
      ncols   = len(df.columns)
      lf      = "'"+'%02x' % ord(LF.encode(self.sascfg.encoding))+"'x"
      cr      = "'"+'%02x' % ord(CR.encode(self.sascfg.encoding))+"'x "
      delim   = "'"+'%02x' % ord(colsep.encode(self.sascfg.encoding))+"'x "
      dtkeys  = datetimes.keys()
      fmtkeys = outfmts.keys()
      labkeys = labels.keys()

      if encode_errors is None:
         encode_errors = 'fail'

      bpc = self._sb.pyenc[0]
      if char_lengths and str(char_lengths).strip() in ['1','2','3','4']:
         bpc = int(char_lengths)
      if char_lengths and str(char_lengths) == 'exact':
         CnotB = False
      else:
         CnotB = bpc == 1

      if type(char_lengths) is not dict:
         charlens = self._sb.df_char_lengths(df, encode_errors, char_lengths)
      else:
         charlens = char_lengths 

      if charlens is None:
         return -1

      charlens = {k.upper():v for k,v in charlens.items()}

      if type(df.index) != pd.RangeIndex:
         warnings.warn("Note that Indexes are not transferred over as columns. Only actual coulmns are transferred")

      for name in df.columns:
         colname = str(name)
         input  += "'"+colname+"'n "
         if colname in labkeys:
            label += "label '"+colname+"'n ="+labels[colname]+";\n"

         if df.dtypes[name].kind in ('O','S','U','V'):
            try:
               length += " '"+colname+"'n $"+str(charlens[colname.upper()])
            except KeyError as e:
               print("Dictionary provided as char_lengths is missing column: "+colname)
               raise e
            if colname in fmtkeys:
               format += "'"+colname+"'n "+outfmts[colname]+" "
            if keep_outer_quotes:
               input  += "~ "
            dts.append('C')
            if embedded_newlines:
               xlate += " '"+colname+"'n = translate('"+colname+"'n, '0A'x, "+lf+");\n"
               xlate += " '"+colname+"'n = translate('"+colname+"'n, '0D'x, "+cr+");\n"
         else:
            if df.dtypes[name].kind in ('M'):
               length += " '"+colname+"'n 8"
               input  += ":B8601DT26.6 "
               if colname not in dtkeys:
                  if colname in fmtkeys:
                     format += "'"+colname+"'n "+outfmts[colname]+" "
                  else:
                     format += "'"+colname+"'n E8601DT26.6 "
               else:
                  if datetimes[colname].lower() == 'date':
                     if colname in fmtkeys:
                        format += "'"+colname+"'n "+outfmts[colname]+" "
                     else:
                        format += "'"+colname+"'n E8601DA. "
                     xlate  += " '"+colname+"'n = datepart('"+colname+"'n);\n"
                  else:
                     if datetimes[colname].lower() == 'time':
                        if colname in fmtkeys:
                           format += "'"+colname+"'n "+outfmts[colname]+" "
                        else:
                           format += "'"+colname+"'n E8601TM. "
                        xlate  += " '"+colname+"'n = timepart('"+colname+"'n);\n"
                     else:
                        print("invalid value for datetimes for column "+colname+". Using default.")
                        if colname in fmtkeys:
                           format += "'"+colname+"'n "+outfmts[colname]+" "
                        else:
                           format += "'"+colname+"'n E8601DT26.6 "
               dts.append('D')
            else:
               length += " '"+colname+"'n 8"
               if colname in fmtkeys:
                  format += "'"+colname+"'n "+outfmts[colname]+" "
               if df.dtypes[name] == 'bool':
                  dts.append('B')
               else:
                  dts.append('N')

      code = "data "
      if len(libref):
         code += libref+"."
      code += "'"+table.strip()+"'n"

      if len(outdsopts):
         code += '('
         for key in outdsopts:
            code += key+'='+str(outdsopts[key]) + ' '
         code += ");\n"
      else:
         code += ";\n"

      if len(length):
         code += "length "+length+";\n"
      if len(format):
         code += "format "+format+";\n"
      code += label
      code += "infile datalines delimiter="+delim+" STOPOVER;\ninput @;\nif _infile_ = '' then delete;\ninput "+input+";\n"+xlate+";\ndatalines4;"
      self._asubmit(code, "text")

      blksz = int(kwargs.get('blocksize', 1000000))
      noencode = self._sb.sascei == 'utf-8' or encode_errors == 'ignore'
      row_num = 0
      code = ""
      for row in df.itertuples(index=False):
         row_num += 1
         card  = ""
         for col in range(ncols):
            var = str(row[col])

            if   dts[col] == 'N' and var == 'nan':
               var = '.'
            elif dts[col] == 'C':
               if var == 'nan' or len(var) == 0:
                  var = ' '
               else:
                  var = var.replace(colsep, colrep)
            elif dts[col] == 'B':
               var = str(int(row[col]))
            elif dts[col] == 'D':
               if var in ['nan', 'NaT', 'NaN']:
                  var = '.'
               else:
                  var = str(row[col].to_datetime64())[:26]

            card += var
            if col < (ncols-1):
               card += colsep

         if embedded_newlines:
            card = card.replace(LF, colrep).replace(CR, colrep)
            card = card.replace('\n', LF).replace('\r', CR)

         code += card+"\n"
 
         if len(code) > blksz:
            if not noencode:
               if encode_errors == 'fail':
                  if CnotB:
                     try:
                        chk = code.encode(self.sascfg.encoding)
                     except Exception as e:
                        self._asubmit(";;;;\n;;;;", "text")
                        ll = self.submit("run;", 'text')
                        print("Transcoding error encountered. Data transfer stopped on or before row "+str(row_num))
                        print("DataFrame contains characters that can't be transcoded into the SAS session encoding.\n"+str(e))
                        return row_num
               else:
                  code = code.encode(self.sascfg.encoding, errors='replace').decode(self.sascfg.encoding)

            self._asubmit(code, "text")
            code = ""

      if not noencode and len(code) > 0:
         if encode_errors == 'fail':
            if CnotB:
               try:
                  code = code.encode(self.sascfg.encoding).decode(self.sascfg.encoding)
               except Exception as e:
                  self._asubmit(";;;;\n;;;;", "text")
                  ll = self.submit("run;", 'text')
                  print("Transcoding error encountered. Data transfer stopped on or before row "+str(row_num))
                  print("DataFrame contains characters that can't be transcoded into the SAS session encoding.\n"+str(e))
                  return row_num
         else:
            code = code.encode(self.sascfg.encoding, errors='replace').decode(self.sascfg.encoding)

      self._asubmit(code+";;;;\n;;;;", "text")
      ll = self.submit("quit;", 'text')
      return None

   def sasdata2dataframe(self, table: str, libref: str ='', dsopts: dict = None,
                         rowsep: str = '\x01', colsep: str = '\x02',
                         rowrep: str = ' ',    colrep: str = ' ',
                         **kwargs) -> '<Pandas Data Frame object>':
      '''
      This method exports the SAS Data Set to a Pandas Data Frame, returning the Data Frame object.
      table   - the name of the SAS Data Set you want to export to a Pandas Data Frame
      libref  - the libref for the SAS Data Set.
      dsopts  - data set options for the input SAS Data Set
      rowsep  - the row seperator character to use; defaults to '\x01'
      colsep  - the column seperator character to use; defaults to '\x02'
      rowrep  - the char to convert to for any embedded rowsep chars, defaults to  ' '
      colrep  - the char to convert to for any embedded colsep chars, defaults to  ' '
      '''
      dsopts = dsopts if dsopts is not None else {}

      method = kwargs.pop('method', None)
      if   method and method.lower() == 'csv':
         return self.sasdata2dataframeCSV(table, libref, dsopts, **kwargs)
      #elif method and method.lower() == 'disk':
      else:
         return self.sasdata2dataframeDISK(table, libref, dsopts, rowsep, colsep,
                                           rowrep, colrep, **kwargs)


   def sasdata2dataframeCSV(self, table: str, libref: str ='', dsopts: dict =None, opts: dict = None, 
                            **kwargs) -> '<Pandas Data Frame object>':
      '''
      This method exports the SAS Data Set to a Pandas Data Frame, returning the Data Frame object.
      table    - the name of the SAS Data Set you want to export to a Pandas Data Frame
      libref   - the libref for the SAS Data Set.
      dsopts   - data set options for the input SAS Data Set
      opts     - a dictionary containing any of the following Proc Export options(delimiter, putnames)
      tempfile - DEPRECATED
      tempkeep - DEPRECATED

      These two options are for advanced usage. They override how saspy imports data. For more info
      see https://sassoftware.github.io/saspy/advanced-topics.html#advanced-sd2df-and-df2sd-techniques
 
      dtype   - this is the parameter to Pandas read_csv, overriding what saspy generates and uses
      my_fmts - bool: if True, overrides the formats saspy would use, using those on the data set or in dsopts=
      '''
      tmp = kwargs.pop('tempfile', None)
      tmp = kwargs.pop('tempkeep', None)

      dsopts = dsopts if dsopts is not None else {}
      opts   = opts   if   opts is not None else {}

      if libref:
         tabname = libref+".'"+table.strip()+"'n "
      else:
         tabname = "'"+table.strip()+"'n "

      code  = "data work.sasdata2dataframe / view=work.sasdata2dataframe; set "+tabname+self._sb._dsopts(dsopts)+";run;\n"

      ll = self.submit(code, "text")

      ##GET Data Table Info
      #conn = self.sascfg.HTTPConn; conn.connect()
      #headers={"Accept":"application/vnd.sas.compute.data.table+json", "Authorization":"Bearer "+self.sascfg._token}
      #conn.request('GET', "/compute/sessions/"+self.pid+"/data/work/sasdata2dataframe", headers=headers)
      #req = conn.getresponse()
      #status = req.status
      #conn.close()

      #resp = req.read()
      #js = json.loads(resp.decode(self.sascfg.encoding))

      conn = self.sascfg.HTTPConn; conn.connect()
      headers={"Accept":"application/vnd.sas.collection+json", "Authorization":"Bearer "+self.sascfg._token}
      conn.request('GET', "/compute/sessions/"+self.pid+"/data/work/sasdata2dataframe/columns?start=0&limit=9999999", headers=headers)
      req = conn.getresponse()
      status = req.status
      resp = req.read()
      conn.close()

      js = json.loads(resp.decode(self.sascfg.encoding))

      varlist = []
      vartype = []
      nvars = js.get('count')
      lst = js.get('items')
      for i in range(len(lst)):
         varlist.append(lst[i].get('name'))
         vartype.append(lst[i].get('type'))

      topts = dict(dsopts)
      topts.pop('firstobs', None)
      topts.pop('obs', None)
   
      code  = "data work._n_u_l_l_;output;run;\n"
      code += "data _null_; set work._n_u_l_l_ "+tabname+self._sb._dsopts(topts)+";put 'FMT_CATS=';\n"
   
      for i in range(nvars):
         code += "_tom = vformatn('"+varlist[i]+"'n);put _tom;\n"
      code += "stop;\nrun;\nproc delete data=work._n_u_l_l_;run;"
   
      ll = self.submit(code, "text")

      l2 = ll['LOG'].rpartition("FMT_CATS=")
      l2 = l2[2].partition("\n")              
      varcat = l2[2].split("\n", nvars)
      del varcat[nvars]

      code  = "proc delete data=work.sasdata2dataframe(memtype=view);run;\n"
      code += "data work.sasdata2dataframe / view=work.sasdata2dataframe; set "+tabname+self._sb._dsopts(dsopts)+";\nformat "

      idx_col = kwargs.pop('index_col', False)
      eng     = kwargs.pop('engine',    'c')
      my_fmts = kwargs.pop('my_fmts',   False)
      k_dts   = kwargs.pop('dtype',     None)
      if k_dts is None and my_fmts:
         print("my_fmts option only valid when dtype= is specified. Ignoring and using necessary formatting for data transfer.")
         my_fmts = False

      if not my_fmts:
         for i in range(nvars):
            if vartype[i] == 'FLOAT':
               code += "'"+varlist[i]+"'n "
               if varcat[i] in self._sb.sas_date_fmts:
                  code += 'E8601DA10. '
               else:
                  if varcat[i] in self._sb.sas_time_fmts:
                     code += 'E8601TM15.6 '
                  else:
                     if varcat[i] in self._sb.sas_datetime_fmts:
                        code += 'E8601DT26.6 '
                     else:
                        code += 'best32. '
      code += ";run;\n"
      ll = self.submit(code, "text")

      if k_dts is None:
         dts = {}
         for i in range(nvars):
            if vartype[i] == 'FLOAT':
               if varcat[i] not in self._sb.sas_date_fmts + self._sb.sas_time_fmts + self._sb.sas_datetime_fmts:
                  dts[varlist[i]] = 'float'
               else:
                  dts[varlist[i]] = 'str'
            else:
               dts[varlist[i]] = 'str'
      else:
         dts = k_dts

      code  = "filename _tomodsx '"+self._sb.workpath+"_tomodsx' lrecl="+str(self.sascfg.lrecl)+" recfm=v  encoding='utf-8';\n"
      code += "proc export data=work.sasdata2dataframe outfile=_tomodsx dbms=csv replace;\n"
      code += self._sb._expopts(opts)+" run;\n"
      code += "proc delete data=work.sasdata2dataframe(memtype=view);run;\n"

      ll = self.submit(code, 'text')
      logf  = ll['LOG']

      code = "filename _sp_updn '"+self._sb.workpath+"_tomodsx' recfm=F encoding=binary lrecl=4096;"

      ll = self.submit(code, "text")
      logf += ll['LOG']

      # GET data
      conn = self.sascfg.HTTPConn; conn.connect()
      headers={"Accept":"*/*","Content-Type":"application/octet-stream",
               "Authorization":"Bearer "+self.sascfg._token}
      conn.request('GET', self._uri_files+"/_sp_updn/content", headers=headers)
      req = conn.getresponse()
      status = req.status

      sockout = _read_sock(req=req)

      df = pd.read_csv(sockout, index_col=idx_col, encoding='utf8', engine=eng, dtype=dts, **kwargs)

      conn.close()

      if k_dts is None:  # don't override these if user provided their own dtypes
         for i in range(nvars):
            if vartype[i] == 'FLOAT':
               if varcat[i] in self._sb.sas_date_fmts + self._sb.sas_time_fmts + self._sb.sas_datetime_fmts:
                  df[varlist[i]] = pd.to_datetime(df[varlist[i]], errors='coerce')

      ll = self.submit("filename _sp_updn;", 'text')
      logf += ll['LOG']

      return df

   def sasdata2dataframeDISK(self, table: str, libref: str ='', dsopts: dict = None,
                             rowsep: str = '\x01', colsep: str = '\x02',
                             rowrep: str = ' ',    colrep: str = ' ', **kwargs) -> '<Pandas Data Frame object>':
      '''
      This method exports the SAS Data Set to a Pandas Data Frame, returning the Data Frame object.
      table    - the name of the SAS Data Set you want to export to a Pandas Data Frame
      libref   - the libref for the SAS Data Set.
      dsopts   - data set options for the input SAS Data Set
      rowsep   - the row seperator character to use; defaults to '\x01'
      colsep   - the column seperator character to use; defaults to '\x02'
      rowrep  - the char to convert to for any embedded rowsep chars, defaults to  ' '
      colrep  - the char to convert to for any embedded colsep chars, defaults to  ' '
      tempfile - DEPRECATED
      tempkeep - DEPRECATED

      These two options are for advanced usage. They override how saspy imports data. For more info
      see https://sassoftware.github.io/saspy/advanced-topics.html#advanced-sd2df-and-df2sd-techniques
 
      dtype   - this is the parameter to Pandas read_csv, overriding what saspy generates and uses
      my_fmts - bool: if True, overrides the formats saspy would use, using those on the data set or in dsopts=
      '''
      tmp = kwargs.pop('tempfile', None)
      tmp = kwargs.pop('tempkeep', None)

      dsopts = dsopts if dsopts is not None else {}

      if libref:
         tabname = libref+".'"+table.strip()+"'n "
      else:
         tabname = "'"+table.strip()+"'n "

      code  = "data work.sasdata2dataframe / view=work.sasdata2dataframe; set "+tabname+self._sb._dsopts(dsopts)+";run;\n"

      ll = self.submit(code, "text")

      ##GET Data Table Info
      #conn = self.sascfg.HTTPConn; conn.connect()
      #headers={"Accept":"application/vnd.sas.compute.data.table+json", "Authorization":"Bearer "+self.sascfg._token}
      #conn.request('GET', "/compute/sessions/"+self.pid+"/data/work/sasdata2dataframe", headers=headers)
      #req = conn.getresponse()
      #status = req.status
      #conn.close()

      #resp = req.read()
      #js = json.loads(resp.decode(self.sascfg.encoding))

      conn = self.sascfg.HTTPConn; conn.connect()
      headers={"Accept":"application/vnd.sas.collection+json", "Authorization":"Bearer "+self.sascfg._token}
      conn.request('GET', "/compute/sessions/"+self.pid+"/data/work/sasdata2dataframe/columns?start=0&limit=9999999", headers=headers)
      req = conn.getresponse()
      status = req.status
      resp = req.read()
      conn.close()

      js = json.loads(resp.decode(self.sascfg.encoding))

      varlist = []
      vartype = []
      nvars = js.get('count')
      lst = js.get('items')
      for i in range(len(lst)):
         varlist.append(lst[i].get('name'))
         vartype.append(lst[i].get('type'))

      topts = dict(dsopts)
      topts.pop('firstobs', None)
      topts.pop('obs', None)
   
      code  = "proc delete data=work.sasdata2dataframe(memtype=view);run;"
      code += "data work._n_u_l_l_;output;run;\n"
      code += "data _null_; set work._n_u_l_l_ "+tabname+self._sb._dsopts(topts)+";put 'FMT_CATS=';\n"
   
      for i in range(nvars):
         code += "_tom = vformatn('"+varlist[i]+"'n);put _tom;\n"
      code += "stop;\nrun;\nproc delete data=work._n_u_l_l_;run;"
   
      ll = self.submit(code, "text")

      l2 = ll['LOG'].rpartition("FMT_CATS=")
      l2 = l2[2].partition("\n")              
      varcat = l2[2].split("\n", nvars)
      del varcat[nvars]

      rdelim = "'"+'%02x' % ord(rowsep.encode(self.sascfg.encoding))+"'x"
      cdelim = "'"+'%02x' % ord(colsep.encode(self.sascfg.encoding))+"'x "

      idx_col = kwargs.pop('index_col', False)
      eng     = kwargs.pop('engine',    'c')
      my_fmts = kwargs.pop('my_fmts',   False)
      k_dts   = kwargs.pop('dtype',     None)
      if k_dts is None and my_fmts:
         print("my_fmts option only valid when dtype= is specified. Ignoring and using necessary formatting for data transfer.")
         my_fmts = False

      code  = "filename _tomodsx '"+self._sb.workpath+"_tomodsx' recfm=v termstr=NL encoding='utf-8';\n"
      code += "data _null_; set "+tabname+self._sb._dsopts(dsopts)+";\n"

      if not my_fmts:
         for i in range(nvars):
            if vartype[i] == 'FLOAT':
               code += "format '"+varlist[i]+"'n "
               if varcat[i] in self._sb.sas_date_fmts:
                  code += 'E8601DA10.'
               else:
                  if varcat[i] in self._sb.sas_time_fmts:
                     code += 'E8601TM15.6'
                  else:
                     if varcat[i] in self._sb.sas_datetime_fmts:
                        code += 'E8601DT26.6'
                     else:
                        code += 'best32.'
               code += '; '
               if i % 10 == 0:
                  code +='\n'

      code += "\nfile _tomodsx lrecl="+str(self.sascfg.lrecl)+" dlm="+cdelim+" recfm=v termstr=NL encoding='utf-8';\n"
      for i in range(nvars):
         if vartype[i] != 'FLOAT':
            code += "'"+varlist[i]+"'n = translate('"
            code +=     varlist[i]+"'n, '{}'x, '{}'x); ".format(   \
                        '%02x%02x' %                               \
                        (ord(rowrep.encode(self.sascfg.encoding)), \
                         ord(colrep.encode(self.sascfg.encoding))),
                        '%02x%02x' %                               \
                        (ord(rowsep.encode(self.sascfg.encoding)), \
                         ord(colsep.encode(self.sascfg.encoding))))
            if i % 10 == 0:
               code +='\n'
      code += "\nput "
      for i in range(nvars):
         code += " '"+varlist[i]+"'n "
         if i % 10 == 0:
            code +='\n'
      code += rdelim+";\nrun;"

      ll = self.submit(code, "text")

      if k_dts is None:
         dts = {}
         for i in range(nvars):
            if vartype[i] == 'FLOAT':
               if varcat[i] not in self._sb.sas_date_fmts + self._sb.sas_time_fmts + self._sb.sas_datetime_fmts:
                  dts[varlist[i]] = 'float'
               else:
                  dts[varlist[i]] = 'str'
            else:
               dts[varlist[i]] = 'str'
      else:
         dts = k_dts

      miss = ['.', ' ']

      quoting = kwargs.pop('quoting', 3)

      code = "filename _sp_updn '"+self._sb.workpath+"_tomodsx' recfm=F encoding=binary lrecl=4096;"

      ll = self.submit(code, "text")
      logf  = ll['LOG']

      # GET data
      conn = self.sascfg.HTTPConn; conn.connect()
      headers={"Accept":"*/*","Content-Type":"application/octet-stream",
               "Authorization":"Bearer "+self.sascfg._token}
      conn.request('GET', self._uri_files+"/_sp_updn/content", headers=headers)
      req = conn.getresponse()
      status = req.status


      sockout = _read_sock(req=req, method='DISK', rsep=(colsep+rowsep+'\n').encode(), rowsep=rowsep.encode())

      df = pd.read_csv(sockout, index_col=idx_col, engine=eng, header=None, names=varlist, 
                       sep=colsep, lineterminator=rowsep, dtype=dts, na_values=miss,
                       encoding='utf-8', quoting=quoting, **kwargs)

      conn.close()

      if k_dts is None:  # don't override these if user provided their own dtypes
         for i in range(nvars):
            if vartype[i] == 'FLOAT':
               if varcat[i] in self._sb.sas_date_fmts + self._sb.sas_time_fmts + self._sb.sas_datetime_fmts:
                  df[varlist[i]] = pd.to_datetime(df[varlist[i]], errors='coerce')

      ll = self.submit("filename _sp_updn;", 'text')
      logf += ll['LOG']
      
      return df

class _read_sock(io.StringIO):
   def __init__(self, **kwargs):
      self.req      = kwargs.get('req')
      self.method   = kwargs.get('method', 'CSV')
      self.rowsep   = kwargs.get('rowsep', b'\n')
      self.rsep     = kwargs.get('rsep', self.rowsep)
      self.datar    = b""

   def read(self, size=4096):
      datl    = 0
      size    = max(size, 4096)
      notarow = True

      while datl < size or notarow:
         data = self.req.read(size)
         dl = len(data)
   
         if dl:
            datl       += dl
            self.datar += data
            if notarow:
               notarow = self.datar.count(self.rsep) <= 0
         else:
            if len(self.datar) <= 0:
               return ''
            else:
               break
   
      data        = self.datar.rpartition(self.rsep)
      if self.method == 'DISK':
         datap    = (data[0]+data[1]).replace(self.rsep, self.rowsep)
      else:
         datap    = data[0]+data[1]
      self.datar  = data[2]

      return datap.decode()

