#!/usr/bin/python3

from hippotat import *

import twisted.web
import twisted.web.client

import io

client_cs = None

def set_client(ci,cs,pw):
  global client_cs
  global password
  assert(client_cs is None)
  client_cs = cs
  c.client = ci
  c.max_outstanding = cfg.getint(cs, 'max_requests_outstanding')
  c.target_outstanding = cfg.getint(cs, 'target_requests_outstanding')
  password = pw

def process_cfg():
  global url
  global max_requests_outstanding

  process_cfg_common_always()
  process_cfg_server()

  try:
    c.url = cfg.get('server','url')
  except NoOptionError:
    process_cfg_saddrs()
    c.url = c.saddrs[0].url()

  process_cfg_clients(set_client)

  c.routes = cfg.get('virtual','routes')
  c.max_queue_time = cfg.getint(client_cs, 'max_queue_time')
  c.max_batch_up   = cfg.getint(client_cs, 'max_batch_up')
  c.http_timeout   = cfg.getint(client_cs, 'http_timeout')
  c.http_retry     = cfg.getint(client_cs, 'http_retry')

  process_cfg_ipif(client_cs,
                   (('local', 'client'),
                    ('peer',  'server'),
                    ('rnets', 'routes')))

outstanding = { }

def log_outstanding():
  log_debug(DBG.CTRL_DUMP, 'OS %s' % outstanding)

def start_client():
  global queue
  global agent
  queue = PacketQueue('up', c.max_queue_time)
  agent = twisted.web.client.Agent(reactor, connectTimeout = c.http_timeout)

def outbound(packet, saddr, daddr):
  #print('OUT ', saddr, daddr, repr(packet))
  queue.append(packet)
  check_outbound()

class GeneralResponseConsumer(twisted.internet.protocol.Protocol):
  def __init__(self, req, desc):
    self._req = req
    self._desc = desc

  def _log(self, dflag, msg, **kwargs):
    log_debug(dflag, '%s: %s' % (self._desc, msg), idof=self._req, **kwargs)

  def connectionMade(self):
    self._log(DBG.HTTP_CTRL, 'connectionMade')

class ResponseConsumer(GeneralResponseConsumer):
  def __init__(self, req):
    super().__init__(req, 'RC')
    ssddesc = '[%s] %s' % (id(req), self._desc)
    self._ssd = SlipStreamDecoder(ssddesc, queue_inbound)
    self._log(DBG.HTTP_CTRL, '__init__')

  def dataReceived(self, data):
    self._log(DBG.HTTP_CTRL, 'dataReceived', d=data)
    try:
      self._ssd.inputdata(data)
    except Exception as e:
      self._handleexception()

  def connectionLost(self, reason):
    self._log(DBG.HTTP_CTRL, 'connectionLost ' + str(reason))
    if not reason.check(twisted.web.client.ResponseDone):
      self.latefailure()
      return
    try:
      self._ssd.flush()
      req_fin(req)
    except Exception as e:
      self._handleexception()

  def _handleexception(self):
    self._latefailure(traceback.format_exc())

  def _latefailure(self, reason):
    self._log(DBG.HTTP_CTRL, '_asyncFailure ' + str(reason))
    req_err(self._req, reason)

class ErrorResponseConsumer(twisted.internet.protocol.Protocol):
  def __init__(self, req, resp):
    super().__init__(req, 'ERROR-RC')
    self._resp = resp
    self._m = b''
    try:
      self._phrase = resp.phrase.decode('utf-8')
    except Exception:
      self._phrase = repr(resp.phrase)
    self._log(DBG.HTTP_CTRL, '__init__ %d %s' % (resp.code, self._phrase))

  def dataReceived(self, data):
    self._log(DBG.HTTP_CTRL, 'dataReceived ' + repr(data))
    self._m += data

  def connectionLost(self, reason):
    try:
      mbody = self._m.decode('utf-8')
    except Exception:
      mbody = repr(self._m)
    if not reason.check(twisted.web.client.ResponseDone):
      mbody += ' || ' + str(reason)
    req_err(self._req,
            "FAILED %d %s | %s"
            % (self._resp.code, self._phrase, mbody))

def req_ok(req, resp):
  log_debug(DBG.HTTP_CTRL,
            'req_ok %d %s %s' % (resp.code, repr(resp.phrase), str(resp)),
            idof=req)
  if resp.code == 200:
    rc = ResponseConsumer(req)
  else:
    rc = ErrorResponseConsumer(req, resp)

  resp.deliverBody(rc)
  # now rc is responsible for calling req_fin

def req_err(req, err):
  # called when the Deferred fails, or (if it completes),
  # later, by ResponsConsumer or ErrorResponsConsumer
  try:
    log_debug(DBG.HTTP_CTRL, 'req_err ' + str(err), idof=req)
    if isinstance(err, twisted.python.failure.Failure):
      err = err.getTraceback()
    print('[%#x] %s' % (id(req), err), file=sys.stderr)
    if not isinstance(outstanding[req], int):
      raise RuntimeError('[%#x] previously %s' % (id(req), outstanding[req]))
    outstanding[req] = err
    log_outstanding()
    reactor.callLater(c.http_retry, (lambda: req_fin(req)))
  except Exception as e:
    crash(traceback.format_exc() + '\n----- handling -----\n' + err)

def req_fin(req):
  del outstanding[req]
  log_debug(DBG.HTTP_CTRL, 'req_fin OS=%d' % len(outstanding), idof=req)
  check_outbound()

def check_outbound():
  global outstanding

  while True:
    if                          len(outstanding) >= c.max_outstanding   : break
    if not queue.nonempty() and len(outstanding) >= c.target_outstanding: break

    d = b''
    def moredata(s): nonlocal d; d += s
    queue.process((lambda: len(d)),
                  moredata,
                  c.max_batch_up)
    
    d = mime_translate(d)

    crlf = b'\r\n'
    lf   =   b'\n'
    mime = (b'--b'                                        + crlf +
            b'Content-Type: text/plain; charset="utf-8"'  + crlf +
            b'Content-Disposition: form-data; name="m"'   + crlf + crlf +
            str(c.client)             .encode('ascii')    + crlf +
            password                                      + crlf +
            str(c.target_outstanding) .encode('ascii')    + crlf +
          ((
            b'--b'                                        + crlf +
            b'Content-Type: application/octet-stream'     + crlf +
            b'Content-Disposition: form-data; name="d"'   + crlf + crlf +
            d                                             + crlf
           ) if len(d) else b'')                               +
            b'--b--'                                      + crlf)

    #df = open('data.dump.dbg', mode='wb')
    #df.write(mime)
    #df.close()
    # POST -use -c 'multipart/form-data; boundary="b"' http://localhost:8099/ <data.dump.dbg

    log_debug(DBG.HTTP_FULL, 'requesting: ' + str(mime))

    hh = { 'User-Agent': ['hippotat'],
           'Content-Type': ['multipart/form-data; boundary="b"'],
           'Content-Length': [str(len(mime))] }

    bytesreader = io.BytesIO(mime)
    producer = twisted.web.client.FileBodyProducer(bytesreader)

    req = agent.request(b'POST',
                        c.url,
                        twisted.web.client.Headers(hh),
                        producer)

    outstanding[req] = len(d)
    log_debug(DBG.HTTP_CTRL, 'request OS=%d' % len(outstanding), idof=req, d=d)
    req.addTimeout(c.http_timeout, reactor)
    req.addCallback((lambda resp: req_ok(req, resp)))
    req.addErrback((lambda err: req_err(req, err)))

  log_outstanding()

common_startup()
process_cfg()
start_client()
start_ipif(c.ipif_command, outbound)
check_outbound()
common_run()