#!/usr/bin/python

from __future__ import absolute_import, print_function

from optparse import OptionParser, make_option
import dbus
import dbus.service
import dbus.mainloop.glib
import bluezutils
import time
import os
import logging
import signal
from gi.repository import GLib

AGENT_INTERFACE = 'org.bluez.Agent1'

gadapter = None
gdiscovering = False
gdevices = {}
g_devices_seen = {}

logging.basicConfig(filename='/var/log/bluetooth-agent.log', level=logging.DEBUG, format='%(asctime)s %(message)s')

def bool2str(val, valiftrue, valiffalse):
  if val:
    return valiftrue
  else:
    return valiffalse

def logging_status(msg):
  with open("/var/run/bt_status", "w") as file:
    file.write(msg + "\n")

def connect_device(path, address, properties, forceConnect, typeInput, typeAudio):
  global gdiscovering

  devName = ""
  trusted = False
  connected = False

  # avoid devices without interesting information
  if "Trusted" not in properties:
    return
  if "Connected" not in properties:
    return

  rproperties = {}
  # Get the adapter name and bt mac
  for key, value in properties.items():
    if type(value) is dbus.String:
      value = value.encode('ascii', 'replace')
    rproperties[key] = value

  trusted   = rproperties["Trusted"]
  paired    = rproperties["Paired"]
  devName = getDevName(rproperties)
  shortDevName = getShortDevName(rproperties)
  connected = rproperties["Connected"]

  # skip non input devices
  if "Icon" not in properties:
    logging.info("Skipping device {} (no type)".format(getDevName(rproperties)));
    return

  if not ( (typeInput and properties["Icon"].startswith("input")) or (typeAudio and properties["Icon"].startswith("audio-card")) ):
    logging.info("Skipping device {} because of type {}".format(getDevName(rproperties), properties["Icon"]));
    return

  blacklistAddr, blacklistName = getBlacklistAddrAndName(properties)

  # add device to the seen list
  if blacklistAddr not in g_devices_seen:
    g_devices_seen[blacklistAddr] = { "name": blacklistName }
    updateKnownDevicesList(g_devices_seen)

  # skip blacklisted devices
  if blacklistAddr is not None and isDeviceBlacklisted(blacklistAddr):
    logging.info("Skipping blacklisted device {}".format(blacklistName))
    return

  logging.info("event for " + devName + "(paired=" + bool2str(paired, "paired", "not paired") + ", trusted=" + bool2str(trusted, "trusted", "untrusted") + ", connected=" + bool2str(connected, "connected", "disconnected") + ")")

  # skipping connected devices
  if paired and trusted and connected:
    logging.info("Skipping already connected device {}".format(getDevName(rproperties)));
    return
  
  if not paired:
    if connected == False and gdiscovering:
      doParing(address, devName, shortDevName)
    return

  # now it is paired
  if not trusted and (gdiscovering or forceConnect):
    logging.info("Trusting (" + devName + ")")
    logging_status("Trusting " + shortDevName + "...")
    bluezProps = dbus.Interface(bus.get_object("org.bluez", path), "org.freedesktop.DBus.Properties")
    bluezProps.Set("org.bluez.Device1", "Trusted", True)

  # now it is paired and trusted
  # Connect if Trusted and paired
  if not connected or forceConnect:
    doConnect(address, devName, shortDevName)

def doParing(address, devName, shortDevName):
  logging.info("Pairing... (" + devName + ")")
  logging_status("Pairing " + shortDevName + "...")
  device = bluezutils.find_device(address)
  try:
    device.Pair()
  except Exception as e:
    logging.info("Pairing failed (" + devName + ")")
    logging_status("Pairing failed (" + shortDevName + ")")

def doConnect(address, devName, shortDevName):
  global gadapter
  global gdiscovering
  
  try:
    # discovery stopped during connection to help some devices
    if gdiscovering:
      logging.info("Stop discovery")
      gadapter.StopDiscovery()

    device = bluezutils.find_device(address)
    ntry=5
    while ntry > 0:
      ntry = ntry -1
      try:
        logging.info("Connecting... (" + devName + ")")
        logging_status("Connecting " + shortDevName + "...")
        device.Connect()
        logging.info("Connected successfully (" + devName + ")")
        logging_status("Connected successfully (" + shortDevName + ")")

        if gdiscovering:
          logging.info("Start discovery")
          gadapter.StartDiscovery()
          return
      except dbus.exceptions.DBusException as err:
        logging.info("dbus: " + err.get_dbus_message())
        time.sleep(1)
      except Exception as err:
        logging.info("Connection failed (" + devName + ")")
        time.sleep(1)
    
    logging.info("Connection failed. Give up. (" + devName + ")")
    logging_status("Connection failed. Give up. (" + shortDevName + ")")
    if gdiscovering:
      logging.info("Start discovery")
      gadapter.StartDiscovery()
  except Exception as e:
    if gdiscovering:
      logging.info("Start discovery")
      gadapter.StartDiscovery()
    # don't raise, while startdiscovery doesn't like it
    #raise e

def getDevName(properties):
  #devName = properties["Name"] + " (" + properties["Address"] + ", " + properties["Icon"] + ")"
  #devStatus = "Trusted=" + str(properties["Trusted"]) + ", paired=" + str(properties["Paired"]) + ", connected=" + str(properties["Connected"]), ", blocked=" + str(properties["Blocked"])
  #devTech = "legacyPairing: " + str(properties["LegacyPairing"]) # + ", RSSI: " + properties["RSSI"]

  if "Name" in properties and "Address" in properties and "Icon" in properties:
    return str(properties["Name"]) + " (" + str(properties["Address"]) + ", " + str(properties["Icon"]) + ")"

  if "Name" in properties and "Address" in properties:
    return str(properties["Name"]) + " (" + str(properties["Address"]) + ")"

  if "Name" in properties and "Icon" in properties:
    return str(properties["Name"]) + " (" + str(properties["Icon"]) + ")"

  if "Name" in properties:
    return str(properties["Name"])

  if "Address" in properties and "Icon" in properties:
    return str(properties["Address"]) + " (" + str(properties["Icon"]) + ")"

  if "Address" in properties:
    return str(properties["Address"])

  if "Icon" in properties:
    return str(properties["Icon"])

  return "unknown"

def updateKnownDevicesList(g_devices_seen):
  f = open("/var/run/bluetooth_seen", "w")
  for key in g_devices_seen:
    f.write("{} {}\n".format(key, g_devices_seen[key]["name"]))
  f.close()

def isDeviceBlacklisted(blacklistAddr):
  datafile = "/var/lib/bluetooth/bluetooth_blacklisted"

  # reread the file each time in case somebody changed it
  if not os.path.isfile(datafile):
    return False

  with open(datafile) as file:
    lines = file.readlines()
    for line in lines:
      if line[0:len(blacklistAddr)] == blacklistAddr:
        return True

  return False

def getBlacklistAddrAndName(properties):
  if "Address" not in properties:
    return None
  address = str(properties["Address"])
  name = ""

  if "Name" in properties:
    name = str(properties["Name"])
  elif "Icon" in properties:
    name = str(properties["Icon"])
  else:
    name = "unknown"

  return address, name

def getShortDevName(properties):
  if "Name" in properties:
    return str(properties["Name"])

  if "Address" in properties:
    return str(properties["Address"])

  if "Icon" in properties:
    return str(properties["Icon"])

  return "unknown"

def getBluetoothWantedTypes():
  if not os.path.isfile("/var/run/bt_types"):
    logging.info("no bt_types file")
    return True, True

  btype = ""
  with open("/var/run/bt_types", "r") as file:
    btype = file.read().strip()
    logging.info("bt_type: {}".format(btype))

  if btype == "":
    return True, True
  if btype == "pad":
    return True, False
  if btype == "audio":
    return False, True
  return False, False

def interfaces_added(path, interfaces):
  global gdevices

  if "org.bluez.Device1" not in interfaces:
    return
  if not interfaces["org.bluez.Device1"]:
    return

  properties = interfaces["org.bluez.Device1"]

  if path in gdevices:
    gdevices[path] = merge2dicts(gdevices[path], properties)
  else:
    gdevices[path] = properties

  if "Address" in gdevices[path]:
    typeInput, typeAudio = getBluetoothWantedTypes()
    connect_device(path, properties["Address"], gdevices[path], False, typeInput, typeAudio)

def properties_changed(interface, changed, invalidated, path):
  global gdevices

  if interface != "org.bluez.Device1":
    return

  if path in gdevices:
    gdevices[path] = merge2dicts(gdevices[path], changed)
  else:
    gdevices[path] = changed

  #logging.info("Properties changed:")
  #logging.info(changed)
  #logging.info(invalidated)

  if "Paired" in changed and changed["Paired"] == True:
    # ok, do as in simple-agent, trust and connect
    typeInput, typeAudio = getBluetoothWantedTypes()
    connect_device(path, gdevices[path]["Address"], gdevices[path], True, typeInput, typeAudio)
    return
  
  # ok, it is now connected, what else ?
  if "Connected" in changed and changed["Connected"] == True:
    return

  if "Connected" in changed and changed["Connected"] == False:
    logging.info("Skipping (property Connected changed to False)");
    return

  if "Address" in gdevices[path]:
    typeInput, typeAudio = getBluetoothWantedTypes()
    connect_device(path, gdevices[path]["Address"], gdevices[path], False, typeInput, typeAudio)

def merge2dicts(d1, d2):
  res = d1.copy()
  res.update(d2)
  return res

def user_signal_start_discovery(signum, frame):
  global gdiscovering
  global gadapter

  try:
    if gdiscovering == False:
      gdiscovering = True
      logging.info("Start discovery (signal)")
      gadapter.StartDiscovery()
  except:
    pass

def user_signal_stop_discovery(signum, frame):
  global gdiscovering
  global gadapter

  try:
    if gdiscovering:
      gdiscovering = False
      logging.info("Stop discovery (signal)")
      gadapter.StopDiscovery()
  except:
    pass

class Agent(dbus.service.Object):
  exit_on_release = True

  def set_exit_on_release(self, exit_on_release):
    self.exit_on_release = exit_on_release

  @dbus.service.method(AGENT_INTERFACE, in_signature="", out_signature="")
  def Release(self):
    logging.info("agent: Release")
    if self.exit_on_release:
      mainloop.quit()
  
  @dbus.service.method(AGENT_INTERFACE, in_signature="os", out_signature="")
  def AuthorizeService(self, device, uuid):
    logging.info("agent: AuthorizeService")
    return
  
  @dbus.service.method(AGENT_INTERFACE, in_signature="o", out_signature="s")
  def RequestPinCode(self, device):
    logging.info("RequestPinCode (%s)" % (device))
    return "0000"

  @dbus.service.method(AGENT_INTERFACE, in_signature="o", out_signature="u")
  def RequestPasskey(self, device):
    logging.info("RequestPasskey (%s)" % (device))
    return 0
  
  @dbus.service.method(AGENT_INTERFACE, in_signature="ouq", out_signature="")
  def DisplayPasskey(self, device, passkey, entered):
    logging.info("agent: DisplayPasskey (%s, %06u entered %u)" % (device, passkey, entered))
  
  @dbus.service.method(AGENT_INTERFACE, in_signature="os", out_signature="")
  def DisplayPinCode(self, device, pincode):
    logging.info("agent: DisplayPinCode (%s, %s)" % (device, pincode))
  
  @dbus.service.method(AGENT_INTERFACE, in_signature="ou", out_signature="")
  def RequestConfirmation(self, device, passkey):
    logging.info("agent: RequestConfirmation")
    return
  
  @dbus.service.method(AGENT_INTERFACE, in_signature="o", out_signature="")
  def RequestAuthorization(self, device):
    logging.info("agent: RequestAuthorization")
    return
  
  @dbus.service.method(AGENT_INTERFACE, in_signature="", out_signature="")
  def Cancel(self):
    logging.info("agent: Cancel")

def do_main_loop(dev_id):
  global gadapter

  # adapter
  try:
    adapter = bluezutils.find_adapter(dev_id)
  except:
    # try to find any adapter
    adapter = bluezutils.find_adapter(None)
  logging.info("adapter found")

  gadapter = adapter
  adapters = {}

  om = dbus.Interface(bus.get_object("org.bluez", "/"), "org.freedesktop.DBus.ObjectManager")
  objects = om.GetManagedObjects()
  for path, interfaces in objects.items():
    if "org.bluez.Device1" in interfaces:
      gdevices[path] = interfaces["org.bluez.Device1"]
    if "org.bluez.Adapter1" in interfaces:
      adapters[path] = interfaces["org.bluez.Adapter1"]
  
  adapter_props = adapters[adapter.object_path]
  logging.info(adapter_props["Name"] + "(" + adapter_props["Address"] + "), powered=" + str(adapter_props["Powered"]))

  # power on adapter if needed
  if adapter_props["Powered"] == 0:
    try:
      logging.info("powering on adapter ("+ adapter_props["Address"] +")")
      adapterSetter = dbus.Interface(bus.get_object("org.bluez", adapter.object_path), "org.freedesktop.DBus.Properties")
      adapterSetter.Set("org.bluez.Adapter1", "Powered", True)
    except:
      pass # hum, not nice

  gdiscovering = False

  # events
  # use events while i manage to stop discovery only from the process having started it
  signal.signal(signal.SIGUSR1, user_signal_start_discovery)
  signal.signal(signal.SIGUSR2, user_signal_stop_discovery)
  
  mainloop = GLib.MainLoop()
  mainloop.run()

if __name__ == '__main__':
  # options
  option_list = [ make_option("-i", "--device", action="store", type="string", dest="dev_id") ]
  parser = OptionParser(option_list=option_list)
  (options, args) = parser.parse_args()

  # initialize the seen devices file
  updateKnownDevicesList(g_devices_seen)

  # register dbus
  dbus.mainloop.glib.DBusGMainLoop(set_as_default=True)
  bus = dbus.SystemBus()

  bus.add_signal_receiver(interfaces_added,   dbus_interface = "org.freedesktop.DBus.ObjectManager", signal_name = "InterfacesAdded")
  bus.add_signal_receiver(properties_changed, dbus_interface = "org.freedesktop.DBus.Properties",    signal_name = "PropertiesChanged", arg0 = "org.bluez.Device1", path_keyword = "path")

  # register the agent
  agentpath = "/storage/.cache/agent"
  obj = bus.get_object("org.bluez", "/org/bluez")
  manager = dbus.Interface(obj, "org.bluez.AgentManager1")
  manager.RegisterAgent(agentpath, "NoInputNoOutput")
  manager.RequestDefaultAgent(agentpath)
  agent = Agent(bus, agentpath)
  logging.info("agent registered")

  # run the agent, allows some tries while hardware can take time to initiate
  time.sleep(5)
  try:
    do_main_loop(options.dev_id)
  except Exception as e:
    logging.error("agent fails")
    logging.error(e, exc_info=True)
    raise
  logging.error("agent gave up")