statemachine.py

   1 from libtuer import ThreadFunction, logger, fire_and_forget, fire_and_forget_cmd
   2 from actor import Actor
   3 import os, random, time, threading
   4
   5 # logger.{debug,info,warning,error,critical}
   6
   7 def play_sound (what):
   8         try:
   9                 soundfiles = os.listdir(SOUNDS_DIRECTORY+what)
  10         except FileNotFoundError:
  11                 logger.error("StateMachine: Unable to list sound files in %s" % (SOUNDS_DIRECTORY+what))
  12                 return
  13         soundfile = SOUNDS_DIRECTORY + what + '/' + random.choice(soundfiles)
  14         fire_and_forget_cmd ([SOUNDS_PLAYER,soundfile], "StateMachine: ")
  15
  16 # convert an absolute nervlist to a relative one
  17 def nervlist_abs2rel(nervlist_abs):
  18         nervlist_rel = []
  19         last_t = 0
  20         for (t, f) in nervlist_abs:
  21                 assert t >= last_t
  22                 nervlist_rel.append((t-last_t, f))
  23                 last_t = t
  24         return nervlist_rel
  25
  26 # StateAuf constants
  27 HELLO_PROBABILITY = 0.2
  28
  29 # StateUnlocking constants
  30 OPEN_REPEAT_TIMEOUT = 7
  31 OPEN_REPEAT_NUMBER = 3
  32
  33 # StateLocking constants
  34 CLOSE_REPEAT_TIMEOUT = 7
  35 CLOSE_REPEAT_NUMBER = 3
  36
  37 # StateFallback constants
  38 FALLBACK_LEAVE_DELAY_LOCK = 5 # seconds
  39
  40 # StateAboutToOpen constants
  41 SWITCH_PRAISE_PROBABILITY = 0.5
  42 ABOUTOPEN_NERVLIST = nervlist_abs2rel([(5, lambda : play_sound("flipswitch")), (10, lambda:play_sound("flipswitch")),\
  43         (20, lambda:play_sound("flipswitch")), (30, lambda:play_sound("flipswitch")), (30, lambda:logger.error("Space open but switch not flipped for 30 seconds")),\
  44         (40, lambda:play_sound("flipswitch")), (50, lambda:play_sound("flipswitch")), (60, lambda:play_sound("mail_sent")),
  45         (60, lambda:logger.critical("Space open but switch not flipped for 60 seconds")), (120, lambda:play_sound("mail_sent")),
  46         (10*60, lambda:logger.critical("Space open but switch not flipped for 10 minutes")),
  47         (60*60, lambda:logger.critical("Space open but switch not flipped for one hour"))])
  48
  49 # Timeout we wait after the switch was switched to "Closed", until we assume nobody will open the door and we just lock it
  50 # ALso the time we wait after the door was opend, till we assume something went wrong and start nerving
  51 LEAVE_TIMEOUT = 20
  52
  53 # play_sound constants
  54 SOUNDS_DIRECTORY = "/opt/tuer/sounds/"
  55 SOUNDS_PLAYER = "/usr/bin/mplayer"
  56
  57
  58 class Nerver():
  59         # A little utility class used to run the nervlists. A nervlist is a list of (n, f) tuples where f() is run after n seconds.
  60         # If f returns something, that's also returned by nerv.
  61         def __init__(self, nervlist):
  62                 self.nervlist = list(nervlist)
  63                 self.last_event_time = time.time()
  64
  65         def nerv(self):
  66                 if len(self.nervlist):
  67                         (wait_time, f) = self.nervlist[0]
  68                         now = time.time()
  69                         time_gone = now-self.last_event_time
  70                         # check if the first element is to be triggered
  71                         if time_gone >= wait_time:
  72                                 self.nervlist = self.nervlist[1:] # "pop" the first element, but do not modify original list
  73                                 self.last_event_time = now
  74                                 return f()
  75
  76
  77 class StateMachine():
  78         # commands you can send
  79         CMD_PINS = 0
  80         CMD_BUZZ = 1
  81         CMD_UNLOCK = 2
  82         CMD_WAKEUP = 3
  83         CMD_LAST = 4
  84
  85         class State():
  86                 def __init__(self, state_machine, nervlist = None):
  87                         self.state_machine = state_machine
  88                         self._nerver = None if nervlist is None else Nerver(nervlist)
  89                 def handle_pins_event(self):
  90                         pass # one needn't implement this
  91                 def handle_buzz_event(self,arg): # this shouldn't be overwritten
  92                         self.actor().act(Actor.CMD_BUZZ)
  93                         arg("200 okay: buzz executed")
  94                 def handle_cmd_unlock_event(self,arg):
  95                         if arg is not None:
  96                                 arg("412 Precondition Failed: The current state (%s) cannot handle the UNLOCK command. Try again later." % self.__class__.__name__)
  97                 def handle_wakeup_event(self):
  98                         if self._nerver is not None:
  99                                 return self._nerver.nerv()
 100                 def on_leave(self):
 101                         pass
 102                 def pins(self):
 103                         return self.state_machine.pins
 104                 def old_pins(self):
 105                         return self.state_machine.old_pins
 106                 def actor(self):
 107                         return self.state_machine.actor
 108                 def api(self):
 109                         return self.state_machine.api
 110                 def handle_event(self,ev,arg): # don't override
 111                         if ev == StateMachine.CMD_PINS:
 112                                 return self.handle_pins_event()
 113                         elif ev == StateMachine.CMD_BUZZ:
 114                                 return self.handle_buzz_event(arg)
 115                         elif ev == StateMachine.CMD_UNLOCK:
 116                                 return self.handle_cmd_unlock_event(arg)
 117                         elif ev == StateMachine.CMD_WAKEUP:
 118                                 return self.handle_wakeup_event()
 119                         else:
 120                                 raise Exception("Unknown command number: %d" % ev)
 121
 122         class AbstractNonStartState(State):
 123                 def handle_pins_event(self):
 124                         if self.pins().door_locked != (not self.pins().space_active):
 125                                 self.actor().act(Actor.CMD_RED_ON)
 126                         else:
 127                                 self.actor().act(Actor.CMD_RED_OFF)
 128                         return super().handle_pins_event()
 129
 130         class AbstractLockedState(AbstractNonStartState):
 131                 '''A state with invariant "The space is locked", switching to StateAboutToOpen when the space becomes unlocked'''
 132                 def __init__(self, sm, nervlist = None):
 133                         super().__init__(sm, nervlist)
 134                         self.actor().act(Actor.CMD_GREEN_OFF)
 135                 def handle_pins_event(self):
 136                         if not self.pins().door_locked:
 137                                 logger.info("Door unlocked, space is about to open")
 138                                 return StateMachine.StateAboutToOpen(self.state_machine)
 139                         return super().handle_pins_event()
 140
 141         class AbstractUnlockedState(AbstractNonStartState):
 142                 '''A state with invariant "The space is unlocked", switching to StateZu when the space becomes locked'''
 143                 def __init__(self, sm, nervlist = None):
 144                         super().__init__(sm, nervlist)
 145                         self.actor().act(Actor.CMD_GREEN_ON)
 146                 def handle_pins_event(self):
 147                         if self.pins().door_locked:
 148                                 logger.info("Door locked, closing space")
 149                                 if self.pins().space_active:
 150                                         logger.warning("StateMachine: door manually locked, but space switch is still on - going to StateZu")
 151                                         play_sound("manual_lock")
 152                                 return StateMachine.StateZu(self.state_machine)
 153                         return super().handle_pins_event()
 154
 155         class StateStart(State):
 156                 def __init__(self, sm, nervlist = None, fallback=False):
 157                         super().__init__(sm, nervlist)
 158                         self.fallback = fallback
 159                 def handle_pins_event(self):
 160                         pins = self.pins()
 161                         if not (pins.door_locked is None or pins.door_closed is None or pins.space_active is None or pins.bell_ringing is None):
 162                                 if self.fallback:
 163                                         logger.info("Going to StateFallback because running in fallback mode")
 164                                         return StateMachine.StateFallback(self.state_machine)
 165                                 if pins.door_locked:
 166                                         logger.info("All sensors got a value, switching to a proper state: Space is closed")
 167                                         return StateMachine.StateZu(self.state_machine)
 168                                 else:
 169                                         logger.info("All sensors got a value, switching to a proper state: Space is (about to) open")
 170                                         return StateMachine.StateAboutToOpen(self.state_machine)
 171                         return super().handle_pins_event()
 172
 173         class StateFallback(State):
 174                 def __init__(self, sm, nervlist = None):
 175                         super().__init__(sm, nervlist)
 176                         self._red_state = False
 177                 def handle_pins_event(self):
 178                         pins = self.pins()
 179                         # buzz if open and bell rang
 180                         if pins.space_active and pins.bell_ringing and not self.old_pins().bell_ringing:
 181                                 logger.info("StateFallback: Space switch on and door bell rung => buzzing")
 182                                 self.actor().act(Actor.CMD_BUZZ)
 183                         # set green LED according to space switch
 184                         if pins.space_active:
 185                                 self.actor().act(Actor.CMD_GREEN_ON)
 186                         else:
 187                                 self.actor().act(Actor.CMD_GREEN_OFF)
 188                         # primitive leaving procedure if space switch turned off
 189                         if not pins.space_active and self.old_pins().space_active:
 190                                 def _close_after_time():
 191                                         time.sleep(FALLBACK_LEAVE_DELAY_LOCK)
 192                                         self.actor().act(Actor.CMD_LOCK)
 193                                 fire_and_forget(_close_after_time)
 194                         # not calling superclass because we want to stay in fallback mode
 195                 def handle_wakeup_event(self):
 196                         # blink red LED
 197                         if self._red_state:
 198                                 self.actor().act(Actor.CMD_RED_OFF)
 199                                 self._red_state = False
 200                         else:
 201                                 self.actor().act(Actor.CMD_RED_ON)
 202                                 self._red_state = True
 203                 def handle_cmd_unlock_event(self,arg):
 204                         if arg is not None:
 205                                 arg("298 Fallback Okay: Trying to unlock the door. The System is in fallback mode, success information is not available.")
 206                         self.actor().act(Actor.CMD_UNLOCK)
 207
 208         class StateZu(AbstractLockedState):
 209                 def handle_cmd_unlock_event(self,callback):
 210                         return StateMachine.StateUnlocking(self.state_machine, callback)
 211                 def handle_pins_event(self):
 212                         if not self.old_pins().space_active and self.pins().space_active: # first thing to check: edge detection
 213                                 logger.info("Space toggled to active while it was closed - unlocking the door")
 214                                 return StateMachine.StateUnlocking(self.state_machine)
 215                         return super().handle_pins_event()
 216
 217         class StateUnlocking(AbstractLockedState):
 218                 def __init__(self,sm,callback=None):
 219                         # construct a nervlist
 220                         nervlist = [(OPEN_REPEAT_TIMEOUT, lambda: self.actor().act(Actor.CMD_UNLOCK)) for t in range(OPEN_REPEAT_NUMBER)]
 221                         nervlist += [(OPEN_REPEAT_TIMEOUT, self.could_not_open)]
 222                         super().__init__(sm,nervlist)
 223                         self.callbacks = []
 224                         self.actor().act(Actor.CMD_UNLOCK)
 225                         # enqueue the callback
 226                         self.handle_cmd_unlock_event(callback)
 227                 def notify(self, s, lastMsg):
 228                         for cb in self.callbacks:
 229                                 cb(s, lastMsg)
 230                 def on_leave(self):
 231                         s = "200 okay: door unlocked" if not self.pins().door_locked else ("500 internal server error: Couldn't unlock door with %d tries à %f seconds" % (OPEN_REPEAT_NUMBER,OPEN_REPEAT_TIMEOUT))
 232                         self.notify(s, lastMsg=True)
 233                 def handle_cmd_unlock_event(self,callback):
 234                         if callback is not None:
 235                                 callback("202 processing: Trying to unlock the door", lastMsg=False)
 236                                 self.callbacks.append(callback)
 237                 def could_not_open(self):
 238                         logger.critical("StateMachine: Couldn't open door after %d tries. Going back to StateZu." % OPEN_REPEAT_NUMBER)
 239                         return StateMachine.StateZu(self.state_machine)
 240
 241         class AbstractStateWhereUnlockingIsRedundant(AbstractUnlockedState):
 242                 def handle_cmd_unlock_event(self, callback):
 243                         callback("299 redundant: Space seems to be already open. Still processing your request tough.")
 244                         logger.info("StateMachine: Received UNLOCK command in %s. This should not be necessary." % self.__class__.__name__)
 245                         self.actor().act(Actor.CMD_UNLOCK)
 246
 247         class StateAboutToOpen(AbstractStateWhereUnlockingIsRedundant):
 248                 def __init__(self, sm):
 249                         super().__init__(sm, ABOUTOPEN_NERVLIST)
 250                 def handle_pins_event(self):
 251                         pins = self.pins()
 252                         if pins.space_active:
 253                                 logger.info("Space activated, opening procedure completed")
 254                                 if not self.old_pins().space_active and random.random() <= SWITCH_PRAISE_PROBABILITY:
 255                                         play_sound("success")
 256                                 return StateMachine.StateAuf(self.state_machine)
 257                         return super().handle_pins_event()
 258
 259         class StateAuf(AbstractStateWhereUnlockingIsRedundant):
 260                 def __init__(self,sm):
 261                         nervlist = [(24*60*60, lambda: logger.critical("Space is now open for 24h. Is everything all right?"))]
 262                         super().__init__(sm, nervlist)
 263                         self.last_buzzed = None
 264                         self.api().set_state(True)
 265                 def handle_pins_event(self):
 266                         pins = self.pins()
 267                         if pins.bell_ringing and not self.old_pins().bell_ringing: # first thing to check: edge detection
 268                                 # someone just pressed the bell
 269                                 logger.info("StateMachine: buzzing because of bell ringing in StateAuf")
 270                                 self.actor().act(Actor.CMD_BUZZ)
 271                         if not pins.space_active:
 272                                 logger.info("StateMachine: space switch turned off - starting leaving procedure")
 273                                 return StateMachine.StateAboutToLeave(self.state_machine)
 274                         if not pins.door_closed and self.old_pins().door_closed and random.random() <= HELLO_PROBABILITY:
 275                                 play_sound("hello")
 276                         return super().handle_pins_event()
 277                 def on_leave(self):
 278                         self.api().set_state(False)
 279
 280         class StateLocking(AbstractUnlockedState):
 281                 def __init__(self,sm):
 282                         # construct a nervlist
 283                         nervlist = [(CLOSE_REPEAT_TIMEOUT, lambda: self.actor().act(Actor.CMD_LOCK)) for t in range(CLOSE_REPEAT_NUMBER)]
 284                         nervlist += [(CLOSE_REPEAT_TIMEOUT, self.could_not_close)]
 285                         super().__init__(sm, nervlist)
 286                         if self.pins().door_closed: # this should always be true, but just to be sure...
 287                                 self.actor().act(Actor.CMD_LOCK)
 288                 def handle_pins_event(self):
 289                         pins = self.pins()
 290                         if not pins.door_closed:
 291                                 # TODO play a sound? This shouldn't happen, door was opened while we are locking
 292                                 logger.warning("StateMachine: door manually opened during locking")
 293                                 return StateMachine.StateAboutToOpen(self.state_machine)
 294                         # TODO do anything here if the switch is activated now?
 295                         return super().handle_pins_event()
 296                 def handle_cmd_unlock_event(self,callback):
 297                         callback("409 conflict: The sphinx is currently trying to lock the door. Try again later.")
 298                 def could_not_close(self):
 299                         logger.critical("StateMachine: Couldn't close door after %d tries. Going back to StateAboutToOpen." % CLOSE_REPEAT_NUMBER)
 300                         return StateMachine.StateAboutToOpen(self.state_machine)
 301
 302         class StateAboutToLeave(AbstractUnlockedState):
 303                 def __init__(self, sm):
 304                         nervlist = [(LEAVE_TIMEOUT, lambda: StateMachine.StateLocking(self.state_machine))]
 305                         super().__init__(sm, nervlist)
 306                 def handle_pins_event(self):
 307                         if not self.pins().door_closed:
 308                                 return StateMachine.StateLeaving(self.state_machine)
 309                         if self.pins().space_active:
 310                                 logger.info("Space re-activated, cancelling leaving procedure")
 311                                 return StateMachine.StateAuf(self.state_machine)
 312                         return super().handle_pins_event()
 313
 314         class StateLeaving(AbstractUnlockedState):
 315                 def __init__(self, sm):
 316                         nervlist = [(LEAVE_TIMEOUT, lambda: StateMachine.StateAboutToOpen(self.state_machine))]
 317                         super().__init__(sm, nervlist)
 318                 def handle_pins_event(self):
 319                         if self.pins().door_closed:
 320                                 logger.info("The space was left, locking the door")
 321                                 return StateMachine.StateLocking(self.state_machine)
 322                         if self.pins().space_active:
 323                                 logger.info("Space re-activated, cancelling leaving procedure")
 324                                 return StateMachine.StateAuf(self.state_machine)
 325                         return super().handle_pins_event()
 326
 327         def __init__(self, actor, waker, api, fallback = False):
 328                 self.actor = actor
 329                 self.api = api
 330                 self.callback = ThreadFunction(self._callback, name="StateMachine")
 331                 self.current_state = StateMachine.StateStart(self, fallback=fallback)
 332                 self.pins = None
 333                 self.old_pins = None
 334                 waker.register(lambda: self.callback(StateMachine.CMD_WAKEUP), 1.0) # wake up every second
 335                 # initially, the space is closed
 336                 api.set_state(False)
 337
 338         def stop (self):
 339                 self.callback.stop()
 340
 341         def _callback(self, cmd, arg=None):
 342                 # update pins
 343                 if cmd == StateMachine.CMD_PINS:
 344                         self.pins = arg
 345                 # handle stuff
 346                 newstate = self.current_state.handle_event(cmd,arg) # returns None or an instance of the new state
 347                 self.old_pins = self.pins
 348                 while newstate is not None:
 349                         assert isinstance(newstate, StateMachine.State), "I should get a state"
 350                         self.current_state.on_leave()
 351                         logger.debug("StateMachine: Doing state transition %s -> %s" % (self.current_state.__class__.__name__, newstate.__class__.__name__))
 352                         self.current_state = newstate
 353                         newstate = self.current_state.handle_event(StateMachine.CMD_PINS, self.pins)