import Train, time class Segment: def __init__(self, name, nextSegment, endPoint, prevSegment, startPoint, length, maxSpeed, train, segEndIndicator, segStartIndicator, mqttHost): self.name = name # Name of this segment self.nextSegment = nextSegment # TrackSegment object that comes after this self.endPoint = endPoint # Points object that comes before nextSegment self.prevSegment = prevSegment # TrackSegment object that comes before this self.startPoint = startPoint # Points object that comes after prevSegment self.length = length # length of this segment in cm self.maxSpeed = maxSpeed # maximum speed of this segment self.train = train # Train object that is currently located on this segment self.segEndIndicator = segEndIndicator # mqtt topic published by indicator at end of this segment self.segStartIndicator = segStartIndicator # mqtt topic published by indicator at start of this segment self.mqttHost = mqttHost # mqtt host address for publishing if self.train is None: self.segmentClear = True else: self.segmentClear = False # Getters and setters combined ************************************************* def getName(self, name=None): if name is not None: # set nextSegment self.name = name return self.name def getNextSegment(self, nextSegment=None): if nextSegment is not None: # set nextSegment self.nextSegment = nextSegment return self.nextSegment def getEndPoint(self, endPoint=None): if endPoint is not None: # set endPoint self.endPoint = endPoint return self.endPoint def getPrevSegment(self, prevSegment=None): if prevSegment is not None: # set prevSegment self.prevSegment = prevSegment return self.prevSegment def getStartPoint(self, startPoint=None): if startPoint is not None: # set startPoint self.startPoint = startPoint return self.startPoint def getLength(self, length=None): if length is not None: # set length self.length = length return self.length def getMaxSpeed(self, maxSpeed=None): if maxSpeed is not None: # set maxSpeed self.maxSpeed = maxSpeed return self.maxSpeed def getTrain(self): return self.train def setTrain(self, train=None): if train is not None: # if this segment has a train then reject new train if self.getTrain() is not None: return False # set train to this TrackSegment self.train = train print("Train: " + self.train.getName() + " now on segment " + self.name) # if next segment has train then stop train if self.nextSegment.getTrain() is not None: print("Next segment "+self.nextSegment.name+" has a train") print("Stopping train "+self.train.name+" on segment "+self.name) self.train.setSpeed(0) else: # set train speed to segment maxSpeed maintaining direction currentSpeed = self.train.getSpeed() direction = 1 if currentSpeed != 0: direction = self.train.getSpeed()/abs(self.train.getSpeed()) self.train.setSpeed(self.maxSpeed * direction) return True def getSegEndIndicator(self, segEndIndicator=None): if segEndIndicator is not None: # set segEndIndicator to this TrackSegment self.segEndIndicator = segEndIndicator return self.segEndIndicator def getSegStartIndicator(self, segStartIndicator = None): if segStartIndicator is not None: # set segStartIndicator to this TrackSegment self.segStartIndicator = segStartIndicator return self.segStartIndicator # Methods ********************************************************************** def activateSegEndIndicator(self,msg): # msg will be either "open" or "closed" msg = msg.decode('utf-8') if str(msg) == "open": print("segment "+self.name+" received 'open'") # if a train is present and is moving then train is leaving this segment if (self.train is not None): print("there is a train leaving this segment, give train to next segment") if self.nextSegment.setTrain(self.train): print(self.train.name + " passsed to segment "+self.nextSegment.name) self.train = None else: # train was not accepted by nextSegment. print("ERROR: "+self.nextSegment.name + " already has train: "+self.nextSegment.train.name) print("TO-DO: recalling "+self.train.name) # # Stop train # trainDir = self.train.getSpeed() # trainDir = trainDir/abs(trainDir) # self.train.setSpeed(0) # # backup for 1 sec # self.train.setSpeed(80*trainDir) # time.sleep(1) # self.train.setSpeed(0) # # don't call next train # self.segmentClear = False else: print("Segment "+self.name+" does not have a train") # tell previous segment that this segment is clear if this segment has no train if self.train is None: print("telling segment "+self.prevSegment.name + " to send train") self.prevSegment.sendTrain() else: print("Segment "+self.name+" still has train "+self.train.name) def sendTrain(self): print("segment " +self.name+ " sending train") # if there is a train on this segment if self.train is not None: print("segment " +self.name+ " has train " + self.train.getName()) # check if nextSegment is clear if self.nextSegment.getTrain() is None: print("path is clear to send train") # if train is stopped # print(self.train.getName() + " has speed of " +str(self.train.getSpeed())) if self.train.getSpeed() == 0: print("starting "+self.train.getName()) # start train self.train.setSpeed(self.maxSpeed) else: print("segment " +self.name+ " has no train to send") def print(self): # output this segment to terminal print("Track Segment Object") print("Name: " + self.name) if(self.nextSegment is not None): print("Next Seg: "+ self.nextSegment.getName()) else: print("Next Seg: None") if(self.nextSegment is not None): print("Prev Seg: "+ self.prevSegment.getName()) else: print("Prev Seg: None") if(self.endPoint is not None): print("End Points: "+ self.endPoint) else: print("End Points: None") if(self.startPoint is not None): print("Start Points: "+ self.startPoint) else: print("Start Points: None") print("Length: " + str(self.length)) if(self.segEndIndicator is not None): print("Segment end indicator: "+ self.segEndIndicator) else: print("Segment end indicator: None") if(self.segStartIndicator is not None): print("Segment start indicator: "+ self.segStartIndicator) else: print("Segment start indicator: None") if(self.train is not None): self.train.print() else: print("Train: None") print("mqtt Server: " + str(self.mqttHost))