agent

#after launching the program, the agent is teleported to the player
agent.teleport_to_player()

#this varialbe will be overwritten in the function which will let us build the rails up and down in the correct direction
lastDirection = CompassDirection.SOUTH

'''
Project specifications:

slot 1 - rails
slot 2 - powered rails
slot 3 - stone
slot 4 - redstone
'''

def refillBlocks():
    #adding 64 rails in slot 1 to the agent
    agent.set_item(RAIL, 64, 1)
    agent.set_item(POWERED_RAIL, 64, 2)
    agent.set_item(STONE, 64, 3)
    agent.set_item(REDSTONE_BLOCK, 64, 4)


def rollerCoasterBuilding(railAmount, direction, railType):
    #the varialbe storing the current number of built rails, when calling the function we can decide how many rails we want to build
    currentRailAmount = 0
    #function refilling agent's slots with proper blocks so he can keep building
    refillBlocks()
    # creating a global variable in which we will store the last direction of agent
    global lastDirection
    #defining the direction of agent
    if direction == 1:
        currentAgentDirection = CompassDirection.SOUTH
    elif direction == 2:
        currentAgentDirection = CompassDirection.NORTH
    elif direction == 3:
        currentAgentDirection = CompassDirection.EAST
    elif direction == 4:
        currentAgentDirection = CompassDirection.WEST
    #direction 5 - down, 6 - up
    else:
        currentAgentDirection = lastDirection
    #teleporting the agent, we care about his direction which we will modify later
    agent.teleport(agent.get_position(),currentAgentDirection)
    #when moving, agent will place blocks from the selected spot
    agent.set_assist(PLACE_ON_MOVE, True)
    #when moving, agent destroys blocks in his way
    agent.set_assist(DESTROY_OBSTACLES, True)

    #the loop works until the correct amount of rails is built
    while currentRailAmount < railAmount:
        #clearing path before and after the track
        if agent.detect(AgentDetection.BLOCK, UP) or agent.detect(AgentDetection.BLOCK, FORWARD):
            agent.destroy(UP)

        #if the agent detects that he is in the air and there is nothing to build on, he will place stone block
        elif agent.inspect(AgentInspection.BLOCK, DOWN) == 0 or agent.inspect(AgentInspection.BLOCK, DOWN) == 9:
            if railType == 1:
                agent.set_slot(3)
            else:
                agent.set_slot(4)
            agent.place(DOWN)
        else:
            #if there are no obstacles, setting the slot to rails and moving forward.
            if railType == 1:
                agent.set_slot(1)
            else:
                agent.set_slot(2)
            #  building the rail down
            if direction == 5:
                agent.move(FORWARD, 1)
                agent.destroy(UP)
                agent.set_assist(PLACE_ON_MOVE, False)
                agent.move(DOWN, 1)
                agent.set_assist(PLACE_ON_MOVE, True)
                currentRailAmount += 1
            # building the rail up
            elif direction == 6:
                agent.move(FORWARD, 1)
                agent.destroy(UP)
                agent.set_assist(PLACE_ON_MOVE, False)
                agent.move(UP,2)
                agent.destroy(UP)
                agent.move(DOWN,1)
                agent.set_assist(PLACE_ON_MOVE, True)
                currentRailAmount += 1
            else:
                agent.move(FORWARD, 1)
                currentRailAmount += 1

    player.say("building finished!")
player.on_chat("b",rollerCoasterBuilding)