slaves work nicely now

bring

@@ -19,7 +19,7 @@ if message == "ack" then
 
 	print("He returned safely :)")
 elseif message == "empty" then
-	printf("There is no " .. args[1])
+	print("There is no " .. args[1])
 else
 	print("No slave responded for " .. args[1])
 end

slave

@@ -1,24 +1,55 @@
 local args = { ... }
+local threshold = 5
+
+local function count_total()
+	local c = 0
+	for i = 1, 9 do c = c + turtle.getItemCount(i) end
+	return c
+end
+
+local function count_space()
+	local c = 0
+	for i = 1, 9 do c = c + turtle.getItemSpace(i) end
+	return c
+end
 
 rednet.open("right")
 while true do
 	-- we are using wireless to get the distance
 	-- so the master should be aligned with the slaves
-	local id, mess, dist = rednet.receive()
+	local id, mess, dist = rednet.receive(1)
 	if mess == args[1] then
+		if count_total() < threshold then
+			rednet.send(id, "empty")
+		else
 			rednet.send(id, "ack")
+
+			-- Wait for the pipes to be empty (and not leak)
+			rs.setOutput("left", false)
+			sleep(1)
+
+			-- GO!!!
 			turtle.up()
-		for i = 1, dist do turtle.back() end
+			for i = 1, dist do turtle.forward() end
 
 			print("I will leave again in 5 seconds...")
 			sleep(5)
 			print("Bye!")
 
-		for i = 1, dist do turtle.forward() end
+			for i = 1, dist do turtle.back() end
 			turtle.down()
 			rednet.send(id, "return")
+			print("Back home :)")
+		end
+	end
+
+	-- This will power the engine next to the turtle
+	-- We don't want to fill if we're full
+	-- NOTE: we can't use the side of the modem...
+	if count_space() > threshold then
+		rs.setOutput("left", true)
+	else
+		rs.setOutput("left", false)
 	end
 end
 
--- TODO: activate redstone for the buildcraft engine
-