Storage drone

cords = " "
inv = peripheral.wrap("left")
function refuel()
 if turtle.getFuelLevel() < 300 then
 shell.run("goto 2458 233 87")
 sleep(60)
 returnHome(0)
 end
end

function returnHome(units, state)
 shell.run("goto 2457 233 87")
if state == 0 then
print(units)
print(state)
 for i=1, units do
  turtle.select(i)
  turtle.dropDown()
 end
else
  turtle.select(1)
  turtle.dropDown()
end
end

function collect(x, z, y, units, stack)
 turtle.select(1)
 refuel()
 shell.run("goto".." ".. x.." ".. y.." ".." ".. z)
 if stack == 0 then
  for i=1, units do
  turtle.suckUp()
  end
 else
  inv.suckSneakyUp(0,units)
end
 turtle.select(1)
 inv.dropSneakyUp(1,1)
 returnHome(units, stack)
end


rednet.open("right")
while true do
 rednet.send(912, "done")
 senderId, cords, distance = rednet.receive(5) -- Wait for a message
 print(cords)
  if senderId == 912 then
  rednet.send(912, "working")
  cords = textutils.unserialize(cords)
  if tonumber(cords[6]) < 0 then
   cords[6] = tonumber(cords[6]) /-1
   unitStack = 1
  else
   unitStack = 0
  end
   collect(cords[1], cords[2], cords[3], cords[6], unitStack)
end
end