Computercraft: farmer

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-- Vrill's farmer v 1.1       --
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function move(n)
 local can_move=true
 local i
 if n<0 then
  n=-n
  for i=1,n do
   can_move=turtle.back()
   while not can_move do
    print("There is a something on my way!")
    sleep(4)
    can_move=turtle.back()
   end
  end
 else
  for i=1,n do
   can_move=turtle.forward()
   while not can_move do
    print("There is a something on my way!")
    sleep(4)
    can_move=turtle.forward()
   end
  end
 end
end

function moveUp(n)
 local can_move=true
 local i
 if n<0 then
  n=-n
  for i=1,n do
   can_move=turtle.down()
   while not can_move do
    print("There is a something on my way!")
    sleep(4)
    can_move=turtle.down()
   end
  end
 else
  for i=1,n do
   can_move=turtle.up()
   while not can_move do
    print("There is a something on my way!")
    sleep(4)
    can_move=turtle.up()
   end
  end
 end
end

function placeDown()
 local cnt=0
 local thesame=false

 if slot<17 then
  cnt=turtle.getItemCount(slot)
 end

 if cnt>1 and slot<17 then
  turtle.placeDown()

 elseif slot<16 then
  slot=slot+1
  turtle.select(slot)
  thesame=turtle.compareTo(1)
  while not thesame and slot<16 do
   slot=slot+1
   turtle.select(slot)
   thesame=turtle.compareTo(1)
  end

  if thesame then
   turtle.placeDown()
  else
   slot=17
  end

 end
end

function moveDigDown(n)
 local i
 for i=1,n do
  turtle.digDown()
  move(1)
 end
end

function movePlaceDown(n)
 local i
 for i=1,n do
  placeDown()
  move(1)
 end
end

function collectAll()
 moveDigDown(3)
 turtle.turnRight()
 moveDigDown(6)
 turtle.turnRight()
 moveDigDown(6)
 turtle.turnRight()
 moveDigDown(6)
 turtle.turnRight()
 moveDigDown(2)
 turtle.turnRight()
 moveDigDown(1)
 turtle.turnLeft()
 moveDigDown(3)
 turtle.turnRight()
 moveDigDown(4)
 turtle.turnRight()
 moveDigDown(4)
 turtle.turnRight()
 moveDigDown(4)
 turtle.turnRight()
 moveDigDown(1)
 turtle.turnRight()
 move(1)
 turtle.turnLeft()
 moveDigDown(2)
 turtle.turnRight()
 moveDigDown(2)
 turtle.turnRight()
 moveDigDown(2)
 turtle.turnRight()
 moveDigDown(2)

 move(2)
 turtle.turnRight()
 move(1)
end

function placeAll()
 movePlaceDown(3)
 turtle.turnRight()
 movePlaceDown(6)
 turtle.turnRight()
 movePlaceDown(6)
 turtle.turnRight()
 movePlaceDown(6)
 turtle.turnRight()
 movePlaceDown(2)
 turtle.turnRight()
 movePlaceDown(1)
 turtle.turnLeft()
 movePlaceDown(3)
 turtle.turnRight()
 movePlaceDown(4)
 turtle.turnRight()
 movePlaceDown(4)
 turtle.turnRight()
 movePlaceDown(4)
 turtle.turnRight()
 movePlaceDown(1)
 turtle.turnRight()
 move(1)
 turtle.turnLeft()
 movePlaceDown(2)
 turtle.turnRight()
 movePlaceDown(2)
 turtle.turnRight()
 movePlaceDown(2)
 turtle.turnRight()
 movePlaceDown(2)

 move(2)
 turtle.turnRight()
 move(1)

 slot=1
end

function dropSeeds()
 local i=1
 local dropcnt=0

 turtle.select(1)
 dropcnt=turtle.getItemCount(1)-1
 turtle.drop(dropcnt)
 for i=2,16 do
  turtle.select(i)
  if turtle.compareTo(1) then
   dropcnt=turtle.getItemCount(i)
   turtle.drop(dropcnt)
  end
 end
 turtle.select(1)
end

function dropAll()
 local i=1
 local dropcnt=0

 for i=2,16 do
  turtle.select(i)
  dropcnt=turtle.getItemCount(i)
  turtle.drop(dropcnt)
 end
 turtle.select(1)
end

function refuelMe()
 local i=2
 local fuelcnt=0

 for i=2,16 do
  turtle.select(i)
  fuelcnt=turtle.getItemCount(i)
  turtle.refuel(fuelcnt)
 end
 turtle.select(1)
end

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--global variables:
slot=1

print("  *Label: ",os.getComputerLabel())
print("  *'Farmer' prog. is active!")
print("  *Fuel Level:",turtle.getFuelLevel())
print("  *Waiting for redstone signal...")

os.pullEvent("redstone")

local flevel=0

refuelMe()
flevel=turtle.getFuelLevel()

if turtle.getItemCount(1)<1 then
 print("I need a seed in slot 1!")

elseif flevel<240 then
 print("Not enough fuel!")

else
 slot=1
 turtle.select(slot)

 move(3)
 turtle.turnLeft()
 moveUp(-1)

 collectAll()
 placeAll()

 turtle.turnLeft()
 moveUp(1)
 move(3)
 turtle.turnLeft()

 dropSeeds()

 turtle.turnLeft()
 turtle.turnLeft()

 dropAll()

 turtle.turnRight()
end
--
--
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shell.run("farmer")
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