-- simple tree cutter
-- by pegasus@pimpninjas.org
-- thanks to Gopher/#computercraft
-- for the redstone trick
-- thanks to Lyqyd/#computercraft
-- for the os.pullEvent idea

print("this is woodcutter v8")

function cutDownTree()
  if turtle.compare() then return end
  if 0 ~= turtle.getItemCount(1) then
    turtle.dig()
    turtle.place()
  else turtle.dig() end
  for i = 1, 6 do
    turtle.digUp()
    turtle.up()
    turtle.dig()
  end
  for i = 1, 6 do turtle.down() end
end

function wait ()
  rs.setOutput("back", true)
  os.pullEvent("redstone")
  rs.setOutput("back", false)
end

rs.setOutput("front", true)
rs.setOutput("top", true)

turtle.turnRight()
turtle.turnLeft()

while 12 < turtle.getFuelLevel() do
  if redstone.getInput("front") then
    cutDownTree()
  end
  wait()
end