OC wood chopper

--[[
Go forward 7 spaces, wait until the saplings are
grown, go to the left and start cutting a 4x4
tree, both at that level and the one above,
then go up two levels and do it again for 5
more times, then come down, plant the 4 saplings,
return teh 7 spaces to the chest, drop the wood
off, pick up enough coal from the furnace in
front to have a full stack in the last slot,
go to the next cest and get another 4 saplings,
and restart the program
]]--

local robot = require("robot")
local c = require("computer")
local o = require("os")
-- wait in seconds for the sapling to grow
local wait = 60
-- height to chop to /2
local height = 6
-- distance from chest to island
local distance = 7
-- total diameter of the tree (width or depth)
local width = 6


-- chop forward
local function forward()
 robot.swing()
 robot.forward()
 robot.swingUp()
end

-- chop a line
local function chopLine(turn)
 for v = 1, width do forward() end
 if turn then
  robot.turnRight() forward() robot.turnRight()
 else
  robot.turnLeft() forward() robot.turnLeft()
 end
end

-- chop down this and the next level of the tree
local function chopLevel()
 local turnRight = true
 for w = 1, width do
  chopLine(turnRight)
  turnRight = not turnRight
 end
 robot.turnLeft()
 for w = 1, width do robot.forward() end
 robot.turnRight()
end


-- Where the main program starts running
while true do

-- move from chest to saplings and wait
robot.select(2)
robot.suckDown(4)
for i = 1, distance do robot.forward() end
robot.select(1)
while not robot.compare(false) do o.sleep(wait) end

-- move into position
robot.back()
robot.back()
robot.turnLeft()
robot.forward()
robot.forward()
robot.turnRight()

-- chop the tree
for i = 1, height do
 chopLevel()
 robot.up()
 robot.swingUp()
 robot.up()
end

-- plant the saplings
robot.turnRight()
robot.forward()
robot.forward()
robot.turnLeft()
robot.forward()
robot.forward()
robot.forward()
while robot.down() do end
robot.up()
robot.select(2)
robot.placeDown()
robot.forward()
robot.placeDown()
robot.turnRight()
robot.forward()
robot.turnRight()
robot.placeDown()
robot.forward()
robot.placeDown()
-- go back to chests
for i = 0, distance do robot.forward() end
robot.down()
for i = 2, 16 do
 robot.select(i)
 robot.dropDown()
end
robot.turnRight()
robot.forward()
robot.turnRight()
while c.maxEnergy()-c.energy() > 200 do
 os.sleep(60)
end
-- point where the program starts over again
end