ccraft treecut

-- Cutting starts by facing middle of the tree

-- Turtle facing rotations
--   0
-- 1   3
--   2

x = 1
y = 1
z = 0
rot = 0

function cut()
  local fuelDelay = 260
  -- rot 0:+Z, 1:+X, 2:-Z
  local ix = 1
  local oldix = ix
  local sx, sz

  fuel(10000, 10000)
  empty()

  -- Map the tree area
  if not turtle.detect() then
    print("Error, no tree in front")
    return
  else
    -- Find Z depth of tree
    repeat
      turtle.dig()
      if turtle.forward() then
        z = z+1
      end
    until not turtle.detect()
    sz = z
    print("Size "..sz.." x "..sz)
    if sz > 1 then
      -- Go back to middle Z
      for i = 1, sz/2 do
        if turtle.back() then
          z = z-1
        end
      end
    end
    turtle.turnRight()
    -- rot = 3
    -- Find X minimum
    while turtle.detect() do
      turtle.dig()
      turtle.forward()
    end
    x = 1
    if sz > 2 then
      -- Go back to middle X
      for i = 1, (sz-1)/2 do
        if turtle.back() then
          x = x+1
        end
      end
    end
    -- Dig to treetop (facing right)
    repeat
      turtle.digUp()
      turtle.up()
      y = y+1
    until (not turtle.detectUp()) and (y > 2)
    print("Height "..y)
    -- rot = 3
    -- Go to min X
    while x > 1 do
      turtle.dig()
      if turtle.forward() then
        x = x-1
      end
    end
    turtle.turnRight()
    -- rot = 2
    -- Go to min Z
    while z > 1 do
      turtle.dig()
      if turtle.forward() then
        z = z-1
      end
    end
    turtle.turnRight()
    turtle.turnRight()
    rot = 0
  end
  sx = sz
  turtle.digDown()
  turtle.down()
  y = y-1

  -- Start cutting loop
  sdelay = 0
  while true do
    if sdelay == 0 then sleep(1) end
    sdelay = (sdelay+1) % 10

    oldix = ix
    if rot == 0 then -- Going forward
      if z < sz then
        if dig() then
          z = z+1
        end
      else -- Reached edge
        if ix > 0 then
          turtle.turnLeft()
          rot = 1 -- Left
        else
          turtle.turnRight()
          rot = 3 -- Right
        end
        if ((x >= sx) and (ix == 1)) or
           ((x <= 1) and (ix == -1)) then
          -- Reached horizontal plane corner
          if y <= 1 then
            -- Digging finished
            break
          else
            -- Move down
            for i=1,3 do
              if y > 1 then
                if turtle.detectDown() then
                  if turtle.digDown() then
                    empty()
                  else
                    break
                  end
                end
                y = y-1
                turtle.down()
              end
            end
            ix = -ix
          end
        elseif sx>1 then
          -- dig 1 to side to prepare for next column
          if dig() then
            x = x+ix
          end
        end
        if oldix > 0 then
          turtle.turnLeft()
        else
          turtle.turnRight()
        end
        rot = 2 -- backwards
      end
    elseif rot == 2 then -- Going backwards
      if z > 1 then
        if dig() then
          z = z-1
        end
      else -- Reached edge
        if ix > 0 then
          turtle.turnRight()
          rot = 1
        else
          turtle.turnLeft()
          rot = 3
        end
        if ((x >= sx) and (ix == 1)) or
           ((x <= 1) and (ix == -1)) then
          -- Reached horizontal plane corner
          if y <= 1 then
            -- Digging finished
            break
          else
            -- Move down
            for i=1,3 do
              if y > 1 then
                if turtle.detectDown() then
                  if turtle.digDown() then
                    empty()
                  else
                    break
                  end
                end
                y = y-1
                turtle.down()
              end
            end
            ix = -ix
          end
        elseif sx>1 then
          -- dig 1 to side to prepare for next column
          if dig() then
            x = x+ix
          end
        end
        if oldix > 0 then
          turtle.turnRight()
        else
          turtle.turnLeft()
        end
        rot = 0 -- forwards
      end
    end
    fuelDelay = fuelDelay-1
    if fuelDelay < 0 then
      fuelDelay = 260
      if turtle.getFuelLevel() < 600 then
        fuel(10000, 10000)
      end
    end
  end

  -- Move back to starting position
  local moves = 40
  repeat
    moves = moves-1
  until moveStep(1+sx/2, 1, 0) or (moves < 0)

  -- Finally empty items to chest
  empty()
  print("Cutting trip finished!")
end

function dig()
  local ret
  if turtle.detectUp then
    turtle.digUp()
  end
  if (y > 1) and turtle.detectDown then
    turtle.digDown()
  end
  if turtle.detect() then
    turtle.dig()
  end
  ret = turtle.forward()
  if turtle.detectUp then
    turtle.digUp()
  end
  empty()
  return ret
end

function doEmpty()
  print("Emptying inventory...")
  while turtle.detectUp() do
    if not turtle.digUp() then
      break
    end
  end
  turtle.select(16) -- Select ender chest for placing
  if not turtle.placeUp() then
    print("Error placing ender chest")
    return
  end
  for i=1,14 do
    turtle.select(i)
    turtle.dropUp()
  end
  turtle.select(16)
  turtle.digUp()
  sleep(1)
  print("Emptying finished")
end

function empty()
  if (turtle.getItemCount(13) > 0) or (turtle.getItemCount(14) > 0) then
    doEmpty()
  end
end

function fuel(minfuel, maxfuel)
  empty() -- Make sure slot 14 is empty
  write("Checking fuel...")
  if turtle.getFuelLevel() > minfuel then
    print("Fuel tank already full")
    return
  end
  while turtle.detectUp() do
    if not turtle.digUp() then
      break
    end
  end
  local chest = false
  turtle.select(14)
  while turtle.getFuelLevel() < maxfuel do
    turtle.refuel()
    if not chest then
      turtle.select(15)
      if not turtle.placeUp() then
        print("Error placing ender chest")
        break
      end
      chest = true
      turtle.select(14)
    end
    turtle.suckUp()
    print("Fuel "..turtle.getFuelLevel())
  end
  if chest then
    turtle.select(15)
    turtle.digUp()
  end
  print("Fuel tank filled")
end

function turnTo(newRot)
  function capRot(r)
    if r < -0.5 then
      r = r+4
    elseif r > 3.5 then
      r = r-4
    end
    return r
  end

  if rot ~= newRot then
    if capRot(rot-1) == newRot then
      turtle.turnRight()
    elseif capRot(rot+1) == newRot then
      turtle.turnLeft()
    else
      turtle.turnRight()
      turtle.turnRight()
    end
    rot = newRot
  end
end

function moveStep(toX, toY, toZ)
  toX = math.floor(toX)
  toY = math.floor(toY)
  toZ = math.floor(toZ)
  local dx = math.abs(toX-x)
  local dz = math.abs(toZ-z)
  if (dx > dz+0.5) and (dx > 0.5) then
    if toX > x then
      turnTo(1)
      dx = 1
    else
      turnTo(3)
      dx = -1
    end
    if turtle.detect() then
      turtle.dig()
    end
    if turtle.forward() then
      x = x+dx
    end
  elseif dz > 0.5 then
    if toZ < z then
      turnTo(2)
      dz = -1
    else
      turnTo(0)
      dz = 1
    end
    if turtle.detect() then
      turtle.dig()
    end
    if turtle.forward() then
      z = z+dz
    end
  else
    -- In this script positive Y-axis goes upwards
    if toY > y+0.5 then
      if turtle.detectUp() then
        turtle.digUp()
      end
      if turtle.up() then
        y = y+1
      end
    elseif toY < y-0.5 then
      if turtle.detectDown() then
        turtle.digDown()
      end
      if turtle.down() then
        y = y-1
      end
    end
  end
  return (x == toX) and (y == toY) and (z == toZ)
end

cut()