CC: exercise5_2

-- exercise5_2
--  surround four directions with walls

-- ####### Define a function ########
function placeSomeBlocks(n)
  for i=1,n do
    turtle.forward()  -- move to next position
    turtle.placeDown()  -- put a block in the ground
  end
end

-- 一辺の長さが nagasa の正方形を作る
function makeSquare(nagasa)
  -- たとえば一辺7の正方形ならば、6個設置を4回繰り返す
  for i=1,4 do
    placeSomeBlocks(nagasa - 1)
    turtle.turnRight()
  end
end

-- 天井を作る
function makeCeiling()
  turtle.turnRight()
  turtle.forward()
  turtle.turnLeft()
  turtle.forward()
  makeSquare(5)

  turtle.turnRight()
  turtle.forward()
  turtle.turnLeft()
  turtle.forward()
  makeSquare(3)

  turtle.turnRight()
  turtle.forward()
  turtle.turnLeft()
  turtle.forward()
  turtle.placeDown()
end

-- ###### Main ########
turtle.select(1) -- the usual phrase

turtle.up()  -- move up

-- stack six squares
for ronoji=1,6 do
  -- 1st stage is made with slot 1, 2nd stage is slot 2, ...
  turtle.select(ronoji)

  -- make 4 sides of a square
  makeSquare(7)
  turtle.up()  -- move up
end

turtle.down()
makeCeiling()