sleep(1)

local tArgs = { ... }
if #tArgs ~= 3 then
	print( "Usage: clear_room <length> <width> <height>" )
	return
end

local length = tonumber(tArgs[1])
local width = tonumber(tArgs[2])
local height = tonumber(tArgs[3])
directions = {"north", "east", "south", "west"}

x_pos, y_pos, z_pos, direction = 0, 0, 0, 1

local function turn_to(d)
 while direction ~= d do
  turtle.turnRight()
  direction = (direction % 4) + 1
 end
end

local function go_to_position(x, y, z, d)

 while z_pos ~= z do
  if z_pos > z then
    turtle.down()
    z_pos = z_pos - 1;
  else
    turtle.up()
    z_pos = z_pos + 1;
  end
 end
 
 if x_pos > x then
  turn_to(4)
  while x_pos ~= x do
    turtle.forward()
    x_pos = x_pos - 1;
  end 
 else
  turn_to(2)
  while x_pos ~= x do
    turtle.forward()
    x_pos = x_pos + 1;
  end
 end
 
 if y_pos > y then
  turn_to(3)
  while y_pos ~= y do
    turtle.forward()
    y_pos = y_pos - 1;
  end 
 else
  turn_to(1)
  while y_pos ~= y do
    turtle.forward()
    y_pos = y_pos + 1;
  end
 end
 
 turn_to(d)
end

local function empty_inventory()
  for i = 1, 9 do
    turtle.select(i)
    turtle.drop()
  end
end

local function check_inventory()

  local open_slots = 0
  for i = 1, 9 do
    local number_items = turtle.getItemCount(i)
    if number_items == 0 then
      open_slots = open_slots + 1;
    end
  end
  
  return open_slots;

end

local function dig_column(height)

  -- Dig from the top down
  turtle.dig()
  for z = 1, height-1 do
    turtle.down()
    z_pos = z_pos - 1
    turtle.dig()
    print("I'm at (" .. x_pos .. "," .. y_pos .. "," .. z_pos .. ")")
  end
  
  -- Wait a second for any falling sand/gravel
  sleep(2)
  
  -- Dig any remaining sand/gravel
  while turtle.detect() do
    turtle.dig()
    sleep(1)
  end
  
  -- Move back up
  for z = 1, height-1 do
    turtle.up()
    z_pos = z_pos + 1
    print("I'm at (" .. x_pos .. "," .. y_pos .. "," .. z_pos .. ")")
  end
  
  -- If there's only one open slot left, let's go drop off my stuff
  local open_slots = check_inventory()
  if open_slots == 1 then
    print("All full up. Dropping off items.");
    
    local return_x, return_y, return_z, direction = x_pos, y_pos, z_pos, direction
    go_to_position(0, 0, 0, 3)
    empty_inventory()
    go_to_position(return_x, return_y, return_z, direction)
    -- empty_inventory()
  end

end

go_to_position(x_pos, y_pos, height-1, direction)
for x = 1, width do
    
  -- Turtle always starts inside the room, so go one less than
  -- you would expect
  for y = 1, length-1 do
    dig_column(height)
    turtle.forward()
    if x % 2 == 1 then
      y_pos = y_pos + 1
    else
      y_pos = y_pos - 1
    end
  end
  
  if(x < width) then -- Stops turtle at top left corner of room
    -- Turn the proper direction, dig the column out, then face the new
    -- row in preparation to start clearing it
    if x % 2 == 1 then
      turtle.turnRight()
      direction = (direction % 4) + 1
      dig_column(height)
      turtle.forward()
      x_pos = x_pos + 1
      turtle.turnRight()
      direction = (direction % 4) + 1
    else
      turtle.turnLeft()
      direction = (direction % 4) - 1
      dig_column(height)
      turtle.forward()
      x_pos = x_pos + 1
      turtle.turnLeft()
      direction = (direction % 4) - 1
    end
  end
  
end
go_to_position(0, 0, 0, 3)
empty_inventory()
go_to_position(0, 0, 0, 1)