[COMPUTERCRAFT] Platform/Cube Building script

--[[
Command usage can be shown by simply executing the script without parameters.
Copyright by Stephan Henrichs, 2012
Licensed under CC BY-NC-SA 3.0
More Information: http://creativecommons.org/licenses/by-nc-sa/3.0/
I'd appreciate to credit me btw :P
]]--
tArgs = {}
tmpArgs = {...}
function printUsage()
  print("Usage: platform <length> <width> <height> [<ofset_length> <offset_width> <offset_heigh>]")
end

-- Testing args
function parseArgs()
  local tmp = tmpArgs
  if tmp[1] == nil or tmp[2] == nil or tmp[3] == nil then
    return false
  else
    tArgs['x'] = tonumber(tmp[1])
    tArgs['z'] = tonumber(tmp[2])
    tArgs['y'] = tonumber(tmp[3])
    if tmp[4] ~= nil and (tmp[5] == nil or tmp[6] == nil) then
      return false
    elseif tmp[4] == nil then
      tArgs['ox'] = 0
      tArgs['oz'] = 0
      tArgs['oy'] = 0
      return true
    else
      tArgs['ox'] = tonumber(tmp[4])
      tArgs['oz'] = tonumber(tmp[5])
      tArgs['oy'] = tonumber(tmp[6])
      return true
    end
  end
end

function selectFirstUsableSlot()
  for i1 = 1,16 do
    if turtle.getItemCount(i1) > 0 then
      turtle.select(i1)
      return true
    end
  end
  return false
end

function go(len)
  for i5=1, len do
    turtle.forward()
  end
end

function buildBlock()
  if selectFirstUsableSlot() then
    turtle.placeDown()
  else
    print("Out of Recources")
    --os.exit()
  end
end

function buildRow(last)
  for i2 = 1, tArgs['x'] do
    buildBlock()
    if (i2 == tArgs['x']) then else
      turtle.forward()
    end
  end
end

local dir = 0

function turn()
  if dir == 1 then
    turtle.turnLeft()
    turtle.forward()
    turtle.turnLeft()
    dir = 0
  else
    turtle.turnRight()
    turtle.forward()
    turtle.turnRight()
    dir = 1
  end
end

function buildLayer()
  for i3 = 1, tArgs['z'] do
    buildRow(i3==tArgs['z'])
    if i3 ~= tArgs['z'] then
      turn()
    end
  end
  dir = 0
end

function buildPlat()
  for i4 = 1, tArgs['y'] do
    buildLayer()
    if i4 ~= tArgs['y'] then
      turtle.up()
    end
    if tArgs['z'] % 2 == 1 then
      turtle.turnRight()
      turtle.turnRight()
      go(tArgs['x']-1)
    end
    turtle.turnRight()
    go(tArgs['z']-1)
    turtle.turnRight()
  end
end

function goToStart()
  local x = tArgs['ox']
  local y = tArgs['oy']
  local z = tArgs['oz']

  if x < 0 then
    x = x * -1
    turtle.turnLeft()
    turtle.turnLeft()
    go(x)
    turtle.turnLeft()
    turtle.turnLeft()
  else
    go(x)
  end
  if z < 0 then
    z = z * -1
    turtle.turnLeft()
    go(z)
    turtle.turnRight()
  else
    turtle.turnRight()
    go(z)
    turtle.turnLeft()
  end
  if y < 0 then
    for i6 = 1, y * -1 do
      turtle.down()
    end
  else
    for i6 = 1, y do
      turtle.up()
    end
  end
end

if parseArgs() then
  goToStart()
  buildPlat()
else
  printUsage()
end