write

-- write
-- Builds the letters from the input text
-- Written by HarvDad, June 2014

version = "write: Rev 0.1"
instructions = "Place stack(s) of material starting in first slot."

usage = "write <text>"

args = {...}
nArgs = #args


text  = ""

letters = {
	{"A", "====== ", "   =  =", "   =  =", "   =  =", "====== "},
	{"B", "=======", "=  =  =", "=  =  =", "=     =", " == == "},
	{"C", " ===== ", "=     =", "=     =", "=     =", " =   = "},
	{"D", "=======", "=     =", "=     =", "=     =", " ===== "},
	{"E", "=======", "=  =  =", "=  =  =", "=  =  =", "=     ="},
	{"F", "=======", "   =  =", "   =  =", "   =  =", "      ="},
	{"G", " ===== ", "=     =", "=  =  =", "=  =  =", " ===  ="},
	{"H", "=======", "   =   ", "   =   ", "   =   ", "======="},
	{"I", "       ", "=     =", "=======", "=     =", "       "},
	{"J", " ==    ", "=      ", "=      ", "=      ", " ======"},
	{"K", "=======", "   =   ", "  = =  ", " =   = ", "=     ="},
	{"L", "=======", "=      ", "=      ", "=      ", "=      "},
	{"M", "=======", "     = ", "    =  ", "     = ", "======="},
	{"N", "=======", "    =  ", "   =   ", "  =    ", "======="},
	{"O", " ===== ", "=     =", "=     =", "=     =", " ===== "},
	{"P", "=======", "   =  =", "   =  =", "   =  =", "    == "},
	{"Q", " ===== ", "=     =", "= =   =", "==    =", "====== "},
	{"R", "=======", "   =  =", "  ==  =", " = =  =", "=   == "},
	{"S", "=   == ", "=  =  =", "=  =  =", "=  =  =", " ==   ="},
	{"T", "      =", "      =", "=======", "      =", "      ="},
	{"U", " ======", "=      ", "=      ", "=      ", " ======"},
	{"V", "  =====", " =     ", "=      ", " =     ", "  ====="},
	{"W", "=======", " =     ", "  ==   ", " =     ", "======="},
	{"X", "==   ==", "  = =  ", "   =   ", "  = =  ", "==   =="},
	{"Y", "    ===", "   =   ", "===    ", "   =   ", "    ==="},
	{"Z", "==    =", "= =   =", "=  =  =", "=   = =", "=    =="},
	{"?", "     = ", "      =", "= ==  =", "   =  =", "    == "},
	{"!", "       ", "       ", "= =====", "       ", "       "},
	{" ", "       ", "       ", "       ", "       ", "       "},
}

materialSlot = 1

x = 0
y = 0
z = 0
face = 0

-- The following 'face' directions are relative to the starting position of the turtle in this program
north = 0
west = 1
south = 2
east = 3

goForward = 0
goBackward = 1
direction = goForward

currentSlot = 1

function setFace(f)
	if f == 0 then
	  if face == 0 then return end
	  if face == 1 then right() return end
	  if face == 2 then right() right() return end
	  if face == 3 then left() return end
	end

	if f == 1 then
	  if face == 0 then left() return end
	  if face == 1 then return end
	  if face == 2 then right() return end
	  if face == 3 then right() right() return end
	end

	if f == 2 then
	  if face == 0 then left() left() return end
	  if face == 1 then left() return end
	  if face == 2 then return end
	  if face == 3 then right() return end
	end

	if f == 3 then
	  if face == 0 then right() return end
	  if face == 1 then left() left() return end
	  if face == 2 then left() return end
	  if face == 3 then return end
	end
end

function left()
 if face == 0 then face = 1 turtle.turnLeft() return end
 if face == 1 then face = 2 turtle.turnLeft() return end
 if face == 2 then face = 3 turtle.turnLeft() return end
 if face == 3 then face = 0 turtle.turnLeft() return end
 print("function left\(\): Bad face value: ", face)
end

function right()
 if face == 0 then face = 3 turtle.turnRight() return end
 if face == 1 then face = 0 turtle.turnRight() return end
 if face == 2 then face = 1 turtle.turnRight() return end
 if face == 3 then face = 2 turtle.turnRight() return end
 print("function right\(\): Bad face value: ", face)
end

function up()
	while turtle.detectUp() do	-- This loop added in case of falling sand or whatever
	  turtle.digUp()
	end
  turtle.up()
  y = y+1
end

function rise(nBlocks)
  local i
  for i=1,nBlocks do
    up()
  end
end

function down()
  if turtle.detectDown() then
    turtle.digDown()
  end
  turtle.down()
  y = y-1
end

function moveForward(nBlocks)
	for i = 1, nBlocks do
		turtle.forward()
		if face == north then
			z = z + 1
		elseif face == south then
			z = z - 1
		elseif face == east then
			x = x + 1
		elseif face == west then
			x = x - 1
		end
	end

end

function moveBackward(nBlocks)
	for i = 1, nBlocks do
		turtle.back()
		if face == north then
			z = z - 1
		elseif face == south then
			z = z + 1
		elseif face == east then
			x = x - 1
		elseif face == west then
			x = x + 1
		end
	end
end

function home(targetY)
--  print("home:face ", face, ", x = ", x, ", z = ", z)
  if x < 0 then
	setFace(east)
	while x < 0 do
	  moveForward(1)
	end
  else
    if x > 0 then
  	  setFace(west)
	  while x > 0 do
	    moveForward(1)
	  end
    end
  end

  if z < 0 then
	setFace(north)
	while z < 0 do
	  moveForward(1)
	end
  else
    if z > 0 then
  	  setFace(south)
	  while z > 0 do
	    moveForward(1)
	  end
    end
  end

  if y > 0 then
  	while y > 0 do
		down()
	end
  end

  setFace(0)
end

function ensureMaterial()
	if turtle.getItemCount(materialSlot) < 3 then
		organizeMaterial()
	end
	if turtle.getItemCount(materialSlot) < 3 then
		print("No more material")
		return false
	end
	return true
end

function organizeMaterial()
	local i
	materialCount = turtle.getItemCount(materialSlot)

	if materialCount < 3 then
--		print("Attempting to refill slot ", materialSlot)
		for i=2,16 do
			turtle.select(i)
			if turtle.compareTo(materialSlot) then
				turtle.transferTo(materialSlot)
			end
		end
	end
	turtle.select(materialSlot)
end

function getLetter(letter)
	letter = string.upper(letter)

	for i=1,#letters do
		if letters[i][1] == letter then
			return letters[i]
		end
	end
	print("Cannot find entry for \'", letter, "\'")
	return nil
end

function hitTheDeck()
--print("hitTheDeck: y = ", y)
	while y > 0 do
		down()
--		print("  Down")
	end
--	print("    y ends at ", y)
	goingUp = true
end


goingUp = true

function buildLetter(letter)
	letterData = getLetter(letter)
	turtle.select(1)

	if letter == " " then
		right()
		moveForward(7)
		left()
		return
	end
--[[
	if letterData ~= nil then
		for i=1,#letterData do
			print("  ", letterData[i])
		end
	end
--]]

	if letterData == nil then
		print("Cannot build \'", letter, "\'")
		return
	end

	for i=2,#letterData do
		column = letterData[i]
		height = string.len(column)
		if goingUp then
			for j=1,height do
				char = string.sub(column, j, j)
				if char ~= " " then
					ensureMaterial()
					turtle.select(materialSlot)
					turtle.place()
				end
				if j < height then
					up()
				end
			end
		else
			for j=height,1,-1 do
				char = string.sub(column, j, j)
				if char ~= " " then
					ensureMaterial()
					turtle.select(materialSlot)
					turtle.place()
				end
				if j > 1 then
					down()
				end
			end
		end

		if goingUp then
			goingUp = false
		else
			goingUp = true
		end

		right()
		moveForward(1)
		left()
	end
end



if nArgs == 0 then
	print(version)
	print(instructions)
	print(usage)
	return
end

text = ""
for i=1,nArgs do
	text = text .. " " .. args[i]
end
text = string.sub(text, 2)

for i=1,string.len(text) do
	buildLetter(string.sub(text,i,i))
	right()
	moveForward(1)
--	hitTheDeck()
	moveForward(1)
	left()
end

home(0)