[CC] Multi Color Printer v0.4

--[[     Multi Color Printer v0.4      ]]--
--[[ Made By Orwell (aka this_is_1984) ]]--

local function moveUp()
  if not (turtle.up() and turtle.forward()) then
      error('The area above and below the turtle should be cleared!')
  end
end

local function moveUpBack()
  if not (turtle.back() and turtle.up()) then
      error('The area above and below the turtle should be cleared!')
  end
end

local function moveDown()
  if not (turtle.down() and turtle.forward()) then
      error('The area above and below the turtle should be cleared!')
  end
end

local function moveDownBack()
  if not (turtle.back() and turtle.down()) then
      error('The area above and below the turtle should be cleared!')
  end
end

local function feedPaper()
  turtle.select(16)
  local paperLevel = peripheral.call('front','getPaperLevel')
  if paperLevel ~= 1 then
    moveUp()
    if paperLevel > 1 then
      turtle.suckDown()
    else
      turtle.suckUp(1)
    end
    turtle.dropUp(turtle.getItemCount(16)-1)
    turtle.dropDown(1)
    moveDownBack()
  end
end

local function cyclePaper()
  moveDown()
  turtle.select(16)
  turtle.suckUp()
  moveUpBack()
  moveUp()
  turtle.dropDown(1)
  moveDownBack()
end

local function outputPaper()
  turtle.select(16)
  moveDown()
  turtle.suckUp()
  turtle.dropDown()
  moveUpBack()
end

local w,h = 25,21

Pixel = {}
Pixel.__index = Pixel

function Pixel.create(char, color)
  local pixel = {}
  setmetatable(pixel, Pixel)
  pixel.char = char
  pixel.color = color
  return pixel
end

local color = {
colors.green,
colors.brown,
colors.black,
colors.pink,
colors.yellow,
colors.orange,
colors.magenta,
colors.purple,
colors.cyan,
colors.red,
colors.lightBlue,
colors.lightGray,
colors.gray,
colors.lime,
colors.blue,
}

local function round(n)
  if n-math.floor(n) <= 0.5 then
    return math.floor(n)
  else
    return math.ceil(n)
  end
end

Page = {}
Page.__index = Page

function newPage()
  local page = {}
  setmetatable(page, Page)
  page.image = {}
  page.width = w
  page.height = h
  page.x = 1
  page.y = 1
  for y=1,page.height do
    page.image[y]={}
  end
  page.colors = {}
  page.write =
    function(str, clr)
      clr = clr or colors.black
      for i=1,math.min(#str,page.width-page.x) do
        page.image[page.y][page.x+i] = Pixel.create(string.sub(str,i,i),clr)
      end
      page.x = math.min(page.width, page.x + #str)
      page.colors[clr] = true
    end
  page.getCursorPos = function() return page.x,page.y end
  page.setCursorPos = function(x,y) if x > 0 and x<= page.width and y > 0 and y<=page.height then page.x,page.y=round(x),round(y) end end
  page.print = function(title) printPage(page,title) end
  page.clear = function() for i=1,#page.image do page.image[i] = {} end end
  return page
end

function printPage(page, title)
  local printerSide = 'front'
  local printer = peripheral.wrap(printerSide)
  if not printer or peripheral.getType(printerSide) ~= "printer" then
    error("No printer found in front of turtle!")
  end

  feedPaper()
  if printer.getPaperLevel() ~= 1 then
    error("There should be exactly one page in the printer at the time of printing!")
  end

  for i,v in ipairs(color) do
    if page.colors[v] == true then
      turtle.select(i)
      if (turtle.getItemCount(i) == 0) then
        print('Out of dye in slot '..i..'.')
    os.pullEvent('key')
      end
      turtle.drop(1)
      printer.newPage()
      for x=1,w do
        for y=1,h do
          local pixel = page.image[y][x]
          if pixel and pixel.color == v then
            printer.setCursorPos(x,y)
            printer.write(pixel.char)
          end
        end
      end
      if (i == #color) then
        if title then
          printer.setPageTitle(title)
        end
        printer.endPage()
      else
        printer.endPage()
        cyclePaper()
      end
    end
  end
  outputPaper()
end