Printer tool

debugMode = false
function split(str,splitter)
    if not splitter then return end
    if not str then return end
    words = {}
    i=0
    for part in string.gmatch(str, "[^%"..splitter.."]+") do -- get each part
        i=i+1
        words[i] = part
    end
    return words
end
string.split = split

if isTurtle() then
    printer = peripheral.wrap("top")
    if printer == nil then
        print("You are currently using a turtle. Turtles must be placed under the printer for this program to work properly.")
    end
    if turtle.craft == nil then
        print("You are currently using a non-crafty turtle. Either use a regular computer or use a crafty turtle.")
    end
else
    printer = peripheral.find("printer")
end

function dropFinishedBook()

end

function hasInk()
    if printer.getInkLevel() > 0 then
        return true
    else
        return false
    end
end

function hasPaper()
    if printer.getPaperLevel() > 0 then
        return true
    else
        return false
    end
end

function checkPrintingRequirements()
    if hasPaper() == false or hasInk() == false then
        print("Printing is impossible: Either ink or paper is missing")
        while hasPaper() == false or hasInk() == false do
            sleep(1)
        end
    end
end

function isTurtle()
    if type(turtle) == "table" then
        return true
    else
        return false
    end
end

function isStringUseOptimal()
        -- if the inventory is sorted like so:
        -- P P P
        -- P P P
        -- P B S
        -- P=Page, B=Book, S=String
        -- Then the function returns true.
        -- This setup uses 1 string for 7 pages instead of one for one
    for i=1,16 do
        if turtle.getItemCount(i) == 0 then
            if i <= 9 and i%4 ~= 0 then
                turtle.select(i)
                return false
            end
        end
    end
    return true
end

function craftBook()
    if isStringUseOptimal() then
        turtle.select(10)
        turtle.craft()
        turtle.select(1)
        turtle.suckUp()
        return true
    else
        turtle.suckUp()
        return false
    end
end

function getPage(fileName)
    local h = fs.open(fileName, "r")
    file = h.readAll()
    h.close()
    return file
end

function fitWords(line)
    local words = string.split(line, " ")
    local line = {}
    local sum = 0
    local j=1
    line[j] = ""
    for i,word in pairs(words) do
        sum = sum + string.len(word) + 1
        if sum < 25 then
            line[j] = line[j] .. word .. " "
        else
            sum = string.len(word) + 1
            j=j+1
            line[j] = word .. " "
        end
        -- print("line["..j.."] = "..line[j] .. " (" .. sum .. ")")
    end
    return line
end

function printBook(text)
    if debugMode then
        -- Debug mode. It doesn't print shit
        printer = fs.open("test", "w")
        printer.setCursorPos = function() end
        printer.newPage = function() return true end
        printer.endPage = function() return true end
        printer.getPaperLevel = function() return 1 end
        printer.getInkLevel = function() return 1 end
        printer.write = printer.writeLine
    end

    lines = fitWords(text)

    if #lines%21 == 0 then
        numberOfPages = #lines/21
    else
        numberOfPages = math.floor(#lines/21) + 1
    end
    -- print(numberOfPages)

    for page=0, numberOfPages-1 do
        checkPrintingRequirements()
        printer.newPage()
        for line=1, 21 do
            if line+21*page <= #lines then
                printer.setCursorPos(1, line)
                printer.write(lines[line+21*page])
                print(lines[line+21*page])
                --print(line+21*page)
            end
        end
        if printer.endPage() == false then
            print("Error: Printer is full. Please clear the printer tray.")
            while printer.endPage() == false do
                sleep(1)
            end
        end

        if isTurtle() then
            craftBook()
        end
    end
    if debugMode then
        printer.close()
    end

    if isTurtle() then
        turtle.select(10)
        turtle.craft()
        dropFinishedBook()
    end
end

function printFile(fileName)
    h = fs.open(fileName, "r")
    local text = h.readAll()
    h.close()
    printBook(text)
end