computersign

local TextFile
MonitorSide = "bottom"
Monitor = peripheral.wrap(MonitorSide)
MonitorLinePosition = 1
MonitorCaretPosition = 1
MonitorLength = 0
CurrentColour = colours.white

function OpenFile()
    return fs.open("text", "r")
end

function PrintLine(str, textColour)
    Monitor.setCursorPos(1, MonitorLinePosition)
    Monitor.setTextColour(textColour)
    Monitor.write(str)
    MonitorLinePosition = MonitorLinePosition + 1
end

function Print(str, textColour)
    Monitor.setCursorPos(MonitorCaretPosition, MonitorLinePosition)
    Monitor.setTextColour(textColour)
    Monitor.write(str)
    MonitorCaretPosition = MonitorCaretPosition + 1
    if (MonitorCaretPosition >= MonitorLength) then
        MonitorCaretPosition = 1
        MonitorLinePosition = MonitorLinePosition + 1
    end
end

function ParseColour(code)
    if (code == "0") then return colours.black end
    if (code == "1") then return colours.blue end
    if (code == "2") then return colours.green end
    if (code == "3") then return colours.cyan end
    if (code == "4") then return colours.red end
    if (code == "5") then return colours.purple end
    if (code == "6") then return colours.orange end
    if (code == "7") then return colours.lightGrey end
    if (code == "8") then return colours.grey end
    if (code == "9") then return colours.lightBlue end
    if (code == "a") then return colours.lime end
    if (code == "b") then return colours.lightBlue end
    if (code == "c") then return colours.red end
    if (code == "d") then return colours.pink end
    if (code == "e") then return colours.yellow end
    if (code == "f") then return colours.white
    else return colours.white end
end

function ParseAndPrintTextLine(line)
    if (line == "" or line == nil) then
        return
    end
    for i = 1, string.len(line), 1 do
        local character = string.sub(line, i, i + 1)
        if (character == "&") then
            i = i + 1
            local colourCode = string.sub(line, i, i + 1)
            CurrentColour = ParseColour(colourCode)
        else
            Print(character, CurrentColour)
        end
    end
    MonitorLinePosition = MonitorLinePosition + 1
    MonitorCaretPosition = 1
end

function Main()
    TextFile = OpenFile()
    local monX, monY = Monitor.getSize()
    MonitorLength = monX
    print("Carrot's monitor thingy.")
    print("Writing text...")
    Monitor.setBackgroundColor(colours.black)
    Monitor.setTextColor(colours.black)
    Monitor.clear()
    Monitor.setTextColor(colours.white)
    local index = 0
    while (true) do
        local line = TextFile.readLine()
        ParseAndPrintTextLine(line)
        if (line == nil) then
            break
        end
        index = index + 1
    end
    print("Wrote all text to the the monitor")
end

Main()