nMon

--SETUP
local barColor = colors.cyan
local barTitleDefault = "Record Player"
local notesInfoText = "&1Harp&9  &4Snare&9  &5Hat&9  &2Bass&9  &3BaseDrum&9"
--END SETUP

os.loadAPI("gcapi")

--INTERNAL VARIABLES

local barTitle = barTitleDefault
local mon = peripheral.find("monitor")
local max_x, max_y = mon.getSize()

local song = {} --

--PROGRAMS

function updateTitleBar()
    if song["name"] then
        barTitle = barTitleDefault .. " - Playing: " .. song["name"]
    end

    mon.setBackgroundColor(barColor)
    for x=1, max_x, 1 do
        mon.setCursorPos(x,1)
        mon.write(" ")
    end
    mon.setCursorPos(gcapi.getCenter(max_x, barTitle), 1)
    mon.write(barTitle)
end

function setupMonitor()
    barTitle = barTitleDefault

    mon.setBackgroundColor(colors.white)
    mon.clear()

    mon.setTextColor(colors.black)

    updateTitleBar()

    for x=1, max_x, 1 do
        mon.setCursorPos(x,max_y)
        mon.write(" ")
    end
    mon.setCursorPos(gcapi.getCenter(max_x, string.len(notesInfoText)-((#string.split(notesInfoText, "&")-1)*2)), max_y)
    gcapi.customMonitorWrite(mon, notesInfoText)
end

function setSong(s)
    song = s
end

function printNotes(tick)
    local tarjetX = gcapi.getCenter(max_x)

    mon.setBackgroundColor(colors.black)
    for y=2, max_y-1,1 do
        mon.setCursorPos(tarjetX,y)
        mon.write(" ")
    end
    for i=1,#song,1 do
        tickTable = song[i]
        local x = -tick+gcapi.getCenter(max_x)+i
        if x > max_x then
            break
        end
        if (x > 0) and tickTable then
            for instrumentID, notePitchs in pairs(tickTable) do
                for _,pitchID in pairs(notePitchs) do
                    mon.setBackgroundColor(2^instrumentID)
                    mon.setCursorPos(x,gcapi.getCenter(max_y, 24)+pitchID)
                    mon.write(" ")
                end
            end
        end
    end
end

function updateMonitor(tick)
    setupMonitor()
    printNotes(tick)
end