Columna1's NBS Player

term.clear()
term.setCursorPos(1,1)

filename = "Songs/Vanilla Twilight.nbs"
nb = {}
song = {}

insts = {"note.harp","note.bassattack","note.bd","note.snare","note.hat"}
volume = {1,           0.5,              0.4,       0.3,         0.3}

for i = 0,24 do
    nb[i] = 0.5*(2^(i/12))
end

notes = {}
file = fs.open(filename,"rb")
if not file then error("Failed to open file") end
function readByte()
    return file.read()
end
function bytes_to_int(a,b,c,d)--little Endian
    sum = 0
    sum = sum + a
    sum = sum + b * 2 ^ 8
    sum = sum + c * 2 ^ 16
    sum = sum + d * 2 ^ 24
    return sum
end

function readInt()
    e = readByte()
    f = readByte()
    g = readByte()
    h = readByte()
    return bytes_to_int(e,f,g,h)
end

function readShort()
    g = readByte()
    h = readByte()
    e = 0
    f = 0
    return bytes_to_int(g,h,e,f)
end
function readString()
    str = ""
    length = readInt()
    for i = 1,length do
        str = str..string.char(readByte())
    end
    return str
end

function readHeader()
    Length = readShort()
    height = readShort()
    name = readString()
    author = readString()
    originalAuthor = readString()
    description = readString()
    tempo = readShort()
    autoSave = readByte()
    autoSaveDuration = readByte()
    timeSig = readByte()
    minutesSpent = readInt()
    LeftClicks = readInt()
    rightClicks = readInt()
    blocksAdded = readInt()
    blocksRemoved = readInt()
    OrigionalFile = readString()
end

function addNoteBlock(tick, layer, instrument, key)
    if not song[tick] then
        song[tick] = {}
        song[tick][1] = {insts[instrument+1],nb[key-33],volume[instrument+1]}
    else
    --print(#song[tick]+1)
    song[tick][#song[tick]+1] = {insts[instrument+1],nb[key-33],volume[instrument+1]}
    end
end

function readSong()
    tick = -1
    jumps = 0
    while true do
        jumps = readShort()
        if jumps == 0 then
            break
        end
        tick = tick + jumps
        layer = -1
        while true do
            jumps = readShort()
            if jumps == 0 then
                break
            end
            layer = layer + jumps
            inst = readByte()
            key = readByte()
            addNoteBlock(tick, layer, inst, key)
        end
    end
end

function progress(p)
    --51 pixels
    count = 0
    --line 5
    term.setCursorPos(1,19)
    write(math.floor((p/Length)*100).."% Done")
    term.setCursorPos(1,18)
    percent = p/Length
    write("<"..string.rep("=",math.floor(49*percent))..string.rep("-",math.ceil(49-(49*percent)))..">")
end

readHeader()
readSong()
print(name)
print(author)
print(description)
print((tempo/100).." Ticks per second")

block = peripheral.wrap("left")
for i = 1,Length do--loop through ticks
    if song[i] then--if there are notes on there then loop through all of them
        --print(i.." is "..#song[i])
        for j = 1,#song[i] do--loop through the notes
            --print(song[i][j][2])
            block.setCommand("/playsound "..song[i][j][1].." @a ~ ~ ~ "..song[i][j][3].." "..song[i][j][2].." 0")
            block.runCommand()
        end
    end
    --sleep(0.05)
    progress(i)
    sleep(1/(tempo/100))
end
term.setCursorPos(1,15)
file:close()