NoteBlock Player

-- NoteBlock Player
-- by MysticT

-- Config

-- id of the controller computer
local nControllerID = 0
-- sides corresponding to each instrument
-- order: piano, bass, bass drum, snare drum, click
local tSides = {}
-- colors corresponding to each note
local tColors = {}
-- pulse sleep time
local nPulse = 0.1

-- Functions

-- clear the screen
local function clear()
    term.clear()
    term.setCursorPos(1, 1)
end

-- detect modem and connect
local function connect()
    for _,s in ipairs(rs.getSides()) do
        if peripheral.isPresent(s) and peripheral.getType(s) == "modem" then
            rednet.open(s)
            return true
        end
    end
    return false
end

-- send a pulse
--[[
table format:
t = {
[side1] = colors,
[side2] = colors,
...
[sideN] = colors,
}
--]]
local function pulse(t)
    for side, c in pairs(t) do
        rs.setBundledOutput(side, c)
    end
    sleep(nPulse)
    for side,_ in pairs(t) do
        rs.setBundledOutput(side, 0)
    end
    sleep(nPulse)
end

-- play the given notes on the given instruments
--[[
table format:
t = {
[i1] = { n1, n2, ..., nN },
[i2] = { n1, n2, ..., nN },
...
[iN] = { n1, n2, ..., nN }
}

i: instrument number (range defined by the sides table)
n: notes (range defined by the colors table)
--]]
local function play(t)
    print("Playing...")
    local tPulse = {}
    for i, notes in pairs(t) do
        print("Instrument: ", i)
        local side = tSides[i]
        if side then
            if type(notes) == "table" then
                print("Notes: ", unpack(notes))
                local c = 0
                for _,n in ipairs(notes) do
                    local k = tColors[n]
                    if k then
                        c = colors.combine(c, k)
                    else
                        print("Unknown note: ", n)
                    end
                end
                tPulse[side] = c
            else
                print("Wrong format. table expected, got ", type(notes))
            end
        else
            print("Unknown Instrument")
        end
    end
    pulse(tPulse)
end

-- Start Program

-- try to connect to rednet
if not connect() then
    print("No modem found")
    return
end

clear()
print("Waiting for messages...")

-- start receiving
while true do
    local id, msg = rednet.receive()
    if id == nControllerID then
        local t = string.match(msg, "<PLAY> (.+)")
        if t then
            local notes = textutils.unserialize(t)
            if notes then
                play(notes)
            end
        end
    end
end