[CC] Auto-Jukebox

-- List of all known tracks, and their lengths.
local tTracks = {
    {TrackName = "C418 - 13", Length = 2 * 60 + 58},
    {TrackName = "C418 - cat", Length = 3 * 60 + 05},
    {TrackName = "C418 - blocks", Length = 5 * 60 + 45},
    {TrackName = "C418 - chirp", Length = 3 * 60 + 05},
    {TrackName = "C418 - far", Length = 2 * 60 + 54},
    {TrackName = "C418 - mall", Length = 3 * 60 + 17},
    {TrackName = "C418 - mellohi", Length = 1 * 60 + 36},
    {TrackName = "C418 - stal", Length = 2 * 60 + 30},
    {TrackName = "C418 - strad", Length = 3 * 60 + 08},
    {TrackName = "C418 - ward", Length = 4 * 60 + 11},
    {TrackName = "C418 - 11", Length = 1 * 60 + 11},
    {TrackName = "C418 - wait", Length = 3 * 60 + 58}
}

local tJukeBoxes = {}
-- tJukeBoxes format: Array of objects.
--   DeviceName: (String) Name of peripheral
--   TrackName: (String) Name of the loaded disc
--   TrackLength: (Number) Length of the loaded disc

-- Finds all Auto-Jukeboxes attached to the network, and saves them, with their loaded disc, to the tJukeBoxes table.
local function BuildJukeBoxList()
    local tPeripherals
    local nIndex
    local tStack
    local nTrackIndex

    tJukeBoxes = {}

    tPeripherals = peripheral.getNames()
    for nIndex = 1, #tPeripherals do
        if peripheral.getType(tPeripherals[nIndex]) == "auto_jukebox" then
            tStack = peripheral.call(tPeripherals[nIndex], "getStackInSlot", 1)

            if tStack.disk ~= nil then
                -- Find the length of the track.
                for nTrackIndex = 1, #tTracks do
                    if tTracks[nTrackIndex].TrackName == tStack.disk.label then
                        tJukeBoxes[#tJukeBoxes + 1] = {DeviceName = tPeripherals[nIndex], TrackName = tStack.disk.label, TrackLength = tTracks[nTrackIndex].Length}
                        break
                    end
                end
            end
        end
    end
end

-- Plays the disc loaded in the given jukebox.
local function PlayTrack(tJukeBox)
    peripheral.call(tJukeBox.DeviceName, "play")
end

-- Stops all playing tracks.
local function StopAll()
    local nIndex

    for nIndex = 1, #tJukeBoxes do
        peripheral.call(tJukeBoxes[nIndex].DeviceName, "stop")
    end
end

-- Takes a number of seconds and returns a formatted string in m:ss format.
local function FormatTime(nSeconds)
    local nMinutesOut
    local nSecondsOut
    local sSeconds

    nMinutesOut = math.floor(nSeconds / 60)
    nSecondsOut = nSeconds - (nMinutesOut * 60)

    sSeconds = tostring(nSecondsOut)
    if #sSeconds < 2 then
        sSeconds = "0" .. sSeconds
    end

    return tostring(nMinutesOut) .. ":" .. sSeconds
end

local nTrack

BuildJukeBoxList()

print("Track list:")
for nTrack = 1, #tJukeBoxes do
    print("  " .. tJukeBoxes[nTrack].TrackName .. " (" .. FormatTime(tJukeBoxes[nTrack].TrackLength) .. ")")
end

print()

while true do
    for nTrack = 1, #tJukeBoxes do
        StopAll()
        PlayTrack(tJukeBoxes[nTrack])
        print("Playing \"" .. tJukeBoxes[nTrack].TrackName .. "\" (" .. FormatTime(tJukeBoxes[nTrack].TrackLength) .. ")")
        os.sleep(tJukeBoxes[nTrack].TrackLength)
    end
end