turtle jukebox v1

-- Turtle jukebox v1 by DrPepper
-- Needs a turtle and a drive from Computercraft, the former placed above the latter
-- Plays all musical disks loaded into the turtle inventory in random order

local ScanInventory, FindDrive, TryEmptyDrive, LoadDisk, PlayRandom
local records, drive, currentSong, disksTotal
local recordLengths = {}
recordLengths["13"]         = 178
recordLengths["cat"]        = 185
recordLengths["blocks"]     = 345
recordLengths["chirp"]      = 185
recordLengths["far"]        = 174
recordLengths["mall"]       = 197
recordLengths["mellohi"]    = 96
recordLengths["stal"]       = 150
recordLengths["strad"]      = 188
recordLengths["ward"]       = 251
recordLengths["11"]         = 71
recordLengths["wait"]       = 238
recordLengths["otherside"]  = 195
recordLengths["5"]          = 178
recordLengths["pigstep"]    = 148
local pause = 5

function ScanInventory()
    records = {}
    disksTotal = 0
    for i = 1, 16 do
        local res = turtle.getItemDetail(i, true)
        if res ~= nil then
            if res.name ~= nil and string.match(tostring(res.name), "minecraft.record") then
                records[i] = string.sub(tostring(res.name), 18)
                disksTotal = disksTotal + 1
            else
            turtle.select(i)
            turtle.dropUp()
            end
        end
    end
    if disksTotal == 0 then
        print("Add some music disks")
    end
end

function FindDrive()
    if peripheral.getType("bottom") == "drive" then
        drive = peripheral.wrap("bottom")
    else
        print("No drive below turtle")
        return false
    end
end

function TryEmptyDrive()
    if records == nil then
        print("Run ScanInventory() first")
        return false
    end
    if drive == nil then
        print("Run FindDrive() first")
        return false
    end
    if not drive.isDiskPresent() then
        return true
    end
    local slot
    for i = 1, 16 do
        if records[i] == nil then
            slot = i
            break
        end
    end
    if slot == nil then
        print("No empty slots")
        return false
    end
    turtle.select(slot)
    turtle.suckDown()
end

function TryLoadDisk(slot)
    if records == nil then
        print("Run ScanInventory() first")
        return false
    end
    currentSong = records[slot]
    if drive == nil then
        print("Run FindDrive() first")
        return false
    end
    if drive.isDiskPresent() then
        print("Run TryEmptyDrive() first")
        return false
    end
    turtle.select(slot)
    turtle.dropDown()
    drive.playAudio()
    if recordLengths[currentSong] ~= nil then
        print(string.format("Playing \"%s\", %d seconds", records[slot], recordLengths[currentSong] ))
        sleep(recordLengths[currentSong] + pause)
    end
end

function PlayRandom()
    if records == nil or disksTotal == nil then
        print("Run ScanInventory() first")
        return false
    end
    local rand = math.random(1, disksTotal)
    print ("Rand: " .. rand .. " of " .. disksTotal)
    local slot
    for i = 1, 16 do
        if records[i] ~= nil then
            turtle.select(i)
            sleep(0.5)
            rand = rand - 1
            if rand == 0 then
                slot = i
                break
            end
        end
    end
    if slot == nil then
        print("WTF")
        return false
    end
    TryLoadDisk(slot)
    ScanInventory()
    TryEmptyDrive()
    ScanInventory()
end

if not turtle then
    print("You need a turtle to run this")
    return
end

ScanInventory()
FindDrive()
TryEmptyDrive()
ScanInventory()
while true do
    PlayRandom()
end