StationPA

local LONG_PING = 5
local MEDIUM_PING = 1
local SHORT_PING = 0.

local RANDOM_MIN = 60
local RANDOM_MAX = 120

local AUDIO_PATH = "audio/transit/"

local VOLUME = 2.0
local inst1 = "pling"
local inst2 = "iron_xylophone"
local inst3 = "bass"

local JINGLES = {
    arrival = {
        {duration=0.5, notes={{inst1, VOLUME, 20}, {inst2, VOLUME, 20}, {inst3, VOLUME, 4}}},
        {duration=0.5, notes={{inst1, VOLUME, 16}, {inst2, VOLUME, 16}, {inst3, VOLUME, 8}}},
        {duration=0.5, notes={{inst1, VOLUME, 18}, {inst2, VOLUME, 18}, {inst3, VOLUME, 6}}},
        {duration=0.5, notes={{inst1, VOLUME, 11}, {inst2, VOLUME, 11}, {inst3, VOLUME, 11}}}
    },
    random = {
        {duration=0.4, notes={{inst1, VOLUME, 4}, {inst2, VOLUME, 4}, {inst3, VOLUME, 16}}},
        {duration=0.4, notes={{inst1, VOLUME, 8}, {inst2, VOLUME, 8}, {inst3, VOLUME, 11}}},
        {duration=0.4, notes={{inst1, VOLUME, 11}, {inst2, VOLUME, 11}, {inst3, VOLUME, 8}}}
    }
}

function splitWord(target, word)
    local i, j = string.find(target, word)
    if i == nil then return target end
    return string.sub(target, 1, i - 1), string.sub(target, j + 1, -1)
end
function getName(name)
    return string.gfind(string.gsub(name, "%s%d", ""), "[%a%s%p]+")()
end
function getFilename(name)
    return string.gsub(getName(name), "%s", "_")
end
function getNumber(name)
    return tonumber(string.gfind(name, "%d+$")())
end

local decoder = require("cc.audio.dfpwm").make_decoder()
local speaker = peripheral.find("speaker")
local stations = {}
for _, name in pairs(peripheral.getNames()) do
    pType = peripheral.getType(name)
    if pType == "Create_Station" then
        local station = peripheral.wrap(name)
        station.fullName = station.getStationName()
        station.name=getName(station.fullName)
        station.platform=getNumber(station.fullName)
        station.present=station.isTrainPresent()
        table.insert(stations, station)
    end
end

shell.run("clear")

local pingTimer = os.startTimer(SHORT_PING)
local randomTimer = os.startTimer(math.random(RANDOM_MIN, RANDOM_MAX))
local soundTasks = {}
function addSoundTasks(newTasks)
    for i=1, #newTasks do
        if newTasks[i].filename ~= nil then
            for chunk in io.lines(AUDIO_PATH..newTasks[i].filename, 16*1024) do
                soundTasks[#soundTasks+1] = {buffer=chunk}
            end
        else
            soundTasks[#soundTasks+1] = newTasks[i]
        end
    end
end
local soundTaskIndex = 1
local soundTaskTimer = nil
local soundPlaying = false
while true do
    local event, id = os.pullEvent()
    local startSound = false
    if event == "timer" and id == pingTimer then
        local newTime = LONG_PING
        for i, station in pairs(stations) do
            if station.isTrainPresent() then
                if not station.present then
                    stations[i].present = true
                    newTime = math.min(newTime, MEDIUM_PING)
                    local name = station.getTrainName()
                    write(name)

                    if not soundPlaying then
                        addSoundTasks(JINGLES.arrival)
                    end

                    local lineFilename = "lines/"..getFilename(name)..".dfpwm"
                    if fs.exists(AUDIO_PATH..lineFilename) then
                        addSoundTasks({{filename=lineFilename}})
                    else
                        addSoundTasks({{filename="Train.dfpwm"}})
                    end
                    if station.hasSchedule() then
                        local schedule = station.getSchedule()
                        local entries = schedule.entries
                        local progress = schedule.progress -- BUG: This value is often incorrect.
                        if progress == nil then progress = 1 end
                        for i=1, #entries do
                            if entries[i].instruction.id == "create:destination" and entries[i].instruction.data.text == station.fullName then
                                progress = i
                                break
                            end
                        end
                        local stations = {}
                        local label = nil
                        local index = math.mod(progress, #entries) + 1
                        while index ~= progress do
                            --write(index..": ")
                            local entry = entries[index]
                            if entry.instruction.id == "create:destination" then
                                stations[#stations + 1] = entry.instruction.data.text
                                --print(stations[#stations])
                            elseif entry.instruction.id == "create:rename" then
                                label = entry.instruction.data.text
                                --print("-> "..label)
                            end
                            index = math.mod(index, #entries) + 1
                        end

                        if label ~= nil then
                            write(" to "..label)
                            local name, andName = splitWord(label, " and ")
                            local isVia = false
                            if andName == nil then
                                isVia = true
                                name, andName = splitWord(label, " via ")
                            end
                            addSoundTasks({
                                {filename="To.dfpwm"},
                                {duration=0.4},
                                {filename="stations/"..getFilename(name)..".dfpwm"}
                            })
                            if andName ~= nil then
                                addSoundTasks({{duration=0.2}})
                                if isVia then addSoundTasks({{filename="Via.dfpwm"}})
                                else addSoundTasks({{filename="And.dfpwm"}}) end
                                addSoundTasks({{duration=0.2}, {filename="stations/"..getFilename(andName)..".dfpwm"}})
                            end
                        end
                    end
                    addSoundTasks({{filename="ArrivesNowOnTrack.dfpwm"}})
                    addSoundTasks({
                        {duration=0.2},
                        {filename="numbers/"..station.platform..".dfpwm"},
                        {duration=1.0}
                    })
                    startSound = true
                    randomTimer = os.startTimer(math.random(RANDOM_MIN, RANDOM_MAX))

                    print(" arrived on platform "..station.platform)
                end
            else
                stations[i].present = false
                if station.isTrainEnroute() then
                    newTime = math.min(newTime, MEDIUM_PING)
                elseif station.isTrainImminent() then
                    newTime = math.min(newTime, SHORT_PING)
                    randomTimer = nil
                end
            end
        end
        pingTimer = os.startTimer(newTime)
    end
    if event == "timer" and id == randomTimer then
        local filenames = fs.list(AUDIO_PATH.."random")
        local randomFile = filenames[math.random(#filenames)]
        print("Playing announcment \""..randomFile.."\"...")
        addSoundTasks(JINGLES.random)
        addSoundTasks({{filename="random/"..randomFile}})
        startSound = true
        randomTimer = os.startTimer(math.random(RANDOM_MIN, RANDOM_MAX))
    end
    if (event == "timer" and id == soundTaskTimer) or (event == "speaker_audio_empty") or (startSound and not soundPlaying) then
        soundPlaying = true
        local soundTask = soundTasks[soundTaskIndex]
        if soundTask == nil then
            soundPlaying = false
            soundTasks = {}
            soundTaskIndex = 1
        else
            if soundTask.notes ~= nil then
                for _, note in pairs(soundTask.notes) do
                    speaker.playNote(unpack(note))
                end
            elseif soundTask.buffer ~= nil then
                speaker.playAudio(decoder(soundTask.buffer), VOLUME)
            end
            if soundTask.duration ~= nil then
                soundTaskTimer = os.startTimer(soundTask.duration)
            end
            soundTaskIndex = soundTaskIndex + 1
        end
    end
end