local api = {}
local storage
local save
local PROTOCOL = "TURTI_DIMENSION_PROTOCOL"
local RESPONSE_EVENT = PROTOCOL .. "_RESPONSE_EVENT"
local RESPONSE_TIMEOUT = 3

local function openRednet()
    local side
    peripheral.find("modem", function(name, modem)
        if modem.isWireless() then
            side = name
        end
    end)
    if not rednet.isOpen(side) then
        rednet.open(side)
    end
end

local function listenerThread()
    openRednet()
    while true do
        local _, _, _, replyChannel, message, distance = os.pullEvent("modem_message")
        if type(message) == "table" and message["sProtocol"] == PROTOCOL and message["message"] then
            local msg = getTableFromSaveText(message["message"])
            if msg.type == "dimensionRequest" then
                if storage.dimension and distance then
                    rednet.send(replyChannel, getTableSaveText({
                        type = "dimensionResponse",
                        dimension = storage.dimension,
                        callId = msg.callId
                    }), PROTOCOL)
                end
            elseif msg.type == "dimensionResponse" then
                storage.responses[msg.callId] = msg.dimension
                save()
                os.queueEvent(RESPONSE_EVENT)
            end
        end
    end
end

function api.hostDimension(dimension)
    storage.dimension = dimension
    save()
end

local function tryGetDimension()
    local callId = storage.currentCallId
    storage.currentCallId = storage.currentCallId + 1
    save()
    rednet.broadcast(getTableSaveText({
        type = "dimensionRequest",
        callId = callId
    }), PROTOCOL)
    local timer = os.startTimer(RESPONSE_TIMEOUT)
    while true do
        local event, arg = os.pullEvent()
        if event == RESPONSE_EVENT then
            local dimension = storage.responses[callId]
            storage.responses[callId] = nil
            save()
            return dimension
        elseif event == "timer" then
            if arg == timer then
                return nil
            end
        end
    end
end

function api.getDimension()
    while true do
        local dimension = tryGetDimension()
        if dimension then
            return dimension
        end
    end
end

return {
    name = "dimension",
    onSetup = function()
        ThreadManager.startThread(
                listenerThread, "dimension listener"
        )
    end,
    onInitStorage = function(_storage, _save)
        storage = _storage
        save = _save
        if not storage.responses then
            storage.responses = {}
            storage.currentCallId = 0
        end
    end,
    api = api
}