rrp-server

local tArgs = { ... }
local w,h = term.getSize()
local dispMode = true
if w < 21 or h < 3 then
    error("Screen too small")
elseif w < 30 or h < 10 then
    dispMode = false
    print("This is small...")
    sleep(1)
end
local old = term.current()
local ch = nil
local rsSide = "back"
local connectionHeader = nil
local syncKey = nil
local syncChannel = 65000
local function log(msg)
    print("[" .. textutils.formatTime(os.time()) .. "] " .. msg)
end
local function reload()
    local handle = fs.open("/.rrp","r")
    ch = tonumber(handle.readLine())
    connectionHeader = handle.readLine()
    syncKey = handle.readLine()
    handle.close()

    local m = {peripheral.find("modem")}
    for k,v in pairs(m) do
        v.open(ch)
        v.open(syncChannel)
    end
end

local function generate()
    print("Generating keys...")
    local channel = math.random(1024,43600)
    local header = "["
    for i=1,20 do
        header = header .. string.char(math.random(65,89))
    end
    header = header .. "]"
    local key = "R"
    for i=1,4 do
        key = key .. string.char(math.random(97,117))
    end
    for i=1,6 do
        key = key .. math.random(0,9)
    end
    print("Channel: " .. channel)
    print("Header: " .. header)
    print("Sync key: " .. key)
    print("Saving...")
    local handle = fs.open("/.rrp","w")
    handle.writeLine(tostring(channel))
    handle.writeLine(tostring(header))
    handle.writeLine(tostring(key))
    handle.close()
end

local function mainServer()
    while true do
        local r = {os.pullEvent("modem_message")}
        if r[3] == ch then
            if string.find(r[5],connectionHeader) then
                if string.sub(r[5],#connectionHeader + 1) == "on" then
                    rs.setOutput(rsSide,true)
                    log("[LOG] Received ENABLE signal")
                end
                if string.sub(r[5],#connectionHeader + 1) == "off" then
                    rs.setOutput(rsSide,false)
                    log("[LOG] Received DISABLE signal")
                end
            end
        end
    end
end
local function inform()
    while true do
        if dispMode == true then
        local x,y = old.getSize()
        old.setCursorPos(1,y)
        old.write("Sync key: " .. syncKey)
        old.setCursorPos(1,1)
        old.write("Remote redstone by Rahph ")
        local timestring = textutils.formatTime(os.time())
        old.setCursorPos(x-#timestring-1,1)
        old.write(timestring)
        old.setCursorPos(1,2)
        old.write(string.rep("=",x))
        old.setCursorPos(1,y-1)
        old.write(string.rep("=",x))
        sleep(1)
        else
        local x,y = old.getSize()
        old.setCursorPos(1,y)
        old.write("Sync key: " .. syncKey)
        old.setCursorPos(1,1)
        old.write("RRP small mode")
        sleep(1)
        end
    end
end
local function syncServer()
    while true do
        local r = {os.pullEvent("modem_message")}
        if r[3] == syncChannel then
            if r[5] == syncKey then
                local info = {}
                info["header"] = connectionHeader
                info["channel"] = tonumber(ch)
                info["identify"] = syncKey
                local m = {peripheral.find("modem")}
                for k,v in pairs(m) do
                    v.transmit(syncChannel,syncChannel,textutils.serialise(info))
                end
                log("[LOG] Synchronised with a device " .. r[6] .. " blocks away")
            end
        end
    end
end
if not tArgs[1] then
reload()
local x,y = term.getSize()
if dispMode == true then term.redirect(window.create(term.current(),1,3,x,y-2))
else term.redirect(window.create(term.current(),1,2,x,y-1))
end
parallel.waitForAny(inform,syncServer,mainServer)
elseif tArgs[1] == "regen" then
generate()
else
error("No.")
end