Tesla Controller

rednet.open "top"
local radar = peripheral.find "radar"
local side = "right"
local onoff = false
local admin = "gollark"
local alreadyHandledTrespass = false

local banned = {
    "demhydraz",
    "Terrariola"
}

function speak(msg)
    rednet.broadcast({"GTech Base Defense System: ID " .. os.getComputerID(), msg}, "chat_announce")
end

function checkTrespassers(radarOutput)
    for _, data in pairs(radarOutput) do
        for _, bannedName in pairs(banned) do
            if data.name == bannedName then
                return true, bannedName
            end
        end
    end

    return false
end

function set()
    redstone.setOutput(side, onoff)
end

function scanNearby()
    while true do
        local players = radar.getPlayers()
        local trespassersExist, name = checkTrespassers(players)

        if trespassersExist then
            print "Trespass detected"
            if not alreadyHandledTrespass then
                speak "TRESPASSER DETECTED. Coil engaged."
                if name then
                    speak("Go away, " .. name .. ".")
                    if name == "nagoL2015" then
                        speak "Dark Lords are not welcome here, dank or not."
                    end
                end
                alreadyHandledTrespass = true
            end
            onoff = true
        else
            if alreadyHandledTrespass then
                onoff = false
            end
            alreadyHandledTrespass = false
        end

        set()

        sleep(1)
    end
end

function controlCoil()
    while true do
        local _, raw = rednet.receive "chat_message"
        local msg, usr = raw[2], raw[1]

        local cmd = string.sub(msg or "", 2) -- msg is somehow nil sometimes

        print(usr, msg, cmd)

        if usr == admin then
            if cmd == "toggle" then
                onoff = not onoff
                speak("Message acknowledged. Coil set to: " .. tostring(onoff) .. ".")
                set()
            elseif cmd == "reboot" then
                speak "Rebooting..."
                os.reboot()
            end
        end
    end
end

speak "System ready."

parallel.waitForAll(controlCoil, scanNearby)