Explorer 4

-- Network Explorer

print("Network Explorer");

function getMonitor()
    return peripheral.find('monitor');
end
function getModem()
    return peripheral.find('modem');
end
function split(s, delimiter)
    result = {};
    for match in (s..delimiter):gmatch("(.-)"..delimiter) do
        table.insert(result, match);
    end
    return result;
end

print("Searching for modem and monitor");
modem = getModem();
if modem == nil then
    print("No modem found");
    exit();
end
print("Modem found");

monitor = getMonitor();
if monitor == nil then
    print("No monitor found");
end
messages = {};
messageIndex = -1;

function display()
    local displayWidth, displayHeight = monitor.getSize();
    local firstIndex = messageIndex - displayHeight;
    if firstIndex < 0 then
        firstIndex = 0;
    end
    monitor.clear();
    monitor.setCursorPos(0, 0);
    monitor.write("Network Explorer by Westar");
    for i=firstIndex, messageIndex, 1 do
        monitor.write(messages[i].senderId..","..messages[i].protocol..","..messages[i].message);
    end
end
display();

while true do
    local senderId, message, protocol = rednet.receive();
    messageIndex = messageIndex + 1;
    message[messageIndex] = {
        senderId = senderId,
        message = message,
        protocol = protocol
    };
    display();
end