My ComputerCraft BBS cilent/server

bbs.lua

ARGS = {...}
COLORCTL = string.char(3)

HOMESCREEN = {
    screen = "hello, world!",
    click = function(x,y) end,
    line = function(str) end
}

function log(chan, msg)
    if true then
        print(chan, msg)
    end
end

function announce()
    rednet.broadcast("TIFFNET Tiffany's BBS")
    os.startTimer(30)
end

announce()

clients = {}

function updateScreen(client)
    rednet.send(client, "SCREEN "..tostring(clients[client].screen.screen))
end

function accept(sender, message, dist)
    if message == "CONNECT" then
        clients[sender] = {screen = HOMESCREEN, x = 0, y = 0};
        updateScreen(sender)
        print("New client from "..sender);
    end
end

function handleMsg(sender, message, dist)
    log(sender, message)
    if message:sub(1,5) == "CLICK" then
        local x, y = message:match("CLICK (%d+) (%d+)");
        clients[sender].x = tonumber(x);
        clients[sender].y = tonumber(y);
        clients[sender].screen.click(tonumber(x), tonumber(y));
    elseif message:sub(1,4) == "LINE" then
        local str = message:sub(6, -1);
        clients[sender].screen.line(str);
    elseif message:sub(1,10) == "DISCONNECT" then
        clients[sender] = nil;
        print("Goodbye, "..sender);
    end
end

function main()
    if #ARGS < 1 then
        print "Usage: bbs <side>"
        return;
    end
    rednet.open(ARGS[1])
    while true do
        local args = {os.pullEventRaw()};
        --print("Event:",unpack(args));
        local ev = args[1];
        if ev == "rednet_message" then
            local _, sender, message, dist = unpack(args);
            if clients[sender] == nil then
                accept(sender, message, dist)
            else
                handleMsg(sender, message, dist)
            end
        elseif ev == "timer" then
            announce()
        end
    end
end

main()

tiffnet.lua

COLORCTL = string.char(3);

servers = {}
selected = 1;
offset = 1;
current_server = nil

function log(msg)
    if false then
        rednet.broadcast("DEBUG "..msg)
    end
end

function connect(s)
    current_server = s;
    if not s then
        error "No server to connect to!"
    end
    local id = s.id;
    screen = "Connecting...";
    rednet.send(id, "CONNECT");
    while server() do
        term.setBackgroundColor(colors.black)
        term.setTextColor(colors.white)
        term.clear()
        draw_server();
    end
end

screen = ""

function isColor(c)
    return c == COLORCTL
end

function decodeColor(str)
    if not isColor(str:sub(1,1)) then return 1, 32768, 0; end;
    local f, b, o1, o2 = str:match(COLORCTL .. "(%d+),()?(%d*)()");
    if not f then f = 1 end
    if not b then b = 32768 end
    return f,b, o2 or o1 or 0;
end

function draw_server()
    local w,h = term.getSize()
    for i = 1, #screen do
        if isColor(screen:sub(i,i)) then
            local f, b, o = decodeColor(screen:sub(i,-1))
            term.setTextColor(2^f)
            term.setBackgroundColor(2^b)
            i = i + o
        end
        term.write(screen:sub(i,i))
        term.setCursorPos(i%w + 1, math.floor(i/h) + 1)
    end
end

function servermsg(sender, message, dist)
    if sender ~= current_server.id then return; end
    if message:sub(1,6) == "SCREEN" then
        screen = message:sub(7,-1)
    end
end

server_str = "";
function server()
    local args = {os.pullEventRaw()};
    if args[1] == "mouse_click" then
        rednet.send(current_server.id, "CLICK "..tostring(args[2])..tostring(args[3]))
    elseif args[1] == "char" then
        server_str = server_str .. args[2];
    elseif args[1] == "key" then
        if args[2] == 28 then -- enter
            rednet.send(current_server.id, "LINE "..server_str);
            server_str = "";
        elseif args[2] == 14 then -- backspace
            rednet.send(current_server.id, "DISCONNECT");
            current_server = nil;
            return false;
        end
    elseif args[1] == "rednet_message" then
        servermsg(args[2], args[3], args[4])
    end
    return true;
end

function rednet_message(sender, message, dist)
    if message:sub(1,7) == "TIFFNET" then
        servers[sender] = {id = sender, description = message:sub(9, -1), distance = dist};
    end
end

function draw_list()
    term.setBackgroundColor(colors.black)
    term.clear()
    local i = offset;
    local w,h = term.getSize();
    if selected > offset+h+1 then
        offset = selected-h-1
    elseif selected < offset+1 then
        offset = selected-1
    end
    offset = math.min(offset, #servers - h)
    offset = math.max(offset, 0)
    term.setCursorPos(1, 1)
    term.setTextColor(colors.white)
    term.setBackgroundColor(colors.blue)
    term.clearLine()
    term.setCursorPos(1, 1)
    term.write("ID   Description")
    term.setCursorPos(w-5, 1)
    term.write("Dist ")
    term.setBackgroundColor(colors.black)
    for k, v in pairs(servers) do
        i = i + 1;
        if i > offset+h then
            break;
        end
        term.setCursorPos(1, i+1)
        if i == selected then
            term.setBackgroundColor(colors.gray)
            term.clearLine()
        else
            term.setBackgroundColor(colors.black)
        end
        log("Drawing server "..k.." at "..i.." (offset "..offset..")")
        term.setCursorPos(1, i+1)
        term.write(tostring(k))
        term.setCursorPos(5, i+1)
        term.write(v.description)
        term.setCursorPos(w-5, i+1)
        term.write(v.distance)
    end
    term.setBackgroundColor(colors.black)
end

function list()
    local args = {os.pullEventRaw()};
    local event = args[1];
    if event == "char" then
        if args[2] == "q" then
            return false
        end
    elseif event == "key" then
        if args[2] == 200 then -- up
            selected = selected - 1;
            if selected < 1 then selected = 1 end
        elseif args[2] == 208 then -- down
            selected = selected + 1;
            if selected > #servers then selected = #servers end
        elseif args[2] == 28 then -- enter
            local i = 0;
            log("selected: "..selected)
            for k,v in pairs(servers) do
                i = i+1
                log(i.." "..k.." "..tostring(v))
                if i == selected then
                    connect(v)
                end
            end
        end
    elseif event == "mouse_scroll" then
        selected = selected + args[4];
    elseif event == "rednet_message" then
        rednet_message(args[2], args[3], args[4])
    end
    return true;
end

arg = {...}

function main()
    if #arg < 1 then
        print "Usage: tiffnet <side>"
        return;
    end
    rednet.open(arg[1]);
    draw_list();
    while list() do 
        draw_list()
    end
    rednet.close(arg[1]);
    term.clear()
    term.setCursorPos(1,1)
end

main()

tiffnet.md

Tiffnet 0.0.1 Protocol

States Connected, Disconnected

Scope: Individual relationship between a client and a server.

Server Messages:

TIFFNET <description>

Broadcasts the server to disconnected clients. State: Any (Use multicast or similar for this message)

SCREEN <message>

Sets the screen of a client. State: Connected

Client messages:

CONNECT

Sets the state from Disconnected to Connected. State: Disconnected

CLICK <x> <y>

Should correspond to a mouse click event on the client's screen. State: Connected

LINE <message>

Should correspond to a user entering text and hitting ENTER or RETURN. State: Connected

DISCONNECT

Sets the state from Connected to Disconnected. State: Connected