+function bus_app(req, res) {
+ res.sendFile(__dirname + '/bus.html');
+}
+
+app.get('/bus', bus_app);
+app.get('/bus/', bus_app);
+
+const io_bus = io.of("/bus");
+
+io_bus.use(wrap(session_middleware));
+
+var bus_interval = 0;
+
+function start_bus() {
+ const bus = state.bus;
+
+ bus.state = "program";
+
+ // Let all companions know the state of the game
+ io_bus.emit("state", bus.state);
+}
+
+function emit_bus_timer() {
+ const bus = state.bus;
+ io_bus.emit('timer', bus.timer);
+ bus.timer = bus.timer - 1;
+ if (bus.timer < 0) {
+ clearInterval(bus_interval);
+ bus.timer = 30;
+ setTimeout(start_bus, 3000);
+ }
+}
+
+function start_bus_timer() {
+ const bus = state.bus;
+ bus.timer = 30;
+ emit_bus_timer();
+ bus_interval = setInterval(emit_bus_timer, 1000);
+}
+
+bus_code = [
+ `def random_dot():
+ x = random_within(512)
+ y = random_within(512)
+ radius = 4 + random_within(6)
+ circle(x, y, radius)
+ fill()
+
+for i in range(400):
+ set_color('midnight blue' if i % 2 == 0 else 'navy blue')
+ set_opacity(0.5)
+ random_dot()
+
+# The only limit is your fingers!
+fingers()`,
+
+ `def random_line():
+ x = random_within(512) - 60
+ y = random_within(512) - 60
+ dx = 60 + random_within(20)
+ dy = 40 + random_within(20)
+ set_opacity(random_within(0.5))
+ line(x, y, dx, dy)
+ stroke()
+
+for i in range(200):
+ set_color('black')
+ random_line()
+
+# This is Zombo.com. Welcome!
+mouths()`,
+
+ `def random_blob():
+ move_to(random_within(512), random_within(512))
+ wiggle()
+ set_opacity(random_within(1.0))
+ fill()
+
+for i in range(100):
+ set_random_color()
+ random_blob()
+
+# The infinite eyes is possible!
+eyes()`,
+
+ `def random_curve():
+ move_to(random_within(512), random_within(512))
+ wiggle()
+ stroke()
+
+for i in range(200):
+ set_color('pink' if i % 2 == 0 else 'lime green')
+ random_curve()
+
+# You can do anything!
+fingers()
+`
+];
+
+io_bus.on("connection", (socket) => {
+ if (! socket.request.session.name) {
+ console.log("Error: Someone showed up at the Magic School Bus without a name.");
+ return;
+ }
+
+ const name = socket.request.session.name;
+ const bus = state.bus;
+ var player_number;
+
+ // Let the new user know the state of the bus
+ socket.emit("state", bus.state);
+
+ if (bus.students.count === 0) {
+ start_bus_timer();
+ }
+
+ // Assign each boy a different portion of the solution
+ switch (name[0]) {
+ case 'C':
+ case 'c':
+ player_number = 0;
+ break;
+ case 'H':
+ case' h':
+ player_number = 1;
+ break;
+ case 'A':
+ case 'a':
+ player_number = 2;
+ break;
+ case 'S':
+ case 's':
+ player_number = 3;
+ break;
+ default:
+ player_number = Math.floor(Math.random()*4);
+ break;
+ }
+
+ // And send them different code based on their number
+ socket.emit("code", bus_code[player_number]);
+
+ if (! bus.students.names.includes(name)) {
+ bus.students.count = bus.students.count + 1;
+ io_bus.emit('students', bus.students.count);
+ }
+ bus.students.names.push(name);
+
+ socket.on('run', code => {
+ try {
+ output = child_process.execFileSync(python_path, [interpret_cairo_script, player_number], { input: code });
+ // Grab just first line of output
+ const nl = output.indexOf("\n");
+ if (nl === -1)
+ nl = undefined;
+ const filename = output.toString().substring(0, nl);
+
+ // Give all clients the new image
+ io_bus.emit('output', filename);
+ } catch (e) {
+ // Send any error out to the users
+ io_bus.emit('error', e.toString())
+ }
+ });
+
+ socket.on('jumpstart', () => {
+ const bus = state.bus;
+
+ bus.state = "welcome";
+ io_bus.emit("state", bus.state);
+ io_bus.emit('students', bus.students.count);
+
+ start_bus_timer();
+ });
+
+ socket.on('disconnect', () => {
+ const names = bus.students.names;
+
+ names.splice(names.indexOf(name), 1);
+
+ if (! names.includes(name)) {
+ bus.students.count = bus.students.count - 1;
+ io_bus.emit('students', bus.students.count);
+ }
+ });
+});
+