Implement logging in via touch code

arduino/arduino.ino

@@ -1,10 +1,21 @@
 #include <Arduino_MKRIoTCarrier.h>
 #include <WiFiNINA.h>
 #include <ArduinoMqttClient.h>
-#include "state.h"
 #include "motor.h"
 #include "secrets.h"
 
+#define INPUT_SIZE 4
+
+enum state {
+	STATE_CONNECTING,
+	STATE_LOGGED_OUT,
+	STATE_LOGGED_IN,
+	STATE_INPUT_PASSCODE,
+};
+
+enum state current_state;
+char input_code[INPUT_SIZE + 1];
+
 MKRIoTCarrier carrier;
 WiFiSSLClient wifi_client;
 MqttClient mqtt_client(wifi_client);
@@ -15,6 +26,87 @@ int motor_count_max = 64;
 
 uint32_t green_led_color = carrier.leds.Color(0, 255, 0);
 
+bool is_input_empty()
+{
+	for (int i = 0; i < INPUT_SIZE; i++) {
+		if (input_code[i]) return false;
+	}
+	return true;
+}
+
+bool is_input_full()
+{
+	for (int i = 0; i < INPUT_SIZE; i++) {
+		if (!input_code[i]) return false;
+	}
+	return true;
+}
+
+void change_state(enum state new_state)
+{
+	// Initialize state
+	switch (new_state) {
+		case STATE_INPUT_PASSCODE:
+			input_code[0] = '\0';
+			input_code[1] = '\0';
+			input_code[2] = '\0';
+			input_code[3] = '\0';
+			input_code[4] = '\0';
+			break;
+	}
+
+	current_state = new_state;
+	draw_state();
+}
+
+void draw_state()
+{
+	carrier.display.fillScreen(0x000);
+
+	switch (current_state) {
+		case STATE_CONNECTING:
+			carrier.display.setCursor(20, 100);
+			carrier.display.setTextSize(3);
+			carrier.display.print("Connecting..");
+			break;
+
+		case STATE_LOGGED_OUT:
+			carrier.display.setCursor(15, 100);
+			carrier.display.setTextSize(2);
+			carrier.display.print("Press Green Button");
+			carrier.leds.fill(green_led_color, 2, 1);
+			carrier.leds.setBrightness(5);
+			carrier.leds.show();
+			break;
+
+		case STATE_INPUT_PASSCODE:
+			if (is_input_empty()) {
+				carrier.display.setCursor(50, 100);
+				carrier.display.setTextSize(2);
+				carrier.display.print("Please enter");
+				carrier.display.setCursor(80, 120);
+				carrier.display.print("passcode");
+			} else {
+				carrier.display.setCursor(50, 100);
+				carrier.display.setTextSize(3);
+				for (int i = 0; i < INPUT_SIZE; i++) {
+					char ch = input_code[i];
+					if (!ch) ch = '_';
+
+					carrier.display.print(ch);
+					carrier.display.print(' ');
+				}
+			}
+			break;
+
+		case STATE_LOGGED_IN:
+			carrier.display.setCursor(40, 100);
+			carrier.display.setTextSize(3);
+			carrier.display.print("Logged in");
+			break;
+	}
+}
+
 void setup()
 {
 	Serial.begin(9600);
@@ -54,6 +146,7 @@ void setup()
 	carrier.Buzzer.beep();
 
 	mqtt_client.subscribe("dispense");
+	mqtt_client.subscribe("login");
 
 	change_state(STATE_LOGGED_OUT);
 }
@@ -71,16 +164,71 @@ void loop()
 	// Receive MQTT messages
 	int message_size = mqtt_client.parseMessage();
 	if (message_size) {
+		String topic = mqtt_client.messageTopic();
 		Serial.print("Got message with topic: ");
-		Serial.println(mqtt_client.messageTopic());
+		Serial.println(topic);
 
-		if (mqtt_client.messageTopic() == "dispense") {
+		// Parse message
+		char *message = (char *)malloc(message_size + 1);
+		for (int i = 0; i < message_size && mqtt_client.available(); i++) {
+			message[i] = (char)mqtt_client.read();
+		}
+		message[message_size] = '\0';
+
+		Serial.print("and payload: ");
+		Serial.println(message);
+
+		// Check topic
+		if (topic == "dispense") {
 			Serial.println("Dispensing...");
 
 			// Start rotating motor
 			motor_count = motor_count_max;
+		} else if (topic == "login") {
+			Serial.println("Logged in");
+
+			int user_id;
+			if (sscanf(message, "%d", &user_id) > 0) {
+				change_state(STATE_LOGGED_IN);
+			} else {
+				change_state(STATE_INPUT_PASSCODE);
+			}
 		}
+
+		free(message);
 	}
 
-	loop_state();
+	switch (current_state) {
+		case STATE_LOGGED_OUT:
+			if (carrier.Buttons.onTouchDown(TOUCH2)) {
+				change_state(STATE_INPUT_PASSCODE);
+			}
+			break;
+		case STATE_INPUT_PASSCODE:
+			touchButtons buttons[] = { TOUCH0, TOUCH1, TOUCH3, TOUCH4 };
+			char input_characters[] = "1234";
+
+			for (int i = 0; i < sizeof(buttons) / sizeof(buttons[0]); i++) {
+				if (carrier.Buttons.onTouchDown(buttons[i])) {
+					for (int j = 0; j < INPUT_SIZE; j++) {
+						if (!input_code[j]) {
+							input_code[j] = input_characters[i];
+							break;
+						}
+					}
+
+					if (is_input_full()) {
+						mqtt_client.beginMessage("login_request");
+						mqtt_client.print(input_code);
+						mqtt_client.endMessage();
+					}
+
+					draw_state();
+
+					break;
+				}
+			}
+
+			break;
+	}
 }

arduino/state.h

@@ -1,9 +0,0 @@
-enum state {
-  STATE_CONNECTING,
-  STATE_LOGGED_OUT,
-  STATE_LOGGED_IN,
-  STATE_INPUT_PASSCODE,
-};
-
-void change_state(enum state new_state);
-void loop_state();

arduino/state.ino

@@ -1,101 +0,0 @@
-#define INPUT_SIZE 4
-
-enum state current_state;
-char input_code[INPUT_SIZE];
-
-bool is_input_empty()
-{
-	for (int i = 0; i < INPUT_SIZE; i++) {
-		if (input_code[i]) return false;
-	}
-	return true;
-}
-
-void change_state(enum state new_state)
-{
-	// Initialize state
-	switch (new_state) {
-		case STATE_INPUT_PASSCODE:
-			input_code[0] = '\0';
-			input_code[1] = '\0';
-			input_code[2] = '\0';
-			input_code[3] = '\0';
-			break;
-	}
-
-	current_state = new_state;
-	draw_state();
-}
-
-void draw_state()
-{
-	carrier.display.fillScreen(0x000);
-
-	switch (current_state) {
-		case STATE_CONNECTING:
-			carrier.display.setCursor(20, 100);
-			carrier.display.setTextSize(3);
-			carrier.display.print("Connecting..");
-			break;
-
-		case STATE_LOGGED_OUT:
-			carrier.display.setCursor(15, 100);
-			carrier.display.setTextSize(2);
-			carrier.display.print("Press Green Button");
-			carrier.leds.fill(green_led_color, 2, 1);
-			carrier.leds.setBrightness(5);
-			carrier.leds.show();
-			break;
-		case STATE_INPUT_PASSCODE:
-			if (is_input_empty()) {
-				carrier.display.setCursor(50, 100);
-				carrier.display.setTextSize(2);
-				carrier.display.print("Please enter");
-				carrier.display.setCursor(80, 120);
-				carrier.display.print("passcode");
-			} else {
-				carrier.display.setCursor(50, 100);
-				carrier.display.setTextSize(3);
-				for (int i = 0; i < INPUT_SIZE; i++) {
-					char ch = input_code[i];
-					if (!ch) ch = '_';
-
-					carrier.display.print(ch);
-					carrier.display.print(' ');
-				}
-			}
-			break;
-	}
-}
-
-void loop_state()
-{
-	switch (current_state) {
-		case STATE_LOGGED_OUT:
-			if (carrier.Buttons.onTouchDown(TOUCH2)) {
-				change_state(STATE_INPUT_PASSCODE);
-			}
-			break;
-		case STATE_INPUT_PASSCODE:
-			touchButtons buttons[] = { TOUCH0, TOUCH1, TOUCH3, TOUCH4 };
-			char input_characters[] = "1234";
-
-			for (int i = 0; i < sizeof(buttons) / sizeof(buttons[0]); i++) {
-				if (carrier.Buttons.onTouchDown(buttons[i])) {
-					
-					for (int j = 0; j < sizeof(input_code); j++) {
-						if (!input_code[j]) {
-							input_code[j] = input_characters[i];
-							break;
-						}
-					}
-
-					draw_state();
-
-					break;
-				}
-			}
-
-			break;
-	};
-}

backend/Program.cs

@@ -49,9 +49,39 @@ var options = new MqttClientOptionsBuilder()
 
 await mqttClient.ConnectAsync(options, CancellationToken.None);
 
-ApplicationState.MqttClient = mqttClient;
+await mqttClient.SubscribeAsync(
+	new MqttFactory().CreateSubscribeOptionsBuilder().WithTopicFilter(f => f.WithTopic("login_request")).Build(),
+	CancellationToken.None
+);
+
 ApplicationState.DbContext = new DispenserContext();
 
+mqttClient.ApplicationMessageReceivedAsync += delegate(MqttApplicationMessageReceivedEventArgs args) {
+	var payload = System.Text.Encoding.Default.GetString(args.ApplicationMessage.PayloadSegment);
+
+	switch (args.ApplicationMessage.Topic) {
+		case "login_request":
+			var user = ApplicationState.DbContext!.Users.FirstOrDefault(user => user.TouchCode == payload);
+
+			var message = new MqttApplicationMessageBuilder()
+					.WithTopic("login");
+
+			if (user == null) {
+				message.WithPayload("error");
+			} else {
+				message.WithPayload(user.Id.ToString());
+			}
+
+			mqttClient.PublishAsync(message.Build());
+
+			break;
+	}
+
+	return Task.CompletedTask;
+};
+
+ApplicationState.MqttClient = mqttClient;
+
 Console.WriteLine("Connected");
 
 app.Run();