#include <WiFi.h>
#include "PubSubClient.h"
#include <Keypad.h>

const char * MQTTServer = "broker.hivemq.com";
const char * MQTT_Topic = "Keypass";

// Tạo ID ngẫu nhiên tại: https://www.guidgen.com/
const char * MQTT_ID = "thachlai";
int Port = 1883;
#define BUZZER_PIN  22
#define ROW_NUM     4  // four rows
#define COLUMN_NUM  4  // four columns
String MK;

WiFiClient espClient;
PubSubClient client(espClient);

void WIFIConnect() {
  Serial.println("Connecting to SSID: Wokwi-GUEST");
  WiFi.begin("Wokwi-GUEST", "");
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
  Serial.println("");
  Serial.print("WiFi connected");
  Serial.print(", IP address: ");
  Serial.println(WiFi.localIP());
}

void MQTT_Reconnect() {
  while (!client.connected()) {
    if (client.connect(MQTT_ID)) {
      Serial.print("MQTT Topic: ");
      Serial.print(MQTT_Topic);
      Serial.print(" connected");
      client.subscribe(MQTT_Topic);
      Serial.println("");
    } else {
      Serial.print("failed, rc=");
      Serial.print(client.state());
      Serial.println(" try again in 5 seconds");
      delay(5000);
    }
  }
}

void callback(char* topic, byte* message, unsigned int length) {
  Serial.print("Message arrived on topic: ");
  Serial.println(topic);
  Serial.print("Message: ");
  String stMessage;

  for (int i = 0; i < length; i++) {
    Serial.print((char)message[i]);
    stMessage += (char)message[i];
  }
  Serial.println();
  if (stMessage == "Đúng") {
    digitalWrite(BUZZER_PIN, HIGH);
    digitalWrite(BUZZER_PIN, LOW);
  }
  else if (stMessage == "Sai") {
    digitalWrite(BUZZER_PIN, HIGH);
    digitalWrite(BUZZER_PIN, LOW);
    vTaskDelay(100);
    digitalWrite(BUZZER_PIN, HIGH);
    digitalWrite(BUZZER_PIN, LOW);
    vTaskDelay(100);
    digitalWrite(BUZZER_PIN, HIGH);
    digitalWrite(BUZZER_PIN, LOW);
  }
}

char keys[ROW_NUM][COLUMN_NUM] = {
  {'1', '2', '3', 'A'},
  {'4', '5', '6', 'B'},
  {'7', '8', '9', 'C'},
  {'*', '0', '#', 'D'}
};

byte pin_rows[ROW_NUM] = {19, 18, 5, 21};    // GIOP19, GIOP18, GIOP5, GIOP17 connect to the row pins
byte pin_column[COLUMN_NUM] = {23, 13, 12, 14}; // GIOP16, GIOP4, GIOP0, GIOP2 connect to the column pins

Keypad keypad = Keypad(makeKeymap(keys), pin_rows, pin_column, ROW_NUM, COLUMN_NUM );

void setup() {
  Serial.begin(115200);
  WIFIConnect();
  client.setServer(MQTTServer, Port);
  client.setCallback(callback);
  pinMode(BUZZER_PIN, OUTPUT);
}

void loop() {
  delay(10);
  if (!client.connected()) {
    MQTT_Reconnect();
  }
  client.loop();
  char key = keypad.getKey();
  if (key == '#') {
    String input = "{\"Mật Khẩu\":\"" + MK + "\"}";
    client.publish(MQTT_Topic,String(input).c_str());
    Serial.println(MK);
    MK="";
  }
  if (key == '1'||key == '2'||key == '3'||key == '4'||key == '5'||key == '6'||key == '7'||key == '8'||key == '9'||key == '0') {
    MK += key;
  }
}