#include <WiFi.h>
#include <PubSubClient.h>
#include <LiquidCrystal_I2C.h>
#include <ThingSpeak.h>

long myChannelNumber = 2770711;
const char * myWriteAPIKey = "ZFRFXYC5JCVSOD93";
// WiFi
const char *ssid = "Wokwi-GUEST"; // Enter your Wi-Fi name
const char *password = "";  // Enter Wi-Fi password

// MQTT Broker
const char *mqtt_broker = "broker.emqx.io";
const char *topic = "/water vending/machine/123";
const char *mqtt_username = "emqx";
const char *mqtt_password = "public";
const int mqtt_port = 1883;

#define BUTTON_PIN 12 // GIOP12 pin connected to button
int button_state;       // the current state of button
int last_button_state;  // the previous state of button

#define MOTOR1 34
#define MOTOR2 35

#define SPEAKER 18

int count = 0;

WiFiClient espClient;
PubSubClient client(espClient);

LiquidCrystal_I2C lcd(0x27,16,2);

void setup() {
    // Set software serial baud to 115200;
    Serial.begin(115200);

    pinMode(SPEAKER, OUTPUT);
    digitalWrite(SPEAKER, LOW);

    pinMode(MOTOR1, OUTPUT);
    pinMode(MOTOR2, OUTPUT);
    digitalWrite(MOTOR1, HIGH);
    digitalWrite(MOTOR2, HIGH);
    
    pinMode(BUTTON_PIN, INPUT_PULLUP);
    button_state = digitalRead(BUTTON_PIN);

    lcd.init();
    lcd.clear();         
    lcd.backlight();

    lcd.setCursor(1,0);   //Set cursor to character 2 on line 0
    lcd.print("Connecting to");
    lcd.setCursor(1,1);   //Set cursor to character 2 on line 0
    lcd.print("Internet...");

    // Connecting to a WiFi network
    WiFi.begin(ssid, password);
    while (WiFi.status() != WL_CONNECTED) {
        delay(500);
        Serial.println("Connecting to WiFi..");
    }
    Serial.println("Connected to the Wi-Fi network");
    //connecting to a mqtt broker
    client.setServer(mqtt_broker, mqtt_port);
    
    while (!client.connected()) {
        String client_id = "esp32-client-";
        client_id += String(WiFi.macAddress());
        Serial.printf("The client %s connecting to the public MQTT broker.....\n", client_id.c_str());
        if (client.connect(client_id.c_str(), mqtt_username, mqtt_password)) {
            Serial.println("Public EMQX MQTT broker connected");
        } else {
            Serial.print("failed with state ");
            Serial.print(client.state());
            delay(2000);
        }
    }

    lcd.clear();
    lcd.setCursor(1,0);   //Set cursor to character 2 on line 0
    lcd.print("please insert coin");
    lcd.setCursor(1,1);   //Move cursor to character 2 on line 1
    lcd.print("0");
    // client.publish(topic, "1");
}

void loop() {
  client.loop();
  
  last_button_state = button_state;      // save the last state
  button_state = digitalRead(BUTTON_PIN); // read new state

  if (last_button_state == HIGH && button_state == LOW) {
    Serial.println("The button is pressed, ");
    count += 1;
    lcd.setCursor(1,1);
    lcd.print("                ");
    delay(10);
    lcd.setCursor(1,1);
    lcd.print(String(count));
    client.publish(topic, "1");
    digitalWrite(SPEAKER, HIGH);
    digitalWrite(MOTOR1, LOW);
    digitalWrite(MOTOR2, LOW);
    delay(2000);
    digitalWrite(SPEAKER, LOW);
    digitalWrite(MOTOR1, HIGH);
    digitalWrite(MOTOR2, HIGH);
ThingSpeak.setField(1,MOTOR1);
ThingSpeak.setField(2,MOTOR2);
ThingSpeak.setField(3,SPEAKER);
  }

}