// From https://randomnerdtutorials.com/esp32-mqtt-publish-subscribe-arduino-ide
 
#include <time.h>
#include <stdlib.h>
#include <WiFi.h>
#include "PubSubClient.h"
#include <ESP32Servo.h>
#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>

#define SCREEN_WIDTH 128 // OLED display width, in pixels
#define SCREEN_HEIGHT 64 // OLED display height, in pixels

const char* ssid = "Wokwi-GUEST";
const char* password = "";
const char* mqttServer = "broker.emqx.io";
String stMac;
char mac[50];
char clientId[50];
const int servoPin1 = 12;
Servo servo1;
const int servoPin2 = 4;
Servo servo2;
const int servoPin3 = 15;
Servo servo3;

WiFiClient espClient;
PubSubClient client(espClient);


const int ledPin1 = 4;
const int ledPin2 = 12;
const int ledPin3 = 13;
const int ledPin4 = 5;



// Declaration for an SSD1306 display connected to I2C (SDA, SCL pins)
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, 1);


void setup() {
  Serial.begin(115200);
  servo1.attach(servoPin1, 500, 2400);
  servo2.attach(servoPin2, 500, 2400);
  servo3.attach(servoPin3, 500, 2400);
  if(!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) { // Address 0x3D for 128x64
    Serial.println(F("SSD1306 allocation failed"));
    for(;;);
  }
  delay(2000);
  display.clearDisplay();




  srand(time(NULL));
  rand();
  
  delay(10);
  Serial.println();
  Serial.print("Connecting to ");
  Serial.println(ssid);

  wifiConnect();
  
  client.setServer(mqttServer, 1883);
  client.setCallback(callback);
  pinMode(ledPin1, OUTPUT);
  pinMode(ledPin2, OUTPUT);
  pinMode(ledPin3, OUTPUT);
  pinMode(ledPin4, OUTPUT);
}

void wifiConnect() {
  WiFi.mode(WIFI_STA);
  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
}

void mqttReconnect() {
  while (!client.connected()) {
    Serial.print("Attempting MQTT connection...");
    int r = rand();
    sprintf(clientId, "clientId-%d", r);
    // client.connect(clientId);
    // Serial.print(clientId);
    // Serial.println(" connected");
    client.subscribe("topicName/led");
    if (client.connect(clientId)) {
      Serial.print(clientId);
      Serial.println(" connected");
      client.subscribe("topicName/led");
    } 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.print(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 (String(topic) == "topicName/led") {
    Serial.print("Changing output to ");
    if(stMessage == "1"){
      Serial.println("1");
      display.clearDisplay();
      display.setTextSize(1);
      display.setTextColor(WHITE);
      display.setCursor(10, 0);
      // Display static text
      display.println("Release Orbital Access Arm");
      display.display(); 
      servo1.write(180);
      


    }
    else if(stMessage == "2"){
      Serial.println("2");
      digitalWrite(ledPin1, HIGH);
      display.clearDisplay();
      display.setTextSize(1);
      display.setTextColor(WHITE);
      display.setCursor(10, 0);
      // Display static text
      display.println("Main engine gimbal test and lift beanie Cap");
      display.display(); 
      servo2.write(0);
    }
    else if(stMessage == "3"){
      Serial.println("3");
      digitalWrite(ledPin2, HIGH);
      display.clearDisplay();
      display.setTextSize(1);
      display.setTextColor(WHITE);
      display.setCursor(10, 0);
      // Display static text
      display.println("Activate Hydrogen Burn off system");
      display.display(); 
    }
    else if(stMessage == "4"){
      Serial.println("4");
      digitalWrite(ledPin3, HIGH);
      display.clearDisplay();
      display.setTextSize(1);
      display.setTextColor(WHITE);
      display.setCursor(10, 0);
      // Display static text
      display.println("Main engine ignite");
      display.display(); 
      
    }
    else if(stMessage == "5"){
      Serial.println("5");
      servo3.write(360);
      display.clearDisplay();
      display.setTextSize(1);
      display.setTextColor(WHITE);
      display.setCursor(10, 0);
      // Display static text
      display.println("Hydrogen vent Arm | Release tail surface mass | Detonate hold-down bolts");
      display.display(); 
      
    }
    else if(stMessage == "6"){
      Serial.println("6");
      digitalWrite(ledPin4, HIGH);
      display.clearDisplay();
      display.setTextSize(1);
      display.setTextColor(WHITE);
      display.setCursor(10, 0);
      // Display static text
      display.println("Ignite Both SRBs");
      display.display(); 
      
    }
  }
}

void loop() {
  delay(10);
  if (!client.connected()) {
    mqttReconnect();
  }
  client.loop();
}