#include <ESP32Servo.h>
#include "DHTesp.h"
#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>
#include "ThingSpeak.h"
#include <WiFi.h>

#define SCREEN_WIDTH 128
#define SCREEN_HEIGHT 64

Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, -1);

const int esp_id = 1;

const int sprinkerPin1 = 18;
const int sprinkerPin2 = 19;
const int ldrPin = 12;
const int dhtPin = 15;
const int buzzPin = 13;

DHTesp dhtSensor;

Servo sprinkler1, sprinkler2;

unsigned long lastTime = 0;
unsigned long sprinkerFreq = 5000;

int pos = 0;

const float GAMMA = 0.7;
const float RL10 = 50;

const char* myWriteAPIKey = "R839LJWPBAK87L9B";
const char* server = "api.thingspeak.com";
unsigned long myChannelNumber = 1;
const char* ssid = "Wokwi-GUEST";
const char* pass = "";

WiFiClient client;

void setup() {

  // put your setup code here, to run once:
  if(!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) {
  Serial.println(F("SSD1306 allocation failed"));
  for(;;);
  }
  delay(2000);

  Serial.begin(115200);
  sprinkler1.attach(sprinkerPin1, 500, 2400);
  sprinkler2.attach(sprinkerPin2, 500, 2400); 

  sprinkler1.write(90);
  sprinkler2.write(90);

  dhtSensor.setup(dhtPin, DHTesp::DHT22);

  pinMode(buzzPin, OUTPUT);
  pinMode(ldrPin, INPUT);

  WiFi.begin(ssid, pass);
  Serial.println("WiFi Connecting");
  while(WiFi.status() != WL_CONNECTED) {
    delay(100);
    Serial.print(".");
  }
  Serial.println("WiFi Connected!");
  Serial.println(WiFi.localIP());
  ThingSpeak.begin(client);
  
  WiFi.mode(WIFI_STA);
}

void loop() {
  int analogValue = analogRead(ldrPin);
  float voltage = analogValue / 1024. * 5;
  float resistance = 2000 * voltage / (1 - voltage / 5);
  float lux = pow(RL10 * 1e3 * pow(10, GAMMA) / resistance, (1 / GAMMA));

 
  if(lux > 230) {
    if ((millis() - lastTime) > sprinkerFreq) {
      sprinklerActivate();
      lastTime = millis();
    }
  }

  TempAndHumidity data = dhtSensor.getTempAndHumidity();
  Serial.println("Temp: " + String(data.temperature, 2) + "°C");
  Serial.println("Humidity: " + String(data.humidity, 1) + "%");
  Serial.println("Lux:" + String(lux, 2));
  ThingSpeak.setField(1, data.temperature);
  ThingSpeak.setField(2, data.humidity);
  ThingSpeak.setField(3, lux);

  int x = ThingSpeak.writeFields(myChannelNumber, myWriteAPIKey);
  if (x == 200) {
    Serial.println("Channel update successful.");
  }
  else{
    Serial.println("Problem updating channel. HTTP error code " + String(x));
  }
  
  if(data.temperature > 50 && data.humidity < 30) {
    sprinklerActivate();
    lastTime = millis();
  }
  delay(100);
  oled_display("");
}

void sprinklerActivate() {
  oled_display("Sprinkler running");
  tone(buzzPin, 500, 500);
  for (pos = 0; pos <= 180; pos += 1) {
    sprinkler1.write(pos);
    sprinkler2.write(pos);
    delay(15);
  }
  sprinkler1.write(90);
  sprinkler2.write(90);
}

void oled_display(String msg) {
  display.clearDisplay();
  display.setTextSize(1);
  display.setTextColor(WHITE);
  display.setCursor(20, 10);
  display.println(msg);
  display.display(); 
}