#include <Arduino.h>
#include "EmonLib.h"
#include "WiFi.h"
#include <driver/adc.h>
#include <PubSubClient.h>


// This is the device name as defined on AWS IOT
#define DEVICE_NAME "xd-home-energy-monitor-1"

// The GPIO pin were the CT sensor is connected to (should be an ADC input)
#define ADC_INPUT 34

// The voltage in our apartment. Usually this is 230V for Europe, 110V for US.
// Ours is higher because the building has its own high voltage cabin.
#define HOME_VOLTAGE 110.0

// Force EmonLib to use 10bit ADC resolution
#define ADC_BITS    10
#define ADC_COUNTS  (1<<ADC_BITS)

// Create instances
EnergyMonitor emon1;

// Wifi credentials
const char *WIFI_SSID = "Xiaomi_Router";
const char *WIFI_PASSWORD = "UYQQMTHF";
const char* mqtt_server = "m21.cloudmqtt.com";

WiFiClient lolinClient;
PubSubClient client(lolinClient);
char message_buff[100];

// Array to store 30 readings (and then transmit in one-go to AWS)
short measurements[30];
short measureIndex = 0;
unsigned long lastMeasurement = 0;
unsigned long timeFinishedSetup = 0;

void setup()
{
  Serial.begin(115200);
  adc1_config_channel_atten(ADC1_CHANNEL_6, ADC_ATTEN_DB_11);
  analogReadResolution(10);

  connectToWiFi();

  // Initialize emon library (30 = calibration number)
  emon1.current(ADC_INPUT, 30);

  timeFinishedSetup = millis();
  client.setServer(mqtt_server, 18932);
}

void connectToWiFi() {
  WiFi.begin(WIFI_SSID, WIFI_PASSWORD);

  // Only try 15 times to connect to the WiFi
  int retries = 0;
  while (WiFi.status() != WL_CONNECTED && retries < 15) {
    delay(500);
    Serial.print(".");
    retries++;
  }

  // If we still couldn't connect to the WiFi, go to deep sleep for a
  // minute and try again.
  if (WiFi.status() != WL_CONNECTED) {
    esp_sleep_enable_timer_wakeup(1 * 60L * 1000000L);
    esp_deep_sleep_start();
  }

  // If we get here, print the IP address on the LCD
  Serial.println(WiFi.localIP());
}

void reconnect() {
  // Loop until we're reconnected
  while (!client.connected()) {
    Serial.print("Attempting MQTT connection...");
    // Attempt to connect
    if (client.connect("LolinClient-EnergyMonitor", "oilkfgjy", "lEyZb90q49Rf")) {
      Serial.println("connected");
    } else {
      Serial.print("failed, rc=");
      Serial.print(client.state());
      Serial.println(" try again in 5 seconds");
      delay(5000);
    }
  }
}

void loop() {

  if (!client.connected()) {
    reconnect();
  }
  
  client.loop();
  
  unsigned long currentMillis = millis();

  // If it's been longer then 1000ms since we took a measurement, take one now!
  if (currentMillis - lastMeasurement > 1000) {
    double amps = emon1.calcIrms(1480); // Calculate Irms only
    double watt = amps * HOME_VOLTAGE;

    if(watt > 45) {
      Serial.print("watt optimized: ");
      Serial.println(watt*1.35);
    }

    // Update the display
    Serial.print("watt: ");
    Serial.println(watt);
    Serial.print("amps: ");
    Serial.println(amps);

    String toSend = "WO: " + String(watt*1.35) + ", W: " + String(watt) + ", A: " + String(amps);
    toSend.toCharArray(message_buff, toSend.length()+1);

    client.publish("Energy", message_buff);

    lastMeasurement = millis();

    // Readings are unstable the first 5 seconds when the device powers on
    // so ignore them until they stabilise.
    if (millis() - timeFinishedSetup < 10000) {
      Serial.println("Startup mode   ");
    } else {
      Serial.println(WiFi.localIP());
      measurements[measureIndex] = watt;
      measureIndex++;
    }
  }

  // When we have 30 measurements, send them to AWS!
  if (measureIndex == 30) {
    Serial.println("we have 30 measurements   ");

    // Construct the JSON to send to AWS
    String msg = "{\"readings\": [";

    for (short i = 0; i <= 28; i++) {
      msg += measurements[i];
      msg += ",";
    }

    msg += measurements[29];
    msg += "]}";

    Serial.println("Message is ready : " + msg);
    measureIndex = 0;
  }
}