// Station 1 Microcontroller Script

// Initialize libraries
#include <Wire.h>
#include <Adafruit_ADS1015.h>
#include "hw_timer.h"
#include <Filters.h>                      //This library does a massive work check it's .cpp file
#include "FirebaseESP8266.h"
#include <ESP8266WiFi.h>
#include <LiquidCrystal_I2C.h>

// Define all objects and constant variables
Adafruit_ADS1115 ads1015;
FirebaseData firebaseData;
LiquidCrystal_I2C lcd(0x27, 16, 2);
RunningStatistics inputStats_voltage;
RunningStatistics inputStats_current;
#define ACS_Pin A0
#define FIREBASE_HOST "myiotcloud-258019.firebaseio.com"
#define FIREBASE_AUTH "XHCMDEOzgC3Xd9FgEHvidY7nSusDLAWPz855XZW5"
const char WIFI_SSID[]        = "WIFI_SSID";
const char WIFI_PASSWORD[]    = "WIFI_PASSWORD";
const int sensorIn = A0;
const byte zcPin = 12;
const byte pwmPin = 13;
const int relay = 2;

// Initialize all variables
int mVperAmp = 185; //Sensitivity of 5A current module
double Voltage = 0;
double VRMS = 0;
double AmpsRMS = 0;
byte fade = 1;
byte state = 1;
byte tarBrightness = 255;
byte curBrightness = 0;
byte zcState = 0; // 0 = ready; 1 = processing;
float ACS_Value_Voltage;
float ACS_Value_Current;
float testFrequency = 60; // Set based on using 120V 60Hz AC source
float windowLength = 1000.0/testFrequency; // Provides period of 16.7 ms
float intercept_voltage = -0.04; // adjusted based on calibration testing
float slope_voltage = 0.004; // adjusted based on calibration testing
float intercept_current = 0;
float slope_current = 0.0016;
float Volts_TRMS;
float Amps_TRMS;
unsigned long printPeriod = 500;
unsigned long previousMillis = 0;

void setup(){
  Serial.begin(115200);

  //Define pin modes
  pinMode(zcPin, INPUT_PULLUP);
  pinMode(pwmPin, OUTPUT);
  pinMode(ACS_Pin,INPUT);
  attachInterrupt(zcPin, zcDetectISR, RISING);    // Attach an Interupt to Pin 2 (interupt 0) for Zero Cross Detection
  pinMode(relay, OUTPUT);

  // Initialize AC dimmer, LCD, ADS1115, ACS712, ZMPT101B
  hw_timer_init(NMI_SOURCE, 0);
  hw_timer_set_func(dimTimerISR);
  ads1015.begin();
  inputStats_voltage.setWindowSecs( windowLength );     //Set the window length
  inputStats_current.setWindowSecs( windowLength );
  lcd.init();
  lcd.backlight();

  // Connect to WiFi and Firebase
  WiFi.begin(WIFI_SSID, WIFI_PASSWORD);
  Serial.print("Connecting to Wi-Fi");
  while (WiFi.status() != WL_CONNECTED)
  {
    Serial.print(".");
    delay(300);
  }
  Serial.println();
  Serial.print("Connected with IP: ");
  Serial.println(WiFi.localIP());
  Serial.println();
  Firebase.begin(FIREBASE_HOST, FIREBASE_AUTH); //, WIFI_SSID, WIFI_PASSWORD);
  Firebase.reconnectWiFi(true);
}

void loop(){
    // Check if relay has been switched to ON
    if (Firebase.getString(firebaseData, "/ChargingStation1/station1Relay")){
      if (firebaseData.stringData() == "ON"){

        // Set relay ON and set AC dimmer value according to Firebase
        digitalWrite(relay, LOW);
        Firebase.getInt(firebaseData, "/ChargingStation1/AC_dimmer_value");
        int num = firebaseData.intData();
        tarBrightness = num;

        // Get time and loop while the time is not finished
        Firebase.getFloat(firebaseData, "/ChargingStation1/time");
        float time = firebaseData.floatData() * 1000;
        currentMillis = millis();
        Serial.print("Time: "); Serial.println(time);
        while(millis() - currentMillis <= time){

          // Read raw current and voltage values and convert to True RMS values
          ACS_Value_Voltage = analogRead(A0);
          ACS_Value_Current = ads1015.readADC_SingleEnded(1);
          inputStats_voltage.input(ACS_Value_Voltage);  // log to Stats function
          inputStats_current.input(ACS_Value_Current);
          Volts_TRMS = intercept_voltage + slope_voltage * inputStats_voltage.sigma();
          Volts_TRMS = Volts_TRMS * 161;
          Amps_TRMS = intercept_current + slope_current * inputStats_current.sigma();
          float Watts_TRMS = Amps_TRMS * Volts_TRMS;

          // Upload current, voltage and power values to Firebase and display on LCD
          Serial.print("Current: "); Serial.println(Amps_TRMS);
          Serial.print("Voltage: "); Serial.println(Volts_TRMS);
          Serial.print("Power: "); Serial.println(Watts_TRMS);

          if (Firebase.setFloat(firebaseData, "/ChargingStation1/CurrentValue", Amps_TRMS)){
          } else {
            Serial.println(firebaseData.errorReason());
          }

          if (Firebase.setFloat(firebaseData, "/ChargingStation1/VoltageValue", Volts_TRMS)){
          } else {
            Serial.println(firebaseData.errorReason());
          }

          if (Firebase.setFloat(firebaseData, "/ChargingStation1/PowerValue", Watts_TRMS)){
          } else {
            Serial.println(firebaseData.errorReason());
          }

          lcd.clear();
          lcd.setCursor(1,0);
          lcd.print("Station 1");
          lcd.setCursor(1,1);
          lcd.print(String(round(Volts_TRMS*100)/100) + " V " + String((Amps_TRMS*100/100)) + " A");
        }

        // After charging is complete, reset values on Firebase and wait for next user command
        Firebase.setString(firebaseData, "/ChargingStation1/ChargingRate", "0");
        Firebase.setString(firebaseData, "/ChargingStation1/station1Relay", "Off");
        Firebase.setInt(firebaseData, "/ChargingStation1/CanBeSupplied", 0);
        Serial.print("TIME IS FINISHED");
      } else {
        digitalWrite(relay, HIGH);
      }
    }
    delay(250);
}

void dimTimerISR() {
    if (fade == 1) {
      if (curBrightness > tarBrightness || (state == 0 && curBrightness > 0)) {
        --curBrightness;
      }
      else if (curBrightness < tarBrightness && state == 1 && curBrightness < 255) {
        ++curBrightness;
      }
    }
    else {
      if (state == 1) {
        curBrightness = tarBrightness;
      }
      else {
        curBrightness = 0;
      }
    }

    if (curBrightness == 0) {
      state = 0;
      digitalWrite(pwmPin, 0);
    }
    else if (curBrightness == 255) {
      state = 1;
      digitalWrite(pwmPin, 1);
    }
    else {
      digitalWrite(pwmPin, 1);
    }

    zcState = 0;
}

void zcDetectISR() {
  if (zcState == 0) {
    zcState = 1;


    if (curBrightness < 255 && curBrightness > 0) {
      digitalWrite(pwmPin, 0);
      int dimDelay = 30 * (255 - curBrightness) + 400;//400
      hw_timer_arm(dimDelay);
    }
  }
}