#include <Wire.h>
#include <LiquidCrystal_I2C.h>
#include <RTClib.h>
#include <FreeRTOS.h>
#include <task.h>

#define I2C_ADDR    0x27
#define LCD_COLUMNS 16
#define LCD_LINES   2
#define WHITE_PIN 11
#define YELLOW_PIN 10
#define PHOTO_PIN A3
#define POT_PIN A1
#define MODE_PIN 8
#define SHUTDOWN_PIN 7

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

int brightness = 0;
bool manual_mode = false;
String mode = "";

LiquidCrystal_I2C lcd(I2C_ADDR, LCD_COLUMNS, LCD_LINES);
RTC_DS1307 rtc;

void setup() {
  lcd.init();
  lcd.backlight();
  Serial.begin(9600);

  pinMode(MODE_PIN, INPUT_PULLUP);
  pinMode(SHUTDOWN_PIN, INPUT_PULLUP);
  pinMode(PHOTO_PIN, INPUT);
  pinMode(POT_PIN, INPUT);
  pinMode(WHITE_PIN, OUTPUT);
  pinMode(YELLOW_PIN, OUTPUT);

  rtc.begin();
}

float readLux(){
  int analogValue = analogRead(PHOTO_PIN);
  float voltage = analogValue / 1024. * 5;
  float resistance = 2000 * voltage / (1 - voltage / 5);
  float lux = pow(RL10 * 1e3 * pow(10, GAMMA) / resistance, (1 / GAMMA));
  return lux;
}

void printScr(DateTime now, String mode, int brightness, int luxValue){
  // Вывод информации на экран
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print(now.hour(), DEC);
  lcd.print(":");
  lcd.print(now.minute(), DEC);
  lcd.print(":");
  lcd.print(now.second(), DEC);
  lcd.setCursor(10, 0);
  lcd.print(mode);
  lcd.setCursor(0, 1);
  lcd.print("LED:");
  lcd.print(brightness);
  lcd.print(" Lux:");
  lcd.print(luxValue);
}

int mainTask(DateTime now, int luxValue, int potentiometerValue){
    if(!digitalRead(SHUTDOWN_PIN)){
    digitalWrite(YELLOW_PIN, LOW);
    analogWrite(WHITE_PIN, 0);
  }
  else{

  manual_mode = digitalRead(MODE_PIN);
  bool yellowOn = now.hour() >= 19 || now.hour() < 12;

  if(manual_mode){
    mode = "Manual";
  }
  else {
    mode = "Auto";
  }

  if (!manual_mode) {
    if (yellowOn) {
      if (luxValue >= 0 && luxValue < 100) {
        brightness = 255;
      } else if (luxValue >= 100 && luxValue < 200) {
        brightness = 127;
      } else if (luxValue >= 200 && luxValue < 300) {
        brightness = 63;
      } else if (luxValue >= 300){
        brightness = 0;
      }
    }
  } 
  else {
    brightness = map(potentiometerValue, 0, 1023, 0, 255);
  }

  analogWrite(WHITE_PIN, brightness);
  digitalWrite(YELLOW_PIN, yellowOn ? HIGH : LOW);
  }
  return brightness;
}

void loopTask(void *pvParameters) {
  while(1) {
    DateTime now = rtc.now();
    int luxValue = readLux();
    int potentiometerValue = analogRead(POT_PIN);
    int switchState = digitalRead(MODE_PIN);

    printScr(now, mode, mainTask(now, luxValue, potentiometerValue), luxValue);
    // Serial.println(luxValue);
    // Serial.println(brightness);
    vTaskDelay(1000 / portTICK_PERIOD_MS);
  }
}

void setupFreeRTOS() {
  xTaskCreate(
    loopTask,          // Функция задачи
    "Main Loop Task",  // Имя задачи
    256,               // Размер стека
    NULL,              // Входной параметр
    1,                 // Приоритет
    NULL               // Обработчик задачи
  );
}

void loop() {
  setupFreeRTOS();
  vTaskStartScheduler();
}