//////////////////////////////////////////////////////////////////////
//REMINDER * change DHT TYPE TO DHT11
//           set relay inverted to HIGH
//////////////////////////////////////////////////////////////////////

#include <DHT.h>
#include <LiquidCrystal_I2C.h>
#include <EEPROM.h>

#define DHTPIN 14
#define DHTTYPE DHT22
DHT dht(DHTPIN, DHTTYPE);
LiquidCrystal_I2C lcd(0x27, 16,2);

byte Humidity_down_pin = 34;
byte timer_pin = 35;                          //pin for the timer dry button
byte on_off_button = 15;
byte Heaterandfanpin = 12;
byte buzzerPin = 23;
int defaulthumiditytarget = 50;
int min_humidity_target = 10;
unsigned long dry_timer = 30;                  //minutes
int alarm_temp = 50;
bool state_changed = HIGH;                     // set HIGH to start in OFF state, low to start in dehumidify state

//saved in eeprom
int max_temp = 45;
unsigned long backlight_timeout = 1;           //timout in minutes
bool Default_to_prev_humidity = LOW;           // HIGH - revert to previous humidity, LOW - revert to off
bool relay_is_inverterd = HIGH;                // set to high if relay changing is inverted
unsigned long Main_timeout = 4;                //timout in hours

//////////////////////////////////////////////////////////////////////
//dont edit below//dont edit below//dont edit below//dont edit below//
//////////////////////////////////////////////////////////////////////

byte mode = 0;
int savedtemp = 0;
int savedhum = 0;
bool on_off_state = LOW;
int newhumiditytarget = 50; //default humidity target
bool refresh = HIGH;
int before_timer_humidity = 30;
bool timer_already_tripped = HIGH;
int temperature;
int humidity;
bool on_off_pressed_once = LOW;

bool backlight_state = HIGH;
bool high_temp_state = LOW;
unsigned long dehumidify_time1 ;               //counter to check
unsigned long dehumidify_time2 ;               //counter to check
unsigned long saved_dehumidify_time2 ;

bool already_in_mode_0;
bool already_in_mode_1;
bool already_in_mode_2;
bool already_in_mode_3;

bool Humidity_down_pin_state = LOW;

unsigned long time1 ;            //couter to check
unsigned long time2 ;            //counter to check
unsigned long time3 ;            //time1 - time2
unsigned long time4 = 250;       //click check maximum for click, minimum for long click

unsigned long any_button_timer ;            //couter to check

void setup() {
  Serial.begin(9600);
  dht.begin();
  lcd.init();
  lcd.backlight();
  pinMode(on_off_button, INPUT);
  pinMode(Humidity_down_pin, INPUT);
  pinMode(timer_pin, INPUT);
  pinMode(Heaterandfanpin, OUTPUT);
  pinMode(buzzerPin, OUTPUT);
  digitalWrite(Heaterandfanpin, relay_is_inverterd);

  EEPROM.get(0, max_temp);
  EEPROM.get(10, backlight_timeout);
  EEPROM.get(20, Main_timeout);
  EEPROM.get(30, Default_to_prev_humidity);
  EEPROM.get(40, relay_is_inverterd);
}

void loop() { 

  temperature = dht.readTemperature();
  humidity = dht.readHumidity();

  //Read on off button for click
  if(digitalRead(on_off_button) == LOW && on_off_pressed_once == LOW){
    on_off_pressed_once = HIGH;
    lcd.backlight();
    any_button_timer = millis();
    time1 = millis();
    state_changed = LOW;
    delay(50);
  }
  if(digitalRead(on_off_button) == HIGH && on_off_pressed_once == HIGH){
  on_off_pressed_once = LOW;
  time2 = millis();
  delay(50);
  }

  time3 = time2 - time1; // DEFINITION OF time3 - DONT CHANGE THIS - for click and long click

  if(time3 < time4 && state_changed == LOW){
    state_changed = HIGH;
    if(mode >= 4){
      mode = mode + 1;
      refresh = HIGH;
    }
  }

  if(millis() - any_button_timer >= Main_timeout*60000*60){
    mode = 0;
  }

  //Backlight timeout
  if(millis() - any_button_timer >= backlight_timeout*60000){
    lcd.noBacklight();
  }

  //menu
  if(digitalRead(on_off_button) == LOW && (mode == 1 || mode == 2 || mode == 3)){
    mode = 0;
    refresh = HIGH;
  }

  //menu - MAX TEMP 
  if(time3 > time4 && state_changed == LOW && on_off_pressed_once == LOW){
    state_changed = HIGH;
    refresh = HIGH;
    if(mode >= 0 && mode <=3){
      mode = 4;
    } 
    else if( mode >=4){
      mode = 0;
    }
  }  

  //menu - MAX TEMP - change
  if (mode == 4){
    if(digitalRead(Humidity_down_pin) == LOW){
      max_temp = max_temp + 1;
      refresh = HIGH;
      delay(500);
    }
    if(digitalRead(timer_pin) == LOW){
      max_temp = max_temp - 1;
      refresh = HIGH;
      delay(500);
    }
  }

  if(mode == 5){

    if(backlight_timeout >= 0 && backlight_timeout < 10){
      if(digitalRead(Humidity_down_pin) == LOW){
        backlight_timeout = backlight_timeout + 1;
        refresh = HIGH;
        delay(500);
      }
      if(digitalRead(timer_pin) == LOW){
        backlight_timeout = backlight_timeout - 1;
        refresh = HIGH;
        delay(500);
      }      
    }

    else if(backlight_timeout >= 10){
      if(digitalRead(Humidity_down_pin) == LOW){
        backlight_timeout = backlight_timeout + 10;
        refresh = HIGH;
        delay(500);
      }
      if(digitalRead(timer_pin) == LOW){
        backlight_timeout = backlight_timeout - 10;
        refresh = HIGH;
        delay(500);
      }
    }
  }

  if(mode == 6){
    if(digitalRead(Humidity_down_pin) == LOW){
      Main_timeout = Main_timeout + 1;
      refresh = HIGH;
      delay(500);
    }
    if(digitalRead(timer_pin) == LOW && Main_timeout > 1){
      Main_timeout = Main_timeout - 1;
      refresh = HIGH;
      delay(500);
    }
  }

  if(mode == 7){
    if(digitalRead(Humidity_down_pin) == LOW){
      Default_to_prev_humidity = LOW;
      refresh = HIGH;
      delay(500);
    }
    if(digitalRead(timer_pin) == LOW && Main_timeout > 1){
      Default_to_prev_humidity = HIGH;
      refresh = HIGH;
      delay(500);
    }
  }

    if(mode == 8){
    if(digitalRead(Humidity_down_pin) == LOW){
      relay_is_inverterd = LOW;
      refresh = HIGH;
      delay(500);
    }
    if(digitalRead(timer_pin) == LOW){
      relay_is_inverterd = HIGH;
      refresh = HIGH;
      delay(500);
    }
  }

  if(mode == 9){
    if(digitalRead(Humidity_down_pin) == LOW){
      EEPROM.put(0, max_temp);
      EEPROM.put(10, backlight_timeout);
      EEPROM.put(20, Main_timeout);
      EEPROM.put(30, Default_to_prev_humidity);
      EEPROM.put(40, relay_is_inverterd);
      lcd.setCursor(0,0);
      lcd.print("SAVED TO EEPROM!");
      delay(2000);
      mode = 0;
      refresh = HIGH;
    }
  }

  //Refresh dislay if TEMPERATURE value change
  if(savedtemp < temperature || savedtemp > temperature){  //refresh the display only if this value changes
    savedtemp = temperature;
    refresh = HIGH;
  }
  //Refresh dislay if HUMIDITY value change
  if(savedhum < humidity || savedhum > humidity){      //refresh the display only if this value changes
    savedhum = humidity;
    refresh = HIGH;
  }

  //HIGH TEMPSTATE
  if(temperature > max_temp && high_temp_state == LOW){
    digitalWrite(Heaterandfanpin, relay_is_inverterd);
    high_temp_state = HIGH;
    refresh = HIGH;
  }
  //LOW TEMPSTATE
  if (temperature <= max_temp && high_temp_state == HIGH){
    digitalWrite(Heaterandfanpin, !relay_is_inverterd);
    high_temp_state = LOW;
    refresh = HIGH;
  }

  //ALARM STATE
  if(temperature >= alarm_temp){
    tone(buzzerPin, 2300);
    on_off_state = LOW;
    delay(100);
  } else if(temperature < max_temp){
    noTone(buzzerPin);
  }

  //MODE 0 - OFF
  if(mode == 0 && already_in_mode_0 == LOW){
    already_in_mode_0 = HIGH;
    already_in_mode_1 = LOW;
    already_in_mode_2 = LOW;
    already_in_mode_3 = LOW;
    digitalWrite(Heaterandfanpin, relay_is_inverterd);
    newhumiditytarget = defaulthumiditytarget;
    timer_already_tripped = HIGH;
    lcd.backlight();
    refresh = HIGH;
  }
  //MODE 1 - STANDBY
  if(mode == 1 && already_in_mode_1 == LOW){
    already_in_mode_0 = LOW;
    already_in_mode_1 = HIGH;
    already_in_mode_2 = LOW;
    already_in_mode_3 = LOW;
    digitalWrite(Heaterandfanpin, relay_is_inverterd);                           //turn off the heater
    lcd.backlight();
    refresh = HIGH;
  } 

  //MODE 1 - AUTO ON INTO MODE 2
  if(temperature < max_temp && mode == 1 && humidity > newhumiditytarget){                                         //only if below max temp
    mode = 2;
  }

  //MODE 2 - DEHUMIDFYING

  //MODE 2 - DEHUMIDIFYING BUTTON
  if(digitalRead(Humidity_down_pin) == LOW && Humidity_down_pin_state == LOW && (mode == 0 || mode == 1 || mode == 2 || mode == 3)){
    Humidity_down_pin_state = HIGH;
    lcd.backlight();
    any_button_timer = millis();

    //REDUCE TARGET HUMIDITY
    if(newhumiditytarget > min_humidity_target){                      //if the humidity above min humidity 
      newhumiditytarget = newhumiditytarget - 5;                      //subtract 5%
      refresh = HIGH;
    }
    //GO BACK TO DEFAULT HUMIDITY
    else {
      newhumiditytarget = defaulthumiditytarget;                      //otherwise reset to default min
      refresh = HIGH;
      }
      mode = 2;
    }
    else if(digitalRead(Humidity_down_pin) == HIGH){
    Humidity_down_pin_state = LOW;
  }

  //MODE 2 - EXECUTE - TURN OFF
  if(mode == 2 && already_in_mode_2 == LOW){                  //set to mode 0 if "off"
    already_in_mode_0 = LOW;
    already_in_mode_1 = LOW;
    already_in_mode_2 = HIGH;
    already_in_mode_3 = LOW;
    digitalWrite(Heaterandfanpin, !relay_is_inverterd);              //turn off the heater
    timer_already_tripped = LOW;
    refresh = HIGH;
    delay(500);                                                     //delay prevents multiclicking
  }
  
  if(mode == 2 && humidity < newhumiditytarget){                          //only if below max temp
    mode = 1;
  }
    
  //MODE 3 - TIMER
  if(digitalRead(timer_pin) == LOW && (mode == 0 || mode == 1 || mode == 2 || mode == 3)){
    mode = 3;
    lcd.backlight();
    any_button_timer = millis();
    on_off_pressed_once = LOW;
    already_in_mode_0 = LOW;
    digitalWrite(Heaterandfanpin, !relay_is_inverterd);
    dehumidify_time1 = millis();
    timer_already_tripped = LOW;
    saved_dehumidify_time2 = 0;
    if(newhumiditytarget != 0){                               //save the non 0 value of prev humidity target
      before_timer_humidity = newhumiditytarget;
      newhumiditytarget = 0;
      refresh = HIGH;
    }
  }

  if(mode == 3){                                              //refresh the display only if this value changes
    dehumidify_time2 = millis() - dehumidify_time1;
    if(dehumidify_time2 >= saved_dehumidify_time2 + 1000){
      saved_dehumidify_time2 = dehumidify_time2;
    }
  }

  if(dehumidify_time2 >= dry_timer*60000 && timer_already_tripped == LOW && mode == 3){   //execute this once after timer elapsed
    timer_already_tripped = HIGH;
    newhumiditytarget = before_timer_humidity;                    // restore to prev humidity target
    refresh = HIGH;
    if(Default_to_prev_humidity == HIGH){
      mode = 2;
    } 
    else{
      mode = 0;
      on_off_state = LOW;
    }
  }

  //LCD
  if(refresh == HIGH){
    lcd.clear();
    refresh = LOW;

    if(mode == 0){
      lcd.setCursor(0,0);
      lcd.print("OFF");
      lcd.setCursor(0,1);
      lcd.print(temperature);
      lcd.print((char)223);
      lcd.print("C");
      if(temperature > max_temp){
        lcd.print("!");
      }
      lcd.setCursor(8,1);
      lcd.print(humidity);
      lcd.print("%");
    }

    if(mode == 1){
      lcd.setCursor(0,0);
      lcd.print("STANDBY");
      lcd.setCursor(0,1);
      lcd.print(temperature);
      lcd.print((char)223);
      lcd.print("C");
      if(temperature > max_temp){
        lcd.print("!");
      }
      lcd.setCursor(8,1);
      lcd.print(humidity);
      lcd.print("%");
      lcd.print((char)126);
      lcd.print(newhumiditytarget);
      lcd.print("%");
    }

    if(mode == 2){
      lcd.setCursor(0,0);
      lcd.print("DRYING FILAMENT");
      lcd.setCursor(0,1);
      lcd.print(temperature);
      lcd.print((char)223);
      lcd.print("C");
      if(temperature > max_temp){
        lcd.print("!");
      }
      lcd.setCursor(8,1);
      lcd.print(humidity);
      lcd.print("%");
      lcd.print((char)126);
      lcd.print(newhumiditytarget);
      lcd.print("%");
    }

    if(mode == 3){
      lcd.setCursor(0,0);
      lcd.print("TIMER");
      lcd.setCursor(8,0);
      lcd.print(dry_timer - dehumidify_time2/60000);
      lcd.print(" min");
      lcd.setCursor(0,1);
      lcd.print(temperature);
      lcd.print((char)223);
      lcd.print("C");
      if(temperature > max_temp){
        lcd.print("!");
      }
      lcd.setCursor(8,1);
      lcd.print(humidity);
      lcd.print("%");
      lcd.print((char)126);
      lcd.print(newhumiditytarget);
      lcd.print("%");
    }    

    if(mode == 4){
      lcd.setCursor(0,0);
      lcd.print((char)127);
      lcd.print("MAX TEMP");
      lcd.setCursor(15,0);
      lcd.print((char)126);
      lcd.setCursor(1,1);
      lcd.print(max_temp);
      lcd.print((char)223);            
    }      

    if(mode == 5){
      lcd.setCursor(0,0);
      lcd.print((char)127);
      lcd.print("LIGHT TIMEOUT");
      lcd.setCursor(15,0);
      lcd.print((char)126);
      lcd.setCursor(1,1);
      lcd.print(backlight_timeout);
      if(backlight_timeout == 1){
        lcd.print(" MINUTE");
      }
      else{
        lcd.print(" MINUTES");
      }
    } 

    if(mode == 6){
      lcd.setCursor(0,0);
      lcd.print((char)127);
      lcd.print("MAIN TIMEOUT");
      lcd.setCursor(15,0);
      lcd.print((char)126);
      lcd.setCursor(1,1);
      lcd.print(Main_timeout);
      if(Main_timeout == 1){
        lcd.print(" HOUR");
      }
      else{
        lcd.print(" HOURS");
      }
    } 

    if(mode == 7){
      lcd.setCursor(0,0);
      lcd.print((char)127);
      lcd.print("TIME END INTO");
      lcd.setCursor(15,0);
      lcd.print((char)126);
      lcd.setCursor(1,1);
      if(Default_to_prev_humidity == HIGH){
        lcd.print("DEHUMIDIFY");
      }
      else{
        lcd.print("OFF MODE");
      } 
    }

    if(mode == 8){
      lcd.setCursor(0,0);
      lcd.print((char)127);
      lcd.print("RELAY MODE");
      lcd.setCursor(15,0);
      lcd.print((char)126);
      lcd.setCursor(1,1);
      if(relay_is_inverterd == HIGH){
        lcd.print("INVERTED");
      }
      else{
        lcd.print("NORMAL");
      } 
    }

    if(mode == 9){
      lcd.setCursor(0,0);
      lcd.print((char)127);
      lcd.print("SAVE TO EEPROM"); 
    }
  }
}