//Including all needed libraries for this MEDIBOX project
#include <Adafruit_GFX.h>        
#include <Adafruit_SSD1306.h>
#include <Wire.h>
#include <DHTesp.h>              // for DHT22 sensor
#include <WiFi.h>                // for time from wifi

//Defining OLED Display parameters
#define Screenwidth 128
#define Screenheight 64
#define OLEDReset -1
#define ScreenAddress 0x3C

//Defining the corresponding pins in ESP32 for the elements
#define BUZZER 5
#define LED_1  15
#define PB_CANCEL 34
#define PB_OK 32
#define PB_UP 33
#define PB_DOWN 35
#define DHTPIN 12

//Defining the time from wifi 
#define NTP_SERVER     "pool.ntp.org"
#define UTC_OFFSET     19800
#define UTC_OFFSET_DST 0

long utc_offset_sec = 0;

Adafruit_SSD1306 display(Screenwidth, Screenheight, &Wire, OLEDReset);
DHTesp dhtSensor;

//Declaration of all Global Variables
int days = 0;
int hours = 0;
int minutes = 0;
int seconds = 0;

boolean alarm_enabled = true;
int n_alarms = 3;
int alarm_hours[] = {0,0,0};
int alarm_minutes[] = {0,0,0};
bool alarm_triggered[] = {false, false, false};

int n_notes = 8;
int C = 262;
int D = 294;
int E = 330;
int F = 349;
int G = 392;
int A = 440;
int B = 494;
int C_H = 523;
int notes[] = {C, D, E, F, G, A, B, C_H};

unsigned long timeNow = 0;
unsigned long timeLast = 0;

int current_mode = 0;
int max_modes = 5;
String modes[] = {"1 - Set Time", "2 - Set Alarm 1", "3 - Set Alarm 2", "4 - Set Alarm 3", "5 - Disable Alarms"};

void setup() {
  pinMode(BUZZER, OUTPUT);
  pinMode(LED_1, OUTPUT);
  pinMode(PB_CANCEL, INPUT);
  pinMode(PB_DOWN, INPUT);
  pinMode(PB_OK, INPUT);
  pinMode(PB_UP, INPUT);

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

  Serial.begin(9600);
  if(!display.begin(SSD1306_SWITCHCAPVCC, ScreenAddress)) {
    Serial.println(F("SSD1306 Allocation Failed"));
    for(;;);
  }

  display.display();
  delay(500);

  WiFi.begin("Wokwi-GUEST", "", 6);
  while (WiFi.status() != WL_CONNECTED) {
    delay(250);
    display.clearDisplay();
    print_line("Connecting to WIFI....", 2, 0, 2);
  }

  display.clearDisplay();
  print_line("Connected to WIFI.", 2, 0, 2);

  configTime(UTC_OFFSET, UTC_OFFSET_DST, NTP_SERVER);

  display.clearDisplay();

  print_line("Welcome to Medi Box", 2, 0, 0);
  display.clearDisplay();

  
}

void loop(){
  update_time_with_check_alarm();
  if (digitalRead(PB_OK) == LOW){
    delay(200);
    go_to_menu();
  }

  check_temp();

}

void print_line(String text, int text_size, int row, int column){


  display.setTextSize(text_size);
  display.setTextColor(SSD1306_WHITE);
  display.setCursor(column,row);
  display.println(text);

  display.display();
}

void set_timezone() {
  int current_offset_hours = utc_offset_sec / 3600;
  int current_offset_minutes = (utc_offset_sec % 3600) / 60;

  int offset_hours = read_value("Enter offset hours: ", current_offset_hours, 14, -12);
  int offset_minutes = read_value("Enter offset minutes: ", current_offset_minutes, 59, 0);

  utc_offset_sec = offset_hours * 3600 + offset_minutes * 60;
  configTime(utc_offset_sec, UTC_OFFSET_DST, NTP_SERVER);
  print_line("Timezone set to " + String(offset_hours) + ":" + String(offset_minutes), 0, 0, 2);
  delay(250);
}
// function to display the current time DD:HH:MM:SS 
void print_time_now(void) { 
  display.clearDisplay();

  print_line(String(hours), 2, 0, 30); 
  print_line(":" , 2, 0, 50); 
  print_line(String(minutes), 2, 0, 60);
  print_line(":" , 2, 0, 80); 
  print_line(String(seconds), 2, 0, 90); 
}

void update_time(void) {
 struct tm timeinfo;
 getLocalTime(&timeinfo);

 char timeHour[3];
 strftime(timeHour,3, "%H", &timeinfo);
 hours = atoi(timeHour);

 char timeMinute[3];
 strftime(timeMinute,3, "%M", &timeinfo);
 minutes = atoi(timeMinute);

 char timeSecond[9];
 strftime(timeSecond,9, "%S", &timeinfo);
 seconds = atoi(timeSecond);
}

void ring_alarm(){
  display.clearDisplay();
  print_line("MEDICINE TIME", 0, 0, 2);

  digitalWrite(LED_1, HIGH);

  bool break_happened = false;

  while(break_happened == false && digitalRead(PB_CANCEL) == HIGH){
    for (int i=0; i<n_notes; i++){
      if (digitalRead(PB_CANCEL) == LOW){
        delay(200);
        break_happened == true;
        break;
      }
      tone(BUZZER, notes[i]);
      delay(500);
      noTone(BUZZER);
      delay(2);
    }
  }
  digitalWrite(LED_1, LOW);
  display.clearDisplay();
}

// function to automatically update the current time while checking for alarms 
void update_time_with_check_alarm(void){
  update_time();
  print_time_now();

  if (alarm_enabled == true){
    for (int i = 0; i < n_alarms; i++){
      if (alarm_triggered[i]==false && alarm_hours[i] == hours && alarm_minutes[i] == minutes){
        ring_alarm();
        alarm_triggered[i] = true;
      } 
    }
  }
}

int wait_for_button_press(){
  while(true){
    if (digitalRead(PB_UP)==LOW){
      delay(200);
      return PB_UP;
    }

    else if (digitalRead(PB_DOWN)==LOW){
      delay(200);
      return PB_DOWN;
    }

    else if (digitalRead(PB_CANCEL)==LOW){
      delay(200);
      return PB_CANCEL;
    }

    else if (digitalRead(PB_OK)==LOW){
      delay(200);
      return PB_OK;
    }

    update_time();
  }
}

void go_to_menu(void){
  while (digitalRead(PB_CANCEL) == HIGH){
    display.clearDisplay();
    print_line(modes[current_mode], 0, 0, 2);

    int pressed = wait_for_button_press();
    if (pressed == PB_UP){
      delay(200);
      current_mode += 1;
      current_mode = current_mode % max_modes;
    }

    else if (pressed == PB_DOWN){
      delay(200);
      current_mode -= 1;
      if(current_mode < 0){
        current_mode = max_modes - 1;
      }
    }

    else if (pressed == PB_OK){
      delay(200);
      run_mode(current_mode);
    }

    if (pressed == PB_CANCEL){
      delay(200);
      break;
    }


  }

}

void set_time(){
  int temp_hour = hours;
  
  while(true){
    display.clearDisplay();
    print_line("Enter hour: " + String(temp_hour), 0, 0, 2);
  
  int pressed = wait_for_button_press();
    if (pressed == PB_UP){
      delay(200);
      temp_hour += 1;
      temp_hour = temp_hour % 24;
    }

    else if (pressed == PB_DOWN){
      delay(200);
      temp_hour -= 1;
      if(temp_hour < 0){
        temp_hour = 23;
      }
    }

    else if (pressed == PB_OK){
      delay(200);
      hours = temp_hour;
      break;
    }

    if (pressed == PB_CANCEL){
      delay(200);
      break;
    }
  }

  int temp_minute = minutes;
  
  while(true){
    display.clearDisplay();
    print_line("Enter minutes: " + String(temp_minute), 0, 0, 2);
  
  int pressed = wait_for_button_press();
    if (pressed == PB_UP){
      delay(200);
      temp_minute += 1;
      temp_minute = temp_minute % 60;
    }

    else if (pressed == PB_DOWN){
      delay(200);
      temp_minute -= 1;
      if(temp_minute < 0){
        temp_minute = 59;
      }
    }

    else if (pressed == PB_OK){
      delay(200);
      minutes = temp_minute;
      break;
    }

    if (pressed == PB_CANCEL){
      delay(200);
      break;
    }
  }

display.clearDisplay();
print_line("Time is SET", 0, 0, 2);
delay(1000);
  
}

void set_alarm(int alarm){
  int temp_hour = alarm_hours[alarm];
  
  while(true){
    display.clearDisplay();
    print_line("Enter hour: " + String(temp_hour), 0, 0, 2);
  
  int pressed = wait_for_button_press();
    if (pressed == PB_UP){
      delay(200);
      temp_hour += 1;
      temp_hour = temp_hour % 24;
    }

    else if (pressed == PB_DOWN){
      delay(200);
      temp_hour -= 1;
      if(temp_hour < 0){
        temp_hour = 23;
      }
    }

    else if (pressed == PB_OK){
      delay(200);
      alarm_hours[alarm] = temp_hour;
      break;
    }

    if (pressed == PB_CANCEL){
      delay(200);
      break;
    }
  }

  int temp_minute = alarm_minutes[alarm];
  
  while(true){
    display.clearDisplay();
    print_line("Enter minute: " + String(temp_minute), 0, 0, 2);
  
  int pressed = wait_for_button_press();
    if (pressed == PB_UP){
      delay(200);
      temp_minute += 1;
      temp_minute = temp_minute % 60;
    }

    else if (pressed == PB_DOWN){
      delay(200);
      temp_minute -= 1;
      if(temp_minute < 0){
        temp_minute = 59;
      }
    }

    else if (pressed == PB_OK){
      delay(200);
      alarm_minutes[alarm] = temp_minute;
      break;
    }

    if (pressed == PB_CANCEL){
      delay(200);
      break;
    }
  }



display.clearDisplay();
print_line("Alarm is SET", 0, 0, 2);
delay(1000);

}

void run_mode(int mode){
  if(mode == 0){
    set_time();
  }

  else if(mode == 1 || mode == 2 || mode == 3){
    set_alarm(mode - 1);
  }

  else if (mode == 4) {
    disable_the_alarms();
  }
}

void check_temp(){
  TempAndHumidity data = dhtSensor.getTempAndHumidity() ; 
  if (data.temperature > 32){
    display.clearDisplay();
    print_line("TEMP HIGH", 0, 40, 1);
  }

  if (data.temperature < 26){
    display.clearDisplay();
    print_line("TEMP LOW", 0, 40, 1);
  }

  if (data.humidity > 80){
    display.clearDisplay();
    print_line("HUMIDITY HIGH", 0, 50, 1);
  }

  if (data.humidity < 60){
    display.clearDisplay();
    print_line("HUMIDITY LOW", 0, 50, 1);
  }

}

int read_value(String text, int init_value, int max_value, int min_value) {
  int temp_value = init_value;
  while (true) {
    print_line(text + String(temp_value), 0, 0, 2);

    int pressed = wait_for_button_press();

    if (pressed == PB_UP) {
      delay(200);
      temp_value += 1;
      if (temp_value > max_value) {
        temp_value = min_value;
      }
    }

    else if (pressed == PB_DOWN) {
      delay(200);
      temp_value -= 1;
      if (temp_value < min_value) {
        temp_value = max_value;
      }
    }

    else if (pressed == PB_OK) {
      delay(200);
      return temp_value;
    }

    else if (pressed == PB_CANCEL) {
      delay(200);
      break;
    }
  }

  return init_value;
}

void disable_the_alarms() {
  alarm_enabled = false;
  // Clear all the alarms
  for (int i = 0; i < n_alarms; i++) {
    int alarm_hours[] = {0,0,0};
    int alarm_minutes[] = {0,0,0};
  }
  display.clearDisplay();
  print_line("Alarms are disabled", 0, 0, 2);
  delay(1000);
}