#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>
#include <DS1307RTC.h>

#define SCREEN_WIDTH 128
#define SCREEN_HEIGHT 64
#define OLED_RESET -1
#define BUZZER_PIN 2
#define BUTTON_PIN_SET 3
#define BUTTON_PIN_HOUR 4
#define BUTTON_PIN_MIN 5
#define BUTTON_PIN_STOP 6

Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);

int alarmHour = 6;
int alarmMinute = 00;
int alarmSecond = 00;
String alarmAMPM = "AM";
bool buzzerActive = false;
bool alarmEnabled = true;

bool alarmSetMode = false;
bool hourEditMode = false;
bool minuteEditMode = false;

int lastState = LOW;  // the previous state from the input pin
int currentState;     // the current reading from the input pin
unsigned long pressedTime  = 0;
unsigned long releasedTime = 0;

tmElements_t tm;
int hour12 = (tm.Hour % 12 == 0) ? 12 : tm.Hour % 12;
String ampm = (tm.Hour < 12) ? "AM" : "PM";

void setup() {

  Serial.begin(115200);
  if (!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) {
    Serial.println(F("SSD1306 allocation failed"));
    for (;;);
  }

  pinMode(BUZZER_PIN, OUTPUT);
  pinMode(BUTTON_PIN_SET, INPUT_PULLUP);
  pinMode(BUTTON_PIN_HOUR, INPUT_PULLUP);
  pinMode(BUTTON_PIN_MIN, INPUT_PULLUP);
  pinMode(BUTTON_PIN_STOP, INPUT_PULLUP);

  delay(100);
  display.clearDisplay();
  display.setTextColor(WHITE);
}

void printDateTime(tmElements_t tm, bool showAMPM = true) {

  int hour12 = (tm.Hour % 12 == 0) ? 12 : tm.Hour % 12;
  String ampm = (tm.Hour < 12) ? "AM" : "PM";

  // MM/DD/YY
  display.print(tm.Month);
  display.print("/");
  display.print(tm.Day);
  display.print("/");
  display.print((tmYearToCalendar(tm.Year)) % 100);
  display.print("      ");

  // HH:MM
  display.print(hour12);
  if (tm.Second % 2 == 0) {
    display.print(":");
  } else {
    display.print(" ");
  }  
  if (tm.Minute < 10) display.print("0");
  display.print(tm.Minute);
  if (showAMPM) {
    display.print(" ");
    display.println(ampm);
  }
}

void printAlarmTime() {
  display.print(" Alarm Time: ");
  display.print(alarmHour);
  display.print(":");
  if (alarmMinute < 10) display.print("0");
  display.print(alarmMinute);
  display.print(" ");
  display.println(alarmAMPM);
}

void printSetAlarmTime() {
  
  display.print(" Set Alarm: ");
  display.setTextColor(BLACK, WHITE);

  static bool ampmChangeDone = false;
  if (hourEditMode) {
    if (alarmHour == 12 && !ampmChangeDone) {
      if (alarmAMPM == "AM") {
        alarmAMPM = "PM";
      } else {
        alarmAMPM = "AM";
      }
      ampmChangeDone = true;
    } 
    else if (alarmHour != 12) {
      ampmChangeDone = false;
    }

    if (alarmHour < 10) {
      display.print(" ");
    }
    display.print(alarmHour);
    display.print(":");
  } else {
    if (alarmHour < 10) {
      display.print(" ");
    }
    display.print(alarmHour);
    display.print(":");
  }
  
  if (alarmMinute < 10) display.print("0");
  display.print(alarmMinute);
  display.print(" ");
  display.println(alarmAMPM);
}

void loop() {
  // Read current time
  tmElements_t tm;
  RTC.read(tm);

  // Initialize screen
  display.clearDisplay();
  display.setTextSize(1);
  display.setTextColor(SSD1306_WHITE);

  // Display current date/time
  display.setCursor(0, 0);
  int hour12 = (tm.Hour % 12 == 0) ? 12 : tm.Hour % 12;
  String ampm = (tm.Hour < 12) ? "AM" : "PM";
  printDateTime(tm);


  if (!alarmEnabled) {
    display.setCursor(0, 15);
    display.print("      Alarm OFF");
    display.setCursor(0, 27);
    display.print("   SLEEP IN, BOZO");

  } else {
    display.setCursor(0, 15);
    display.print("      Alarm ON");
    display.setCursor(0, 27);
    display.print("    GET UP, BOZO");
  }

  // Setting the alarm
  if (alarmSetMode) {
    // Hour adjust
    if (digitalRead(BUTTON_PIN_HOUR) == LOW) {
      hourEditMode = !hourEditMode;
      if (hourEditMode) {
        alarmHour = (alarmHour + 1) % 13;
        if (alarmHour == 0) alarmHour = 1;
        delay(50);
      }
    }
    // Minute adjust
    if (digitalRead(BUTTON_PIN_MIN) == LOW) {
      minuteEditMode = !minuteEditMode;
      if (minuteEditMode) {
        alarmMinute = (alarmMinute + 1) % 60;
        delay(50);
      }
    }
  }

  // Display alarm time
  display.setCursor(0, 50);
  if (alarmSetMode) {
    printSetAlarmTime();
  } else {
    printAlarmTime();
  }

  // Toggle between Alarm on/off
  int currentState = digitalRead(BUTTON_PIN_SET);

  if (lastState == HIGH && currentState == LOW) {     // button is pressed
    pressedTime = millis();
  }  
  else if (lastState == LOW && currentState == HIGH) { // button is released
    releasedTime = millis(); 
    long pressDuration = releasedTime - pressedTime;
    if (pressDuration < 1000) // Short press = alarm set mode
      alarmSetMode = !alarmSetMode;  
    if(pressDuration > 1000) // Long press = enable/disable alarm
      alarmEnabled = !alarmEnabled;
  }
  // Save the last state
  lastState = currentState;

  // Alarm Conditions
  //if (hour12 == alarmHour && tm.Minute == alarmMinute && tm.Second == alarmSecond && ampm == alarmAMPM && alarmEnabled == true) {
  if (hour12 == alarmHour && tm.Minute == alarmMinute && tm.Second == alarmSecond && ampm == alarmAMPM && alarmEnabled == true && alarmSetMode == false) {

    if (!buzzerActive) {
      tone(BUZZER_PIN, 1000);
      buzzerActive = true;
    }
  }

  // Check if the button is pressed to stop the alarm
  if (digitalRead(BUTTON_PIN_STOP) == LOW && alarmEnabled == true) {
    noTone(BUZZER_PIN);
    buzzerActive = false;
    delay(50);  // Debounce delay
    pinMode(BUTTON_PIN_STOP, INPUT_PULLUP);
  }

  display.display();
  delay(50);
}


//    1/16/24
// added white text for alarm set time. had to rearrange code in void loop() and add stuff to printAlarmSetTime