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

#define SCREEN_WIDTH 128 // OLED display width
#define SCREEN_HEIGHT 64 // OLED display height
#define OLED_RESET     -1 // No reset pin

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

RTC_DS3231 rtc;
const int pwmPin1 = 19;
const int ledcChannel1 = 0;
const int pwmPin2 = 18; // New PWM pin
const int ledcChannel2 = 1; // New LEDC channel
const int freq = 5000;
const int resolution = 8;

int start_time_hour = 6;
int start_time_minute = 0;
int end_time_hour = 1;
int end_time_minute = 0;
int end_time2_hour = 17; // New end time 2
int end_time2_minute = 50;
int fade_duration = 15; // in minutes
int pwm_delay = 5; // Delay for the second PWM, in minutes
int time_shorten = 60; // Time shorten duration in minutes

const int switchPin = 25; // GPIO pin for the switch
bool switchState = false;
bool lastSwitchState = false;
bool adjustmentMade = false;

DateTime lastAdjustmentDay;
DateTime original_end_time;

void setup() {
  Serial.begin(9600);
  Wire.begin(23, 22); // SDA, SCL
  rtc.begin();

  if(!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) {
    Serial.println(F("SSD1306 allocation failed"));
    for(;;);
  }
  display.display();
  delay(2000);

  pinMode(switchPin, INPUT_PULLUP); // Initialize the switch pin
  lastAdjustmentDay = rtc.now();
  original_end_time = DateTime(lastAdjustmentDay.year(), lastAdjustmentDay.month(), lastAdjustmentDay.day(), end_time_hour, end_time_minute, 0);

  ledcSetup(ledcChannel1, freq, resolution);
  ledcAttachPin(pwmPin1, ledcChannel1);
  ledcWrite(ledcChannel1, 255);

  ledcSetup(ledcChannel2, freq, resolution);
  ledcAttachPin(pwmPin2, ledcChannel2);
  ledcWrite(ledcChannel2, 255);
}

void loop() {
  DateTime now = rtc.now();
  DateTime start_time = DateTime(now.year(), now.month(), now.day(), start_time_hour, start_time_minute, 0);
  static DateTime end_time = DateTime(now.year(), now.month(), now.day(), end_time_hour, end_time_minute, 0);
  DateTime end_time2 = DateTime(now.year(), now.month(), now.day(), end_time2_hour, end_time2_minute, 0);

  // Read the switch state
  switchState = digitalRead(switchPin);

  // Check if it's the start time of the day and if adjustment hasn't been made yet
  if (now >= start_time && !adjustmentMade) {
    if (switchState && !lastSwitchState) {
      // Decrease end time by 1 hour each day until it reaches end_time2
      if (end_time - TimeSpan(1, 0, 0, 0) >= end_time2) {
        end_time = end_time - TimeSpan(1, 0, 0, 0); // Decrease by 1 hour
      } else {
        end_time = end_time2; // Set to end_time2 if it's less than an hour away
      }
      adjustmentMade = true;
    } else {
      // Reset end_time to original value if switch is not toggled
      end_time = original_end_time;
    }
  }

  // Reset adjustment flag at the end of the day
  if (now.hour() == 23 && now.minute() == 59) {
    adjustmentMade = false;
  }

  lastSwitchState = switchState; // Update the last switch state

  // PWM and OLED update logic
  int pwm_value1 = calculatePWM1(now.unixtime(), start_time.unixtime(), end_time.unixtime(), fade_duration * 60);
  ledcWrite(ledcChannel1, pwm_value1);

  int pwm_value2 = calculatePWM2(now.unixtime(), start_time.unixtime(), end_time.unixtime(), fade_duration * 60, pwm_delay * 60);
  ledcWrite(ledcChannel2, pwm_value2);

  updateOLED(now, start_time_hour, start_time_minute, end_time, fade_duration, pwm_delay, pwm_value1, pwm_value2, switchState, time_shorten, end_time2);
  delay(1000);
}



int calculatePWM1(long current, long start, long end, long duration) {
  if (current >= start && current < start + duration) {
      return map(current - start, 0, duration, 255, 0);
    } else if (current >= end - duration && current < end) {
      return map(current - (end - duration), 0, duration, 0, 255);
  } else if (current >= start + duration && current < end - duration) {
  return 0;
  }
  return 255;
}
int calculatePWM2(long current, long start, long end, long duration, long delay) {
  if (current >= start + delay && current < start + duration + delay) {
  return map(current - start - delay, 0, duration, 255, 0);
  } else if (current >= end - duration - delay && current < end - delay) {
  return map(current - (end - duration - delay), 0, duration, 0, 255);
  } else if (current >= start + duration + delay && current < end - duration - delay) {
  return 0;
  }
  return 255;
}

void updateOLED(const DateTime& now, int startHour, int startMinute, const DateTime& currentEndTime, int fadeDuration, int led2Delay, int pwm1, int pwm2, bool switchState, int timeShorten, const DateTime& end_time2) {
  display.clearDisplay();
  display.setTextSize(1);
  display.setTextColor(SSD1306_WHITE);
  display.setCursor(0,0);

  display.print("Time: ");
  display.print(now.hour());
  display.print(":");
  display.println(now.minute());

  display.print("Start: ");
  display.print(startHour);
  display.print(":");
  display.println(startMinute);

  display.print("End: ");
  display.print(currentEndTime.hour());
  display.print(":");
  display.println(currentEndTime.minute());

  display.print("Fade:");
  display.print(fadeDuration);
  display.print("min ");
  display.print("Delay:");
  display.print(led2Delay);
  display.println("min");

  display.print("PWM1: ");
  display.print(pwm1);
  display.print("  ");
  display.print("PWM2: ");
  display.println(pwm2);

  display.print("Switch: ");
  display.println(switchState ? "Veg" : "Flow");

  display.print("Shorten: ");
  display.print(timeShorten);
  display.println("min");

  DateTime nextDayEndTime = currentEndTime;
  if (switchState) {
    if (nextDayEndTime - TimeSpan(1, 0, 0, 0) >= end_time2) {
      nextDayEndTime = nextDayEndTime - TimeSpan(1, 0, 0, 0); // Decrease by 1 hour
    } else {
      nextDayEndTime = end_time2; // Set to end_time2 if it's less than an hour away
    }
  }

  display.print("Next End: ");
  display.print(nextDayEndTime.hour());
  display.print(":");
  display.println(nextDayEndTime.minute());
  display.display();
}