#define oneSecond 1000
#define halfSecond 500
#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>
#include <Adafruit_NeoPixel.h>
int s_pin = 9;
int n_leds = 10;
//Adafruit_NeoPixel strip = Adafruit_NeoPixel(n_leds, s_pin);

#define PIXEL_PIN       9      // Arduino pin connected to the NeoPixel's Data Input (DIN)
#define PIXEL_COUNT     10      // Total number of pixels on your strip
const int ANALOG_INPUT_PIN = A1; // Analog pin to read the sensor/potentiometer

// Define the colors as 32-bit values (R, G, B)
// The NeoPixel library uses 0-255 for each color component
#define COLOR_GREEN  strip.Color(0, 255, 0)     // Bright Green
#define COLOR_ORANGE strip.Color(255, 128, 0)    // Orange (mix of Red and Green)
#define COLOR_RED    strip.Color(255, 0, 0)      // Red
#define COLOR_OFF    strip.Color(0, 0, 0)       // Off/Black

// Create the NeoPixel object
// NEO_GRB + NEO_KHZ800 is the most common setting for WS2812B strips
Adafruit_NeoPixel strip(PIXEL_COUNT, PIXEL_PIN, NEO_GRB + NEO_KHZ800);


#define SCREEN_WIDTH 128     // OLED display width, in pixels
#define SCREEN_HEIGHT 64     // OLED display height, in pixels
#define OLED_RESET -1        // Reset pin # (or -1 if sharing Arduino reset pin)
#define SCREEN_ADDRESS 0x3C  ///< See datasheet for Address; 0x3D for 128x64, 0x3C for 128x32
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);

const int rest = A0;
const int ten_Min = 3;
const int twenty_Min = A2;
const int thirty_Min = A3;
const int forty_Min = 2;
const int fifty_Min = 5;
const int Hour = 6;
const int buzz = 4;
const int relay = 8;
int hrs = 0;
int Min = 0;
int sec = 0;

bool RUN = true;
bool min_flag = true;
bool hrs_flag = true;
void timer(void);
unsigned long tNow, flowRateTime;
void setup() {
  Serial.begin(115200);
  if (!display.begin(SSD1306_SWITCHCAPVCC, SCREEN_ADDRESS)) {
    Serial.println(F("SSD1306 allocation failed"));
  }

  display.clearDisplay();

  display.setTextSize(2);  // Draw 2X-scale text
  display.setTextColor(SSD1306_WHITE);
  display.setCursor(10, 20);
  display.println(F("CO2inhale "));
  display.display();
  delay(2000);

  display.clearDisplay();
  pinMode(rest, INPUT_PULLUP);
  pinMode(ten_Min, INPUT_PULLUP);
  pinMode(twenty_Min, INPUT_PULLUP);
  pinMode(thirty_Min, INPUT_PULLUP);
  pinMode(forty_Min, INPUT_PULLUP);
  pinMode(fifty_Min, INPUT_PULLUP);
  pinMode(Hour, INPUT_PULLUP);

  pinMode(buzz, OUTPUT);
  pinMode(relay, OUTPUT);
  digitalWrite(relay, LOW);
  digitalWrite(buzz, LOW);

  strip.begin(); // Initialize the NeoPixel strip object
  strip.show();  // Initialize all pixels to 'off'

  outEndTone();
}

void loop() {
  readFlow();
  dispSetTime();
  if (digitalRead(ten_Min) == LOW) {
    Min = 5; sec = 0;
    delay(100);
    timer();
  } else if (digitalRead(twenty_Min) == LOW) {
    Min = 10; sec = 0;
    delay(100);
    timer();
  } else if (digitalRead(thirty_Min) == LOW) {
    Min = 15; sec = 0;
    delay(100);
    timer();
  } else if (digitalRead(forty_Min) == LOW) {
    Min = 20; sec = 0;
    delay(100);
    timer();
  } else if (digitalRead(fifty_Min) == LOW) {
    Min = 25; sec = 0;
    delay(100);
    timer();
  } else if (digitalRead(Hour) == LOW) {
    Min = 30; sec = 0;
    delay(100);
    timer();
  }
}

void dispSetTime() {
  display.clearDisplay();
  display.setTextSize(2);  // Draw 2X-scale text
  display.setTextColor(SSD1306_WHITE);
  display.setCursor(15, 20);
  display.println(F("Set Time"));
  display.display();

}

void timer(void) {
  display.clearDisplay();
  RUN = true;
  tNow = millis();
  while (RUN) {
    digitalWrite(relay, HIGH);
    dispTime();

    if((millis()-tNow)>=oneSecond){
      tNow = millis();
      updateTime();
    }   
    if(millis()-flowRateTime>=halfSecond){
      flowRateTime = millis();
      readFlow();
    }
    

    if (Min == 0 && sec == 0) {
      digitalWrite(relay, LOW);
      display.clearDisplay();
      display.setTextSize(2);  // Draw 2X-scale text
      display.setTextColor(SSD1306_WHITE);
      display.setCursor(1, 0);
      display.println(F("Time Out"));
      display.display();
      delay(200);
      RUN = false;
      outEndTone();
    }

    if (digitalRead(rest) == LOW) {
      digitalWrite(relay, LOW);
      display.clearDisplay();
      display.setTextSize(2);  // Draw 2X-scale text
      display.setTextColor(SSD1306_WHITE);
      display.setCursor(1, 0);
      display.println(F("Resetting"));
      display.display();
      delay(1000);
      RUN = false;
    }

  }
}

void dispTime() {
  display.clearDisplay();
  display.setTextSize(4);  // Draw 2X-scale text
  display.setTextColor(SSD1306_WHITE);
  if(Min>=10)
    display.setCursor(5, 20);
  else
    display.setCursor(15, 20);

  display.print(Min);

  display.print(":");
  display.setTextSize(4);  // Draw 2X-scale text
  display.setTextColor(SSD1306_WHITE);

  if (sec <= 9)display.print("0");
  display.print(sec);
  display.display();
}

void updateTime(){
  sec = sec - 1;   
    if (sec == -1) {
      if(Min !=0){
      sec = 59;
      Min = Min - 1;
      }
      else{
        sec = 0;
        Min = 0;
        digitalWrite(relay,LOW);
        dispTime();
        delay(oneSecond);
      }
    }   
}
void outEndTone() {
  tone(buzz, 440, 100);
  delay(200);
  tone(buzz, 440, 100);
  delay(200);
  tone(buzz, 440, 100);
  delay(200);
  tone(buzz, 440, 1000);
  delay(1000);
}

void readFlow(){
  // 1. Read the analog value (0 to 1023)
  int analogValue = analogRead(ANALOG_INPUT_PIN);

  // 2. Map the analog value (0-1023) to the number of pixels to light (0-10)
  // This gives a sequential bar-graph effect.
  int pixelsToLight = map(analogValue, 0, 1023, 0, PIXEL_COUNT);

  // 3. Control the pixels and set their color based on the segment
  for (int i = 0; i < PIXEL_COUNT; i++) {
    uint32_t colorToSet = COLOR_OFF; // Start by assuming the pixel is off

    if (i < pixelsToLight) {
      // The pixel should be ON. Determine its color based on its index (i).
      if (i < 5) {
        // Pixels 0 through 4 (first 5) are GREEN
        colorToSet = COLOR_GREEN;
      } else if (i < (5 + 3)) {
        // Pixels 5 through 7 (next 3) are ORANGE
        colorToSet = COLOR_ORANGE;
      } else {
        // Pixels 8 through 9 (last 2) are RED
        colorToSet = COLOR_RED;
      }
    }
    
    // Set the pixel color (this updates the internal buffer)
    strip.setPixelColor(i, colorToSet);
  }

  // 4. Send the updated colors to the strip hardware
  strip.show(); 

  // Print values for debugging
  Serial.print("Analog: ");
  Serial.print(analogValue);
  Serial.print(" -> Pixels Lit: ");
  Serial.println(pixelsToLight);

  delay(20); // Small delay for smooth operation
}

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