/*
  Wokwi | general
  pilis 5/5/25 8:59 AM
  Okay, so, how can the C code be adjusted so that if the gas sensor is
  at 100 ppm, only the message "Gas Detected" appears?
  https://wokwi.com/projects/429836622322713601

  This project at the end, has to follow these requirements:
  Setting the LED for different colors and notifying this color in an LCD message
  relay activation on gas sensor activation
*/

#include <LiquidCrystal.h>
#include "HX711.h"
#include <TM1637.h>

// LCD Pins (RS, E, D4, D5, D6, D7)
LiquidCrystal lcd(15, 14, 13, 12, 11, 10);

// HX711 Pins (DT, SCK)
HX711 scale;
#define HX711_DT 6
#define HX711_SCK 5

// TM1637 7-Segment Pins
#define TM1637_CLK 2
#define TM1637_DIO 3
TM1637 display(TM1637_CLK, TM1637_DIO);

// RGB LED Pins (common cathode!)
#define RED_PIN 9
#define GREEN_PIN 8
#define BLUE_PIN 7

// Relay and Analog Gas Sensor
#define RELAY_PIN 4
#define GAS_SENSOR_ANALOG A0

int colorChangeCount = 0;
int currentColor = -1;

void setup() {
  Serial.begin(115200);
  lcd.begin(16, 2);
  lcd.print("Initializing...");

  scale.begin(HX711_DT, HX711_SCK);

  display.init();
  display.set(BRIGHT_TYPICAL);

  pinMode(RED_PIN, OUTPUT);
  pinMode(GREEN_PIN, OUTPUT);
  pinMode(BLUE_PIN, OUTPUT);

  pinMode(RELAY_PIN, OUTPUT);

  lcd.clear();
}

void setColor(int colorIndex, const char* colorName) {
  // Only change color if it's different from current
  if (colorIndex == currentColor) return;
  currentColor = colorIndex;

  // Set RGB based on colorIndex: 0=RED, 1=GREEN, 2=BLUE
  digitalWrite(RED_PIN, colorIndex == 0 ? HIGH : LOW);
  digitalWrite(GREEN_PIN, colorIndex == 1 ? HIGH : LOW);
  digitalWrite(BLUE_PIN, colorIndex == 2 ? HIGH : LOW);

  // LCD Row 0: show color
  //lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("Color: ");
  lcd.print(colorName);

  // Increment counter and show on display
  colorChangeCount++;
  int count = colorChangeCount;
  display.display(0, (count / 1000) % 10);
  display.display(1, (count / 100) % 10);
  display.display(2, (count / 10) % 10);
  display.display(3, count % 10);
}

void loop() {
  // Cycle through RED, GREEN, BLUE
  setColor(0, "RED  ");
  delay(2000);

  setColor(1, "GREEN");
  delay(2000);

  setColor(2, "BLUE ");
  delay(2000);

  // get weight value
  float weight = scale.get_units();

  // Read analog gas sensor
  int analogValue = analogRead(GAS_SENSOR_ANALOG);
  float ppm = (analogValue / 1023.0) * 100.0;
  Serial.print("PPM: ");
  Serial.println(ppm);
  Serial.print("Weight value: ");
  Serial.println(weight);
  if (weight > 400) {
    lcd.clear();
    lcd.setCursor(0, 0);
    lcd.print("An object has");
    lcd.setCursor(0, 1);
    lcd.print("been placed.");
  } else {
    //lcd.clear();
    //lcd.setCursor(0, 1);
    //lcd.print("No weight");
  }
  delay(1000);
  // LCD Row 1: Gas status
  lcd.setCursor(0, 1);
  if (ppm > 50) {
    lcd.clear();
    lcd.setCursor(0, 1);
    lcd.print("GAS DETECTED!");
    digitalWrite(RELAY_PIN, HIGH);
  } else {
    lcd.clear();
    lcd.setCursor(0, 1);
    lcd.print("No Gas Detected");
    digitalWrite(RELAY_PIN, LOW);
  }
}