// Fnu Shoaib Ahmed, 652420658, fahme8
// Lab 4 - Photoresistor (LDR – Light Dependent Resistor)

// Description - In this lab we are trying to adjust a photo sensor where it tells us how bright is it in the area.

// Assumptions - I expected the potentiometer to work as increase and decrease the display brightness, and the wires to work correctly.

// References - I used the prelab links to setup my photoresistor on breadboard and the setup of potentiometer.


#include <LiquidCrystal.h>

// Initialize the LCD library with the pins (RS, E, D4, D5, D6, D7)
LiquidCrystal lcd(12, 11, 5, 4, 3, 2);

int photoresistorPin = A0;  // Pin where the photoresistor is connected
long previousMillis = 0;

void setup() {
  lcd.begin(16, 2);  // Set up the LCD with 16 columns and 2 rows
  pinMode(photoresistorPin, INPUT);  // Set the photoresistor pin as input
  Serial.begin(9600);  // Begin serial communication for debugging
}

void loop() {
  int lightValue = analogRead(photoresistorPin);  // Read the value from the photoresistor

  // Map the lightValue to predefined text
  String lightLevel;
  if (lightValue < 50) {
    lightLevel = "dark      ";  // Adding spaces to clear old characters
  } else if (lightValue < 100) {
    lightLevel = "partially dark";
  } else if (lightValue < 200) {
    lightLevel = "medium       ";
  } else if (lightValue < 400) {
    lightLevel = "fully lit    ";
  } else {
    lightLevel = "brightly lit ";
  }

  // Clear the LCD before writing new content
  lcd.clear();
  
  // Display the light level on the LCD
  lcd.setCursor(0, 0);  // Start at the first line
  lcd.print("Light: ");
  lcd.print(lightLevel);

  // Display the time since reset on the second line
  long currentMillis = millis();  // Get the current time
  lcd.setCursor(0, 1);  // Move to the second line
  lcd.print("Time: ");
  lcd.print(currentMillis);

  delay(100);  // Small delay to prevent flooding the LCD
}