#include <Arduino.h>
#include <Wire.h>
#include <DFRobotDFPlayerMini.h> // Include the library for DFPlayerMini voice module

#define LDR_PIN A0 // Pin connected to the LDR sensor
#define THRESHOLD 500 // Adjust this threshold according to ambient light conditions
#define AMP_OUT_PIN 23 // Pin connected to the amplifier module

DFRobotDFPlayerMini dfplayer; // Create an instance of DFPlayerMini

void setup() {
  Serial.begin(115200);
  
  // Initialize DFPlayerMini
  if (!dfplayer.begin(Serial2)) {  // Serial2 is connected to TX2 and RX15
    Serial.println("Unable to begin:");
    Serial.println("1.Please recheck the connection!");
    Serial.println("2.Please insert the SD card!");
    while(true);
  }
  Serial.println("DFPlayer Mini online.");

  // Set the baud rate for the voice module
  dfplayer.setTimeOut(500); //Set serial communication time out 500ms
  dfplayer.volume(20);  //Set volume value (0~30).
  
  pinMode(LDR_PIN, INPUT);
  pinMode(AMP_OUT_PIN, OUTPUT);
}

void loop() {
  int lightLevel = analogRead(LDR_PIN);
  
  if (lightLevel < THRESHOLD) {
    // Dark place detected
    digitalWrite(AMP_OUT_PIN, HIGH); // Turn on the amplifier
    delay(500); // Delay before playing the message to ensure the amplifier is ready
    
    // Play the voice message
    dfplayer.playMp3Folder(1); // Assume voice message "You have entered a dark place" is stored in folder 1
    delay(5000); // Adjust delay to match the length of the message
    
    digitalWrite(AMP_OUT_PIN, LOW); // Turn off the amplifier
  } else {
    // Bright place detected
    digitalWrite(AMP_OUT_PIN, LOW); // Turn off the amplifier
  }
  
  delay(500); // Adjust delay according to your requirement
}