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#include "BluetoothA2DPSink.h"  // Include the A2DP sink library
#include "driver/i2s.h"         // Include the I2S driver library

BluetoothA2DPSink a2dp_sink;   // Create A2DP sink instance

// I2S configuration constants
#define I2S_NUM         I2S_NUM_0      // Use I2S peripheral 0
#define I2S_SAMPLE_RATE 44100          // Set audio sample rate to 44.1kHz
#define I2S_BITS        I2S_BITS_PER_SAMPLE_16BIT  // Set 16-bit audio depth
#define I2S_CHANNELS    I2S_CHANNEL_FMT_RIGHT_LEFT // Set stereo (2 channels)
#define I2S_PIN_DATA    33             // Set I2S data pin (GPIO 33)
#define I2S_PIN_BCLK    25             // Set I2S bit clock pin (GPIO 25)
#define I2S_PIN_LRCLK   26             // Set I2S left-right clock pin (GPIO 26)
#define NMUTE_PIN       32             // Pin to control mute functionality

// Function to configure I2S interface
void setup_i2s() {
    // Configure I2S with required settings
    i2s_config_t i2s_config = {
        .mode = (i2s_mode_t)(I2S_MODE_MASTER | I2S_MODE_TX),  // I2S as master and transmitter
        .sample_rate = I2S_SAMPLE_RATE,  // Set sample rate
        .bits_per_sample = I2S_BITS,    // Set bits per sample
        .channel_format = I2S_CHANNELS, // Set stereo channel format
        .communication_format = I2S_COMM_FORMAT_I2S_MSB,  // Set MSB communication format
        .intr_alloc_flags = 0,          // No interrupt flags
        .dma_buf_count = 8,             // DMA buffer count
        .dma_buf_len = 64,              // DMA buffer length
        .use_apll = false               // Do not use APLL (Audio PLL)
    };

    // Configure I2S pin assignments
    i2s_pin_config_t pin_config = {
        .bck_io_num = I2S_PIN_BCLK,      // Bit clock pin
        .ws_io_num = I2S_PIN_LRCLK,      // Word select pin
        .data_out_num = I2S_PIN_DATA,    // Data output pin
        .data_in_num = I2S_PIN_NO_CHANGE // No input data pin
    };

    // Install I2S driver and configure the pins
    i2s_driver_install(I2S_NUM, &i2s_config, 0, NULL);
    i2s_set_pin(I2S_NUM, &pin_config);
}

// Callback function to process incoming audio data and send it to I2S
void read_data_stream(const uint8_t *data, uint32_t length) {
    size_t bytes_written;
    // Write received audio data to I2S for output
    i2s_write(I2S_NUM, data, length, &bytes_written, portMAX_DELAY);

    // Serial debug print statements have been removed to reduce output noise
}

void setup() {
    // Set up mute control pin
    pinMode(NMUTE_PIN, OUTPUT);
    digitalWrite(NMUTE_PIN, HIGH); // Enable audio output by setting pin high

    setCpuFrequencyMhz(80);  // Reduce CPU frequency to 80 MHz for power saving

    // Initialize the I2S interface
    setup_i2s();

    // Start A2DP sink with the name "GOLF G60" and no authentication (false)
    a2dp_sink.set_stream_reader(read_data_stream, false);
    a2dp_sink.start("GOLF G60", false);
}

void loop() {
    delay(1000);  // Main loop does nothing; just delays to keep the program running
}