#include <driver/i2s.h>

#define I2S_WS      6   // LRCL (Word Select)
#define I2S_SCK     7   // BCLK (Serial Clock)
#define I2S_SD      8   // DOUT (Serial Data from mic)

#define I2S_PORT    I2S_NUM_0
#define BUFFER_SIZE 2048  // Larger buffer = fewer calls

void setup() {
  Serial.begin(1000000);  // High-speed serial for streaming audio

  // I2S configuration
  const i2s_config_t i2s_config = {
    .mode = i2s_mode_t(I2S_MODE_MASTER | I2S_MODE_RX),
    .sample_rate = 8000,
    .bits_per_sample = I2S_BITS_PER_SAMPLE_32BIT,
    .channel_format = I2S_CHANNEL_FMT_ONLY_LEFT,
    .communication_format = I2S_COMM_FORMAT_I2S,
    .intr_alloc_flags = ESP_INTR_FLAG_LEVEL1,
    .dma_buf_count = 4,
    .dma_buf_len = BUFFER_SIZE / 4,
    .use_apll = false,
    .tx_desc_auto_clear = false,
    .fixed_mclk = 0
  };

  const i2s_pin_config_t pin_config = {
    .bck_io_num = I2S_SCK,
    .ws_io_num = I2S_WS,
    .data_out_num = I2S_PIN_NO_CHANGE,
    .data_in_num = I2S_SD
  };

  i2s_driver_install(I2S_PORT, &i2s_config, 0, NULL);
  i2s_set_pin(I2S_PORT, &pin_config);
}

void loop() {
  uint8_t buffer[BUFFER_SIZE];
  size_t bytes_read;

  if (i2s_read(I2S_PORT, &buffer, BUFFER_SIZE, &bytes_read, portMAX_DELAY) == ESP_OK && bytes_read > 0) {
    for (int i = 0; i < bytes_read; i += 4) {
      int32_t sample_32 = *(int32_t*)&buffer[i];
      int16_t sample_16 = sample_32 >> 12;  // Less aggressive shift

      Serial.write((uint8_t*)&sample_16, 2);
    }
  }
}