/*
  ESP32 I2S Microphone Sample
  esp32-i2s-mic-sample.ino
  Sample sound from I2S microphone, display on Serial Plotter
  Requires INMP441 I2S microphone

  DroneBot Workshop 2022
  https://dronebotworkshop.com
*/
#include <Arduino.h>
// Include I2S driver
#include <driver/i2s.h>

// Connections to INMP441 I2S microphone
#define I2S_WS 25
#define I2S_SD 33
#define I2S_SCK 32

// Use I2S Processor 0
#define I2S_PORT I2S_NUM_0

// Define input buffer length
#define bufferLen 1024
int16_t sBuffer[bufferLen];

void i2s_install()
{
    // Set up I2S Processor configuration
    const i2s_config_t i2s_config = {
        .mode = i2s_mode_t(I2S_MODE_MASTER | I2S_MODE_RX),
        .sample_rate = 44100,
        .bits_per_sample = i2s_bits_per_sample_t(16),
        .channel_format = I2S_CHANNEL_FMT_ONLY_LEFT,
        .communication_format = i2s_comm_format_t(I2S_COMM_FORMAT_STAND_I2S),
        .intr_alloc_flags = ESP_INTR_FLAG_LEVEL1,
        .dma_buf_count = 4,
        .dma_buf_len = bufferLen,
        .use_apll = false,
        .tx_desc_auto_clear = false,
        .fixed_mclk = 0};

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

void i2s_setpin()
{
    // Set I2S pin configuration
    const i2s_pin_config_t pin_config = {
        .bck_io_num = I2S_SCK,
        .ws_io_num = I2S_WS,
        .data_out_num = -1,
        .data_in_num = I2S_SD};

    i2s_set_pin(I2S_PORT, &pin_config);
}

void setup()
{

    // Set up Serial Monitor
    Serial.begin(115200);
    Serial.println(" ");

    delay(1000);

    // Set up I2S
    i2s_install();
    i2s_setpin();
    i2s_start(I2S_PORT);

    delay(500);
}

void loop()
{

    // False print statements to "lock range" on serial plotter display
    // Change rangelimit value to adjust "sensitivity"
    int rangelimit = 3000;
    Serial.print(rangelimit * -1);
    Serial.print(" ");
    Serial.print(rangelimit);
    Serial.print(" ");

    // Get I2S data and place in data buffer
    size_t bytesIn = 0;
    esp_err_t result = i2s_read(I2S_PORT, &sBuffer, bufferLen, &bytesIn, portMAX_DELAY);

    if (result == ESP_OK)
    {
        // Read I2S data buffer
        int16_t samples_read = bytesIn / 8;
        if (samples_read > 0)
        {
            float mean = 0;
            for (int16_t i = 0; i < samples_read; ++i)
            {
                mean += (sBuffer[i]);
            }

            // Average the data reading
            mean /= samples_read;

            // Print to serial plotter
            Serial.println(mean);

            int recu = bytesIn / sizeof(int32_t);
            for (int i = 0; i < recu; i++)
            {
                Serial.printf("%ld\n", sBuffer[i]);
            }
            // Serial.print(" - ");
            Serial.println(bytesIn);
        }
    }
}