#include "infra/I2S.h"
#define SAMPLE_RATE (16000)
#define PIN_I2S_BCLK (GPIO_NUM_26)
#define PIN_I2S_LRC (GPIO_NUM_25)
#define PIN_I2S_DIN (GPIO_NUM_3)
#define PIN_I2S_DOUT (GPIO_NUM_22)
#define PIN_I2S_MCK (GPIO_NUM_0)

// This I2S specification : 
//  -   LRC high is channel 2 (right).
//  -   LRC signal transitions once each word.
//  -   DATA is valid on the CLOCK rising edge.
//  -   Data bits are MSB first.
//  -   DATA bits are left-aligned with respect to LRC edge.
//  -   DATA bits are right-shifted by one with respect to LRC edges.
I2S::I2S(MicType micType) {
  if (micType == M5GO || micType == M5STACKFIRE ) {
    BITS_PER_SAMPLE = I2S_BITS_PER_SAMPLE_16BIT;
    i2s_config_t i2s_config = {
      .mode = (i2s_mode_t)(I2S_MODE_MASTER | I2S_MODE_RX | I2S_MODE_TX | I2S_MODE_DAC_BUILT_IN | I2S_MODE_ADC_BUILT_IN),
      .sample_rate = SAMPLE_RATE,
      .bits_per_sample = BITS_PER_SAMPLE,
      .channel_format = I2S_CHANNEL_FMT_RIGHT_LEFT,
      .communication_format = (i2s_comm_format_t)(I2S_COMM_FORMAT_I2S_MSB),
      .intr_alloc_flags = 0,
      .dma_buf_count = 2,
      .dma_buf_len = 1024
    };
    i2s_driver_install(I2S_NUM_0, &i2s_config, 0, NULL);
    i2s_set_adc_mode(ADC_UNIT_1, ADC1_CHANNEL_6);
    i2s_set_clk(I2S_NUM_0, SAMPLE_RATE, BITS_PER_SAMPLE, I2S_CHANNEL_STEREO);
    i2s_adc_enable(I2S_NUM_0);
  }
  else if (micType == ADMP441 || micType == ICS43434 ) {
    BITS_PER_SAMPLE = I2S_BITS_PER_SAMPLE_16BIT;// I2S_BITS_PER_SAMPLE_32BIT;
    i2s_config_t i2s_config = {
      .mode = (i2s_mode_t)(I2S_MODE_MASTER | I2S_MODE_RX),
      .sample_rate = SAMPLE_RATE,
      .bits_per_sample = BITS_PER_SAMPLE,
      .channel_format = I2S_CHANNEL_FMT_RIGHT_LEFT,
      .communication_format = (i2s_comm_format_t)(I2S_COMM_FORMAT_I2S | I2S_COMM_FORMAT_I2S_MSB),
      .intr_alloc_flags = 0,
      .dma_buf_count = 16,
      .dma_buf_len = 60
    };

    i2s_pin_config_t pin_config;

    pin_config.bck_io_num = PIN_I2S_BCLK;
    pin_config.ws_io_num = PIN_I2S_LRC;
    pin_config.data_out_num = I2S_PIN_NO_CHANGE;
    pin_config.data_in_num = PIN_I2S_DIN;
    pin_config.mck_io_num = PIN_I2S_MCK;

    i2s_driver_install(I2S_NUM_0, &i2s_config, 0, NULL);
    i2s_set_pin(I2S_NUM_0, &pin_config);
    i2s_set_clk(I2S_NUM_0, SAMPLE_RATE, BITS_PER_SAMPLE, I2S_CHANNEL_STEREO);
  }
}

int I2S::Read(char* data, int numData) {
  size_t bytes_read;

  if (i2s_read(I2S_NUM_0, (char *)data, numData, &bytes_read, portMAX_DELAY)) {
    return (int)bytes_read;
  }

  return -1;
}

int I2S::GetBitPerSample() {
  return (int)BITS_PER_SAMPLE;
}