/*
 * UAC2 microphone: feeds WiFi-received audio to USB host.
 *
 * The usb_device_uac component calls our input callback periodically
 * (every CONFIG_UAC_MIC_INTERVAL_MS). We read from the shared ring buffer
 * and hand it to the USB stack. If the ring buffer has insufficient data,
 * we zero-fill the remainder (silence).
 */

#include <string.h>
#include "esp_log.h"
#include "usb_device_uac.h"
#include "usb_audio.h"

#define TAG "uac"

static ring_buf_t *s_rb;

static esp_err_t mic_input_cb(uint8_t *buf, size_t len, size_t *bytes_read, void *ctx)
{
    size_t got = ring_buf_read(s_rb, buf, len);
    if (got < len)
        memset(buf + got, 0, len - got);
    *bytes_read = len;
    return ESP_OK;
}

void usb_audio_init(ring_buf_t *rb)
{
    s_rb = rb;

    uac_device_config_t cfg = {
        .output_cb     = NULL,
        .input_cb      = mic_input_cb,
        .set_mute_cb   = NULL,
        .set_volume_cb = NULL,
        .cb_ctx        = NULL,
    };

    esp_err_t err = uac_device_init(&cfg);
    if (err != ESP_OK) {
        ESP_LOGE(TAG, "uac_device_init failed: %s", esp_err_to_name(err));
        return;
    }

    ESP_LOGI(TAG, "UAC2 mic ready: 48kHz 16-bit stereo");
}