#include "usb_cdc_log.h"

#include <stdarg.h>
#include <stdio.h>

#include "esp_check.h"
#include "esp_log.h"
#include "tinyusb.h"
#include "tusb_cdc_acm.h"

static const char *TAG = "usb_log";

static bool s_initialized;
static bool s_host_ready;
static vprintf_like_t s_prev_vprintf;

static int usb_cdc_vprintf(const char *fmt, va_list args)
{
    if (s_host_ready) {
        char buffer[256];
        va_list args_copy;
        va_copy(args_copy, args);
        int len = vsnprintf(buffer, sizeof(buffer), fmt, args_copy);
        va_end(args_copy);
        if (len > 0) {
            if (len >= (int)sizeof(buffer)) {
                len = sizeof(buffer) - 1;
            }
            if (tinyusb_cdcacm_write_queue(TINYUSB_CDC_ACM_0, (const uint8_t *)buffer, len) == ESP_OK) {
                tinyusb_cdcacm_write_flush(TINYUSB_CDC_ACM_0, 0);
            }
        }
        return len;
    }

    if (s_prev_vprintf) {
        va_list args_copy;
        va_copy(args_copy, args);
        int ret = s_prev_vprintf(fmt, args_copy);
        va_end(args_copy);
        return ret;
    }
    return 0;
}

static void usb_cdc_line_state_changed_callback(int itf, cdcacm_event_t *event)
{
    (void)itf;
    s_host_ready = event->line_state_changed_data.dtr;
    if (s_host_ready) {
        const char banner[] = "\r\nwatch-watch log over USB CDC\r\n";
        tinyusb_cdcacm_write_queue(TINYUSB_CDC_ACM_0, (const uint8_t *)banner, sizeof(banner) - 1);
        tinyusb_cdcacm_write_flush(TINYUSB_CDC_ACM_0, 0);
    }
}

bool usb_cdc_log_ready(void)
{
    return s_host_ready;
}

esp_err_t usb_cdc_log_init(void)
{
    if (s_initialized) {
        return ESP_OK;
    }

    const tinyusb_config_t tusb_cfg = {
        .device_descriptor = NULL,
        .string_descriptor = NULL,
        .external_phy = false,
#if (TUD_OPT_HIGH_SPEED)
        .fs_configuration_descriptor = NULL,
        .hs_configuration_descriptor = NULL,
        .qualifier_descriptor = NULL,
#else
        .configuration_descriptor = NULL,
#endif
    };

    ESP_RETURN_ON_ERROR(tinyusb_driver_install(&tusb_cfg), TAG, "TinyUSB init failed");

    const tinyusb_config_cdcacm_t acm_cfg = {
        .usb_dev = TINYUSB_USBDEV_0,
        .cdc_port = TINYUSB_CDC_ACM_0,
        .rx_unread_buf_sz = 64,
        .callback_rx = NULL,
        .callback_rx_wanted_char = NULL,
        .callback_line_state_changed = usb_cdc_line_state_changed_callback,
        .callback_line_coding_changed = NULL,
    };
    ESP_RETURN_ON_ERROR(tusb_cdc_acm_init(&acm_cfg), TAG, "CDC init failed");

    s_prev_vprintf = esp_log_set_vprintf(usb_cdc_vprintf);
    s_initialized = true;
    ESP_LOGI(TAG, "ESP_LOG перенаправлено в USB CDC");
    return ESP_OK;
}