/*
 * SPDX-FileCopyrightText: 2021 Espressif Systems (Shanghai) CO LTD
 *
 * SPDX-License-Identifier: CC0
 */

#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include "esp_vfs.h"
#include "esp_vfs_fat.h"
#include "esp_system.h"
#include "sdkconfig.h"

static const char *TAG = "example";


// Mount path for the partition
const char *base_path = "/spiflash";

void app_main(void)
{
    ESP_LOGI(TAG, "Mounting FAT filesystem");
    // To mount device we need name of device partition, define base_path
    // and allow format partition in case if it is new one and was not formatted before
    const esp_vfs_fat_mount_config_t mount_config = {
            .max_files = 4,
            .format_if_mount_failed = false,
            .allocation_unit_size = CONFIG_WL_SECTOR_SIZE
    };
    esp_err_t err = esp_vfs_fat_rawflash_mount(base_path, "storage", &mount_config);
    if (err != ESP_OK) {
        ESP_LOGE(TAG, "Failed to mount FATFS (%s)", esp_err_to_name(err));
        return;
    }
    // Open file for reading
    ESP_LOGI(TAG, "Reading file");
    FILE *f = fopen("/spiflash/sub/test.txt", "rb");
    if (f == NULL) {
        ESP_LOGE(TAG, "Failed to open file for reading");
        return;
    }
    char line[128];
    fgets(line, sizeof(line), f);
    fclose(f);
    // strip newline
    char *pos = strchr(line, '\n');
    if (pos) {
        *pos = '\0';
    }
    ESP_LOGI(TAG, "Read from file: '%s'", line);

    // Unmount FATFS
    ESP_LOGI(TAG, "Unmounting FAT filesystem");
    ESP_ERROR_CHECK( esp_vfs_fat_rawflash_unmount(base_path, "storage"));

    ESP_LOGI(TAG, "Done");
}