#include "fsctl/fugue/fat.h"
#include "fsctl/fugue/sector.h"
#include "fsctl/fugue/utils.h"

//---
// Public
//---

/* fugue_fat_is_vaild() : Check the complet FATs validity */
int fugue_fat_is_vaild(fugue_fs_t *fs)
{
    uint16_t *cluster_map;
    uint32_t *sector;
    uint16_t cluster;

    /* check FATID and root value */
    sector = (void *)fs->_private.fat0;
    if (((uint8_t*)sector)[0] != 0xf8 || ((uint8_t*)sector)[1] != 0xff)
        return -1;
    if (((uint8_t*)sector)[2] != 0xff || ((uint8_t*)sector)[3] != 0xff)
        return -1;
    sector = (void *)fs->_private.fat1;
    if (((uint8_t*)sector)[0] != 0xf8 || ((uint8_t*)sector)[1] != 0xff)
        return -1;
    if (((uint8_t*)sector)[2] != 0xff || ((uint8_t*)sector)[3] != 0xff)
        return -1;

    /* check complet valid FAT
     * @note
     * - full Fugue FAT area take 5120 bytes -> 10x512 -> 10 sectors
     * - also check the root reserved sectors */
    sector = (void*)fs->_private.fat0;
    for (int i = 0 ; i < 10 + fs->props.sector_root_nb ; i++)
    {
        if (fugue_sector_is_invalid(sector))
            return -1;
        sector = (void *)((uintptr_t)sector + 512);
    }

    /* follows each cluster and check that all sector are used */
    cluster_map = (void *)fs->_private.fat1;
    fs->props.cluster_resv = 0;
    fs->props.cluster_free = 0;
    fs->props.cluster_used = 0;
    fs->props.cluster_dead = 0;
    fs->props.cluster_error = 0;
    for (int i = 1 ; i < 256 ; i++)
    {
        cluster = FAT_WORD(cluster_map[i]);
        if (cluster == 0x0000) {
            fs->props.cluster_free += 1;
            continue;
        }
        if (cluster == 0x0001) {
            fs->props.cluster_resv += 1;
            continue;
        }
        if (cluster == 0xfff7) {
            fs->props.cluster_dead += 1;
            continue;
        }
        if (cluster >= 0xfff8) {
            fs->props.cluster_used += 1;
            continue;
        }
        if (cluster < (fs->props.cluster_nb + 1)) {
            fs->props.cluster_used += 1;
            continue;
        }
        fs->props.cluster_error += 1;
        fs->props.test = cluster;
    }
    return 0;
}