/*
    umka_fuse: User-Mode KolibriOS developer tools, the filesystem
    Copyright (C) 2018--2020  Ivan Baravy <dunkaist@gmail.com>

    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 2 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program.  If not, see <https://www.gnu.org/licenses/>.
*/

#define FUSE_USE_VERSION 31

#include <fuse.h>
#include <stdio.h>
#include <string.h>
#include <errno.h>
#include <fcntl.h>
#include <stddef.h>
#include <stdlib.h>
#include <time.h>
#include <assert.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include <fcntl.h>
#include "vdisk.h"
#include "umka.h"

#define DIRENTS_TO_READ 100

static void bdfe_to_stat(bdfe_t *kf, struct stat *st) {
//    if (kf->attr & KF_FOLDER) {
    if (st) {
        st->st_mode = S_IFDIR | 0755;
        st->st_nlink = 2;
    } else {
        st->st_mode = S_IFREG | 0644;
        st->st_nlink = 1;
        st->st_size = kf->size;
    }
    st->st_atime = kos_time_to_epoch(&(kf->atime));
    st->st_mtime = kos_time_to_epoch(&(kf->mtime));
    st->st_ctime = kos_time_to_epoch(&(kf->ctime));
}

static void *umka_init(struct fuse_conn_info *conn,
                       struct fuse_config *cfg) {
        (void) conn;
        cfg->kernel_cache = 1;
        return NULL;
}

static int umka_getattr(const char *path, struct stat *stbuf,
                        struct fuse_file_info *fi) {
    (void) fi;
    int res = 0;

    bdfe_t file;
    f7080s5arg_t fX0 = {.sf = 5, .flags = 0, .buf = &file, .u = {.f80 = {.path_encoding = UTF8, .path = path}}};
    f7080ret_t r;
    umka_sys_lfn(&fX0, &r, F80);

    bdfe_to_stat(&file, stbuf);
//   res = -ENOENT;
    return res;
}

static int umka_readdir(const char *path, void *buf, fuse_fill_dir_t filler,
                        off_t offset, struct fuse_file_info *fi,
                        enum fuse_readdir_flags flags) {
    (void) offset;      // TODO
    (void) fi;
    (void) flags;

    f7080s1info_t *dir = (f7080s1info_t*)malloc(sizeof(f7080s1info_t) + BDFE_LEN_UNICODE * DIRENTS_TO_READ);
    f7080s1arg_t fX0 = {.sf = 1, .offset = 0, .encoding = UTF8, .size = DIRENTS_TO_READ, .buf = dir, .u = {.f80 = {.path_encoding = UTF8, .path = path}}};
    f7080ret_t r;
    umka_sys_lfn(&fX0, &r, F80);
    bdfe_t *bdfe = dir->bdfes;
    for (size_t i = 0; i < dir->cnt; i++) {
        filler(buf, bdfe->name, NULL, 0, 0);
        bdfe = (bdfe_t*)((uintptr_t)bdfe + BDFE_LEN_UNICODE);
    }
    free(dir);
    return 0;
}

static int umka_open(const char *path, struct fuse_file_info *fi) {
//        if (strcmp(path+1, "blah") != 0)
//                return -ENOENT;
        (void) path;

        if ((fi->flags & O_ACCMODE) != O_RDONLY)
                return -EACCES;

        return 0;
}

static int umka_read(const char *path, char *buf, size_t size, off_t offset,
                     struct fuse_file_info *fi) {
    (void) fi;

    f7080s0arg_t fX0 = {.sf = 0, .offset = offset, .count = size, .buf = buf, .u = {.f80 = {.path_encoding = UTF8, .path = path}}};
    f7080ret_t r;
    umka_sys_lfn(&fX0, &r, F80);
    return size;
}

static struct fuse_operations umka_oper = {
        .init           = umka_init,
        .getattr        = umka_getattr,
        .readdir        = umka_readdir,
        .open           = umka_open,
        .read           = umka_read,
};

int main(int argc, char *argv[]) {
        if (argc != 3) {
                printf("usage: umka_fuse dir img\n");
                exit(1);
        }
        kos_init();
        void *userdata = vdisk_init(argv[2], 1, 0u);
        void *vdisk = disk_add(&vdisk_functions, "hd0", userdata, 0);
        disk_media_changed(vdisk, 1);
        return fuse_main(argc-1, argv, &umka_oper, NULL);
}