/*
 * Copyright (c) 2015-2020,2022 Josef 'Jeff' Sipek <jeffpc@josefsipek.net>
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

#include "dir.h"

#include <jeffpc/time.h>

int dir_create(struct txn *txn, struct objver *dirver, const char *name,
	       uint32_t owner, uint32_t group, uint16_t mode,
	       struct noid *_child)
{
	const uint64_t now = gettime();
	struct nattr attrs = {
		.mode = mode,
		.nlink = 1, /* even new dirs start with link count of 1 */
		.size = NATTR_ISDIR(mode) ? DIR_BLOCK_SIZE : 0,
		.atime = now,
		.btime = now,
		.ctime = now,
		.mtime = now,
		.owner = owner,
		.group = group,
	};
	uint8_t raw[DIR_BLOCK_SIZE];
	struct objver *child;
	struct ndirent_mem ent;
	bool update_existing;
	uint16_t ndirents;
	uint64_t diroff;
	int ret;

	ASSERT(!NATTR_ISGRAFT(mode));

	ret = dir_lookup_entry(dirver, name, raw, &ent, &diroff, &ndirents);
	if (ret) {
		/* error or didn't find anything */
		if (ret != -ENOENT)
			return ret;

		update_existing = false;
	} else {
		/* found something */
		if (!ent.all_deleted)
			return -EEXIST;

		update_existing = true;
	}

	/* create the child */
	child = obj_create(txn, &attrs, &dirver->obj->oid);
	if (IS_ERR(child))
		return PTR_ERR(child);

	/* if the child is a directory, write out empty directory contents */
	if (NATTR_ISDIR(child->attrs.mode)) {
		uint8_t raw[DIR_BLOCK_SIZE];
		struct buffer contents;
		ssize_t ret2;

		buffer_init_static(&contents, raw, sizeof(raw), sizeof(raw),
				   true);

		ret = obj_make_dir_buffer(noid_get_allocator(&child->obj->oid),
					  noid_get_uniq(&child->obj->oid),
					  noid_get_allocator(&dirver->obj->oid),
					  noid_get_uniq(&dirver->obj->oid),
					  &contents);
		if (ret)
			goto err;

		ret2 = obj_write(txn, child, raw, sizeof(raw), 0);
		if (ret2 < 0) {
			ret = ret2;
			goto err;
		}

		if (ret2 != sizeof(raw)) {
			ret = -EIO;
			goto err;
		}
	}

	/* add dirent to parent dir */
	if (!update_existing) {
		ret = dir_add_dirent(txn, dirver, name, mode, &child->obj->oid);
		if (ret)
			goto err;
	} else {
		ret = dir_update_dirent(txn, dirver, raw, diroff, ndirents,
					name, mode, &child->obj->oid);
		if (ret)
			goto err;
	}

	/*
	 * We don't track nlinks on directories (it is always 1), but if we
	 * did we'd increment the parent dir's link count here.
	 */

	*_child = child->obj->oid;

	ret = 0;

err:
	obj_putref(child->obj);

	return ret;
}