/* 
   Unix SMB/CIFS implementation.
   Registry interface
   Copyright (C) Jelmer Vernooij  2004-2007.
   
   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 3 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 <http://www.gnu.org/licenses/>.
*/

#include "includes.h"
#include "registry.h"
#include "lib/ldb/include/ldb.h"
#include "lib/ldb/include/ldb_errors.h"
#include "db_wrap.h"
#include "librpc/gen_ndr/winreg.h"
#include "param/param.h"

static struct hive_operations reg_backend_ldb;

struct ldb_key_data 
{
	struct hive_key key;
	struct ldb_context *ldb;
	struct ldb_dn *dn;
	struct ldb_message **subkeys, **values;
	int subkey_count, value_count;
};

static void reg_ldb_unpack_value(TALLOC_CTX *mem_ctx, struct ldb_message *msg, const char **name, 
								 uint32_t *type, DATA_BLOB *data)
{
	const struct ldb_val *val;
	if (name != NULL)
		*name = talloc_strdup(mem_ctx, ldb_msg_find_attr_as_string(msg, "value", NULL));

	if (type != NULL)
		*type = ldb_msg_find_attr_as_uint(msg, "type", 0);
	val = ldb_msg_find_ldb_val(msg, "data");

	switch (*type)
	{
	case REG_SZ:
	case REG_EXPAND_SZ:
		data->length = convert_string_talloc(mem_ctx, CH_UTF8, CH_UTF16, 
											 val->data, val->length, (void **)&data->data);
		break;

	case REG_DWORD: {
		uint32_t tmp = strtoul((char *)val->data, NULL, 0);
		*data = data_blob_talloc(mem_ctx, &tmp, 4);
		}
		break;

	default:
		*data = data_blob_talloc(mem_ctx, val->data, val->length);
		break;
	}
}

static struct ldb_message *reg_ldb_pack_value(struct ldb_context *ctx, 
						TALLOC_CTX *mem_ctx, const char *name, 
						uint32_t type, DATA_BLOB data)
{
	struct ldb_val val;
	struct ldb_message *msg = talloc_zero(mem_ctx, struct ldb_message);
	char *type_s;

	ldb_msg_add_string(msg, "value", talloc_strdup(mem_ctx, name));

	switch (type) {
	case REG_SZ:
	case REG_EXPAND_SZ:
		val.length = convert_string_talloc(mem_ctx, CH_UTF16, CH_UTF8, 
										   (void *)data.data, data.length, (void **)&val.data);
		ldb_msg_add_value(msg, "data", &val, NULL);
		break;

	case REG_DWORD:
		ldb_msg_add_string(msg, "data", talloc_asprintf(mem_ctx, "0x%x", IVAL(data.data, 0)));
		break;
	default:
		ldb_msg_add_value(msg, "data", &data, NULL);
	}


	type_s = talloc_asprintf(mem_ctx, "%u", type);
	ldb_msg_add_string(msg, "type", type_s); 

	return msg;
}


static int reg_close_ldb_key(struct ldb_key_data *key)
{
	if (key->subkeys != NULL) {
		talloc_free(key->subkeys); 
		key->subkeys = NULL;
	}

	if (key->values != NULL) {
		talloc_free(key->values); 
		key->values = NULL;
	}
	return 0;
}

static struct ldb_dn *reg_path_to_ldb(TALLOC_CTX *mem_ctx, 
									  const struct hive_key *from, 
									  const char *path, const char *add)
{
	TALLOC_CTX *local_ctx;
	struct ldb_dn *ret;
	char *mypath = talloc_strdup(mem_ctx, path);
	char *begin;
	struct ldb_key_data *kd = talloc_get_type(from, struct ldb_key_data);
	struct ldb_context *ldb = kd->ldb;

	local_ctx = talloc_new(mem_ctx);

	if (add) {
		ret = ldb_dn_new(mem_ctx, ldb, add);
	} else {
		ret = ldb_dn_new(mem_ctx, ldb, NULL);
	}
	if (!ldb_dn_validate(ret)) {
		talloc_free(ret);
		talloc_free(local_ctx);
		return NULL;
	}

	while (mypath) {
		char *keyname;

		begin = strrchr(mypath, '\\');

		if (begin) keyname = begin + 1;
		else keyname = mypath;

		if(strlen(keyname)) {
			ldb_dn_add_base_fmt(ret, "key=%s", keyname);
		}

		if(begin) {
			*begin = '\0';
		} else {
			break;
		}
	}

	ldb_dn_add_base(ret, kd->dn);

	talloc_free(local_ctx);

	return ret;
}

static WERROR cache_subkeys(struct ldb_key_data *kd)
{
	struct ldb_context *c = kd->ldb;
	struct ldb_result *res;
	int ret;

	ret = ldb_search(c, kd->dn, LDB_SCOPE_ONELEVEL, "(key=*)", NULL, &res);

	if (ret != LDB_SUCCESS) {
		DEBUG(0, ("Error getting subkeys for '%s': %s\n", ldb_dn_get_linearized(kd->dn), ldb_errstring(c)));
		return WERR_FOOBAR;
	}

	kd->subkey_count = res->count;
	kd->subkeys = talloc_steal(kd, res->msgs);
	talloc_free(res);

	return WERR_OK;
}

static WERROR cache_values(struct ldb_key_data *kd)
{
	struct ldb_context *c = kd->ldb;
	struct ldb_result *res;
	int ret;

	ret = ldb_search(c, kd->dn, LDB_SCOPE_ONELEVEL, "(value=*)", NULL, &res);

	if (ret != LDB_SUCCESS) {
		DEBUG(0, ("Error getting values for '%s': %s\n", ldb_dn_get_linearized(kd->dn), ldb_errstring(c)));
		return WERR_FOOBAR;
	}
	kd->value_count = res->count;
	kd->values = talloc_steal(kd, res->msgs);
	talloc_free(res);
	return WERR_OK;
}


static WERROR ldb_get_subkey_by_id(TALLOC_CTX *mem_ctx, 
						   const struct hive_key *k, uint32_t idx, 
						   const char **name,
						   const char **classname,
						   NTTIME *last_mod_time)
{
	struct ldb_message_element *el;
	struct ldb_key_data *kd = talloc_get_type(k, struct ldb_key_data);

	/* Do a search if necessary */
	if (kd->subkeys == NULL) {
		W_ERROR_NOT_OK_RETURN(cache_subkeys(kd));
	} 

	if (idx >= kd->subkey_count) 
		return WERR_NO_MORE_ITEMS;

	el = ldb_msg_find_element(kd->subkeys[idx], "key");
	SMB_ASSERT(el != NULL);
	SMB_ASSERT(el->num_values != 0);
	
	if (name != NULL)
		*name = talloc_strdup(mem_ctx, (char *)el->values[0].data);

	if (classname != NULL)
		*classname = NULL; /* TODO: Store properly */
	
	if (last_mod_time != NULL)
		*last_mod_time = 0; /* TODO: we need to add this to the
						ldb backend properly */

	return WERR_OK;
}

static WERROR ldb_get_value_by_id(TALLOC_CTX *mem_ctx, const struct hive_key *k, int idx, 
								  const char **name, uint32_t *data_type, DATA_BLOB *data)
{
	struct ldb_key_data *kd = talloc_get_type(k, struct ldb_key_data);

	/* Do the search if necessary */
	if (kd->values == NULL) {
		W_ERROR_NOT_OK_RETURN(cache_values(kd));
	}

	if(idx >= kd->value_count) return WERR_NO_MORE_ITEMS;

	reg_ldb_unpack_value(mem_ctx, kd->values[idx], 
						 name, data_type, data);

	return WERR_OK;
}

static WERROR ldb_get_value(TALLOC_CTX *mem_ctx, struct hive_key *k, 
					const char *name, uint32_t *data_type, DATA_BLOB *data)
{
	struct ldb_key_data *kd = talloc_get_type(k, struct ldb_key_data);
	struct ldb_context *c = kd->ldb;
	struct ldb_result *res;
	int ret;
	char *query = talloc_asprintf(mem_ctx, "(value=%s)", name);

	ret = ldb_search(c, kd->dn, LDB_SCOPE_ONELEVEL, query, NULL, &res);

	talloc_free(query);

	if (ret != LDB_SUCCESS) {
		DEBUG(0, ("Error getting values for '%s': %s\n", ldb_dn_get_linearized(kd->dn), ldb_errstring(c)));
		return WERR_FOOBAR;
	}

	if (res->count == 0)
		return WERR_NOT_FOUND;

	reg_ldb_unpack_value(mem_ctx, res->msgs[0], NULL, data_type, data);

	return WERR_OK;
}

static WERROR ldb_open_key(TALLOC_CTX *mem_ctx, const struct hive_key *h, 
						   const char *name, struct hive_key **key)
{
	struct ldb_result *res;
	struct ldb_dn *ldap_path;
	int ret;
	struct ldb_key_data *newkd;
	struct ldb_key_data *kd = talloc_get_type(h, struct ldb_key_data);
	struct ldb_context *c = kd->ldb;

	ldap_path = reg_path_to_ldb(mem_ctx, h, name, NULL);

	ret = ldb_search(c, ldap_path, LDB_SCOPE_BASE, "(key=*)", NULL, &res);

	if (ret != LDB_SUCCESS) {
		DEBUG(3, ("Error opening key '%s': %s\n", 
				  ldb_dn_get_linearized(ldap_path), ldb_errstring(c)));
		return WERR_FOOBAR;
	} else if (res->count == 0) {
		DEBUG(3, ("Key '%s' not found\n", ldb_dn_get_linearized(ldap_path)));
		talloc_free(res);
		return WERR_NOT_FOUND;
	}

	newkd = talloc_zero(mem_ctx, struct ldb_key_data);
	newkd->key.ops = &reg_backend_ldb;
	newkd->ldb = talloc_reference(newkd, kd->ldb);
	newkd->dn = ldb_dn_copy(mem_ctx, res->msgs[0]->dn); 

	*key = (struct hive_key *)newkd;

	talloc_free(res);

	return WERR_OK;
}

WERROR reg_open_ldb_file(TALLOC_CTX *parent_ctx, const char *location, 
			 struct auth_session_info *session_info,
			 struct cli_credentials *credentials,
			 struct hive_key **k)
{
	struct ldb_key_data *kd;
	struct ldb_context *wrap;

	if (location == NULL) 
		return WERR_INVALID_PARAM;

	wrap = ldb_wrap_connect(parent_ctx, global_loadparm, 
				location, session_info, credentials, 0, NULL);

	if (wrap == NULL) {
		DEBUG(1, (__FILE__": unable to connect\n"));
		return WERR_FOOBAR;
	}

	ldb_set_debug_stderr(wrap);

	kd = talloc_zero(parent_ctx, struct ldb_key_data);
	kd->key.ops = &reg_backend_ldb;
	kd->ldb = talloc_reference(kd, wrap);
	talloc_set_destructor (kd, reg_close_ldb_key);
	kd->dn = ldb_dn_new(kd, wrap, "hive=NONE");

	*k = (struct hive_key *)kd;

	return WERR_OK;
}

static WERROR ldb_add_key (TALLOC_CTX *mem_ctx, const struct hive_key *parent, 
						   const char *name, const char *classname,
						   struct security_descriptor *sd, 
						   struct hive_key **newkey)
{
	const struct ldb_key_data *parentkd = (const struct ldb_key_data *)parent;
	struct ldb_message *msg;
	struct ldb_key_data *newkd;
	int ret;

	msg = ldb_msg_new(mem_ctx);

	msg->dn = reg_path_to_ldb(msg, parent, name, NULL);

	ldb_msg_add_string(msg, "key", talloc_strdup(mem_ctx, name));
	if (classname != NULL)
		ldb_msg_add_string(msg, "classname", talloc_strdup(mem_ctx, classname));

	ret = ldb_add(parentkd->ldb, msg);
	if (ret < 0) {
		DEBUG(1, ("ldb_msg_add: %s\n", ldb_errstring(parentkd->ldb)));
		return WERR_FOOBAR;
	} 

	DEBUG(2, ("key added: %s\n", ldb_dn_get_linearized(msg->dn)));

	newkd = talloc_zero(mem_ctx, struct ldb_key_data);
	newkd->ldb = talloc_reference(newkd, parentkd->ldb);
	newkd->key.ops = &reg_backend_ldb;
	newkd->dn = talloc_steal(newkd, msg->dn);

	*newkey = (struct hive_key *)newkd;

	return WERR_OK;
}

static WERROR ldb_del_key (const struct hive_key *key, const char *child)
{
	int ret;
	struct ldb_key_data *parentkd = talloc_get_type(key, struct ldb_key_data);
	struct ldb_dn *childdn;

	childdn = ldb_dn_copy(parentkd->ldb, parentkd->dn);
	ldb_dn_add_child_fmt(childdn, "key=%s", child);

	ret = ldb_delete(parentkd->ldb, childdn);

	talloc_free(childdn);

	if (ret == LDB_ERR_NO_SUCH_OBJECT) {
		return WERR_NOT_FOUND;
	} else if (ret < 0) {
		DEBUG(1, ("ldb_del_key: %s\n", ldb_errstring(parentkd->ldb)));
		return WERR_FOOBAR;
	}

	return WERR_OK;
}

static WERROR ldb_del_value (struct hive_key *key, const char *child)
{
	int ret;
	struct ldb_key_data *kd = talloc_get_type(key, struct ldb_key_data);
	struct ldb_dn *childdn;

	childdn = ldb_dn_copy(kd->ldb, kd->dn);
	ldb_dn_add_child_fmt(childdn, "value=%s", child);

	ret = ldb_delete(kd->ldb, childdn);

	talloc_free(childdn);

	if (ret == LDB_ERR_NO_SUCH_OBJECT) {
		return WERR_NOT_FOUND;
	} else if (ret < 0) {
		DEBUG(1, ("ldb_del_value: %s\n", ldb_errstring(kd->ldb)));
		return WERR_FOOBAR;
	}

	return WERR_OK;
}

static WERROR ldb_set_value(struct hive_key *parent, 
							const char *name, uint32_t type, 
							const DATA_BLOB data)
{
	struct ldb_message *msg;
	struct ldb_key_data *kd = talloc_get_type(parent, struct ldb_key_data);
	int ret;
	TALLOC_CTX *mem_ctx = talloc_init("ldb_set_value");

	msg = reg_ldb_pack_value(kd->ldb, mem_ctx, name, type, data);

	msg->dn = ldb_dn_copy(msg, kd->dn);
	ldb_dn_add_child_fmt(msg->dn, "value=%s", name);

	ret = ldb_add(kd->ldb, msg);
	if (ret < 0) {
		ret = ldb_modify(kd->ldb, msg);
		if (ret < 0) {
			DEBUG(1, ("ldb_msg_add: %s\n", ldb_errstring(kd->ldb)));
			talloc_free(mem_ctx);
			return WERR_FOOBAR;
		}
	}
	
	talloc_free(mem_ctx);
	return WERR_OK;
}

static WERROR ldb_get_key_info(TALLOC_CTX *mem_ctx, 
							   const struct hive_key *key,
							   const char **classname, 
							   uint32_t *num_subkeys,
							   uint32_t *num_values,
							   NTTIME *last_change_time)
{
	struct ldb_key_data *kd = talloc_get_type(key, struct ldb_key_data);

	/* FIXME */
	if (classname != NULL)
		*classname = NULL;

	if (num_subkeys != NULL) {
		W_ERROR_NOT_OK_RETURN(cache_subkeys(kd));
		*num_subkeys = kd->subkey_count;
	}

	if (num_values != NULL) {
		W_ERROR_NOT_OK_RETURN(cache_values(kd));
		*num_values = kd->value_count;
	}

	if (last_change_time != NULL)
		*last_change_time = 0;

	return WERR_OK;
}

static struct hive_operations reg_backend_ldb = {
	.name = "ldb",
	.add_key = ldb_add_key,
	.del_key = ldb_del_key,
	.get_key_by_name = ldb_open_key,
	.enum_value = ldb_get_value_by_id,
	.enum_key = ldb_get_subkey_by_id,
	.set_value = ldb_set_value,
	.get_value_by_name = ldb_get_value,
	.delete_value = ldb_del_value,
	.get_key_info = ldb_get_key_info,
};