/* 
   Unix SMB/CIFS implementation.
   Reading Registry.pol PReg registry files
   
   Copyright (C) Wilco Baan Hofman 2006

   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, write to the Free Software
   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/

#include "includes.h"
#include "lib/registry/registry.h"
#include "system/filesys.h"
#include "pstring.h"

struct preg_data {
	int fd;
};

static WERROR preg_read_utf16(int fd, char *c)
{
	uint16_t v;

	if (read(fd, &v, 2) < 2) {
		return WERR_GENERAL_FAILURE;
	}
	push_codepoint(c, v);
	return WERR_OK;
}

/* FIXME These functions need to be implemented */
static WERROR reg_preg_diff_add_key(void *_data, const char *key_name)
{
	struct preg_data *data = _data;
	return WERR_OK;
}

static WERROR reg_preg_diff_del_key(void *_data, const char *key_name)
{
	struct preg_data *data = _data;
	return WERR_OK;
}

static WERROR reg_preg_diff_set_value(void *_data, const char *key_name, const char *value_name, uint32_t value_type, DATA_BLOB value_data)
{
	struct preg_data *data = _data;
	return WERR_OK;
}

static WERROR reg_preg_diff_del_value(void *_data, const char *key_name, const char *value_name)
{
	struct preg_data *data = _data;
	return WERR_OK;
}

static WERROR reg_preg_diff_del_all_values(void *_data, const char *key_name)
{
	struct preg_data *data = _data;
	return WERR_OK;
}

static WERROR reg_preg_diff_done(void *_data)
{
	struct preg_data *data = _data;

	close(data->fd);
	talloc_free(data);
	return WERR_OK;
}

/**
 * Save registry diff
 */
_PUBLIC_ WERROR reg_preg_diff_save(TALLOC_CTX *ctx, const char *filename, struct reg_diff_callbacks **callbacks, void **callback_data)
{
	struct preg_data *data;
	struct {
		char hdr[4];
		uint32_t version;
	} preg_header;
		

	data = talloc_zero(ctx, struct preg_data);
	*callback_data = data;

	if (filename) {
		data->fd = open(filename, O_CREAT, 0755);
		if (data->fd == -1) {
			DEBUG(0, ("Unable to open %s\n", filename));
			return WERR_BADFILE;
		}
	} else {
		data->fd = STDOUT_FILENO;
	}
	snprintf(preg_header.hdr, 4, "PReg");
	SIVAL(&preg_header, 4, 1);
	write(data->fd, (uint8_t *)&preg_header,8); 

	*callbacks = talloc(ctx, struct reg_diff_callbacks);
	
	(*callbacks)->add_key = reg_preg_diff_add_key;
	(*callbacks)->del_key = reg_preg_diff_del_key;
	(*callbacks)->set_value = reg_preg_diff_set_value;
	(*callbacks)->del_value = reg_preg_diff_del_value;
	(*callbacks)->del_all_values = reg_preg_diff_del_all_values;
	(*callbacks)->done = reg_preg_diff_done;
	
	return WERR_OK;
}
/**
 * Load diff file
 */
_PUBLIC_ WERROR reg_preg_diff_load(int fd, const struct reg_diff_callbacks *callbacks, void *callback_data)
{
	struct {
		char hdr[4];
		uint32_t version;
	} preg_header;
	pstring buf;
	char *buf_ptr = buf;
	TALLOC_CTX *mem_ctx = talloc_init("reg_preg_diff_load");

	
	/* Read first 8 bytes (the header) */
	if (read(fd, &preg_header, 8) != 8) {
		DEBUG(0, ("Could not read PReg file: %s\n",
				strerror(errno)));
		close(fd);
		return WERR_GENERAL_FAILURE;
	}
	if (strncmp(preg_header.hdr, "PReg", 4) != 0) {
		DEBUG(0, ("This file is not a valid preg registry file\n"));
		close(fd);
		return WERR_GENERAL_FAILURE;
	}
	if (preg_header.version > 1) {
		DEBUG(0, ("Warning: file format version is higher than expected.\n"));
	}		

	/* Read the entries */
	while(1) {
		char *key, *value_name;
		uint32_t value_type, length;
		DATA_BLOB data;
		
		if (!W_ERROR_IS_OK(preg_read_utf16(fd, buf_ptr))) {
			break;
		}
		if (*buf_ptr != '[') {
			DEBUG(0, ("Error in PReg file.\n"));
			close(fd);
			return WERR_GENERAL_FAILURE;
		}
	
		/* Get the path */
		buf_ptr = buf;
		while (W_ERROR_IS_OK(preg_read_utf16(fd, buf_ptr)) && *buf_ptr != ';' && buf_ptr-buf < sizeof(buf)) { 
			buf_ptr++;
		}
		key = talloc_asprintf(mem_ctx, "\\%s", buf);
	
		/* Get the name */
		buf_ptr = buf;
		while (W_ERROR_IS_OK(preg_read_utf16(fd, buf_ptr)) && *buf_ptr != ';' && buf_ptr-buf < sizeof(buf)) { 
			buf_ptr++;
		}
		value_name = talloc_strdup(mem_ctx, buf);

		/* Get the type */
		if (read(fd, &value_type, 4) < 4) {
			DEBUG(0, ("Error while reading PReg\n"));
			close(fd);
			return WERR_GENERAL_FAILURE;
		}
		/* Read past delimiter */
		buf_ptr = buf;
		if (!(W_ERROR_IS_OK(preg_read_utf16(fd, buf_ptr)) && *buf_ptr == ';') && buf_ptr-buf < sizeof(buf)) {
			DEBUG(0, ("Error in PReg file.\n"));
			close(fd);
			return WERR_GENERAL_FAILURE;
		}
		/* Get data length */
		if (read(fd, &length, 4) < 4) {
			DEBUG(0, ("Error while reading PReg\n"));
			close(fd);
			return WERR_GENERAL_FAILURE;
		}
		/* Read past delimiter */
		buf_ptr = buf;
		if (!(W_ERROR_IS_OK(preg_read_utf16(fd, buf_ptr)) && *buf_ptr == ';') && buf_ptr-buf < sizeof(buf)) {
			DEBUG(0, ("Error in PReg file.\n"));
			close(fd);
			return WERR_GENERAL_FAILURE;
		}	
		/* Get the data */
		buf_ptr = buf;
		if (length < sizeof(buf) && read(fd, buf_ptr, length) != length) {
			DEBUG(0, ("Error while reading PReg\n"));
			close(fd);
			return WERR_GENERAL_FAILURE;
		}
		data.length = length;
		data.data = talloc_memdup(mem_ctx, buf, length);
		
		/* Check if delimiter is in place (whine if it isn't) */
		buf_ptr = buf;
		if (!(W_ERROR_IS_OK(preg_read_utf16(fd, buf_ptr)) && *buf_ptr == ']') && buf_ptr-buf < sizeof(buf)) {
			DEBUG(0, ("Warning: Missing ']' in PReg file, expected ']', got '%c' 0x%x.\n",*buf_ptr, *buf_ptr));
		}

		if (strcasecmp(value_name, "**DelVals") == 0) {
			callbacks->del_all_values(callback_data, key);
		} else if (strncasecmp(value_name, "**Del.",6) == 0) {
			char *p = value_name+6;
			
			callbacks->del_value(callback_data, key, p);
		} else 	if (strcasecmp(value_name, "**DeleteValues") == 0) {
			char *p, *q;

			p = (char *) data.data;
			
			while ((q = strchr_m(p, ';'))) {
				*q = '\0'; 
				q++;

				callbacks->del_value(callback_data, key, p);

				p = q;
			}
			callbacks->del_value(callback_data, key, p);
		} else if (strcasecmp(value_name, "**DeleteKeys") == 0) {
			char *p, *q, *full_key;

			p = (char *) data.data;
			
			while ((q = strchr_m(p, ';'))) {
				*q = '\0';
				q++;
	
				full_key = talloc_asprintf(mem_ctx, "%s\\%s", key, p);
				callbacks->del_key(callback_data, full_key);
				talloc_free(full_key);

				p = q; 
			}
			full_key = talloc_asprintf(mem_ctx, "%s\\%s", key, p);
			callbacks->del_key(callback_data, full_key);
			talloc_free(full_key);
		} else {
			callbacks->add_key(callback_data, key);
			callbacks->set_value(callback_data, key, value_name, value_type, data);
 		}
		talloc_free(key);
		talloc_free(value_name);
		talloc_free(data.data);
	}
	close(fd);	
	return WERR_OK;
}