/* $Id$
 *
 * Lasso - A free implementation of the Liberty Alliance specifications.
 *
 * Copyright (C) 2004-2007 Entr'ouvert
 * http://lasso.entrouvert.org
 *
 * Authors: See AUTHORS file in top-level directory.
 *
 * 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

/**
 * SECTION:lasso
 * @short_description: Initialization functions
 *
 **/

#include <stdlib.h> /* getenv */
#include <string.h> /* strcmp */
#include <xmlsec/xmlsec.h>
#include <xmlsec/crypto.h>
#include <libxslt/xslt.h>
#include <config.h>
#include "lasso.h"
#include "lasso_config.h"
#include "debug.h"
#include "backward_comp.h"
#include "registry-private.h"
#include "xml/private.h"

/* Set to true, it forces lasso_provider_verify_signature and lasso_query_verify_signature to always
 * return TRUE. */
gboolean lasso_flag_verify_signature = TRUE;
/* Set to true, it activates debugging code for LassoNode freeing */
gboolean lasso_flag_memory_debug = FALSE;
/* set to true, it activates more strict validation of messages */
gboolean lasso_flag_strict_checking = FALSE;
/* set to false, it do not sign messages */
gboolean lasso_flag_add_signature = TRUE;
#ifdef LASSO_WSF_ENABLED
/* set to false, it do not follow stupid id-wsf semantic */
gboolean lasso_flag_follow_id_wsf_stupid_semantic = FALSE;
#endif
static void lasso_flag_parse_environment_variable();
/* do not sign messages */
gboolean lasso_flag_sign_messages = TRUE;

#ifndef LASSO_FLAG_ENV_VAR
#define LASSO_FLAG_ENV_VAR "LASSO_FLAG"
#endif

#if defined _MSC_VER
HINSTANCE g_hModule = NULL;

/**
 * DllMain:
 * @hinstDLL: hnadle to the DLL module
 * @fdwReason: reason value of the DLL call
 * @lpvReserved:
 *
 * Called when the DLL is attached or detached by a program.
 *
 * Return value: %TRUE if everything is OK
 **/
BOOL WINAPI
DllMain(HINSTANCE hinstDLL, DWORD fdwReason, LPVOID lpvReserved)
{
	if (fdwReason == DLL_PROCESS_ATTACH)
	{
		DisableThreadLibraryCalls(hinstDLL);
		g_hModule = hinstDLL;
	}
	return TRUE;
}
#endif

#include "types.c"

/**
 * lasso_init:
 *
 * Initializes Lasso library.
 *
 * Return value: 0 on success; or a negative value otherwise.
 **/
int lasso_init()
{
	int i;

	g_type_init();

	/* Init Lasso classes */
	for (i=0; functions[i]; i++)
		functions[i]();

	/* Init libxml and libxslt libraries */
	xmlInitParser();
	/*LIBXML_TEST_VERSION*/
	/* xmlLoadExtDtdDefaultValue = XML_DETECT_IDS | XML_COMPLETE_ATTRS; */
	/* xmlSubstituteEntitiesDefault(1); */

	/* Init xmlsec library */
	if (xmlSecInit() < 0) {
		message(G_LOG_LEVEL_CRITICAL, "XMLSec initialization failed.");
		return LASSO_ERROR_UNDEFINED;
	}

	/* Load default crypto engine if we are supporting dynamic
	 * loading for xmlsec-crypto libraries. Use the crypto library
	 * name ("openssl", "nss", etc.) to load corresponding
	 * xmlsec-crypto library.
	 */
#ifdef XMLSEC_CRYPTO_DYNAMIC_LOADING
	if (xmlSecCryptoDLLoadLibrary(BAD_CAST XMLSEC_CRYPTO) < 0) {
		message(G_LOG_LEVEL_CRITICAL,
				"Unable to load default xmlsec-crypto library. Make sure"
				"that you have it installed and check shared libraries path"
				"(LD_LIBRARY_PATH) environment variable.");
		return LASSO_ERROR_UNDEFINED;
	}
#endif /* XMLSEC_CRYPTO_DYNAMIC_LOADING */

	/* Init crypto library */
	if (xmlSecCryptoAppInit(NULL) < 0) {
		message(G_LOG_LEVEL_CRITICAL, "Crypto initialization failed.");
		return LASSO_ERROR_UNDEFINED;
	}

	/* Init xmlsec-crypto library */
	if (xmlSecCryptoInit() < 0) {
		message(G_LOG_LEVEL_CRITICAL, "xmlsec-crypto initialization failed.");
		return LASSO_ERROR_UNDEFINED;
	}
	lasso_flag_parse_environment_variable();
	return 0;
}

/**
 * lasso_shutdown:
 *
 * Clean ups Lasso library.
 *
 * Return value: 0 on success; or a negative value otherwise.
 **/
int lasso_shutdown()
{
	/* Shutdown xmlsec-crypto library */
	xmlSecCryptoShutdown();

	/* Shutdown crypto library */
	xmlSecCryptoAppShutdown();

	/* Shutdown xmlsec library */
	xmlSecShutdown();

	/* Shutdown libxslt/libxml */
#ifndef XMLSEC_NO_XSLT
	xsltCleanupGlobals();
#endif /* XMLSEC_NO_XSLT */
	/* Cleanup function for the XML library */
	xmlCleanupParser();

	/* Disallocate default registry */
	lasso_registry_default_shutdown();

	if (lasso_flag_memory_debug == TRUE) {
	/* this is to debug memory for regression tests */
		xmlMemoryDump();
	}
	return 0;
}

/**
 * lasso_check_version:
 * @major: major version numbe
 * @minor: minor version number
 * @subminor: subminor version number
 * @mode: version check mode
 *
 * Checks if the loaded version of Lasso library could be used.
 *
 * Return value: 1 if the loaded lasso library version is OK to use
 *     0 if it is not; or a negative value if an error occurs.
 **/
int
lasso_check_version(int major, int minor, int subminor, LassoCheckVersionMode mode)
{
	if (mode == LASSO_CHECK_VERSION_NUMERIC) {
		if (LASSO_VERSION_MAJOR*10000 + LASSO_VERSION_MINOR*100 + LASSO_VERSION_SUBMINOR <
				major*10000 + minor*100 + subminor)
			return 0;
		return 1;
	}
	/* we always want to have a match for major version number */
	if (major != LASSO_VERSION_MAJOR) {
		g_message("expected major version=%d;real major version=%d",
				LASSO_VERSION_MAJOR, major);
		return 0;
	}

	if (mode == LASSO_CHECK_VERSION_EXACT) {
		if (minor != LASSO_VERSION_MINOR || subminor != LASSO_VERSION_SUBMINOR) {
			g_message("mode=exact;expected minor version=%d;"
					"real minor version=%d;expected subminor version=%d;"
					"real subminor version=%d",
					LASSO_VERSION_MINOR, minor,
					LASSO_VERSION_SUBMINOR, subminor);
			return 0;
		}
	}

	if (mode == LASSO_CHECK_VERSIONABI_COMPATIBLE) {
		if (minor < LASSO_VERSION_MINOR || (minor == LASSO_VERSION_MINOR &&
					subminor < LASSO_VERSION_SUBMINOR)) {
			g_message("mode=abi compatible;expected minor version=%d;"
					"real minor version=%d;expected subminor version=%d;"
					"real subminor version=%d",
					LASSO_VERSION_MINOR, minor,
					LASSO_VERSION_SUBMINOR, subminor);
			return 0;
		}
	}

	if (mode > LASSO_CHECK_VERSION_NUMERIC)
		return LASSO_ERROR_UNDEFINED;

	return 1;
}

/**
 * lasso_set_flag:
 * @flag: a string representing a flag name, prefix with 'no-' to disable it.
 *
 * Set a debugging flag. You can also use the environment variable named by the #LASSO_FLAG_ENV_VAR
 * macro to get the same effect. LASSO_DEBUG must contain flag name separated by spaces, commas,
 * tabulations or colons.
 */
void lasso_set_flag(char *flag) {
	gboolean value = TRUE;

	g_return_if_fail(flag);

	/* Handle negative flags */
	if (flag && strncmp(flag, "no-", 3) == 0) {
		value = FALSE;
		flag += 3;
	}

	do {
		if (g_strcmp0(flag, "verify-signature") == 0) {
			lasso_flag_verify_signature = value;
			continue;
		}
		if (g_strcmp0(flag,"memory-debug") == 0) {
			lasso_flag_memory_debug = value;
			continue;
		}
		if (g_strcmp0(flag,"strict-checking") == 0) {
			lasso_flag_strict_checking = value;
			continue;
		}
		if (g_strcmp0(flag,"add-signature") == 0) {
			lasso_flag_add_signature = value;
			continue;
		}
		if (g_strcmp0(flag, "sign-messages") == 0) {
			lasso_flag_sign_messages = value;
			continue;
		}
#ifdef LASSO_WSF_ENABLED
		if (g_strcmp0(flag, "follow-stupid-id-wsf-semantic") == 0) {
			lasso_flag_follow_id_wsf_stupid_semantic = value;
			continue;
		}
#endif
	} while (FALSE);
}

static void lasso_flag_parse_environment_variable() {
	char *lasso_flag = getenv(LASSO_FLAG_ENV_VAR);
	char *save_ptr;
	char *token;
	const char delim[] = ", \t:";

	if (lasso_flag) {
		token = strtok_r(lasso_flag, delim, &save_ptr);
		do {
			lasso_set_flag(token);
		} while ((token = strtok_r(NULL, delim, &save_ptr)) != NULL);
	}
}