/* 
 * FreeSWITCH Modular Media Switching Software Library / Soft-Switch Application
 * Copyright (C) 2005/2006, Anthony Minessale II <anthmct@yahoo.com>
 *
 * Version: MPL 1.1
 *
 * The contents of this file are subject to the Mozilla Public License Version
 * 1.1 (the "License"); you may not use this file except in compliance with
 * the License. You may obtain a copy of the License at
 * http://www.mozilla.org/MPL/
 *
 * Software distributed under the License is distributed on an "AS IS" basis,
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
 * for the specific language governing rights and limitations under the
 * License.
 *
 * The Original Code is FreeSWITCH Modular Media Switching Software Library / Soft-Switch Application
 *
 * The Initial Developer of the Original Code is
 * Anthony Minessale II <anthmct@yahoo.com>
 * Portions created by the Initial Developer are Copyright (C)
 * the Initial Developer. All Rights Reserved.
 *
 * Contributor(s):
 * 
 * Anthony Minessale II <anthmct@yahoo.com>
 * Ken Rice <krice at suspicious dot org
 *
 * mod_limit.c -- Resource Limit Module
 *
 */

#include <switch.h>
#ifdef SWITCH_HAVE_ODBC
#include <switch_odbc.h>
#endif

SWITCH_MODULE_LOAD_FUNCTION(mod_limit_load);
SWITCH_MODULE_DEFINITION(mod_limit, mod_limit_load, NULL, NULL);

static struct {
	switch_memory_pool_t *pool;
	char hostname[256];
	char *dbname;
	char *odbc_dsn;
	switch_mutex_t *mutex;
#ifdef SWITCH_HAVE_ODBC
	switch_odbc_handle_t *master_odbc;
#else
	void *filler1;
#endif
} globals;

static char limit_sql[] =
	"CREATE TABLE limit_data (\n"
	"   hostname   VARCHAR(255),\n"
	"   realm      VARCHAR(255),\n"
	"   id         VARCHAR(255),\n" 
	"   uuid       VARCHAR(255)\n"
	");\n";


static char db_sql[] =
	"CREATE TABLE db_data (\n"
	"   hostname   VARCHAR(255),\n"
	"   realm      VARCHAR(255),\n"
	"   data_key   VARCHAR(255),\n" 
	"   data       VARCHAR(255)\n"
	");\n";


static char group_sql[] =
	"CREATE TABLE group_data (\n"
	"   hostname   VARCHAR(255),\n"
	"   groupname  VARCHAR(255),\n"
	"   url        VARCHAR(255)\n"
	");\n";



static switch_status_t limit_execute_sql(char *sql, switch_mutex_t *mutex)
{
	switch_core_db_t *db;
	switch_status_t status = SWITCH_STATUS_SUCCESS;

	if (mutex) {
		switch_mutex_lock(mutex);
	}

#ifdef SWITCH_HAVE_ODBC
    if (globals.odbc_dsn) {
		SQLHSTMT stmt;
		if (switch_odbc_handle_exec(globals.master_odbc, sql, &stmt) != SWITCH_ODBC_SUCCESS) {
			char *err_str;
			err_str = switch_odbc_handle_get_error(globals.master_odbc, stmt);
			switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, "ERR: [%s]\n[%s]\n", sql, switch_str_nil(err_str));
			switch_safe_free(err_str);
			status = SWITCH_STATUS_FALSE;
		}
		SQLFreeHandle(SQL_HANDLE_STMT, stmt);
	} else {
#endif
		if (!(db = switch_core_db_open_file(globals.dbname))) {
			switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, "Error Opening DB %s\n", globals.dbname);
			status = SWITCH_STATUS_FALSE;
			goto end;
		}

		status = switch_core_db_persistant_execute(db, sql, 1);
		switch_core_db_close(db);

#ifdef SWITCH_HAVE_ODBC
    }
#endif


 end:
	if (mutex) {
		switch_mutex_unlock(mutex);
	}

    return status;
}


static switch_bool_t limit_execute_sql_callback(switch_mutex_t *mutex,
                                                char *sql,
                                                switch_core_db_callback_func_t callback,
                                                void *pdata)
{
	switch_bool_t ret = SWITCH_FALSE;
	switch_core_db_t *db;
	char *errmsg = NULL;
	
	if (mutex) {
		switch_mutex_lock(mutex);
	}


#ifdef SWITCH_HAVE_ODBC
	if (globals.odbc_dsn) {
		switch_odbc_handle_callback_exec(globals.master_odbc, sql, callback, pdata);
	} else {
#endif
		if (!(db = switch_core_db_open_file(globals.dbname))) {
			switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, "Error Opening DB %s\n", globals.dbname);
			goto end;
		}

		switch_core_db_exec(db, sql, callback, pdata, &errmsg);

		if (errmsg) {
			switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, "SQL ERR: [%s] %s\n", sql, errmsg);
			free(errmsg);
		}

		if (db) {
			switch_core_db_close(db);
		}
#ifdef SWITCH_HAVE_ODBC
	}
#endif

 end:
	if (mutex) {
		switch_mutex_unlock(mutex);
	}

	return ret;

}


static switch_status_t do_config()
{
	char *cf = "limit.conf";
	switch_xml_t cfg, xml, settings, param;
	switch_core_db_t *db;
	switch_status_t status = SWITCH_STATUS_SUCCESS;
	char *odbc_user = NULL;
	char *odbc_pass = NULL;
	char *sql = NULL;

	if (!(xml = switch_xml_open_cfg(cf, &cfg, NULL))) {
		switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, "open of %s failed\n", cf);
		return SWITCH_STATUS_TERM;
	}
    
	if ((settings = switch_xml_child(cfg, "settings"))) {
		for (param = switch_xml_child(settings, "param"); param; param = param->next) {
			char *var = NULL;
			char *val = NULL;
            
			var = (char *) switch_xml_attr_soft(param, "name");
			val = (char *) switch_xml_attr_soft(param, "value");

			if (!strcasecmp(var, "odbc-dsn") && !switch_strlen_zero(val)) {
#ifdef SWITCH_HAVE_ODBC
				globals.odbc_dsn = switch_core_strdup(globals.pool, val);
				if ((odbc_user = strchr(globals.odbc_dsn, ':'))) {
				*odbc_user++ = '\0';
					if ((odbc_pass = strchr(odbc_user, ':'))) {
					*odbc_pass++ = '\0';
					}
				}
#else
				switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, "ODBC IS NOT AVAILABLE!\n");
#endif

			}
		}
	}

	if (switch_strlen_zero(globals.odbc_dsn) || switch_strlen_zero(odbc_user) || switch_strlen_zero(odbc_pass)) {
		globals.dbname = "call_limit";
	}
    

#ifdef SWITCH_HAVE_ODBC
	if (globals.odbc_dsn) {
		if (!(globals.master_odbc = switch_odbc_handle_new(globals.odbc_dsn, odbc_user, odbc_pass))) {
			switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_CRIT, "Cannot Open ODBC Database!\n");
			status = SWITCH_STATUS_FALSE;
			goto done;
		}
		if (switch_odbc_handle_connect(globals.master_odbc) != SWITCH_ODBC_SUCCESS) {
			switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_CRIT, "Cannot Open ODBC Database!\n");
			status = SWITCH_STATUS_FALSE;
			goto done;
		}
        
		switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_INFO, "Connected ODBC DSN: %s\n", globals.odbc_dsn);
		if (switch_odbc_handle_exec(globals.master_odbc, "select count(*) from limit_data", NULL) != SWITCH_STATUS_SUCCESS) {
			if (switch_odbc_handle_exec(globals.master_odbc, limit_sql, NULL) != SWITCH_STATUS_SUCCESS) {
			switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_CRIT, "Cannot Create SQL Database!\n");
			}
		}
		if (switch_odbc_handle_exec(globals.master_odbc, "select count(*) from db_data", NULL) != SWITCH_STATUS_SUCCESS) {
			if (switch_odbc_handle_exec(globals.master_odbc, db_sql, NULL) != SWITCH_STATUS_SUCCESS) {
				switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_CRIT, "Cannot Create SQL Database!\n");
			}
		}
		if (switch_odbc_handle_exec(globals.master_odbc, "select count(*) from group_data", NULL) != SWITCH_STATUS_SUCCESS) {
			if (switch_odbc_handle_exec(globals.master_odbc, group_sql, NULL) != SWITCH_STATUS_SUCCESS) {
				switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_CRIT, "Cannot Create SQL Database!\n");
			}
		}
	} else {
#endif
		if ((db = switch_core_db_open_file(globals.dbname))) {
			switch_core_db_test_reactive(db, "select * from limit_data", NULL, limit_sql);
			switch_core_db_test_reactive(db, "select * from db_data", NULL, db_sql);
			switch_core_db_test_reactive(db, "select * from group_data", NULL, group_sql);
		} else {
			switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_CRIT, "Cannot Open SQL Database!\n");
			status = SWITCH_STATUS_FALSE;
			goto done;
		}
		switch_core_db_close(db);
#ifdef SWITCH_HAVE_ODBC
	}           
#endif

 done:

	sql = switch_mprintf("delete from limit_data where hostname='%q';", globals.hostname);
	limit_execute_sql(sql, globals.mutex);
	switch_safe_free(sql);

	switch_xml_free(xml);

	return status;

}

static switch_status_t hanguphook(switch_core_session_t *session)
{
	switch_channel_t *channel = switch_core_session_get_channel(session);
	switch_channel_state_t state = switch_channel_get_state(channel);
	const char *realm = NULL;
	const char *id = NULL;
	char *sql = NULL;

	if (state == CS_HANGUP || state == CS_ROUTING) {
		id = switch_channel_get_variable(channel, "limit_id");
		realm = switch_channel_get_variable(channel, "limit_realm");
		sql = switch_mprintf("delete from limit_data where uuid='%q' and hostname='%q' and realm='%q'and id='%q';", 
                             switch_core_session_get_uuid(session), globals.hostname, realm, id);
		limit_execute_sql(sql, globals.mutex);
		switch_safe_free(sql);
		switch_core_event_hook_remove_state_change(session, hanguphook);
	}
	return SWITCH_STATUS_SUCCESS;
}

struct callback {
	char *buf;
	size_t len;
	int matches;
};
typedef struct callback callback_t;
static int sql2str_callback(void *pArg, int argc, char **argv, char **columnNames)
{
	callback_t *cbt = (callback_t *) pArg;

	switch_copy_string(cbt->buf, argv[0], cbt->len);
	cbt->matches++;
	return 0;
}


static int group_callback(void *pArg, int argc, char **argv, char **columnNames)
{
	callback_t *cbt = (callback_t *) pArg;
	switch_snprintf(cbt->buf + strlen(cbt->buf), cbt->len - strlen(cbt->buf), "%s%c", argv[0], *argv[1]);
	cbt->matches++;
	return 0;
}


SWITCH_STANDARD_API(db_api_function)
{
	int argc = 0;
	char *argv[4] = { 0 };
	char *mydata = NULL;
	char *sql;

	switch_mutex_lock(globals.mutex);

	if (!switch_strlen_zero(cmd)) {
		mydata = strdup(cmd);
		argc = switch_separate_string(mydata, '/', argv, (sizeof(argv) / sizeof(argv[0])));
	}

	if (argc < 1 || !argv[0]) {
		goto error;
	}

	if (!strcasecmp(argv[0], "insert")) {
		if (argc < 4) {
			goto error;
		}
		sql = switch_mprintf("delete from db_data where realm='%q' and data_key='%q'", argv[1], argv[2]);
		assert(sql);
		limit_execute_sql(sql, NULL);
		switch_safe_free(sql);    
		sql = switch_mprintf("insert into db_data (hostname, realm, data_key, data) values('%q','%q','%q','%q');", globals.hostname, argv[1], argv[2], argv[3]);
		assert(sql);
		limit_execute_sql(sql, NULL);
		switch_safe_free(sql);
		stream->write_function(stream, "+OK");
		goto done;
	} else if (!strcasecmp(argv[0], "delete")) {
		if (argc < 2) {
			goto error;
		}
		sql = switch_mprintf("delete from db_data where realm='%q' and data_key='%q'", argv[1], argv[2]);
		assert(sql);
		limit_execute_sql(sql, NULL);
		switch_safe_free(sql);    
		stream->write_function(stream, "+OK");
		goto done;
	} else if (!strcasecmp(argv[0], "select")) {
		char buf[256] = "";
		callback_t cbt = { 0 };
		if (argc < 3) {
			goto error;
		}
		cbt.buf = buf;
		cbt.len = sizeof(buf);
		sql = switch_mprintf("select data from db_data where realm='%q' and data_key='%q'", argv[1], argv[2]);
		limit_execute_sql_callback(NULL, sql, sql2str_callback, &cbt);
		stream->write_function(stream, "%s", buf);
		goto done;
	} 


 error:
	stream->write_function(stream, "!err!");
    
 done:

	switch_mutex_unlock(globals.mutex);
	switch_safe_free(mydata);
	return SWITCH_STATUS_SUCCESS;
    
}


#define DB_USAGE "[insert|delete]/<realm>/<key>/<val>"
#define DB_DESC "save data"

SWITCH_STANDARD_APP(db_function)
{
	int argc = 0;
	char *argv[4] = { 0 };
	char *mydata = NULL;
	char *sql = NULL;

	if (!switch_strlen_zero(data)) {
		mydata = switch_core_session_strdup(session, data);
		argc = switch_separate_string(mydata, '/', argv, (sizeof(argv) / sizeof(argv[0])));
	}

	if (argc < 4 || !argv[0]) {
		goto error;
	}

	if (!strcasecmp(argv[0], "insert")) {
		sql = switch_mprintf("delete from db_data where realm='%q' and data_key='%q'", argv[1], argv[2]);
		switch_assert(sql);
		limit_execute_sql(sql, globals.mutex);
		switch_safe_free(sql);
        
		sql = switch_mprintf("insert into db_data (hostname, realm, data_key, data) values('%q','%q','%q','%q');", globals.hostname, argv[1], argv[2], argv[3]);
	} else if (!strcasecmp(argv[0], "delete")) {
		sql = switch_mprintf("delete from db_data where realm='%q' and data_key='%q'", argv[1], argv[2]);
	}

	switch_assert(sql);
	limit_execute_sql(sql, globals.mutex);
	switch_safe_free(sql);
	return;

error:
	switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_WARNING, "USAGE: db %s\n", DB_USAGE);
}



SWITCH_STANDARD_API(group_api_function)
{
	int argc = 0;
	char *argv[4] = { 0 };
	char *mydata = NULL;
	char *sql;

	switch_mutex_lock(globals.mutex);

	if (!switch_strlen_zero(cmd)) {
		mydata = strdup(cmd);
		argc = switch_separate_string(mydata, ':', argv, (sizeof(argv) / sizeof(argv[0])));
	}

	if (argc < 2 || !argv[0]) {
		goto error;
	}

	if (!strcasecmp(argv[0], "insert")) {
		if (argc < 3) {
			goto error;
		}
		sql = switch_mprintf("delete from group_data where groupname='%q' and url='%q';", argv[1], argv[2]);
		assert(sql);

		limit_execute_sql(sql, NULL);
		switch_safe_free(sql);
		sql = switch_mprintf("insert into group_data (hostname, groupname, url) values('%q','%q','%q');", globals.hostname, argv[1], argv[2]);
		assert(sql);
		limit_execute_sql(sql, NULL);
		switch_safe_free(sql);
		stream->write_function(stream, "+OK");
		goto done;
	} else if (!strcasecmp(argv[0], "delete")) {
		if (argc < 3) {
			goto error;
		}
		if (!strcmp(argv[2], "*")) {
			sql = switch_mprintf("delete from group_data where groupname='%q';", argv[1]);
		} else {
			sql = switch_mprintf("delete from group_data where groupname='%q' and url='%q';", argv[1], argv[2]);
		}
		assert(sql);
		limit_execute_sql(sql, NULL);
		switch_safe_free(sql);
		stream->write_function(stream, "+OK");
		goto done;
	} else if (!strcasecmp(argv[0], "call")) {
		char buf[4096] = "";
		char *how = ",";
		callback_t cbt = { 0 };
		cbt.buf = buf;
		cbt.len = sizeof(buf);
        
		if (argc > 2) {
			if (!strcasecmp(argv[2], "order")) {
				how = "|";
			}
		}

		sql = switch_mprintf("select url,'%q' from group_data where groupname='%q'", how, argv[1]);
		assert(sql);

		limit_execute_sql_callback(NULL, sql, group_callback, &cbt);
		*(buf + (strlen(buf) - 1)) = '\0';
		stream->write_function(stream, "%s", buf);
		goto done;
	}

 error:
	stream->write_function(stream, "!err!");
    
 done:

	switch_mutex_unlock(globals.mutex);
	switch_safe_free(mydata);
	return SWITCH_STATUS_SUCCESS;
    
}

#define GROUP_USAGE "[insert|delete]:<group name>:<val>"
#define GROUP_DESC "save data"

SWITCH_STANDARD_APP(group_function)
{
	int argc = 0;
	char *argv[3] = { 0 };
	char *mydata = NULL;
	char *sql;

	if (!switch_strlen_zero(data)) {
		mydata = switch_core_session_strdup(session, data);
		argc = switch_separate_string(mydata, ':', argv, (sizeof(argv) / sizeof(argv[0])));
	}

	if (argc < 3 || !argv[0]) {
		switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_WARNING, "USAGE: group %s\n", DB_USAGE);
		return;
	}

	if (!strcasecmp(argv[0], "insert")) {
		sql = switch_mprintf("insert into group_data (hostname, groupname, url) values('%q','%q','%q');", globals.hostname, argv[1], argv[2]);
		assert(sql);
		limit_execute_sql(sql, globals.mutex);
		switch_safe_free(sql);
	} else if (!strcasecmp(argv[0], "delete")) {
		sql = switch_mprintf("delete from group_data where groupname='%q' and url='%q';", argv[1], argv[2]);
		assert(sql);
		limit_execute_sql(sql, globals.mutex);
		switch_safe_free(sql);
	}

}

#define LIMIT_USAGE "<realm> <id> <max> [transfer_destination_number]"
#define LIMIT_DESC "limit access to an extension"
static char *limit_def_xfer_exten="limit_exceeded";

SWITCH_STANDARD_APP(limit_function)
{
	int argc = 0;
	char *argv[6] = { 0 };
	char *mydata = NULL;
	char *sql = NULL;
	char *realm = NULL;
	char *id = NULL;
	char *xfer_exten = NULL;
	int max = 0, got = 0;
	char buf[80] = "";
	callback_t cbt = { 0 };
	switch_channel_t *channel = switch_core_session_get_channel(session);

	if (!switch_strlen_zero(data)) {
		mydata = switch_core_session_strdup(session, data);
		argc = switch_separate_string(mydata, ' ', argv, (sizeof(argv) / sizeof(argv[0])));
	}

	if (argc < 3) {
		switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_WARNING, "USAGE: limit %s\n", LIMIT_USAGE);
		return;
	}

	switch_mutex_lock(globals.mutex);

	realm = argv[0];
	id = argv[1];
	max = atoi(argv[2]);

	if (argc == 4) {
		xfer_exten = argv[3];
	} else {
		xfer_exten = limit_def_xfer_exten;
	}

	if (max < 0) {
		max = 0;
	}
    
	switch_channel_set_variable(channel, "limit_realm", realm);
	switch_channel_set_variable(channel, "limit_id", id);
	switch_channel_set_variable(channel, "limit_max", argv[2]);

	cbt.buf = buf;
	cbt.len = sizeof(buf);
	sql = switch_mprintf("select count(hostname) from limit_data where realm='%q' and id like '%q'", realm, id);
	limit_execute_sql_callback(NULL, sql, sql2str_callback, &cbt);
	got = atoi(buf);

	if (got + 1 > max) {
		switch_ivr_session_transfer(session, xfer_exten, NULL, NULL);
		goto done;
	}

	switch_core_event_hook_add_state_change(session, hanguphook);
	sql = switch_mprintf("insert into limit_data (hostname, realm, id, uuid) values('%q','%q','%q','%q');", globals.hostname, realm, id, switch_core_session_get_uuid(session));
	limit_execute_sql(sql, NULL);
	switch_safe_free(sql);

done:
	switch_mutex_unlock(globals.mutex);
}


SWITCH_MODULE_LOAD_FUNCTION(mod_limit_load)
{
	switch_status_t status;
	switch_application_interface_t *app_interface;
	switch_api_interface_t *commands_api_interface;

	memset(&globals, 0, sizeof(&globals));
	gethostname(globals.hostname, sizeof(globals.hostname));
	globals.pool = pool;

	if ((status = do_config() != SWITCH_STATUS_SUCCESS)) {
		return status;
	}

	switch_mutex_init(&globals.mutex, SWITCH_MUTEX_NESTED, globals.pool);
    
	/* connect my internal structure to the blank pointer passed to me */
	*module_interface = switch_loadable_module_create_module_interface(pool, modname);

	SWITCH_ADD_APP(app_interface, "limit", "Limit", LIMIT_DESC, limit_function, LIMIT_USAGE, SAF_SUPPORT_NOMEDIA);
	SWITCH_ADD_APP(app_interface, "db", "Insert to the db", DB_DESC, db_function, DB_USAGE, SAF_SUPPORT_NOMEDIA);
	SWITCH_ADD_APP(app_interface, "group", "Manage a group", GROUP_DESC, group_function, GROUP_USAGE, SAF_SUPPORT_NOMEDIA);

	SWITCH_ADD_API(commands_api_interface, "db", "db get/set", db_api_function, "[insert|delete|select]/<realm>/<key>/<value>");
	SWITCH_ADD_API(commands_api_interface, "group", "group [insert|delete|call]", group_api_function, "[insert|delete|call]:<group name>:<url>");

	/* indicate that the module should continue to be loaded */
	return SWITCH_STATUS_SUCCESS;
}



/* For Emacs:
 * Local Variables:
 * mode:c
 * indent-tabs-mode:t
 * tab-width:4
 * c-basic-offset:4
 * End:
 * For VIM:
 * vim:set softtabstop=4 shiftwidth=4 tabstop=4 expandtab:
 */
