/*
 * FreeSWITCH Modular Media Switching Software Library / Soft-Switch Application
 * Copyright (C) 2005-2014, Anthony Minessale II <anthm@freeswitch.org>
 *
 * 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 <anthm@freeswitch.org>
 * Portions created by the Initial Developer are Copyright (C)
 * the Initial Developer. All Rights Reserved.
 *
 * Contributor(s):
 *
 * Anthony Minessale II <anthm@freeswitch.org>
 * Michael Jerris <mike@jerris.com>
 * Paul D. Tinsley <pdt at jackhammer.org>
 * Christopher M. Rienzo <chris@rienzo.com>
 * Luke Dashjr <luke@openmethods.com> (OpenMethods, LLC)
 *
 *
 * switch_core_asr.c -- Main Core Library (Speech Detection Interface)
 *
 */

#include <switch.h>
#include "private/switch_core_pvt.h"

SWITCH_DECLARE(switch_status_t) switch_core_asr_open(switch_asr_handle_t *ah,
													 const char *module_name,
													 const char *codec, int rate, const char *dest, switch_asr_flag_t *flags, switch_memory_pool_t *pool)
{
	switch_status_t status;
	char *module_name_dup = NULL;
	char *param = NULL;
	int free_pool = 0;

	if (!pool) {
		if ((status = switch_core_new_memory_pool(&pool)) != SWITCH_STATUS_SUCCESS) {
			return status;
		}
		free_pool = 1;
	}

	if (strchr(module_name, ':')) {
		module_name_dup = switch_core_strdup(pool, module_name);
		if ((param = strchr(module_name_dup, ':'))) {
			*param++ = '\0';
			module_name = module_name_dup;
		}
	}

	switch_assert(ah != NULL);

	if ((ah->asr_interface = switch_loadable_module_get_asr_interface(module_name)) == 0) {
		switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, "Invalid ASR module [%s]!\n", module_name);
		if (free_pool) {
			switch_core_destroy_memory_pool(&pool);
		}
		return SWITCH_STATUS_GENERR;
	}

	ah->flags = *flags;

	ah->memory_pool = pool;
	if (free_pool) {
		switch_set_flag(ah, SWITCH_ASR_FLAG_FREE_POOL);
	}
	if (param) {
		ah->param = param;
	}
	ah->rate = rate;
	ah->name = switch_core_strdup(ah->memory_pool, module_name);
	ah->samplerate = rate;
	ah->native_rate = rate;

	status = ah->asr_interface->asr_open(ah, codec, rate, dest, flags);

	if (status != SWITCH_STATUS_SUCCESS) {
		if (switch_test_flag(ah, SWITCH_ASR_FLAG_FREE_POOL)) {
			switch_core_destroy_memory_pool(&ah->memory_pool);
		}
		UNPROTECT_INTERFACE(ah->asr_interface);
	}

	return status;

}

SWITCH_DECLARE(switch_status_t) switch_core_asr_load_grammar(switch_asr_handle_t *ah, const char *grammar, const char *name)
{
	switch_status_t status = SWITCH_STATUS_SUCCESS;
	char *param_string = NULL;
	char *data = NULL;
	char *lgrammar = NULL;

	switch_assert(ah != NULL);

	if (zstr(grammar)) {
		status = SWITCH_STATUS_FALSE;
		goto done;
	}

	/* Set ASR parameters from params in the grammar string
	 * Params are defined as follows {name1=val1,name2=val2,name3=val3}grammar text
	 */
	lgrammar = strdup(grammar);
	data = lgrammar;

	/* strip leading spaces */
	while (data && *data == ' ') {
		data++;
	}
	if (zstr(data)) {
		status = SWITCH_STATUS_FALSE;
		goto done;
	}

	/* extract params */
	if (*data == '{') {
		param_string = data + 1;
		data = switch_find_end_paren(data, '{', '}');
		if (zstr(data)) {
			status = SWITCH_STATUS_FALSE;
			goto done;
		} else {
			*data = '\0';
			data++;
		}
	}

	/* set ASR params */
	if (!zstr(param_string)) {
		char *param[256] = { 0 };
		int i;
		int argc = switch_separate_string(param_string, ',', param, (sizeof(param) / sizeof(param[0])));
		for (i = 0; i < argc && param[i]; ++i) {
			char *param_pair[2] = { 0 };
			if (switch_separate_string(param[i], '=', param_pair, (sizeof(param_pair) / sizeof(param_pair[0]))) == 2) {
				switch_core_asr_text_param(ah, param_pair[0], param_pair[1]);
			}
		}
	}

	status = ah->asr_interface->asr_load_grammar(ah, data, name);

  done:

	switch_safe_free(lgrammar);
	return status;
}

SWITCH_DECLARE(switch_status_t) switch_core_asr_unload_grammar(switch_asr_handle_t *ah, const char *name)
{
	switch_status_t status;

	switch_assert(ah != NULL);
	status = ah->asr_interface->asr_unload_grammar(ah, name);

	return status;
}

SWITCH_DECLARE(switch_status_t) switch_core_asr_enable_grammar(switch_asr_handle_t *ah, const char *name)
{
	switch_status_t status = SWITCH_STATUS_FALSE;

	switch_assert(ah != NULL);

	if (ah->asr_interface->asr_enable_grammar) {
		status = ah->asr_interface->asr_enable_grammar(ah, name);
	}

	return status;
}

SWITCH_DECLARE(switch_status_t) switch_core_asr_disable_grammar(switch_asr_handle_t *ah, const char *name)
{
	switch_status_t status = SWITCH_STATUS_FALSE;

	switch_assert(ah != NULL);

	if (ah->asr_interface->asr_disable_grammar) {
		status = ah->asr_interface->asr_disable_grammar(ah, name);
	}

	return status;
}

SWITCH_DECLARE(switch_status_t) switch_core_asr_disable_all_grammars(switch_asr_handle_t *ah)
{
	switch_status_t status = SWITCH_STATUS_FALSE;

	switch_assert(ah != NULL);

	if (ah->asr_interface->asr_disable_all_grammars) {
		status = ah->asr_interface->asr_disable_all_grammars(ah);
	}

	return status;
}

SWITCH_DECLARE(switch_status_t) switch_core_asr_pause(switch_asr_handle_t *ah)
{
	switch_assert(ah != NULL);

	return ah->asr_interface->asr_pause(ah);
}

SWITCH_DECLARE(switch_status_t) switch_core_asr_resume(switch_asr_handle_t *ah)
{
	switch_assert(ah != NULL);

	return ah->asr_interface->asr_resume(ah);
}

SWITCH_DECLARE(switch_status_t) switch_core_asr_close(switch_asr_handle_t *ah, switch_asr_flag_t *flags)
{
	switch_status_t status;

	switch_assert(ah != NULL);

	status = ah->asr_interface->asr_close(ah, flags);
	switch_set_flag(ah, SWITCH_ASR_FLAG_CLOSED);

	switch_safe_free(ah->dbuf);
	switch_resample_destroy(&ah->resampler);

	UNPROTECT_INTERFACE(ah->asr_interface);

	if (switch_test_flag(ah, SWITCH_ASR_FLAG_FREE_POOL)) {
		switch_core_destroy_memory_pool(&ah->memory_pool);
	}

	return status;
}

SWITCH_DECLARE(switch_status_t) switch_core_asr_feed(switch_asr_handle_t *ah, void *data, unsigned int len, switch_asr_flag_t *flags)
{
	switch_size_t orig_len = len;
	switch_assert(ah != NULL);

	if (ah->native_rate && ah->samplerate && ah->native_rate != ah->samplerate) {
		if (!ah->resampler) {
			if (switch_resample_create(&ah->resampler,
									   ah->samplerate, ah->native_rate, (uint32_t) orig_len, SWITCH_RESAMPLE_QUALITY, 1) != SWITCH_STATUS_SUCCESS) {
				switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_CRIT, "Unable to create resampler!\n");
				return SWITCH_STATUS_GENERR;
			}
		}

		switch_resample_process(ah->resampler, data, len / 2);
		if (ah->resampler->to_len * 2 > orig_len) {
			if (ah->dbuflen < ah->resampler->to_len * 2) {
				void *mem;
				ah->dbuflen = ah->resampler->to_len * 2;
				mem = realloc(ah->dbuf, ah->dbuflen);
				switch_assert(mem);
				ah->dbuf = mem;
			}
			switch_assert(ah->resampler->to_len * 2 <= ah->dbuflen);
			memcpy(ah->dbuf, ah->resampler->to, ah->resampler->to_len * 2);
			data = ah->dbuf;
		} else {
			memcpy(data, ah->resampler->to, ah->resampler->to_len * 2);
		}

		len = ah->resampler->to_len * 2;
	}

	return ah->asr_interface->asr_feed(ah, data, len, flags);
}

SWITCH_DECLARE(switch_status_t) switch_core_asr_feed_dtmf(switch_asr_handle_t *ah, const switch_dtmf_t *dtmf, switch_asr_flag_t *flags)
{
	switch_status_t status = SWITCH_STATUS_SUCCESS;

	switch_assert(ah != NULL);

	if (ah->asr_interface->asr_feed_dtmf) {
		status = ah->asr_interface->asr_feed_dtmf(ah, dtmf, flags);
	}

	return status;
}

SWITCH_DECLARE(switch_status_t) switch_core_asr_check_results(switch_asr_handle_t *ah, switch_asr_flag_t *flags)
{
	switch_assert(ah != NULL);

	return ah->asr_interface->asr_check_results(ah, flags);
}

SWITCH_DECLARE(switch_status_t) switch_core_asr_get_results(switch_asr_handle_t *ah, char **xmlstr, switch_asr_flag_t *flags)
{
	switch_assert(ah != NULL);

	return ah->asr_interface->asr_get_results(ah, xmlstr, flags);
}

SWITCH_DECLARE(switch_status_t) switch_core_asr_get_result_headers(switch_asr_handle_t *ah, switch_event_t **headers, switch_asr_flag_t *flags)
{
	switch_assert(ah != NULL);

	if (ah->asr_interface->asr_get_result_headers) {
		return ah->asr_interface->asr_get_result_headers(ah, headers, flags);
	} else {
		/* Since this is not always implemented, return success if the function can't be called */
		return SWITCH_STATUS_SUCCESS;
	}
}

SWITCH_DECLARE(switch_status_t) switch_core_asr_start_input_timers(switch_asr_handle_t *ah)
{
	switch_status_t status = SWITCH_STATUS_SUCCESS;

	switch_assert(ah != NULL);

	if (ah->asr_interface->asr_start_input_timers) {
		status = ah->asr_interface->asr_start_input_timers(ah);
	}

	return status;
}

SWITCH_DECLARE(void) switch_core_asr_text_param(switch_asr_handle_t *ah, char *param, const char *val)
{
	switch_assert(ah != NULL);

	if (ah->asr_interface->asr_text_param) {
		ah->asr_interface->asr_text_param(ah, param, val);
	}
}

SWITCH_DECLARE(void) switch_core_asr_numeric_param(switch_asr_handle_t *ah, char *param, int val)
{
	switch_assert(ah != NULL);

	if (ah->asr_interface->asr_numeric_param) {
		ah->asr_interface->asr_numeric_param(ah, param, val);
	}
}

SWITCH_DECLARE(void) switch_core_asr_float_param(switch_asr_handle_t *ah, char *param, double val)
{
	switch_assert(ah != NULL);

	if (ah->asr_interface->asr_float_param) {
		ah->asr_interface->asr_float_param(ah, param, val);
	}
}

/* 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 noet:
 */
