/** Node type: IEC 61850-9-2 (Sampled Values)
 *
 * @author Steffen Vogel <stvogel@eonerc.rwth-aachen.de>
 * @copyright 2014-2020, Institute for Automation of Complex Power Systems, EONERC
 * @license GNU General Public License (version 3)
 *
 * VILLASnode
 *
 * 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
 * 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/>.
 *********************************************************************************/

#if CONFIG_IEC61850_SAMPLED_VALUES_SUPPORT == 1

#include <cstring>
#include <pthread.h>
#include <unistd.h>

#include <villas/nodes/iec61850_sv.hpp>

#define CONFIG_SV_DEFAULT_APPID 0x4000
#define CONFIG_SV_DEFAULT_DST_ADDRESS CONFIG_GOOSE_DEFAULT_DST_ADDRESS
#define CONFIG_SV_DEFAULT_PRIORITY 4
#define CONFIG_SV_DEFAULT_VLAN_ID 0

using namespace villas;
using namespace villas::utils;
using namespace villas::node;

static void iec61850_sv_listener(SVSubscriber subscriber, void *ctx, SVSubscriber_ASDU asdu)
{
	struct vnode *n = (struct vnode *) ctx;
	struct iec61850_sv *i = (struct iec61850_sv *) n->_vd;
	struct sample *smp;

	const char* svid = SVSubscriber_ASDU_getSvId(asdu);
	int smpcnt       = SVSubscriber_ASDU_getSmpCnt(asdu);
	int confrev      = SVSubscriber_ASDU_getConfRev(asdu);
	int sz;

	n->logger->debug("Received SV: svid={}, smpcnt={}, confrev={}", svid, smpcnt, confrev);

	sz = SVSubscriber_ASDU_getDataSize(asdu);
	if (sz < i->in.total_size) {
		n->node->warn("Received truncated ASDU: size={}, expected={}", SVSubscriber_ASDU_getDataSize(asdu), i->in.total_size);
		return;
	}

	/* Access to the data requires a priori knowledge of the data set.
	 * For this example we assume a data set consisting of FLOAT32 values.
	 * A FLOAT32 value is encoded as 4 bytes. You can find the first FLOAT32
	 * value at byte position 0, the second value at byte position 4, the third
	 * value at byte position 8, and so on.
	 *
	 * To prevent damages due configuration, please check the length of the
	 * data block of the SV message before accessing the data.
	 */

	smp = sample_alloc(&i->in.pool);
	if (!smp) {
		n->logger->warn("Pool underrun in subscriber");
		return;
	}

	smp->sequence = smpcnt;
	smp->flags = (int) SampleFlags::HAS_SEQUENCE | (int) SampleFlags::HAS_DATA;
	smp->length = 0;
	smp->signals = &n->in.signals;

	if (SVSubscriber_ASDU_hasRefrTm(asdu)) {
		uint64_t refrtm = SVSubscriber_ASDU_getRefrTmAsMs(asdu);

		smp->ts.origin.tv_sec = refrtm / 1000;
		smp->ts.origin.tv_nsec = (refrtm % 1000) * 1000000;
		smp->flags |= (int) SampleFlags::HAS_TS_ORIGIN;
	}

	unsigned offset = 0;
	for (size_t j = 0; j < vlist_length(&i->in.signals); j++) {
		struct iec61850_type_descriptor *td = (struct iec61850_type_descriptor *) vlist_at(&i->in.signals, j);
		struct signal *sig = (struct signal *) vlist_at_safe(smp->signals, j);
		if (!sig)
			continue;

		switch (td->iec_type) {
			case IEC61850Type::INT8:
				smp->data[j].i = SVSubscriber_ASDU_getINT8(asdu,    offset);
				break;

			case IEC61850Type::INT16:
				smp->data[j].i = SVSubscriber_ASDU_getINT16(asdu,   offset);
				break;

			case IEC61850Type::INT32:
				smp->data[j].i = SVSubscriber_ASDU_getINT32(asdu,   offset);
				break;

			case IEC61850Type::INT8U:
				smp->data[j].i = SVSubscriber_ASDU_getINT8U(asdu,   offset);
				break;

			case IEC61850Type::INT16U:
				smp->data[j].i = SVSubscriber_ASDU_getINT16U(asdu,  offset);
				break;

			case IEC61850Type::INT32U:
				smp->data[j].i = SVSubscriber_ASDU_getINT32U(asdu,  offset);
				break;

			case IEC61850Type::FLOAT32:
				smp->data[j].f = SVSubscriber_ASDU_getFLOAT32(asdu, offset);
				break;

			case IEC61850Type::FLOAT64:
				smp->data[j].f = SVSubscriber_ASDU_getFLOAT64(asdu, offset);
				break;

			default: { }
		}

		offset += td->size;

		smp->length++;
	}

	int pushed __attribute__((unused));
	pushed = queue_signalled_push(&i->in.queue, smp);
}

int iec61850_sv_parse(struct vnode *n, json_t *json)
{
	int ret;
	struct iec61850_sv *i = (struct iec61850_sv *) n->_vd;

	const char *dst_address = nullptr;
	const char *interface = nullptr;
	const char *svid = nullptr;
	const char *smpmod = nullptr;

	json_t *json_in = nullptr;
	json_t *json_out = nullptr;
	json_t *json_signals = nullptr;
	json_error_t err;

	/* Default values */
	i->out.enabled = false;
	i->in.enabled = false;
	i->out.smpmod = -1; /* do not set smpmod */
	i->out.smprate = -1; /* do not set smpmod */
	i->out.confrev = 1;
	i->out.vlan_priority = CONFIG_SV_DEFAULT_PRIORITY;
	i->out.vlan_id = CONFIG_SV_DEFAULT_VLAN_ID;

	i->app_id = CONFIG_SV_DEFAULT_APPID;

	uint8_t tmp[] = CONFIG_SV_DEFAULT_DST_ADDRESS;
	memcpy(i->dst_address.ether_addr_octet, tmp, sizeof(i->dst_address.ether_addr_octet));

	ret = json_unpack_ex(json, &err, 0, "{ s?: o, s?: o, s: s, s?: i, s?: s }",
		"out", &json_out,
		"in", &json_in,
		"interface", &interface,
		"app_id", &i->app_id,
		"dst_address", &dst_address
	);
	if (ret)
		throw ConfigError(json, err, "node-config-node-iec61850-sv");

	if (interface)
		i->interface = strdup(interface);

	if (dst_address) {
#ifdef __APPLE__
		struct ether_addr *ether = ether_aton(dst_address);
		memcpy(&i->dst_address, ether, sizeof(struct ether_addr));
#else
		ether_aton_r(dst_address, &i->dst_address);
#endif
	}

	if (json_out) {
		i->out.enabled = true;

		ret = json_unpack_ex(json_out, &err, 0, "{ s: o, s: s, s?: i, s?: s, s?: i, s?: i, s?: i }",
			"signals", &json_signals,
			"svid", &svid,
			"confrev", &i->out.confrev,
			"smpmod", &smpmod,
			"smprate", &i->out.smprate,
			"vlan_id", &i->out.vlan_id,
			"vlan_priority", &i->out.vlan_priority
		);
		if (ret)
			throw ConfigError(json_out, err, "node-config-node-iec61850-sv-out");

		if (smpmod) {
			if      (!strcmp(smpmod, "per_nominal_period"))
				i->out.smpmod = IEC61850_SV_SMPMOD_PER_NOMINAL_PERIOD;
			else if (!strcmp(smpmod, "samples_per_second"))
				i->out.smpmod = IEC61850_SV_SMPMOD_SAMPLES_PER_SECOND;
			else if (!strcmp(smpmod, "seconds_per_sample"))
				i->out.smpmod = IEC61850_SV_SMPMOD_SECONDS_PER_SAMPLE;
			else
				throw RuntimeError("Invalid value '{}' for setting 'smpmod'", smpmod);
		}

		i->out.svid = svid ? strdup(svid) : nullptr;

		ret = iec61850_parse_signals(json_signals, &i->out.signals, &n->out.signals);
		if (ret <= 0)
			throw RuntimeError("Failed to parse setting 'signals'");

		i->out.total_size = ret;
	}

	if (json_in) {
		i->in.enabled = true;

		json_signals = nullptr;
		ret = json_unpack_ex(json_in, &err, 0, "{ s: o }",
			"signals", &json_signals
		);
		if (ret)
			throw ConfigError(json_in, err, "node-config-node-iec61850-in");

		ret = iec61850_parse_signals(json_signals, &i->in.signals, &n->in.signals);
		if (ret <= 0)
			throw RuntimeError("Failed to parse setting 'signals'");

		i->in.total_size = ret;
	}

	return 0;
}

char * iec61850_sv_print(struct vnode *n)
{
	char *buf;
	struct iec61850_sv *i = (struct iec61850_sv *) n->_vd;

	buf = strf("interface=%s, app_id=%#x, dst_address=%s", i->interface, i->app_id, ether_ntoa(&i->dst_address));

	/* Publisher part */
	if (i->out.enabled) {
		strcatf(&buf, ", pub.svid=%s, pub.vlan_prio=%d, pub.vlan_id=%#x, pub.confrev=%d, pub.#fields=%zu",
			i->out.svid,
			i->out.vlan_priority,
			i->out.vlan_id,
			i->out.confrev,
			vlist_length(&i->out.signals)
		);
	}

	/* Subscriber part */
	if (i->in.enabled)
		strcatf(&buf, ", sub.#fields=%zu", vlist_length(&i->in.signals));

	return buf;
}

int iec61850_sv_start(struct vnode *n)
{
	int ret;
	struct iec61850_sv *i = (struct iec61850_sv *) n->_vd;

	/* Initialize publisher */
	if (i->out.enabled) {
		i->out.publisher = SVPublisher_create(nullptr, i->interface);
		i->out.asdu = SVPublisher_addASDU(i->out.publisher, i->out.svid, node_name_short(n), i->out.confrev);

		for (unsigned k = 0; k < vlist_length(&i->out.signals); k++) {
			struct iec61850_type_descriptor *td = (struct iec61850_type_descriptor *) vlist_at(&i->out.signals, k);

			switch (td->iec_type) {
				case IEC61850Type::INT8:
					SVPublisher_ASDU_addINT8(i->out.asdu);
					break;

				case IEC61850Type::INT32:
					SVPublisher_ASDU_addINT32(i->out.asdu);
					break;

				case IEC61850Type::FLOAT32:
					SVPublisher_ASDU_addFLOAT(i->out.asdu);
					break;

				case IEC61850Type::FLOAT64:
					SVPublisher_ASDU_addFLOAT64(i->out.asdu);
					break;

				default: { }
			}
		}

		if (i->out.smpmod >= 0)
			SVPublisher_ASDU_setSmpMod(i->out.asdu, i->out.smpmod);

		SVPublisher_ASDU_enableRefrTm(i->out.asdu);

//		if (s->out.smprate >= 0)
//			SV_ASDU_setSmpRate(i->out.asdu, i->out.smprate);

		/* Start publisher */
		SVPublisher_setupComplete(i->out.publisher);
	}

	/* Start subscriber */
	if (i->in.enabled) {
		struct iec61850_receiver *r = iec61850_receiver_create(iec61850_receiver::Type::SAMPLED_VALUES, i->interface);

		i->in.receiver = r->sv;
		i->in.subscriber = SVSubscriber_create(i->dst_address.ether_addr_octet, i->app_id);

		/* Install a callback handler for the subscriber */
		SVSubscriber_setListener(i->in.subscriber, iec61850_sv_listener, n);

		/* Connect the subscriber to the receiver */
		SVReceiver_addSubscriber(i->in.receiver, i->in.subscriber);

		/* Initialize pool and queue to pass samples between threads */
		ret = pool_init(&i->in.pool, 1024, SAMPLE_LENGTH(vlist_length(&n->in.signals)));
		if (ret)
			return ret;

		ret = queue_signalled_init(&i->in.queue, 1024);
		if (ret)
			return ret;

		for (unsigned k = 0; k < vlist_length(&i->in.signals); k++) {
			struct iec61850_type_descriptor *td = (struct iec61850_type_descriptor *) vlist_at(&i->in.signals, k);
			struct signal *sig = (struct signal *) vlist_at(&n->in.signals, k);

			if (sig->type == SignalType::INVALID)
				sig->type = td->type;
			else if (sig->type != td->type)
				return -1;
		}
	}

	return 0;
}

int iec61850_sv_stop(struct vnode *n)
{
	struct iec61850_sv *i = (struct iec61850_sv *) n->_vd;

	if (i->in.enabled)
		SVReceiver_removeSubscriber(i->in.receiver, i->in.subscriber);

	return 0;
}

int iec61850_sv_destroy(struct vnode *n)
{
	int ret;
	struct iec61850_sv *i = (struct iec61850_sv *) n->_vd;

	/* Deinitialize publisher */
	if (i->out.enabled && i->out.publisher)
		SVPublisher_destroy(i->out.publisher);

	/* Deinitialise subscriber */
	if (i->in.enabled) {
		ret = queue_signalled_destroy(&i->in.queue);
		if (ret)
			return ret;

		ret = pool_destroy(&i->in.pool);
		if (ret)
			return ret;
	}

	return 0;
}

int iec61850_sv_read(struct vnode *n, struct sample * const smps[], unsigned cnt)
{
	int pulled;
	struct iec61850_sv *i = (struct iec61850_sv *) n->_vd;
	struct sample *smpt[cnt];

	if (!i->in.enabled)
		return -1;

	pulled = queue_signalled_pull_many(&i->in.queue, (void **) smpt, cnt);

	sample_copy_many(smps, smpt, pulled);
	sample_decref_many(smpt, pulled);

	return pulled;
}

int iec61850_sv_write(struct vnode *n, struct sample * const smps[], unsigned cnt)
{
	struct iec61850_sv *i = (struct iec61850_sv *) n->_vd;

	if (!i->out.enabled)
		return -1;

	for (unsigned j = 0; j < cnt; j++) {
		unsigned offset = 0;
		for (unsigned k = 0; k < MIN(smps[j]->length, vlist_length(&i->out.signals)); k++) {
			struct iec61850_type_descriptor *td = (struct iec61850_type_descriptor *) vlist_at(&i->out.signals, k);

			int ival = 0;
			double fval = 0;

			switch (td->iec_type) {
				case IEC61850Type::INT8:
				case IEC61850Type::INT32:
					ival = sample_format(smps[j], k) == SignalType::FLOAT ? smps[j]->data[k].f : smps[j]->data[k].i;
					break;

				case IEC61850Type::FLOAT32:
				case IEC61850Type::FLOAT64:
					fval = sample_format(smps[j], k) == SignalType::FLOAT ? smps[j]->data[k].f : smps[j]->data[k].i;
					break;

				default: { }
			}

			switch (td->iec_type) {
				case IEC61850Type::INT8:
					SVPublisher_ASDU_setINT8(i->out.asdu,    offset, ival);
					break;

				case IEC61850Type::INT32:
					SVPublisher_ASDU_setINT32(i->out.asdu,   offset, ival);
					break;

				case IEC61850Type::FLOAT32:
					SVPublisher_ASDU_setFLOAT(i->out.asdu,   offset, fval);
					break;

				case IEC61850Type::FLOAT64:
					SVPublisher_ASDU_setFLOAT64(i->out.asdu, offset, fval);
					break;

				default: { }
			}

			offset += td->size;
		}

		SVPublisher_ASDU_setSmpCnt(i->out.asdu, smps[j]->sequence);

		if (smps[j]->flags & (int) SampleFlags::HAS_TS_ORIGIN) {
			uint64_t refrtm = smps[j]->ts.origin.tv_sec * 1000 + smps[j]->ts.origin.tv_nsec / 1000000;

			SVPublisher_ASDU_setRefrTm(i->out.asdu, refrtm);
		}

		SVPublisher_publish(i->out.publisher);
	}

	return cnt;
}

int iec61850_sv_poll_fds(struct vnode *n, int fds[])
{
	struct iec61850_sv *i = (struct iec61850_sv *) n->_vd;

	fds[0] = queue_signalled_fd(&i->in.queue);

	return 1;
}

static struct vnode_type p;

__attribute__((constructor(110)))
static void register_plugin() {
	p.name		= "iec61850-9-2";
	p.description	= "IEC 61850-9-2 (Sampled Values)";
	p.vectorize	= 0;
	p.size		= sizeof(struct iec61850_sv);
	p.start	= iec61850_type_start;
	p.stop	= iec61850_type_stop;
	p.destroy	= iec61850_sv_destroy;
	p.parse		= iec61850_sv_parse;
	p.print		= iec61850_sv_print;
	p.start		= iec61850_sv_start;
	p.stop		= iec61850_sv_stop;
	p.read		= iec61850_sv_read;
	p.write		= iec61850_sv_write;
	p.poll_fds	= iec61850_sv_poll_fds;

	if (!node_types)
		node_types = new NodeTypeList();

	node_types->push_back(&p);
}

#endif /* CONFIG_IEC61850_SAMPLED_VALUES_SUPPORT */