/*
 *  Hamlib Interface - provides registering for dynamically loadable backends.
 *  Copyright (c) 2000-2005 by Stephane Fillod
 *
 *
 *   This library is free software; you can redistribute it and/or
 *   modify it under the terms of the GNU Lesser General Public
 *   License as published by the Free Software Foundation; either
 *   version 2.1 of the License, or (at your option) any later version.
 *
 *   This library 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
 *   Lesser General Public License for more details.
 *
 *   You should have received a copy of the GNU Lesser General Public
 *   License along with this library; if not, write to the Free Software
 *   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 *
 */

/**
 * \brief Dynamic registration of backends
 * \file register.c
 *
 * doc todo: Let's explain what's going on here!
 */

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include <errno.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <stdio.h>
#include <sys/types.h>

#include <register.h>

#include <hamlib/rig.h>

#ifndef PATH_MAX
# define PATH_MAX       1024
#endif

#define RIG_BACKEND_MAX 32

#define DEFINE_INITRIG_BACKEND(backend) \
	int MAKE_VERSIONED_FN(PREFIX_INITRIG, ABI_VERSION, backend(void *be_handle)); \
	rig_model_t MAKE_VERSIONED_FN(PREFIX_PROBERIG, ABI_VERSION, backend(hamlib_port_t *port, rig_probe_func_t cfunc, rig_ptr_t data))

#define RIG_FUNCNAMA(backend) MAKE_VERSIONED_FN(PREFIX_INITRIG, ABI_VERSION, backend)
#define RIG_FUNCNAMB(backend) MAKE_VERSIONED_FN(PREFIX_PROBERIG, ABI_VERSION, backend)

#define RIG_FUNCNAM(backend) RIG_FUNCNAMA(backend),RIG_FUNCNAMB(backend)

/*
 * RIG_BACKEND_LIST is defined here, please keep it up to data,
 * 	ie. each time you give birth to a new backend
 * Also, it should be possible to register "external" backend,
 * that is backend that were not known by Hamlib at compile time.
 * Maybe, riglist.h should reserve some numbers for them? --SF
 */
DEFINE_INITRIG_BACKEND(dummy);
DEFINE_INITRIG_BACKEND(yaesu);
DEFINE_INITRIG_BACKEND(kenwood);
DEFINE_INITRIG_BACKEND(icom);
DEFINE_INITRIG_BACKEND(pcr);
DEFINE_INITRIG_BACKEND(aor);
DEFINE_INITRIG_BACKEND(jrc);
DEFINE_INITRIG_BACKEND(uniden);
DEFINE_INITRIG_BACKEND(drake);
DEFINE_INITRIG_BACKEND(lowe);
DEFINE_INITRIG_BACKEND(racal);
DEFINE_INITRIG_BACKEND(wj);
DEFINE_INITRIG_BACKEND(skanti);
DEFINE_INITRIG_BACKEND(winradio);
DEFINE_INITRIG_BACKEND(tentec);
DEFINE_INITRIG_BACKEND(alinco);
DEFINE_INITRIG_BACKEND(kachina);
DEFINE_INITRIG_BACKEND(tapr);
DEFINE_INITRIG_BACKEND(flexradio);
DEFINE_INITRIG_BACKEND(rft);
DEFINE_INITRIG_BACKEND(kit);
DEFINE_INITRIG_BACKEND(tuner);
DEFINE_INITRIG_BACKEND(rs);
DEFINE_INITRIG_BACKEND(prm80);
DEFINE_INITRIG_BACKEND(adat);



/*! \def rig_backend_list
 *  \brief Static list of rig models.
 *
 *  This is a NULL terminated list of available rig backends. Each entry
 *  in the list consists of two fields: The branch number, which is an integer,
 *  and the branch name, which is a character string.
 */
static struct {
	int be_num;
	const char *be_name;
	int (* be_init_all)(void * handle);
	rig_model_t (* be_probe_all)(hamlib_port_t*, rig_probe_func_t, rig_ptr_t);
} rig_backend_list[RIG_BACKEND_MAX] =
{
		{ RIG_DUMMY, RIG_BACKEND_DUMMY, RIG_FUNCNAMA(dummy) },
		{ RIG_YAESU, RIG_BACKEND_YAESU, RIG_FUNCNAM(yaesu) },
		{ RIG_KENWOOD, RIG_BACKEND_KENWOOD, RIG_FUNCNAM(kenwood) },
		{ RIG_ICOM, RIG_BACKEND_ICOM, RIG_FUNCNAM(icom) },
		{ RIG_PCR, RIG_BACKEND_PCR, RIG_FUNCNAMA(pcr) },
		{ RIG_AOR, RIG_BACKEND_AOR, RIG_FUNCNAMA(aor) },
		{ RIG_JRC, RIG_BACKEND_JRC, RIG_FUNCNAMA(jrc) },
		{ RIG_UNIDEN, RIG_BACKEND_UNIDEN, RIG_FUNCNAM(uniden) },
		{ RIG_DRAKE, RIG_BACKEND_DRAKE, RIG_FUNCNAM(drake) },
		{ RIG_LOWE, RIG_BACKEND_LOWE, RIG_FUNCNAM(lowe) },
		{ RIG_RACAL, RIG_BACKEND_RACAL, RIG_FUNCNAMA(racal) },
		{ RIG_WJ, RIG_BACKEND_WJ, RIG_FUNCNAMA(wj) },
		{ RIG_SKANTI, RIG_BACKEND_SKANTI, RIG_FUNCNAMA(skanti) },
		{ RIG_WINRADIO, RIG_BACKEND_WINRADIO, RIG_FUNCNAMA(winradio) },
		{ RIG_TENTEC, RIG_BACKEND_TENTEC, RIG_FUNCNAMA(tentec) },
		{ RIG_ALINCO, RIG_BACKEND_ALINCO, RIG_FUNCNAMA(alinco) },
		{ RIG_KACHINA, RIG_BACKEND_KACHINA, RIG_FUNCNAMA(kachina) },
		{ RIG_TAPR, RIG_BACKEND_TAPR, RIG_FUNCNAMA(tapr) },
		{ RIG_FLEXRADIO, RIG_BACKEND_FLEXRADIO, RIG_FUNCNAMA(flexradio) },
		{ RIG_RFT, RIG_BACKEND_RFT, RIG_FUNCNAMA(rft) },
		{ RIG_KIT, RIG_BACKEND_KIT, RIG_FUNCNAMA(kit) },
		{ RIG_TUNER, RIG_BACKEND_TUNER, RIG_FUNCNAMA(tuner) },
		{ RIG_RS, RIG_BACKEND_RS, RIG_FUNCNAMA(rs) },
		{ RIG_PRM80, RIG_BACKEND_PRM80, RIG_FUNCNAMA(prm80) },
		{ RIG_ADAT, RIG_BACKEND_ADAT, RIG_FUNCNAM(adat) },
		{ 0, NULL }, /* end */
};

/*
 * This struct to keep track of known rig models.
 * It is chained, and used in a hash table, see below.
 */
struct rig_list {
	const struct rig_caps *caps;
	struct rig_list *next;
};

#define RIGLSTHASHSZ 16
#define HASH_FUNC(a) ((a)%RIGLSTHASHSZ)

/*
 * The rig_hash_table is a hash table pointing to a list of next==NULL
 * 	terminated caps.
 */
static struct rig_list *rig_hash_table[RIGLSTHASHSZ] = { NULL, };


static int rig_lookup_backend(rig_model_t rig_model);

/*
 * Basically, this is a hash insert function that doesn't check for dup!
 */
int HAMLIB_API rig_register(const struct rig_caps *caps)
{
	int hval;
	struct rig_list *p;

	if (!caps)
		return -RIG_EINVAL;

	rig_debug(RIG_DEBUG_VERBOSE, "rig_register (%d)\n",caps->rig_model);

#ifndef DONT_WANT_DUP_CHECK
	if (rig_get_caps(caps->rig_model)!=NULL)
		return -RIG_EINVAL;
#endif

	p = (struct rig_list*)malloc(sizeof(struct rig_list));
	if (!p)
		return -RIG_ENOMEM;

	hval = HASH_FUNC(caps->rig_model);
	p->caps = caps;
	// p->handle = NULL;
	p->next = rig_hash_table[hval];
	rig_hash_table[hval] = p;

	return RIG_OK;
}

/*
 * Get rig capabilities.
 * ie. rig_hash_table lookup
 */

const struct rig_caps * HAMLIB_API rig_get_caps(rig_model_t rig_model)
{
	struct rig_list *p;

	for (p = rig_hash_table[HASH_FUNC(rig_model)]; p; p=p->next) {
		if (p->caps->rig_model == rig_model)
			return p->caps;
	}

	return NULL;	/* sorry, caps not registered! */
}

/*
 * lookup for backend index in rig_backend_list table,
 * according to BACKEND_NUM
 * return -1 if not found.
 */
static int rig_lookup_backend(rig_model_t rig_model)
{
	int i;

	for (i=0; i<RIG_BACKEND_MAX && rig_backend_list[i].be_name; i++) {
		if (RIG_BACKEND_NUM(rig_model) ==
					rig_backend_list[i].be_num)
			return i;
	}

	return -1;
}

/*
 * rig_check_backend
 * check the backend declaring this model has been loaded
 * and if not loaded already, load it!
 * This permits seamless operation in rig_init.
 */
int HAMLIB_API rig_check_backend(rig_model_t rig_model)
{
	const struct rig_caps *caps;
	int be_idx;
	int retval;

	/* already loaded ? */
	caps = rig_get_caps(rig_model);
	if (caps)
		return RIG_OK;

	be_idx = rig_lookup_backend(rig_model);

	/*
	 * Never heard about this backend family!
	 */
	if (be_idx == -1) {
		rig_debug(RIG_DEBUG_VERBOSE, "rig_check_backend: unsupported "
					"backend %d for model %d\n",
					RIG_BACKEND_NUM(rig_model), rig_model);
		return -RIG_ENAVAIL;
	}

	retval = rig_load_backend(rig_backend_list[be_idx].be_name);

	return retval;
}



int HAMLIB_API rig_unregister(rig_model_t rig_model)
{
	int hval;
	struct rig_list *p,*q;

	hval = HASH_FUNC(rig_model);
	q = NULL;
	for (p = rig_hash_table[hval]; p; p=p->next) {
		if (p->caps->rig_model == rig_model) {
			if (q == NULL)
				rig_hash_table[hval] = p->next;
			else
				q->next = p->next;

			free(p);
			return RIG_OK;
		}
		q = p;
	}

	return -RIG_EINVAL;	/* sorry, caps not registered! */
}

/*
 * rig_list_foreach
 * executes cfunc on all the elements stored in the rig hash list
 */
int HAMLIB_API rig_list_foreach(int (*cfunc)(const struct rig_caps*, rig_ptr_t),rig_ptr_t data)
{
	struct rig_list *p;
	int i;

	if (!cfunc)
		return -RIG_EINVAL;

	for (i=0; i<RIGLSTHASHSZ; i++) {
		for (p=rig_hash_table[i]; p; p=p->next)
			if ((*cfunc)(p->caps,data) == 0)
				return RIG_OK;
	}

	return RIG_OK;
}

static int dummy_rig_probe(const hamlib_port_t *p, rig_model_t model, rig_ptr_t data)
{
	rig_debug(RIG_DEBUG_TRACE, "Found rig, model %d\n", model);
	return RIG_OK;
}

/*
 * rig_probe_first
 * called straight by rig_probe
 */
rig_model_t rig_probe_first(hamlib_port_t *p)
{
	int i;
	rig_model_t model;

	for (i=0; i<RIG_BACKEND_MAX && rig_backend_list[i].be_name; i++) {
		if (rig_backend_list[i].be_probe_all) {
			model = (*rig_backend_list[i].be_probe_all)(p, dummy_rig_probe, (rig_ptr_t)NULL);
			/* stop at first one found */
			if (model != RIG_MODEL_NONE)
				return model;
		}
	}
	return RIG_MODEL_NONE;
}

/*
 * rig_probe_all_backends
 * called straight by rig_probe_all
 */
int rig_probe_all_backends(hamlib_port_t *p, rig_probe_func_t cfunc, rig_ptr_t data)
{
	int i;

	for (i=0; i<RIG_BACKEND_MAX && rig_backend_list[i].be_name; i++) {
		if (rig_backend_list[i].be_probe_all) {
			(*rig_backend_list[i].be_probe_all)(p, cfunc, data);
		}
	}
	return RIG_OK;
}


int rig_load_all_backends()
{
	int i;

	for (i=0; i<RIG_BACKEND_MAX && rig_backend_list[i].be_name; i++) {
			rig_load_backend(rig_backend_list[i].be_name);
	}

	return RIG_OK;
}


typedef int (*backend_init_t)(rig_ptr_t);

/*
 * rig_load_backend
 */
int HAMLIB_API rig_load_backend(const char *be_name)
{
	int i;
	backend_init_t be_init;

	for (i=0; i<RIG_BACKEND_MAX && rig_backend_list[i].be_name; i++) {
		if (!strcmp(be_name, rig_backend_list[i].be_name)) {
			be_init = rig_backend_list[i].be_init_all ;
			if(be_init)
			{
				return (*be_init)(NULL);
			}
			else
			{
				return -RIG_EINVAL;
			}
		}
	}

	return -RIG_EINVAL;
}