/*
 * Copyright (C) 2015, 2016, 2017 "IoT.bzh"
 * Author "Fulup Ar Foll"
 *
 * Licensed under the Apache License, Version 2.0 (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.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
#define _GNU_SOURCE
#include <stdio.h>
#include <string.h>
#include <pthread.h>

#include <json-c/json.h>

#define AFB_BINDING_VERSION 2
#include <afb/afb-binding.h>

static pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER;

struct event
{
	struct event *next;
	afb_event_t event;
	char tag[1];
};

static struct event *events = 0;

/* searchs the event of tag */
static struct event *event_get(const char *tag)
{
	struct event *e = events;
	while(e && strcmp(e->tag, tag))
		e = e->next;
	return e;
}

/* deletes the event of tag */
static int event_del(const char *tag)
{
	struct event *e, **p;

	/* check exists */
	e = event_get(tag);
	if (!e) return -1;

	/* unlink */
	p = &events;
	while(*p != e) p = &(*p)->next;
	*p = e->next;

	/* destroys */
	afb_event_unref(e->event);
	free(e);
	return 0;
}

/* creates the event of tag */
static int event_add(const char *tag, const char *name)
{
	struct event *e;

	/* check valid tag */
	e = event_get(tag);
	if (e) return -1;

	/* creation */
	e = malloc(strlen(tag) + sizeof *e);
	if (!e) return -1;
	strcpy(e->tag, tag);

	/* make the event */
	e->event = afb_daemon_make_event(name);
	if (!e->event.closure) { free(e); return -1; }

	/* link */
	e->next = events;
	events = e;
	return 0;
}

static int event_subscribe(afb_req_t request, const char *tag)
{
	struct event *e;
	e = event_get(tag);
	return e ? afb_req_subscribe(request, e->event) : -1;
}

static int event_unsubscribe(afb_req_t request, const char *tag)
{
	struct event *e;
	e = event_get(tag);
	return e ? afb_req_unsubscribe(request, e->event) : -1;
}

static int event_push(struct json_object *args, const char *tag)
{
	struct event *e;
	e = event_get(tag);
	return e ? afb_event_push(e->event, json_object_get(args)) : -1;
}

static int event_broadcast(struct json_object *args, const char *tag)
{
	struct event *e;
	e = event_get(tag);
	return e ? afb_event_broadcast(e->event, json_object_get(args)) : -1;
}

// Sample Generic Ping Debug API
static void ping(afb_req_t request, json_object *jresp, const char *tag)
{
	static int pingcount = 0;
	json_object *query = afb_req_json(request);
	afb_req_success_f(request, jresp, "Ping Binder Daemon tag=%s count=%d query=%s", tag, ++pingcount, json_object_to_json_string(query));
}

static void pingSample (afb_req_t request)
{
	ping(request, json_object_new_string ("Some String"), "pingSample");
}

static void pingFail (afb_req_t request)
{
	afb_req_fail(request, "failed", "Ping Binder Daemon fails");
}

static void pingNull (afb_req_t request)
{
	ping(request, NULL, "pingNull");
}

static void pingBug (afb_req_t request)
{
	ping((afb_req_t){NULL,NULL}, NULL, "pingBug");
}

static void pingEvent(afb_req_t request)
{
	json_object *query = afb_req_json(request);
	afb_daemon_broadcast_event("event", json_object_get(query));
	ping(request, json_object_get(query), "event");
}


// For samples https://linuxprograms.wordpress.com/2010/05/20/json-c-libjson-tutorial/
static void pingJson (afb_req_t request) {
    json_object *jresp, *embed;

    jresp = json_object_new_object();
    json_object_object_add(jresp, "myString", json_object_new_string ("Some String"));
    json_object_object_add(jresp, "myInt", json_object_new_int (1234));

    embed  = json_object_new_object();
    json_object_object_add(embed, "subObjString", json_object_new_string ("Some String"));
    json_object_object_add(embed, "subObjInt", json_object_new_int (5678));

    json_object_object_add(jresp,"eobj", embed);

    ping(request, jresp, "pingJson");
}

static void subcallcb (void *prequest, int status, json_object *object)
{
	afb_req_t request = afb_req_unstore(prequest);
	if (status < 0)
		afb_req_fail(request, "failed", json_object_to_json_string(object));
	else
		afb_req_success(request, json_object_get(object), NULL);
	afb_req_unref(request);
}

static void subcall (afb_req_t request)
{
	const char *api = afb_req_value(request, "api");
	const char *verb = afb_req_value(request, "verb");
	const char *args = afb_req_value(request, "args");
	json_object *object = api && verb && args ? json_tokener_parse(args) : NULL;

	if (object == NULL)
		afb_req_fail(request, "failed", "bad arguments");
	else
		afb_req_subcall(request, api, verb, object, subcallcb, afb_req_store(request));
}

static void subcallreqcb (void *prequest, int status, json_object *object, afb_req_t request)
{
	if (status < 0)
		afb_req_fail(request, "failed", json_object_to_json_string(object));
	else
		afb_req_success(request, json_object_get(object), NULL);
}

static void subcallreq (afb_req_t request)
{
	const char *api = afb_req_value(request, "api");
	const char *verb = afb_req_value(request, "verb");
	const char *args = afb_req_value(request, "args");
	json_object *object = api && verb && args ? json_tokener_parse(args) : NULL;

	if (object == NULL)
		afb_req_fail(request, "failed", "bad arguments");
	else
		afb_req_subcall_req(request, api, verb, object, subcallreqcb, NULL);
}

static void subcallsync (afb_req_t request)
{
	int rc;
	const char *api = afb_req_value(request, "api");
	const char *verb = afb_req_value(request, "verb");
	const char *args = afb_req_value(request, "args");
	json_object *result, *object = api && verb && args ? json_tokener_parse(args) : NULL;

	if (object == NULL)
		afb_req_fail(request, "failed", "bad arguments");
	else {
		rc = afb_req_subcall_sync(request, api, verb, object, &result);
		if (rc >= 0)
			afb_req_success(request, result, NULL);
		else {
			afb_req_fail(request, "failed", json_object_to_json_string(result));
			json_object_put(result);
		}
	}
}

static void eventadd (afb_req_t request)
{
	const char *tag = afb_req_value(request, "tag");
	const char *name = afb_req_value(request, "name");

	pthread_mutex_lock(&mutex);
	if (tag == NULL || name == NULL)
		afb_req_fail(request, "failed", "bad arguments");
	else if (0 != event_add(tag, name))
		afb_req_fail(request, "failed", "creation error");
	else
		afb_req_success(request, NULL, NULL);
	pthread_mutex_unlock(&mutex);
}

static void eventdel (afb_req_t request)
{
	const char *tag = afb_req_value(request, "tag");

	pthread_mutex_lock(&mutex);
	if (tag == NULL)
		afb_req_fail(request, "failed", "bad arguments");
	else if (0 != event_del(tag))
		afb_req_fail(request, "failed", "deletion error");
	else
		afb_req_success(request, NULL, NULL);
	pthread_mutex_unlock(&mutex);
}

static void eventsub (afb_req_t request)
{
	const char *tag = afb_req_value(request, "tag");

	pthread_mutex_lock(&mutex);
	if (tag == NULL)
		afb_req_fail(request, "failed", "bad arguments");
	else if (0 != event_subscribe(request, tag))
		afb_req_fail(request, "failed", "subscription error");
	else
		afb_req_success(request, NULL, NULL);
	pthread_mutex_unlock(&mutex);
}

static void eventunsub (afb_req_t request)
{
	const char *tag = afb_req_value(request, "tag");

	pthread_mutex_lock(&mutex);
	if (tag == NULL)
		afb_req_fail(request, "failed", "bad arguments");
	else if (0 != event_unsubscribe(request, tag))
		afb_req_fail(request, "failed", "unsubscription error");
	else
		afb_req_success(request, NULL, NULL);
	pthread_mutex_unlock(&mutex);
}

static void eventpush (afb_req_t request)
{
	const char *tag = afb_req_value(request, "tag");
	const char *data = afb_req_value(request, "data");
	json_object *object = data ? json_tokener_parse(data) : NULL;

	pthread_mutex_lock(&mutex);
	if (tag == NULL)
		afb_req_fail(request, "failed", "bad arguments");
	else if (0 > event_push(object, tag))
		afb_req_fail(request, "failed", "push error");
	else
		afb_req_success(request, NULL, NULL);
	pthread_mutex_unlock(&mutex);
	json_object_put(object);
}

static void callcb (void *prequest, int status, json_object *object)
{
	afb_req_t request = afb_req_unstore(prequest);
	if (status < 0)
		afb_req_fail(request, "failed", json_object_to_json_string(object));
	else
		afb_req_success(request, json_object_get(object), NULL);
	afb_req_unref(request);
}

static void call (afb_req_t request)
{
	const char *api = afb_req_value(request, "api");
	const char *verb = afb_req_value(request, "verb");
	const char *args = afb_req_value(request, "args");
	json_object *object = api && verb && args ? json_tokener_parse(args) : NULL;

	if (object == NULL)
		afb_req_fail(request, "failed", "bad arguments");
	else
		afb_service_call(api, verb, object, callcb, afb_req_store(request));
}

static void callsync (afb_req_t request)
{
	int rc;
	const char *api = afb_req_value(request, "api");
	const char *verb = afb_req_value(request, "verb");
	const char *args = afb_req_value(request, "args");
	json_object *result, *object = api && verb && args ? json_tokener_parse(args) : NULL;

	if (object == NULL)
		afb_req_fail(request, "failed", "bad arguments");
	else {
		rc = afb_service_call_sync(api, verb, object, &result);
		if (rc >= 0)
			afb_req_success(request, result, NULL);
		else {
			afb_req_fail(request, "failed", json_object_to_json_string(result));
			json_object_put(result);
		}
	}
}

static void verbose (afb_req_t request)
{
	int level = 5;
	json_object *query = afb_req_json(request), *l;

	if (json_object_is_type(query,json_type_int))
		level = json_object_get_int(query);
	else if (json_object_object_get_ex(query, "level", &l) && json_object_is_type(l, json_type_int))
		level = json_object_get_int(l);

	if (!json_object_object_get_ex(query,"message",&l))
		l = query;

	AFB_REQ_VERBOSE(request, level, "verbose called for %s", json_object_get_string(l));
	afb_req_success(request, NULL, NULL);
}

static void exitnow (afb_req_t request)
{
	int code = 0;
	json_object *query = afb_req_json(request), *l;

	if (json_object_is_type(query,json_type_int))
		code = json_object_get_int(query);
	else if (json_object_object_get_ex(query, "code", &l) && json_object_is_type(l, json_type_int))
		code = json_object_get_int(l);

	if (!json_object_object_get_ex(query,"reason",&l))
		l = NULL;

	AFB_REQ_NOTICE(request, "in phase of exiting with code %d, reason: %s", code, l ? json_object_get_string(l) : "unknown");
	afb_req_success(request, NULL, NULL);
	exit(code);
}

static void broadcast(afb_req_t request)
{
	const char *tag = afb_req_value(request, "tag");
	const char *name = afb_req_value(request, "name");
	const char *data = afb_req_value(request, "data");
	json_object *object = data ? json_tokener_parse(data) : NULL;

	if (tag != NULL) {
		pthread_mutex_lock(&mutex);
		if (0 > event_broadcast(object, tag))
			afb_req_fail(request, "failed", "broadcast error");
		else
			afb_req_success(request, NULL, NULL);
		pthread_mutex_unlock(&mutex);
	} else if (name != NULL) {
		if (0 > afb_daemon_broadcast_event(name, object))
			afb_req_fail(request, "failed", "broadcast error");
		else
			afb_req_success(request, NULL, NULL);
	} else {
		afb_req_fail(request, "failed", "bad arguments");
	}
	json_object_put(object);
}

static void hasperm (afb_req_t request)
{
	const char *perm = afb_req_value(request, "perm");
	if (afb_req_has_permission(request, perm))
		afb_req_success_f(request, NULL, "permission %s granted", perm?:"(null)");
	else
		afb_req_fail_f(request, "not-granted", "permission %s NOT granted", perm?:"(null)");
}

static void appid (afb_req_t request)
{
	char *aid = afb_req_get_application_id(request);
	afb_req_success_f(request, aid ? json_object_new_string(aid) : NULL, "application is %s", aid?:"?");
	free(aid);
}

static void uid (afb_req_t request)
{
	int uid = afb_req_get_uid(request);
	afb_req_success_f(request, json_object_new_int(uid), "uid is %d", uid);
}

static void closess (afb_req_t request)
{
	afb_req_session_close(request);
	afb_req_success(request, NULL, "session closed");
}

static void setloa (afb_req_t request)
{
	int loa = json_object_get_int(afb_req_json(request));
	afb_req_session_set_LOA(request, loa);
	afb_req_success_f(request, NULL, "LOA set to %d", loa);
}

static void setctx (afb_req_t request, int force)
{
	struct json_object *x = afb_req_json(request);
	afb_req_context_make(request, force, (void*)json_object_get, (void*)json_object_put, x);
	afb_req_success_f(request, json_object_get(x), "context set (force = %d)", force);
}

static void setctxset (afb_req_t request)
{
	setctx(request, 1);
}

static void setctxif (afb_req_t request)
{
	setctx(request, 0);
}

static void getctx (afb_req_t request)
{
	struct json_object *x = afb_req_context_make(request, 0, 0, 0, 0);
	afb_req_success(request, json_object_get(x), "returning the context");
}

static void info (afb_req_t request)
{
	afb_req_success(request, afb_req_get_client_info(request), NULL);
}

static int preinit()
{
	AFB_NOTICE("hello binding comes to live");
	return 0;
}

static int init()
{
	AFB_NOTICE("hello binding starting");
	return 0;
}

static void onevent(const char *event, struct json_object *object)
{
	AFB_NOTICE("received event %s(%s)", event, json_object_to_json_string(object));
}

// NOTE: this sample does not use session to keep test a basic as possible
//       in real application most APIs should be protected with AFB_SESSION_CHECK
static const afb_verb_v2 verbs[]= {
  { .verb="ping",        .callback=pingSample },
  { .verb="pingfail",    .callback=pingFail },
  { .verb="pingnull",    .callback=pingNull },
  { .verb="pingbug",     .callback=pingBug },
  { .verb="pingJson",    .callback=pingJson },
  { .verb="pingevent",   .callback=pingEvent },
  { .verb="subcall",     .callback=subcall },
  { .verb="subcallreq",  .callback=subcallreq },
  { .verb="subcallsync", .callback=subcallsync },
  { .verb="eventadd",    .callback=eventadd },
  { .verb="eventdel",    .callback=eventdel },
  { .verb="eventsub",    .callback=eventsub },
  { .verb="eventunsub",  .callback=eventunsub },
  { .verb="eventpush",   .callback=eventpush },
  { .verb="call",        .callback=call },
  { .verb="callsync",    .callback=callsync },
  { .verb="verbose",     .callback=verbose },
  { .verb="broadcast",   .callback=broadcast },
  { .verb="hasperm",     .callback=hasperm },
  { .verb="appid",       .callback=appid },
  { .verb="uid",         .callback=uid },
  { .verb="exit",        .callback=exitnow },
  { .verb="close",       .callback=closess },
  { .verb="set-loa",     .callback=setloa },
  { .verb="setctx",      .callback=setctxset },
  { .verb="setctxif",    .callback=setctxif },
  { .verb="getctx",      .callback=getctx },
  { .verb="info",        .callback=info },
  { .verb=NULL}
};

#if !defined(APINAME)
#define APINAME "hello2"
#endif

const afb_binding_v2 afbBindingV2 = {
	.api = APINAME,
	.specification = NULL,
	.verbs = verbs,
	.preinit = preinit,
	.init = init,
	.onevent = onevent
};