/*
 * Copyright (C) 2018 "IoT.bzh"
 * Author Jonathan Aillet <jonathan.aillet@iot.bzh>
 *
 * 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 <afb/afb-binding.h>

#include "4a-hal-utilities-data.h"

#include "../4a-internals-hal/4a-internals-hal-api-loader.h"

#include "4a-hal-manager.h"
#include "4a-hal-manager-cb.h"

/*******************************************************************************
 *		HAL Manager verbs table					       *
 ******************************************************************************/

// Hal manager exported verbs
afb_verb_t HalManagerApiStaticVerbs[] =
{
	/* VERB'S NAME			FUNCTION TO CALL			SHORT DESCRIPTION */
	{ .verb = "ping",		.callback = HalMgrPing,			.info = "Ping test"},
	{ .verb = "loaded",		.callback = HalMgrLoaded,		.info = "Show loaded HAL"},
	{ .verb = "load",		.callback = HalMgrLoad,			.info = "Load an external HAL to HAL Manager"},
	{ .verb = "unload",		.callback = HalMgrUnload,		.info = "Unload an external HAL to HAL Manager"},
	{ .verb = "subscribe",		.callback = HalMgrSubscribeEvent,	.info = "Subscribe to an event"},
	{ .verb = "unsuscribe",		.callback = HalMgrUnsubscribeEvent,	.info = "Unsubscribe to an event"},
	{ .verb = NULL }		// Marker for end of the array
};

/*******************************************************************************
 *		Dynamic API functions for hal manager			       *
 ******************************************************************************/

static int HalMgrInitApi(afb_api_t apiHandle)
{
	struct HalData *currentHalData;
	struct HalMgrData *halMgrData;

	if(! apiHandle)
		return -1;

	// Retrieve section config from api handle
	halMgrData = (struct HalMgrData *) afb_api_get_userdata(apiHandle);
	if(! halMgrData)
		return -2;

	if(HalUtlInitializeHalMgrData(apiHandle, halMgrData, HAL_MANAGER_API_NAME, HAL_MANAGER_API_INFO))
		return -3;

	cds_list_for_each_entry(currentHalData, &halMgrData->halDataListHead, node) {
		if(! currentHalData->apiName)
			return -4;
		else if(afb_api_require_api(apiHandle, currentHalData->apiName, 1))
			return -5;
	}

	return 0;
}

static int HalMgrLoadApi(void *cbdata, afb_api_t apiHandle)
{
	struct HalMgrData *halMgrData;

	if(! cbdata || ! apiHandle)
		return -1;

	halMgrData = (struct HalMgrData *) cbdata;

	// Save closure as api's data context
	afb_api_set_userdata(apiHandle, halMgrData);

	// Add static 'hal-manager' verbs
	if(afb_api_set_verbs_v3(apiHandle, HalManagerApiStaticVerbs)) {
		AFB_API_ERROR(apiHandle, "Load section : fail to register static verbs");
		return -2;
	}

	// Declare an event manager for Hal Manager
	afb_api_on_event(apiHandle, HalMgrDispatchApiEvent);

	// Init Api function (does not receive user closure ???)
	afb_api_on_init(apiHandle, HalMgrInitApi);

	afb_api_seal(apiHandle);

	return 0;
}

int HalMgrCreateApi(afb_api_t apiHandle, struct HalMgrData *halMgrData)
{
	if(! apiHandle || ! halMgrData)
		return -1;

	// Create one API
	return afb_api_new_api(apiHandle, HAL_MANAGER_API_NAME, HAL_MANAGER_API_INFO, 1, HalMgrLoadApi, halMgrData) ? 0 : -1;
}

/*******************************************************************************
 *		Startup function					       *
 ******************************************************************************/

int afbBindingEntry(afb_api_t apiHandle)
{
	struct HalMgrData *halMgrData;

	if(! apiHandle)
		return -1;

	AFB_API_NOTICE(apiHandle, "Binding start");

	halMgrData = (struct HalMgrData *) calloc(1, sizeof(struct HalMgrData));
	if(! halMgrData)
		return -2;

	CDS_INIT_LIST_HEAD(&halMgrData->halDataListHead);

	// Load Hal-Manager using Api v3
	if(HalMgrCreateApi(apiHandle, halMgrData))
		return -3;

	// Load internals Hal using Api v3
	if(InternalHalCreateAllApi(apiHandle, halMgrData))
		return -4;

	return 0;
}