/*
 * 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 <filescan-utils.h>
#include <wrap-json.h>

#include <afb/afb-binding.h>

#include <ctl-config.h>

#include "4a-internals-hal-api-loader.h"
#include "4a-internals-hal-alsacore-link.h"
#include "4a-internals-hal-cb.h"
#include "4a-internals-hal-mixer-link.h"

/*******************************************************************************
 *		Json parsing functions using controller			       *
 ******************************************************************************/

// Config Section definition
static CtlSectionT ctrlSectionsDefault[] =
{
	{ .key = "resources",		.loadCB = PluginConfig },
	{ .key = "halmixer",		.loadCB = InternalHalHalMixerConfig },
	{ .key = "onload",		.loadCB = OnloadConfig },
	{ .key = "controls",		.loadCB = ControlConfig },
	{ .key = "events",		.loadCB = EventConfig },
	{ .key = "halmap",		.loadCB = InternalHalHalMapConfig },
	{ .key = NULL }
};

/*******************************************************************************
 *		Dynamic HAL verbs' functions				       *
 ******************************************************************************/

// Every HAL export the same API & Interface Mapping from SndCard to AudioLogic is done through alsaHalSndCardT
static afb_verb_t InternalHalApiStaticVerbs[] =
{
	/* VERB'S NAME			FUNCTION TO CALL		SHORT DESCRIPTION */
	{ .verb = "info",		.callback = InternalHalInfo,		.info = "List available streams/controls for this api" },
	{ .verb = "subscribe",		.callback = InternalHalSubscribe,	.info = "Subscribe to event(s) for values changes (streams/controls) for this api" },
	{ .verb = "unsubscribe",	.callback = InternalHalUnsubscribe,	.info = "Unsubscribe to event(s) for values changes (streams/controls) for this api" },
	{ .verb = NULL }		// Marker for end of the array
};

/*******************************************************************************
 *		Dynamic API functions for internals hal			       *
 ******************************************************************************/

static int InternalHalInitOneApi(afb_api_t apiHandle)
{
	CtlConfigT *ctrlConfig;
	struct HalData *currentHalData;

	if(! apiHandle)
		return -1;

	// Retrieve section config from api handle
	ctrlConfig = (CtlConfigT *) afb_api_get_userdata(apiHandle);
	if(! ctrlConfig)
		return -2;

	currentHalData = (struct HalData *) getExternalData(ctrlConfig);
	if(! currentHalData)
		return -3;

	// Fill HalDatadata structure
	currentHalData->internal = 1;

	currentHalData->sndCardPath = (char *) ctrlConfig->uid;
	currentHalData->uid = (char *) ctrlConfig->uid;
	currentHalData->info = (char *) ctrlConfig->info;

	currentHalData->author = (char *) ctrlConfig->author;
	currentHalData->version = (char *) ctrlConfig->version;
	currentHalData->date = (char *) ctrlConfig->date;

	currentHalData->internalHalData->apiHandle = apiHandle;
	currentHalData->internalHalData->ctrlConfig = ctrlConfig;

	currentHalData->sndCardId = InternalHalGetCardIdByCardPath(apiHandle, currentHalData->sndCardPath);

	currentHalData->internalHalData->streamUpdates = afb_api_make_event(apiHandle, HAL_STREAM_UPDATES_EVENT_NAME);
	if(! currentHalData->internalHalData->streamUpdates)
		return -4;

	if(currentHalData->sndCardId < 0)
		currentHalData->status = HAL_STATUS_UNAVAILABLE;
	else
		currentHalData->status = HAL_STATUS_AVAILABLE;

	// TBD JAI: handle refresh of hal status for dynamic card (/dev/by-id)

	return CtlConfigExec(apiHandle, ctrlConfig);
}

static int InternalHalLoadOneApi(void *cbdata, afb_api_t apiHandle)
{
	int err;
	CtlConfigT *ctrlConfig;
	CtlSectionT *ctrlCurrentSections;

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

	ctrlConfig = (CtlConfigT*) cbdata;

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

	// Add static internal hal verbs
	if(afb_api_set_verbs_v3(apiHandle, InternalHalApiStaticVerbs)) {
		AFB_API_ERROR(apiHandle, "Load Section : fail to register static V2 verbs");
		return -2;
	}

	ctrlCurrentSections = malloc(sizeof(ctrlSectionsDefault));
	if(! ctrlCurrentSections) {
		AFB_API_ERROR(apiHandle, "Didn't succeed to allocate current internal hal section data structure for controller");
		return -3;
	}

	memcpy(ctrlCurrentSections, ctrlSectionsDefault, sizeof(ctrlSectionsDefault));

	// Load section for corresponding Api
	err = CtlLoadSections(apiHandle, ctrlConfig, ctrlCurrentSections);
	if(err) {
		AFB_API_ERROR(apiHandle, "Didn't succeed to load current internal hal controller section");
		return -4;
	}

	// Declare an event manager for this Api
	afb_api_on_event(apiHandle, InternalHalDispatchApiEvent);

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

	return 0;
}

int InternalHalCreateApi(afb_api_t apiHandle, char *path, struct HalMgrData *halMgrData)
{
	CtlConfigT *ctrlConfig;
	struct HalData *currentHalData;

	if(! apiHandle || ! path || ! halMgrData)
		return -1;

	// Create one Api per file
	ctrlConfig = CtlLoadMetaData(apiHandle, path);
	if(! ctrlConfig) {
		AFB_API_ERROR(apiHandle, "No valid internal hal config file in : '%s'", path);
		return -2;
	}

	if(! ctrlConfig->api) {
		AFB_API_ERROR(apiHandle, "API Missing from metadata in : '%s'", path);
		return -3;
	}

	// Allocation of current internal hal data
	currentHalData = HalUtlAddHalToHalList(&halMgrData->halDataList);
	if(! currentHalData) {
		AFB_API_ERROR(apiHandle, "Didn't succeed to add hal to hal list");
		return -4;
	}

	currentHalData->apiName = (char *) ctrlConfig->api;

	// Stores hal data in controller config
	setExternalData(ctrlConfig, (void *) currentHalData);

	// Allocation of the structure that will be used to store internal hal data
	currentHalData->internalHalData = calloc(1, sizeof(struct InternalHalData));
	if(! currentHalData->internalHalData) {
		AFB_API_ERROR(apiHandle, "Didn't succeed to allocate internal hal data structure");
		return -5;
	}

	// Create one API
	if(! afb_api_new_api(apiHandle, ctrlConfig->api, ctrlConfig->info, 1, InternalHalLoadOneApi, ctrlConfig)) {
		AFB_API_ERROR(apiHandle, "An error occurred at '%s' internal hal api creation", ctrlConfig->api);
		return -6;
	}

	return 0;
}

int InternalHalCreateAllApi(afb_api_t apiHandle, struct HalMgrData *halMgrData)
{
	int index;
	char *dirList, *fileName, *fullPath;
	char filePath[CONTROL_MAXPATH_LEN];

	filePath[CONTROL_MAXPATH_LEN - 1] = '\0';

	json_object *configJ, *entryJ;

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

	AFB_API_NOTICE(apiHandle, "Begining to create all APIs");

	dirList = getenv("CONTROL_CONFIG_PATH");
	if(! dirList)
		dirList = CONTROL_CONFIG_PATH;

	configJ = CtlConfigScan(dirList, "hal");
	if(! configJ) {
		AFB_API_WARNING(apiHandle, "No hal-(binder-middle-name)*.json config file(s) found in %s, 4a-hal-manager will only works with external hal", dirList);
		return 0;
	}

	// We load 1st file others are just warnings
	for(index = 0; index < (int) json_object_array_length(configJ); index++) {
		entryJ = json_object_array_get_idx(configJ, index);

		if(wrap_json_unpack(entryJ, "{s:s, s:s !}", "fullpath", &fullPath, "filename", &fileName)) {
			AFB_API_ERROR(apiHandle, "HOOPs invalid JSON entry = %s", json_object_get_string(entryJ));
			return -2;
		}

		strncpy(filePath, fullPath, sizeof(filePath) - 1);
		strncat(filePath, "/", sizeof(filePath) - 1);
		strncat(filePath, fileName, sizeof(filePath) - 1);

		if(InternalHalCreateApi(apiHandle, filePath, halMgrData) < 0)
			return -3;
	}

	return 0;
}