Change, clean plugins.

Improve GPS plugin to be able to calculate the heading also remove
the builtin plugin that was an error. We need to pass GPS plugin in
C++ to be able to use the context.

Handle "double" and "int" signal's value.

Change-Id: I6d902e4ac76a0e933326c0b4c43922645c9c5a4c
Signed-off-by: Romain Forlot <romain.forlot@iot.bzh>

6 files changed, 93 insertions, 150 deletions

diff --git a/docs/part-1/3-Plugins.md b/docs/part-1/3-Plugins.md
index 50ece7b..b58bbad 100644
--- a/docs/part-1/3-Plugins.md
+++ b/docs/part-1/3-Plugins.md
@@ -1,15 +1,23 @@
 # Plugins
 
-Plugins are C/C++ shared library loaded by the binding to execute some
+Plugins are C/C++ shared libraries loaded by the binding to execute some
 simple routine. Routine could be on reception of a new signal or at sources
 initialization time or signal subscription with the respective JSON field
-**onReceived**, **init** and **getSignals**.
+`onReceived` `init` and `getSignals`
 
 A default plugin (builtin) is provided with 2 functions:
 
 - **defaultOnReceived**: set and record a new signal value and its timestamp
  in the signal composer service. It simply tooks the incoming event JSON object
- and search for *key* **value** and **timestamp** then call function
+ and search for *key* `value` and `timestamp` then call function
  `setSignalValue`.
-- **setSignalValueWrap**: a **lua2c** function the could be called from any LUA
+- **setSignalValueWrap**: a `lua2c` function the could be called from any LUA
  script to record a new signal value.
+
+> **CAUTION**: `timestamp` value has to be typed as *uint64_t* with
+> a **nanosecond** precision using a realtime clock. To correctly store it in
+> a JSON-C object use the int64 type with the according fonctions:
+> *json_object_new_int64()*
+> *json_object_get_int64()*
+> *json_object_set_int64()*
+> *...*
diff --git a/plugins/CMakeLists.txt b/plugins/CMakeLists.txt
index b6eec08..0d437d5 100644
--- a/plugins/CMakeLists.txt
+++ b/plugins/CMakeLists.txt
@@ -63,7 +63,7 @@ PROJECT_TARGET_ADD(low-can)
 PROJECT_TARGET_ADD(gps)
 
 	# Define targets
-	ADD_LIBRARY(${TARGET_NAME} MODULE ${TARGET_NAME}.c)
+	ADD_LIBRARY(${TARGET_NAME} MODULE ${TARGET_NAME}.cpp)
 
 	# Alsa Plugin properties
 	SET_TARGET_PROPERTIES(${TARGET_NAME} PROPERTIES
diff --git a/plugins/builtin.cpp b/plugins/builtin.cpp
deleted file mode 100644
index 5eccc24..0000000
--- a/plugins/builtin.cpp
+++ /dev/null
@@ -1,83 +0,0 @@
-/*
- * Copyright (C) 2016 "IoT.bzh"
- * Author Romain Forlot <romain.forlot@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 AFB_BINDING_VERSION 2
-#include <afb/afb-binding.h>
-#include <systemd/sd-event.h>
-#include <json-c/json_object.h>
-#include <stdbool.h>
-#include <string.h>
-
-#include "signal-composer.hpp"
-#include "wrap-json.h"
-
-extern "C"
-{
-CTLP_LUA_REGISTER("builtin");
-
-CTLP_CAPI (defaultOnReceived, source, argsJ, eventJ)
-{
-	struct signalCBT* ctx = (struct signalCBT*)source->context;
-	AFB_NOTICE("source: %s argj: %s, eventJ %s", source->uid,
-		json_object_to_json_string(argsJ),
-		json_object_to_json_string(eventJ));
-
-	json_object* valueJ = nullptr;
-	json_object* timestampJ = nullptr;
-	double value = 0;
-	uint64_t timestamp = 0;
-	if(json_object_object_get_ex(eventJ, "value", &valueJ))
-		{value = json_object_get_double(valueJ);}
-	if(json_object_object_get_ex(eventJ, "timestamp", &timestampJ))
-		{timestamp = json_object_get_int64(timestampJ);}
-
-	struct signalValue v = value;
-	ctx->setSignalValue(ctx->aSignal, timestamp, v);
-	return 0;
-}
-
-CTLP_LUA2C (setSignalValueWrap, source, argsJ, responseJ)
-{
-	const char* name = nullptr;
-	double resultNum;
-	uint64_t timestamp;
-
-	struct signalCBT* ctx = (struct signalCBT*)source->context;
-
-	if(! wrap_json_unpack(argsJ, "{ss, sF, sI? !}",
-		"name", &name,
-		"value", &resultNum,
-		"timestamp", &timestamp))
-	{
-		*responseJ = json_object_new_string("Fail to unpack JSON arguments value");
-		return -1;
-	}
-	*responseJ = json_object_new_string(json_object_to_json_string(argsJ));
-
-	struct signalValue result = resultNum;
-
-	if(ctx->aSignal)
-		{ctx->setSignalValue(ctx->aSignal, timestamp*MICRO, result);}
-	else
-		{ctx->searchNsetSignalValue(name, timestamp*MICRO, result);}
-
-	return 0;
-}
-
-// extern "C" closure
-}
diff --git a/plugins/gps.c b/plugins/gps.c
deleted file mode 100644
index af594fa..0000000
--- a/plugins/gps.c
+++ /dev/null
@@ -1,54 +0,0 @@
-/*
- * Copyright (C) 2016 "IoT.bzh"
- * Author Romain Forlot <romain.forlot@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  // needed for vasprintf
-
-#define AFB_BINDING_VERSION 2
-#include <afb/afb-binding.h>
-#include <systemd/sd-event.h>
-#include <json-c/json_object.h>
-#include <stdbool.h>
-#include <string.h>
-
-#include "ctl-plugin.h"
-#include "wrap-json.h"
-
-CTLP_CAPI_REGISTER("gps");
-
-// Call at initialisation time
-/*CTLP_ONLOAD(plugin, api) {
-	AFB_NOTICE ("GPS plugin: uid='%s' 'info='%s'", plugin->uid, plugin->info);
-	return api;
-}*/
-
-CTLP_CAPI (subscribeToLow, source, argsJ, eventJ) {
-	json_object* subscribeArgsJ = NULL, *responseJ = NULL;
-
-	int err = 0;
-	wrap_json_pack(&subscribeArgsJ, "{ss}", "value", "location");
-
-	AFB_DEBUG("Calling subscribe with %s", json_object_to_json_string_ext(subscribeArgsJ, JSON_C_TO_STRING_PRETTY));
-	err = afb_service_call_sync("gps", "subscribe", subscribeArgsJ, &responseJ);
-	if(err)
-	{
-		AFB_ERROR("Can't find api 'gpsd'");
-		return err;
-	}
-
-	return err;
-}
diff --git a/plugins/gps.cpp b/plugins/gps.cpp
new file mode 100644
index 0000000..60aa80a
--- /dev/null
+++ b/plugins/gps.cpp
@@ -0,0 +1,70 @@
+/*
+ * Copyright (C) 2016 "IoT.bzh"
+ * Author Romain Forlot <romain.forlot@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 CTL_PLUGIN_MAGIC 1286576532
+
+#define AFB_BINDING_VERSION 2
+#include <afb/afb-binding.h>
+#include <systemd/sd-event.h>
+#include <json-c/json_object.h>
+#include <math.h>
+
+#include "signal-composer.hpp"
+
+extern "C"
+{
+CTLP_CAPI_REGISTER("gps");
+
+CTLP_CAPI (getHeading, source, argsJ, eventJ) {
+
+	static bool coordUpdated = true;
+	static double prvLat = 0, prvLon = 0, curLat = 0, curLon = 0, heading = 0;
+	double r2d =  180.0 / M_PI;
+	double d2r = M_PI / 180.0;
+	int err = 0;
+
+	struct signalCBT* ctx = (struct signalCBT*)source->context;
+	json_object *val = NULL, *lastSignal = NULL, *id = NULL;
+
+	lastSignal = json_object_array_get_idx(eventJ, json_object_array_length(eventJ) -1);
+
+	if(json_object_object_get_ex(lastSignal, "uid", &id) && std::string(json_object_get_string(id)) == "latitude" &&
+		json_object_object_get_ex(lastSignal, "value", &val)) {
+			prvLat = curLat;
+			curLat = json_object_get_double(val);
+			coordUpdated = !coordUpdated;
+	}
+
+	if(json_object_object_get_ex(lastSignal, "uid", &id) &&
+	std::string(json_object_get_string(id)) == "longitude" &&
+	json_object_object_get_ex(lastSignal, "value", &val)) {
+		prvLon = curLon;
+		curLon = json_object_get_double(val);
+		coordUpdated = !coordUpdated;
+	}
+
+	if(coordUpdated) {
+		heading = round(r2d * atan2((curLon - prvLon) * cos(d2r * curLat), curLat - prvLat));
+		ctx->setSignalValue(ctx->aSignal, 0, heading);
+	}
+
+	AFB_NOTICE("======== Heading: %f", heading);
+	return err;
+}
+// extern "C" closure
+}
diff --git a/signal-composer-binding/signal.cpp b/signal-composer-binding/signal.cpp
index 3a448b1..ecba162 100644
--- a/signal-composer-binding/signal.cpp
+++ b/signal-composer-binding/signal.cpp
@@ -281,25 +281,27 @@ void Signal::defaultReceivedCB(json_object *eventJ)
 		if (key.find("value") != std::string::npos ||
 			key.find(id_) != std::string::npos)
 		{
-			switch(json_object_get_type(value)) {
-				case json_type_double: {
+			switch (json_object_get_type(value)) {
+				case json_type_double:
 					sv = json_object_get_double(value);
 					break;
-				}
-				case json_type_boolean: {
+				case json_type_int:
 					sv = json_object_get_int(value);
 					break;
-				}
-				case json_type_string: {
+				case json_type_boolean:
+					sv = json_object_get_int(value);
+					break;
+				case json_type_string:
 					sv = json_object_get_string(value);
 					break;
-				}
+				default:
+					sv = signalValue();
+					break;
 			}
 		}
 		else if (key.find("timestamp") != std::string::npos)
 		{
 			ts = json_object_is_type(value, json_type_int) ? json_object_get_int64(value):ts;
-			ts = json_object_is_type(value, json_type_double) ? (uint64_t)json_object_get_double(value) * NANO : ts;
 		}
 		json_object_iter_next(&iter);
 	}