Detect engine state and use it during diagnostic messages subscriptions

Get engine state recurringly by requesting a permanent
diagnostic messages request.
Use these information to warn that diagnostic request won't have any responses
at the moment of subscription if engine is off.

Bug-AGL: SPEC-1347

Change-Id: If8bd79bba89acd1c8f5452d3efdbf00a89f8cc77
Signed-off-by: Jonathan Aillet <jonathan.aillet@iot.bzh>

3 files changed, 86 insertions, 3 deletions

diff --git a/low-can-binding/binding/application.cpp b/low-can-binding/binding/application.cpp
index 6f2310c1..153821c7 100644
--- a/low-can-binding/binding/application.cpp
+++ b/low-can-binding/binding/application.cpp
@@ -14,12 +14,17 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+#include <ctime>
+
 #include "application.hpp"
 
 #include "../utils/signals.hpp"
 #include "../utils/openxc-utils.hpp"
 #include "low-can-socket.hpp"
 
+#define MICROSECONDS_IN_SECOND	1000000
+#define ENGINE_VALUE_TIMEOUT	5
+
 /// @brief Return singleton instance of configuration object.
 application_t& application_t::instance()
 {
@@ -81,3 +86,54 @@ void application_t::set_active_message_set(uint8_t id)
 {
 	active_message_set_ = id;
 }
+
+bool application_t::isEngineOn()
+{
+	struct utils::signals_found sf;
+	openxc_DynamicField search_key = build_DynamicField("engine.speed");
+	sf = utils::signals_manager_t::instance().find_signals(search_key);
+	bool engine_on = false;
+	uint64_t last_timestamp_in_s;
+
+	if(sf.can_signals.size() == 1)
+	{
+		last_timestamp_in_s = sf.can_signals.front()->get_last_value_with_timestamp().second
+						/ MICROSECONDS_IN_SECOND;
+
+		if(sf.can_signals.front()->get_last_value_with_timestamp().first > 0 &&
+		   std::difftime(std::time(nullptr), last_timestamp_in_s) < ENGINE_VALUE_TIMEOUT)
+		{
+			engine_on = true;
+		}
+		else
+		{
+			AFB_NOTICE("is_engine_on: engine.speed CAN signal found, but engine seems off");
+		}
+	}
+	else
+	{
+		AFB_NOTICE("is_engine_on: Can't identify a useable engine.speed CAN signal");
+	}
+
+	if(sf.diagnostic_messages.size() == 1)
+	{
+		last_timestamp_in_s = sf.diagnostic_messages.front()->get_last_value_with_timestamp().second
+						/ MICROSECONDS_IN_SECOND;
+
+		if(sf.diagnostic_messages.front()->get_last_value_with_timestamp().first > 0 &&
+		   std::difftime(std::time(nullptr), last_timestamp_in_s) < ENGINE_VALUE_TIMEOUT)
+		{
+			engine_on = true;
+		}
+		else
+		{
+			AFB_NOTICE("is_engine_on: engine.speed diagnostic message found, but engine seems off");
+		}
+	}
+	else
+	{
+		AFB_NOTICE("is_engine_on: Can't identify a useable engine.speed diagnostic message");
+	}
+
+	return engine_on;
+}
\ No newline at end of file
diff --git a/low-can-binding/binding/application.hpp b/low-can-binding/binding/application.hpp
index fa2204f0..93494872 100644
--- a/low-can-binding/binding/application.hpp
+++ b/low-can-binding/binding/application.hpp
@@ -78,6 +78,8 @@ class application_t
 
 		uint32_t get_signal_id(can_signal_t& sig) const;
 
+		bool isEngineOn();
+
 		void set_active_message_set(uint8_t id);
 
 /*
diff --git a/low-can-binding/binding/low-can-cb.cpp b/low-can-binding/binding/low-can-cb.cpp
index d8365da0..bff5c935 100644
--- a/low-can-binding/binding/low-can-cb.cpp
+++ b/low-can-binding/binding/low-can-cb.cpp
@@ -210,6 +210,9 @@ static int subscribe_unsubscribe_diagnostic_messages(struct afb_req request,
 		// poll a PID for nothing.
 		if(sig->get_supported() && subscribe)
 		{
+			if (!app.isEngineOn())
+				AFB_WARNING("signal: Engine is off, %s won't received responses until it's on",  sig->get_name().c_str());
+
 			diag_m.add_recurring_request(diag_req, sig->get_name().c_str(), false, sig->get_decoder(), sig->get_callback(), event_filter.frequency, perm_rec_diag_req);
 			if(can_subscription->create_rx_filter(sig) < 0)
 				{return -1;}
@@ -651,6 +654,7 @@ void list(struct afb_req request)
 /// @return Exit code, zero if success.
 int initv2()
 {
+	uint32_t ret = 1;
 	can_bus_t& can_bus_manager = application_t::instance().get_can_bus_manager();
 
 	can_bus_manager.set_can_devices();
@@ -660,8 +664,29 @@ int initv2()
 	/// We pass by default the first CAN bus device to its Initialization.
 	/// TODO: be able to choose the CAN bus device that will be use as Diagnostic bus.
 	if(application_t::instance().get_diagnostic_manager().initialize())
-		return 0;
+		ret = 0;
+
+	// Add a recurring dignostic message request to get engine speed continuously
+	openxc_DynamicField search_key = build_DynamicField("diagnostic_messages.engine.speed");
+	struct utils::signals_found sf = utils::signals_manager_t::instance().find_signals(search_key);
+
+	if(sf.can_signals.empty() && sf.diagnostic_messages.size() == 1)
+	{
+		struct afb_req request;
+		request.itf = nullptr;
+		request.closure = nullptr;
+
+		struct event_filter_t event_filter;
+		event_filter.frequency = sf.diagnostic_messages.front()->get_frequency();
 
-	AFB_ERROR("There was something wrong with CAN device Initialization.");
-	return 1;
+		utils::signals_manager_t& sm = utils::signals_manager_t::instance();
+		std::map<int, std::shared_ptr<low_can_subscription_t> >& s = sm.get_subscribed_signals();
+
+		subscribe_unsubscribe_diagnostic_messages(request, true, sf.diagnostic_messages, event_filter, s, true);
+	}
+
+	if(ret)
+		AFB_ERROR("There was something wrong with CAN device Initialization.");
+
+	return ret;
 }