Be able to write raw frame & encode value to sent

Check whether the argument is a raw frame or a Signal + Value
to encode then send.
1 new class to handle encoding part of a value as well as
a new method for can_signal_t which return index of a map from
its value.

Change-Id: I288d2aeec28ce74c9ca35750db18557c9251e1df
Signed-off-by: Romain Forlot <romain.forlot@iot.bzh>

6 files changed, 272 insertions, 30 deletions

diff --git a/low-can-binding/CMakeLists.txt b/low-can-binding/CMakeLists.txt
index fd68e6c..44ae9ef 100644
--- a/low-can-binding/CMakeLists.txt
+++ b/low-can-binding/CMakeLists.txt
@@ -34,6 +34,7 @@ PROJECT_TARGET_ADD(low-can)
 		can/can-message.cpp
 		can/can-signals.cpp
 		can/can-decoder.cpp
+		can/can-encoder.cpp
 		diagnostic/diagnostic-message.cpp
 		diagnostic/diagnostic-manager.cpp
 		diagnostic/active-diagnostic-request.cpp
diff --git a/low-can-binding/binding/low-can-cb.cpp b/low-can-binding/binding/low-can-cb.cpp
index a7e4396..5910f6a 100644
--- a/low-can-binding/binding/low-can-cb.cpp
+++ b/low-can-binding/binding/low-can-cb.cpp
@@ -28,6 +28,7 @@
 
 #include "openxc.pb.h"
 #include "application.hpp"
+#include "../can/can-encoder.hpp"
 #include "../can/can-bus.hpp"
 #include "../can/can-signals.hpp"
 #include "../can/can-message.hpp"
@@ -372,54 +373,87 @@ void swrite(struct afb_req request)
 	int rc = 0;
 	struct can_frame cf;
 	struct utils::signals_found sf;
-	struct json_object *args, *json_can_socket, *json_can_id, *json_can_dlc, *json_can_data;
+	struct json_object* args = nullptr,
+		*json_name = nullptr,
+		*json_value = nullptr;
+	std::map<std::string, std::shared_ptr<low_can_socket_t> >& cd = application_t::instance().get_can_devices();
 
 	::memset(&cf, 0, sizeof(cf));
 
 	args = afb_req_json(request);
-	if (args == NULL || (
-		((!json_object_object_get_ex(args, "canbus_name", &json_can_socket)) && json_object_get_type(json_can_socket) == json_type_string) &&
-		((!json_object_object_get_ex(args, "can_id", &json_can_id)) && json_object_get_type(json_can_id) == json_type_int) &&
-		((!json_object_object_get_ex(args, "can_dlc", &json_can_dlc)) && json_object_get_type(json_can_dlc) == json_type_int)))
-	{
-		cf.can_id = json_object_get_int(json_can_id);
-		cf.can_dlc = (uint8_t)json_object_get_int(json_can_dlc);
-		openxc_DynamicField search_key = build_DynamicField((double)cf.can_id);
-		sf = utils::signals_manager_t::instance().find_signals(search_key);
-	}
 
-	if((args == NULL || !json_object_object_get_ex(args, "can_data", &json_can_data)) && json_object_get_type(json_can_data) == json_type_array)
+	// Process about Raw CAN message on CAN bus directly
+	if (args != NULL &&
+		(json_object_object_get_ex(args, "bus_name", &json_name) && json_object_is_type(json_name, json_type_string) ) &&
+		(json_object_object_get_ex(args, "frame", &json_value) && json_object_is_type(json_value, json_type_object) ))
 	{
-		struct json_object *x;
+		struct json_object* json_can_id = nullptr,
+			*json_can_dlc = nullptr,
+			*json_can_data = nullptr;
 
-		int n = json_object_array_length(json_can_data);
-		if(n < 8)
+		if( (json_object_object_get_ex(json_value, "can_id", &json_can_id) && (json_object_is_type(json_can_id, json_type_double) || json_object_is_type(json_can_id, json_type_int))) &&
+			(json_object_object_get_ex(json_value, "can_dlc", &json_can_dlc) && (json_object_is_type(json_can_dlc, json_type_double) || json_object_is_type(json_can_dlc, json_type_int))) &&
+			(json_object_object_get_ex(json_value, "can_data", &json_can_data) && json_object_is_type(json_can_data, json_type_array) ))
 		{
-			for (int i = 0 ; i < n ; i++)
+			cf.can_id = json_object_get_int(json_can_id);
+			cf.can_dlc = (uint8_t)json_object_get_int(json_can_dlc);
+
+			struct json_object *x;
+			int n = json_object_array_length(json_can_data);
+			if(n <= 8)
 			{
-				x = json_object_array_get_idx(json_can_data, i);
-				cf.data[i] = json_object_get_type(x) == json_type_int ? (uint8_t)json_object_get_int(x) : 0;
+				for (int i = 0 ; i < n ; i++)
+				{
+					x = json_object_array_get_idx(json_can_data, i);
+					cf.data[i] = json_object_get_type(x) == json_type_int ? (uint8_t)json_object_get_int(x) : 0;
+				}
 			}
-		}
-	}
 
-	if (sf.can_signals.empty() && sf.diagnostic_messages.empty())
-	{
-		AFB_WARNING("No signal(s) found for id %d. Message not sent.", cf.can_id);
-		rc = -1;
+			const std::string bus_name = json_object_get_string(json_name);
+			const std::string found_device = application_t::instance().get_can_bus_manager().get_can_device_name(bus_name);
+			if( ! found_device.empty())
+			{
+				if( cd.count(bus_name) == 0)
+					{cd[bus_name] = std::make_shared<low_can_socket_t>(low_can_socket_t());}
+				rc = cd[bus_name]->tx_send(cf, found_device);
+			}
+		}
+		else
+		{
+			AFB_ERROR("Frame object malformed (must be \n \"frame\": {\"can_id\": int, \"can_dlc\": int, \"can_data\": [ int, int , int, int ,int , int ,int ,int]}");
+			rc = -1;
+		}
 	}
-	else
+	// Search signal then encode value.
+	else if(args != NULL &&
+		(json_object_object_get_ex(args, "signal_name", &json_name) && json_object_is_type(json_name, json_type_string)) &&
+		(json_object_object_get_ex(args, "signal_value", &json_value) && (json_object_is_type(json_value, json_type_double) || json_object_is_type(json_value, json_type_int))))
 	{
-		std::map<std::string, std::shared_ptr<low_can_socket_t> >& cd = application_t::instance().get_can_devices();
-		const char* can_socket = json_object_get_string(json_can_socket);
-		for(const auto& sig: sf.can_signals)
+		openxc_DynamicField search_key = build_DynamicField(json_object_get_string(json_name));
+		sf = utils::signals_manager_t::instance().find_signals(search_key);
+
+		if (sf.can_signals.empty())
+		{
+			AFB_WARNING("No signal(s) found for id %d. Message not sent.", cf.can_id);
+			rc = -1;
+		}
+		else
 		{
-			if (sig->get_message()->get_bus_name().c_str() == can_socket)
+			for(const auto& sig: sf.can_signals)
 			{
-				rc = cd[can_socket]->tx_send(cf, sig);
+				cf = encoder_t::build_frame(sig, (uint64_t)json_object_get_double(json_value));
+				const std::string bus_name = sig->get_message()->get_bus_name();
+				if( cd.count(bus_name) == 0)
+					{cd[bus_name] = std::make_shared<low_can_socket_t>(low_can_socket_t());}
+				rc = cd[bus_name]->tx_send(cf, sig);
 			}
 		}
 	}
+	else
+	{
+		AFB_ERROR("Request argument malformed. Please use the following syntax:");
+		rc = -1;
+	}
 
 	if (rc >= 0)
 		afb_req_success(request, NULL, NULL);
diff --git a/low-can-binding/can/can-encoder.cpp b/low-can-binding/can/can-encoder.cpp
new file mode 100644
index 0000000..b87407f
--- /dev/null
+++ b/low-can-binding/can/can-encoder.cpp
@@ -0,0 +1,159 @@
+/*
+ * Copyright (C) 2015, 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.
+ */
+
+#include "can-encoder.hpp"
+
+#include "canutil/write.h"
+#include "../utils/openxc-utils.hpp"
+#include "can-message-definition.hpp"
+#include "../binding/low-can-hat.hpp"
+
+/// @brief Write a value into a CAN signal in the destination buffer.
+///
+/// @param[in] signal - The CAN signal to write, including the bit position and bit size.
+/// @param[in] value - The encoded integer value to write into the CAN signal.
+/// @param[out] data - The destination buffer.
+/// @param[in] length - The length of the destination buffer.
+///
+/// @return Returns a can_frame struct initialized and ready to be send.
+const can_frame build_frame(const can_signal_t& signal, uint64_t value)
+{
+	struct can_frame cf;
+	::memset(&cf, 0, sizeof(cf));
+
+	cf.can_id = signal.get_message()->get_id();
+	cf.can_dlc = CAN_MAX_DLEN;
+	bitfield_encode_float((float)value,
+						signal.get_bit_position(),
+						signal.get_bit_size(),
+						signal.get_factor(),
+						signal.get_offset(),
+						cf.data,
+						CAN_MAX_DLEN);
+
+	return cf;
+}
+
+/// @brief Encode a boolean into an integer, fit for a CAN signal bitfield.
+///
+/// This is a shortcut for encodeDynamicField(CanSignal*, openxc_DynamicField*,
+/// bool*) that takes care of creating the DynamicField object for you with the
+/// boolean value.
+///
+/// @param[in] signal  - The CAN signal to encode this value for..
+/// @param[in] value - The boolean value to encode
+/// @param[out] send - An output argument that will be set to false if the value should
+///     not be sent for any reason.
+///
+/// @return Returns the encoded integer. If 'send' is changed to false, the field could
+/// not be encoded and the return value is undefined.
+///
+uint64_t encoder_t::encode_boolean(const can_signal_t& signal, bool value, bool* send)
+{
+	return encode_number(signal, float(value), send);
+}
+/// @brief Encode a float into an integer, fit for a CAN signal's bitfield.
+///
+/// This is a shortcut for encodeDynamicField(CanSignal*, openxc_DynamicField*,
+/// bool*) that takes care of creating the DynamicField object for you with the
+/// float value.
+///
+/// @param[in] signal  - The CAN signal to encode this value for.
+/// @param[in] value - The float value to encode.
+/// @param[out] send - This output argument will always be set to false, so the caller will
+///      know not to publish this value to the pipeline.
+///
+/// @return Returns the encoded integer. If 'send' is changed to false, the field could
+/// not be encoded and the return value is undefined.
+///
+uint64_t encoder_t::encode_number(const can_signal_t& signal, float value, bool* send)
+{
+	return float_to_fixed_point(value, signal.get_factor(), signal.get_offset());
+}
+
+/// @brief Encode a string into an integer, fit for a CAN signal's bitfield.
+///
+/// Be aware that the behavior is undefined if there are multiple values assigned
+/// to a single state. See https://github.com/openxc/vi-firmware/issues/185.
+///
+/// This is a shortcut for encodeDynamicField(CanSignal*, openxc_DynamicField*,
+/// bool*) that takes care of creating the DynamicField object for you with the
+/// string state value.
+///
+/// @param[in] signal  - The details of the signal that contains the state mapping.
+/// @param[in] value - The string state value to encode.
+/// @param[out] send - An output argument that will be set to false if the value should
+///     not be sent for any reason.
+///
+/// @return Returns the encoded integer. If 'send' is changed to false, the field could
+/// not be encoded and the return value is undefined.
+///
+uint64_t encoder_t::encode_state(const can_signal_t& signal, const std::string& state, bool* send)
+{
+	uint64_t value = 0;
+	if(state == "")
+	{
+		AFB_DEBUG("Can't write state of "" -- not sending");
+		*send = false;
+	}
+	else
+	{
+		uint64_t signal_state = signal.get_states(state);
+		if(signal_state != -1) {
+			value = signal_state;
+		} else {
+			AFB_DEBUG("Couldn't find a valid signal state for %s", state.c_str());
+			*send = false;
+		}
+	}
+	return value;
+}
+
+/// @brief Parse a signal from a CAN message and apply any required
+/// transforations to get a human readable value.
+///
+/// If the can_signal_t has a non-NULL 'decoder' field, the raw CAN signal value
+/// will be passed to the decoder before returning.
+///
+/// @param[in] signal - The details of the signal to decode and forward.
+/// @param[in] value - The numerical value that will be converted to a boolean.
+/// @param[out] send - An output parameter that will be flipped to false if the value could
+///      not be decoded.
+///
+/// @return The decoder returns an openxc_DynamicField, which may contain a number,
+/// string or boolean. If 'send' is false, the return value is undefined.
+///
+uint64_t encoder_t::encode_DynamicField( can_signal_t& signal, const openxc_DynamicField& field, bool* send)
+{
+	uint64_t value = 0;
+	switch(field.type) {
+		case openxc_DynamicField_Type_STRING:
+			value = encode_state(signal, field.string_value, send);
+			break;
+		case openxc_DynamicField_Type_NUM:
+			value = encode_number(signal, (float)field.numeric_value, send);
+			break;
+		case openxc_DynamicField_Type_BOOL:
+			value = encode_boolean(signal, field.boolean_value, send);
+			break;
+		default:
+			AFB_DEBUG("Dynamic field didn't have a value, can't encode");
+			*send = false;
+			break;
+	}
+	return value;
+}
diff --git a/low-can-binding/can/can-encoder.hpp b/low-can-binding/can/can-encoder.hpp
new file mode 100644
index 0000000..f7e8394
--- /dev/null
+++ b/low-can-binding/can/can-encoder.hpp
@@ -0,0 +1,33 @@
+/*
+ * Copyright (C) 2015, 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.
+ */
+
+#pragma once
+
+#include "can-signals.hpp"
+#include "can-message.hpp"
+#include "openxc.pb.h"
+
+class encoder_t
+{
+public:
+	static const can_frame build_frame(const can_signal_t& signal, uint64_t value);
+	static uint64_t encode_state(const can_signal_t& signal, const std::string& value, bool* send);
+	static uint64_t encode_boolean(const can_signal_t& signal, bool value, bool* send);
+	static uint64_t encode_number(const can_signal_t& signal, float value, bool* send);
+
+	static uint64_t encode_DynamicField(can_signal_t& signal, const openxc_DynamicField& field, bool* send);
+};
diff --git a/low-can-binding/can/can-signals.cpp b/low-can-binding/can/can-signals.cpp
index 573808a..45c54cb 100644
--- a/low-can-binding/can/can-signals.cpp
+++ b/low-can-binding/can/can-signals.cpp
@@ -141,6 +141,20 @@ const std::string can_signal_t::get_states(uint8_t value)
 	return std::string();
 }
 
+uint64_t can_signal_t::get_states(const std::string& value) const
+{
+	uint64_t ret = -1;
+	for( const auto& state: states_)
+	{
+		if(state.second == value)
+		{
+			ret = (uint64_t)state.first;
+			break;
+		}
+	}
+	return ret;
+}
+
 size_t can_signal_t::get_state_count() const
 {
 	return states_.size();
diff --git a/low-can-binding/can/can-signals.hpp b/low-can-binding/can/can-signals.hpp
index f7ff037..1b27622 100644
--- a/low-can-binding/can/can-signals.hpp
+++ b/low-can-binding/can/can-signals.hpp
@@ -133,6 +133,7 @@ public:
 	bool get_force_send_changed() const;
 	const std::map<uint8_t, std::string>& get_states() const;
 	const std::string get_states(uint8_t value);
+	uint64_t get_states(const std::string& value) const;
 	size_t get_state_count() const;
 	bool get_writable() const;
 	signal_decoder& get_decoder();