fixup! defining MqttClient classes

Author: andreagilardoni

api/net/MqttClient.cpp

@@ -1,48 +1,83 @@
 #include "MqttClient.h"
+#include <Arduino.h>
+
+std::function<std::unique_ptr<MqttClientInterface>()>* MqttClient::_factory = nullptr;
+
+
+MqttClient::MqttClient()
+: impl(nullptr) {
+
+}
 
 //TODO define constant value for pimpl not instantiated
 int MqttClient::connect(IPAddress ip, uint16_t port) {
     return impl != nullptr? impl->connect(ip, port) : -1;
 }
 
 int MqttClient::connect(const char *host, uint16_t port) {
+    checkInstance();
     return impl != nullptr? impl->connect(host, port) : -1;
 }
 
 void MqttClient::disconnect() {
+    checkInstance();
     if(impl != nullptr) {
-        return impl->disconnect();
+        impl->disconnect();
     }
 }
 
 uint8_t MqttClient::connected() {
+    checkInstance();
     return impl != nullptr? impl->connected() : 0;
 }
 
 MqttClient::operator bool() {
-    // FIXME
+    checkInstance();
+    // FIXME check operator bool call works
     return impl != nullptr? impl->operator bool() : false;
 }
 
 error_t MqttClient::subscribe(Topic t, MqttQos qos) {
+    checkInstance();
     return impl != nullptr? impl->subscribe(t, qos) : -1;
 }
 
 error_t MqttClient::publish(Topic t, uint8_t payload[], size_t size, MqttQos qos) {
+    checkInstance();
     return impl != nullptr? impl->publish(t, payload, size, qos) : -1;
 }
 
 error_t MqttClient::unsubscribe(Topic t) {
+    checkInstance();
     return impl != nullptr? impl->unsubscribe(t) : -1;
 }
 
 void MqttClient::poll() {
+    checkInstance();
     if(impl != nullptr) {
         return impl->poll();
     }
 }
 
 error_t MqttClient::ping() {
+    checkInstance();
     return impl != nullptr? impl->ping() : -1;
 }
 
+// TODO call impl set client id when instantiating the implementation
+void MqttClient::setClientId(char* client_id)  {
+    MqttClientInterface::setClientId(client_id);
+    if(impl != nullptr) {
+        impl->setClientId(client_id);
+    }
+}
+
+void MqttClient::checkInstance() {
+    if(impl == nullptr && _factory != nullptr) {
+        impl = _factory->operator()();
+
+        // if client id has been set before the implementation has been instantiated
+        // set it in the implementation
+        impl->setClientId(_clientid);
+    }
+}

api/net/MqttClient.h

@@ -33,6 +33,8 @@ enum MqttQos: uint8_t {
 constexpr MqttQos QosDefault = MqttQos0;
 constexpr size_t MqttClientIdMaxLength = 256;
 
+// TODO make it possible to generate the client id if none is provided during connect
+//      + should it be performed by the derived class or by the interface?
 class MqttClientInterface: public arduino::ClientConnect{
 public:
     // virtual ~MqttClientInterface() = default; // not needed if deriving from ClientConnect
@@ -49,18 +51,16 @@ class MqttClientInterface: public arduino::ClientConnect{
 
     // nullptr means generate it randomly
     // TODO should this be pure virtual?
-    virtual void setClientId(const char* const clientid = nullptr) { // TODO put this in .cpp file
-        if(clientid == nullptr) {
-            // TODO generate it randomly
-        } else {
-            strncpy(_clientid, clientid, MqttClientIdMaxLength);
-        }
+    virtual void setClientId(char* client_id = nullptr) { // TODO put this in .cpp file
+        _clientid = client_id;
     }
 
     // TODO Will stuff
     // TODO auth stuff, also related to MQTT 5.0
 protected:
-    char _clientid[MqttClientIdMaxLength+1];
+    // TODO is it better to use the one provided from outside or copy it locally?
+    char* _clientid;
+    // char _clientid[MqttClientIdMaxLength+1];
 
     // TODO single callback for every incoming message or a callback for everything?
     MqttReceiveCallback _cbk;
@@ -70,6 +70,7 @@ class MqttClientInterface: public arduino::ClientConnect{
 // this could be generally available, outside of namespaces
 class MqttClient: public MqttClientInterface {
 public:
+    MqttClient();
 
     int connect(IPAddress ip, uint16_t port) override;
     int connect(const char *host, uint16_t port) override;
@@ -86,12 +87,18 @@ class MqttClient: public MqttClientInterface {
     error_t ping() override;
 
     static void setFactory(std::function<std::unique_ptr<MqttClientInterface>()> factory) {
-        _factory = factory;
+        // FIXME find a better way to solve constructor call order
+        static std::function<std::unique_ptr<MqttClientInterface>()> f = factory;
+        _factory = &f;
     }
+
+    void setClientId(char* client_id = nullptr) override;
 protected:
-    static std::function<std::unique_ptr<MqttClientInterface>()> _factory;
+    static std::function<std::unique_ptr<MqttClientInterface>()> *_factory;
 
     std::unique_ptr<MqttClientInterface> impl;
+private:
+    inline void checkInstance();
 };
 
 // } // }}