HASwitch improvements

src/device-types/HASwitch.cpp

@@ -34,7 +34,7 @@ void HASwitch::onMqttConnected()
     }
 
     publishConfig();
-    publishCurrentState();
+    publishState(_currentState);
     subscribeCommandTopic();
 }
 
@@ -44,7 +44,9 @@ void HASwitch::onMqttMessage(
     const uint16_t& length
 )
 {
-    // todo: find a faster way of topic's verification
+    if (strlen(_name) == 0) {
+        return;
+    }
 
     static const char Slash[] PROGMEM = {"/"};
     uint8_t suffixLength = strlen(_name) + strlen(CommandTopic) + 3; // two slashes + null terminator
@@ -61,35 +63,27 @@ void HASwitch::onMqttMessage(
     }
 }
 
-void HASwitch::setState(bool state)
+bool HASwitch::setState(bool state)
 {
-    if (state) {
-        turnOn();
-    } else {
-        turnOff();
+    if (_currentState == state) {
+        return true;
     }
-}
 
-void HASwitch::turnOn()
-{
-    _currentState = true;
-    triggerCallback(_currentState);
-    publishCurrentState();
-}
+    if (strlen(_name) == 0) {
+        return false;
+    }
 
-void HASwitch::turnOff()
-{
-    _currentState = false;
-    triggerCallback(_currentState);
-    publishCurrentState();
+    if (publishState(state)) {
+        _currentState = state;
+        triggerCallback(_currentState);
+        return true;
+    }
+
+    return false;
 }
 
 void HASwitch::onStateChanged(HASWITCH_CALLBACK)
 {
-    if (_stateCallback != nullptr) {
-        return; // only one callback may be assigned to the switch
-    }
-
     _stateCallback = callback;
 }
 
@@ -139,10 +133,10 @@ void HASwitch::publishConfig()
     }
 }
 
-void HASwitch::publishCurrentState()
+bool HASwitch::publishState(bool state)
 {
     if (strlen(_name) == 0) {
-        return;
+        return false;
     }
 
     const uint16_t& topicSize = calculateTopicLength(
@@ -151,7 +145,7 @@ void HASwitch::publishCurrentState()
         StateTopic
     );
     if (topicSize == 0) {
-        return;
+        return false;
     }
 
     char topic[topicSize];
@@ -163,10 +157,10 @@ void HASwitch::publishCurrentState()
     );
 
     if (strlen(topic) == 0) {
-        return;
+        return false;
     }
 
-    mqtt()->publish(topic, (_currentState ? StateOn : StateOff), true);
+    return mqtt()->publish(topic, (state ? StateOn : StateOff), true);
 }
 
 void HASwitch::subscribeCommandTopic()
@@ -225,21 +219,21 @@ uint16_t HASwitch::calculateSerializedLength(const char* serializedDevice) const
         strlen(_name) + 10; // 10 - length of the JSON data for this field
 
     // unique ID
-    if (serializedDevice == nullptr) {
-        size += strlen(_name) + 13; // 13 - length of the JSON data for this field
-    } else {
-        size += strlen(mqtt()->getDevice()->getUniqueId());
-        size += strlen(_name) + 14; // 14 - length of the JSON data for this field
+    size += strlen(mqtt()->getDevice()->getUniqueId());
+    size += strlen(_name) + 14; // 14 - length of the JSON data for this field
 
-        // device
-        size += strlen(serializedDevice) + 7; // 7 - length of the JSON data for this field
-    }
+    // device
+    size += strlen(serializedDevice) + 7; // 7 - length of the JSON data for this field
 
     return size;
 }
 
 bool HASwitch::writeSerializedTrigger(const char* serializedDevice) const
 {
+    if (serializedDevice == nullptr) {
+        return false;
+    }
+
     static const char QuotationSign[] PROGMEM = {"\""};
 
     // command topic
@@ -313,30 +307,23 @@ bool HASwitch::writeSerializedTrigger(const char* serializedDevice) const
 
     // unique ID
     {
+        static const char Underscore[] PROGMEM = {"_"};
         static const char DataBefore[] PROGMEM = {",\"uniq_id\":\""};
+
         const HADevice* device = mqtt()->getDevice();
+        uint8_t uniqueIdLength = strlen(_name) + strlen(device->getUniqueId()) + 2; // underscore and null temrinator
+        char uniqueId[uniqueIdLength];
+        strcpy(uniqueId, _name);
+        strcat_P(uniqueId, Underscore);
+        strcat(uniqueId, device->getUniqueId());
 
         mqtt()->writePayload_P(DataBefore);
-
-        if (device == nullptr) {
-            mqtt()->writePayload(_name, strlen(_name));
-        } else {
-            static const char Underscore[] PROGMEM = {"_"};
-
-            uint8_t uniqueIdLength = strlen(_name) + strlen(device->getUniqueId()) + 2; // underscore and null temrinator
-            char uniqueId[uniqueIdLength];
-            strcpy(uniqueId, _name);
-            strcat_P(uniqueId, Underscore);
-            strcat(uniqueId, device->getUniqueId());
-
-            mqtt()->writePayload(uniqueId, strlen(uniqueId));
-        }
-
+        mqtt()->writePayload(uniqueId, strlen(uniqueId));
         mqtt()->writePayload_P(QuotationSign);
     }
 
     // device
-    if (serializedDevice != nullptr) {
+    {
         static const char Data[] PROGMEM = {",\"dev\":"};
 
         mqtt()->writePayload_P(Data);

src/device-types/HASwitch.h

@@ -9,6 +9,13 @@
 class HASwitch : public BaseDeviceType
 {
 public:
+    /**
+     * Initializes switch.
+     *
+     * @param name Name of the switch. Recommendes characters: [a-z0-9\-_]
+     * @param initialState Initial state of the switch.
+                           It will be published right after "config" message in order to update HA state.
+     */
     HASwitch(
         const char* name,
         bool initialState,
@@ -16,25 +23,61 @@ public:
     );
     virtual ~HASwitch();
 
+    /**
+     * Publishes configuration of the sensor to the MQTT.
+     */
     virtual void onMqttConnected() override;
+
+    /**
+     * Processes message received from the MQTT broker.
+     * The method updates state of the switch (if message matches switch'es topic).
+     */
     virtual void onMqttMessage(
         const char* topic,
         const char* payload,
         const uint16_t& length
     ) override;
 
+    /**
+     * Returns name of the switch assigned via constructor.
+     */
     inline const char* getName() const
         { return _name; }
 
-    void setState(bool state);
-    void turnOn();
-    void turnOff();
+    /**
+     * Changes state of the switch and publishes MQTT message.
+     * Please note that if a new value is the same as previous one,
+     * the MQTT message won't be published.
+     *
+     * @param state New state of the switch.
+     * @returns Returns true if MQTT message has been published successfully.
+     */
+    bool setState(bool state);
+
+    /**
+     * Alias for setState(true).
+     */
+    inline bool turnOn()
+        { return setState(true); }
+
+    /**
+     * Alias for setState(false).
+     */
+    inline bool turnOff()
+        { return setState(false); }
+
+    /**
+     * Registers callback that will be called each time the value of the switch changes.
+     * Please note that it's not possible to register multiple callbacks for the same switch.
+     *
+     * @param callback
+     */
     void onStateChanged(HASWITCH_CALLBACK);
 
 private:
     void triggerCallback(bool state);
     void publishConfig();
-    void publishCurrentState();
+    bool publishState(bool state);
     void subscribeCommandTopic();
     uint16_t calculateSerializedLength(const char* serializedDevice) const;
     bool writeSerializedTrigger(const char* serializedDevice) const;