code integration

sdi_toolBox_2.x.x/toolBox/sdi_toolBox/desktop/eventBus/message.h

@@ -0,0 +1,195 @@
+/*
+ Copyright (c) 2026 - SD-Innovation S.A.S. - FRANCE
+*/
+
+/*
+ver: 2.x.x - build: 2026-04-28
+*/
+
+/*
+The zlib License
+
+Copyright (c) 2026 SD-Innovation S.A.S.
+
+This software is provided ‘as-is’, without any express or implied
+warranty. In no event will the authors be held liable for any damages
+arising from the use of this software.
+
+Permission is granted to anyone to use this software for any purpose,
+including commercial applications, and to alter it and redistribute it
+freely, subject to the following restrictions:
+
+1. The origin of this software must not be misrepresented; you must not
+claim that you wrote the original software. If you use this software
+in a product, an acknowledgment in the product documentation would be
+appreciated but is not required.
+
+2. Altered source versions must be plainly marked as such, and must not be
+misrepresented as being the original software.
+
+3. This notice may not be removed or altered from any source
+distribution.
+*/
+
+#pragma once
+
+#include "defs.h"
+
+namespace sdi_toolBox::desktop::eventBus
+{
+//--------------------------------------------------------------
+/**
+ * @class Message
+ * @brief Base class for all messages dispatched through the event bus.
+ *
+ * Every message circulating in the event bus system must derive from this class.
+ * It carries a unique message type identifier (@ref MessageTypeID) used by the
+ * @ref Bus to route the message to the appropriate subscribers, and a timestamp
+ * that is updated when the message is posted to the bus.
+ *
+ * @note The Message class is non-copyable and non-movable.
+ * @note The default constructor is deleted: a @ref MessageTypeID must always
+ *       be provided at construction time.
+ * @note The timestamp is set by the @ref Bus internally when @ref Bus::post()
+ *       is called; it is not set at construction time.
+ *
+ * @par Example - defining a custom message:
+ * @code
+ * static constexpr sdi_toolBox::desktop::eventBus::MessageTypeID MY_EVENT = 1;
+ *
+ * struct MyMessage : public sdi_toolBox::desktop::eventBus::Message
+ * {
+ *   explicit MyMessage(int value)
+ *     : Message(MY_EVENT)
+ *     , payload(value)
+ *   {}
+ *   int payload{};
+ * };
+ * @endcode
+ *
+ * @see Bus
+ * @see MessageTypeID
+ * @see TimePoint
+ */
+class Message
+{
+  friend class Bus;     ///< Allow the Bus class to access private members
+
+  public:
+  ///@name Construction & Destruction
+  ///@{
+
+  /**
+   * @brief Default constructor - deleted.
+   *
+   * A @ref MessageTypeID must always be provided at construction time.
+   */
+  Message() = delete;
+
+  /**
+   * @brief Default destructor.
+   */
+  virtual ~Message() = default;
+
+  /**
+   * @brief Copy constructor - deleted.
+   *
+   * Message is non-copyable.
+   */
+  Message(const Message &obj) = delete;
+
+  /**
+   * @brief Move constructor - deleted.
+   *
+   * Message is non-movable.
+   */
+  Message(Message &&obj) noexcept = delete;
+
+  /**
+   * @brief Copy assignment operator - deleted.
+   *
+   * Message is non-copyable.
+   */
+  Message &operator=(const Message &obj) = delete;
+
+  /**
+   * @brief Move assignment operator - deleted.
+   *
+   * Message is non-movable.
+   */
+  Message &operator=(Message &&obj) noexcept = delete;
+
+  /**
+   * @brief Construct a message with the given type identifier.
+   *
+   * @param messageTypeID Unique identifier representing the type of this message.
+   *                      Used by the @ref Bus to route the message to the correct
+   *                      subscribers.
+   */
+  explicit Message(MessageTypeID messageTypeID);
+
+  ///@}
+  ///@name Accessors
+  ///@{
+
+  /**
+   * @brief Get the unique type identifier of this message.
+   *
+   * @return The @ref MessageTypeID assigned at construction time.
+   */
+  [[nodiscard]] MessageTypeID getMessageTypeID() const;
+
+  /**
+   * @brief Get the timestamp of when this message was posted to the bus.
+   *
+   * The timestamp is recorded by the @ref Bus when @ref Bus::post() is called.
+   * It is left at its default-constructed (zero) value if the message has not
+   * yet been posted.
+   *
+   * @return A @ref TimePoint representing the moment the message was dispatched.
+   * @see Bus::post()
+   */
+  [[nodiscard]] TimePoint getTimestamp() const;
+
+  ///@}
+
+  private:
+  /**
+   * @brief Update the message timestamp to the current time.
+   *
+   * Called internally by @ref Bus::post() just before the message is dispatched
+   * to subscribers. Not accessible from outside the bus.
+   */
+  void updateTimestamp();
+
+  MessageTypeID m_messageTypeID;              ///< Unique identifier for the message type
+  TimePoint     m_messagePostTimestamp{};     ///< Timestamp of when the message was posted to the bus
+};
+//--------------------------------------------------------------
+
+//--------------------------------------------------------------
+/* Constructor */
+inline Message::Message(const MessageTypeID messageTypeID)
+{
+  m_messageTypeID = messageTypeID;
+}
+//--------------------------------------------------------------
+/* Get the unique identifier for the message type */
+inline MessageTypeID Message::getMessageTypeID() const
+{
+  return m_messageTypeID;
+}
+//--------------------------------------------------------------
+/* Get the timestamp of when the message was posted to the bus */
+inline TimePoint Message::getTimestamp() const
+{
+  return m_messagePostTimestamp;
+}
+//--------------------------------------------------------------
+/* Update the timestamp of when the message was posted to the bus */
+inline void Message::updateTimestamp()
+{
+  m_messagePostTimestamp = std::chrono::steady_clock::now();
+}
+//--------------------------------------------------------------
+}     // namespace sdi_toolBox::desktop::eventBus