/**
 * @file TCPStreamer.h
 * @brief Header file for class TCPStreamer
 * @date 05/11/2026
 * @author Martino Ferrari
 *
 * @copyright Copyright 2015 F4E | European Joint Undertaking for ITER and
 * the Development of Fusion Energy ('Fusion for Energy').
 * Licensed under the EUPL, Version 1.1 or - as soon they will be approved
 * by the European Commission - subsequent versions of the EUPL (the "Licence")
 * You may not use this work except in compliance with the Licence.
 * You may obtain a copy of the Licence at: http://ec.europa.eu/idabc/eupl
 *
 * @warning Unless required by applicable law or agreed to in writing,
 * software distributed under the Licence is distributed on an "AS IS"
 * basis, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
 * or implied. See the Licence permissions and limitations under the Licence.
 *
 * @details This header file contains the declaration of the class TCPStreamer
 * with all of its public, protected and private members.
 */

#ifndef TCPSTREAMER_H_
#define TCPSTREAMER_H_

#include "TCPSServer.h"
#include "TCPSServiceStream.h"
#include "UDPStreamer.h"

namespace MARTe {

/**
 * @brief A DataSource that streams MARTe2 signals to TCP clients.
 *
 * @details Identical to UDPStreamer (same signals, quantisation, time modes and
 * PublishingMode handling, same UDPS wire format) except that the network side
 * is a TCPSServer: every client gets the CONFIG on connect and then every DATA
 * frame, in order, over its own TCP connection. A client that cannot keep up
 * only loses its own frames (counted by GetClientDrops()) and is disconnected
 * after ClientStallTimeout seconds without progress; the RT thread and the
 * other clients are unaffected.
 *
 * @par Configuration
 * All UDPStreamer keys apply except the UDP-only ones (MulticastGroup,
 * Interface, DataPort, ClientTimeout), which are rejected.
 * | Parameter          | Type   | Default | Description |
 * |--------------------|--------|---------|-------------|
 * | Port               | uint16 | 44500   | TCP listen port. |
 * | MaxPayloadSize     | uint32 | 60000   | Frame budget used to size Accumulate batches. |
 * | MaxClients         | uint32 | 16      | Simultaneous clients (1..1024). |
 * | ClientQueueDepth   | uint32 | 8       | DATA frames queued per client (1..4096). |
 * | ClientStallTimeout | uint32 | 5       | Seconds without progress before a client is dropped; 0 disables. |
 * | SendBufferSize     | uint32 | 0       | SO_SNDBUF for client sockets; 0 keeps the OS default. |
 *
 * @par Shared service mode
 * With `Service = <name of a TCPStreamService>` the DataSource does not open a
 * socket of its own: it publishes a stream called `StreamName` (default: the
 * DataSource name) through the shared in-process service, which serves many
 * streams from one port with a pool of worker threads. Clients select the
 * stream with the `StreamName` key of TCPStreamerClient / StreamHub. In this
 * mode Port, MaxClients, ClientQueueDepth, ClientStallTimeout and
 * SendBufferSize belong to the service and are rejected here.
 * | Parameter  | Type   | Default         | Description |
 * |------------|--------|-----------------|-------------|
 * | Service    | string | *(absent)*      | Object name of the TCPStreamService. |
 * | StreamName | string | DataSource name | Stream name, unique per service (1..255 chars). |
 *
 * @par Example
 * <pre>
 * +Streamer = {
 *     Class = TCPStreamer
 *     Port  = 44500
 *     Signals = {
 *         Time = { Type = uint64 }
 *         Value = { Type = float32 }
 *     }
 * }
 * </pre>
 */
class TCPStreamer : public UDPStreamer {
public:
    CLASS_REGISTER_DECLARATION()

    TCPStreamer();
    virtual ~TCPStreamer();

    /** Rejects the UDP-only keys, then behaves as UDPStreamer::Initialise(). */
    virtual bool Initialise(StructuredDataI &data);

    /** @return true when publishing through a TCPStreamService. */
    bool UsesService() const;
    /** @return the port actually bound (meaningful once started; resolves Port = 0). */
    uint16 GetBoundPort() const;
    /** @return clients currently connected. */
    uint32 GetClientCount() const;
    /** @return DATA frames dropped across all clients because their queue was full. */
    uint64 GetClientDrops() const;
    /** @return clients disconnected for exceeding ClientStallTimeout. */
    uint32 GetStallEvictions() const;

protected:
    virtual uint32 DefaultMaxPayloadSize() const;
    virtual bool InitialiseTransport(StructuredDataI &data);

private:
    TCPSServer *tcpServer;            /**< Alias of the private transport (NULL in service mode). */
    TCPSServiceStream *serviceStream; /**< Alias of the service handle (NULL in standalone mode). */
};

} /* namespace MARTe */

#endif /* TCPSTREAMER_H_ */