Jungfraujoch/image_puller/ImagePuller.h

// SPDX-FileCopyrightText: 2025 Filip Leonarski, Paul Scherrer Institute <filip.leonarski@psi.ch>
// SPDX-License-Identifier: GPL-3.0-only

#pragma once

#include <string>
#include <memory>

#include "../common/ZMQWrappers.h"
#include "../frame_serialize/CBORStream2Deserializer.h"
#include "../common/ThreadSafeFIFO.h"
#include "../common/JfjochTCP.h"

struct PullerAckMessage {
    TCPFrameType ack_for = TCPFrameType::DATA;
    bool ok = true;
    bool fatal = false;
    uint64_t run_number = 0;
    uint32_t socket_number = 0;
    uint64_t image_number = 0;
    uint64_t processed_images = 0;
    TCPAckCode error_code = TCPAckCode::None;
    std::string error_text;
};

struct RawFrame {
    TcpFrameHeader header{};
    std::vector<uint8_t> payload;
    bool end = false;
};

struct ImagePullerOutput {
    std::shared_ptr<ZMQMessage> zmq_msg;
    std::shared_ptr<RawFrame> tcp_msg;
    std::shared_ptr<CBORStream2DeserializerOutput> cbor;
};

struct ImagePullerStatistics {
    size_t outside_fifo_max_util = 0;
};

class ImagePuller {
protected:
    ThreadSafeFIFO<ImagePullerOutput> outside_fifo; // assuming 1 file is <1000 files, this should be enough to buffer
public:
    constexpr static size_t DefaultQueueSize = 1000;
    constexpr static auto PollTimeout = std::chrono::milliseconds(100);

    explicit ImagePuller(size_t fifo_size = DefaultQueueSize);
    virtual ~ImagePuller() = default;

    [[nodiscard]] std::optional<ImagePullerOutput> PollImage(std::chrono::microseconds timeout = PollTimeout);
    [[nodiscard]] size_t GetMaxFifoUtilization() const;
    [[nodiscard]] size_t GetCurrentFifoUtilization() const;

    virtual bool SupportsAck() const { return false; }
    virtual bool SendAck(const PullerAckMessage &) { return false; }

    virtual void Disconnect() = 0;
};