// SPDX-FileCopyrightText: 2026 Filip Leonarski, Paul Scherrer Institute <filip.leonarski@psi.ch>
// SPDX-License-Identifier: GPL-3.0-only

#pragma once

#include <QObject>
#include <QString>

#include <atomic>
#include <chrono>
#include <memory>
#include <mutex>
#include <thread>

#include "../process/JFJochProcess.h"
#include "../common/DiffractionExperiment.h"
#include "../common/PixelMask.h"
#include "../reader/JFJochReaderDataset.h"

Q_DECLARE_METATYPE(ProcessResult)

// Runs one JFJochProcess job off the GUI thread and reports back via queued Qt signals. The job
// opens its own private JFJochHDF5Reader on the file (HDF5 access is globally serialized, so this
// is safe alongside the interactive reader), so the viewer becomes a processing frontend without
// blocking the UI. Cancel() is forwarded to JFJochProcess::Cancel() (atomic) and works from any
// thread / at any point of the run.
class JFJochProcessController : public QObject, private JFJochProcessObserver {
    Q_OBJECT
public:
    explicit JFJochProcessController(QObject *parent = nullptr);
    ~JFJochProcessController() override;

    bool running() const { return running_; }

public slots:
    // Start a job over `file_path` with the given (fully configured) experiment + mask + config.
    // Ignored if a job is already running.
    void start(const QString &file_path, DiffractionExperiment experiment,
               PixelMask pixel_mask, ProcessConfig config);
    void cancel();

signals:
    void started();
    void phaseChanged(QString phase);
    void progress(quint64 done, quint64 total);
    void finished(ProcessResult result);
    void failed(QString error);
    // Per-image results accumulated so far, for live dataset-info plots while a job runs (throttled).
    void liveDataset(std::shared_ptr<const JFJochReaderDataset> dataset);

private:
    // JFJochProcessObserver - called from worker threads, forwarded as queued signals.
    void OnPhase(const std::string &phase) override;
    void OnProgress(uint64_t done, uint64_t total) override;
    void OnImageProcessed(const DataMessage &msg) override;

    void run_(QString file_path, DiffractionExperiment experiment, PixelMask pixel_mask, ProcessConfig config);
    void joinWorker_();

    std::thread worker_;
    std::atomic<JFJochProcess *> active_{nullptr};
    std::atomic<bool> running_{false};
    std::atomic<bool> cancel_pending_{false};

    // Live per-image results, accumulated by OnImageProcessed (worker threads) and emitted as
    // immutable copies. live_mutex_ guards both the dataset and the throttle timestamp.
    std::mutex live_mutex_;
    std::shared_ptr<JFJochReaderDataset> live_dataset_;
    std::chrono::steady_clock::time_point last_live_emit_;
};