From d1d9008ffeb6eb252cb10dafa83257adcb80845c Mon Sep 17 00:00:00 2001
From: Stenzek <stenzek@gmail.com>
Date: Sun, 30 Nov 2025 19:05:00 +1000
Subject: [PATCH] Qt: Add QtAsyncTaskWithProgress

---
 src/duckstation-qt/qtprogresscallback.cpp | 100 ++++++++++++++++++++++
 src/duckstation-qt/qtprogresscallback.h   |  46 ++++++++++
 2 files changed, 146 insertions(+)

diff --git a/src/duckstation-qt/qtprogresscallback.cpp b/src/duckstation-qt/qtprogresscallback.cpp
index 8125c33c7..01aae01ec 100644
--- a/src/duckstation-qt/qtprogresscallback.cpp
+++ b/src/duckstation-qt/qtprogresscallback.cpp
@@ -77,6 +77,106 @@ void QtProgressCallback::connectWidgets(QLabel* const status_label, QProgressBar
   }
 }
 
+QtAsyncTaskWithProgress::QtAsyncTaskWithProgress() : QObject()
+{
+}
+
+QtAsyncTaskWithProgress::~QtAsyncTaskWithProgress() = default;
+
+bool QtAsyncTaskWithProgress::IsCancelled() const
+{
+  return m_ts_cancelled.load(std::memory_order_acquire);
+}
+
+void QtAsyncTaskWithProgress::SetTitle(const std::string_view title)
+{
+  emit titleUpdated(QtUtils::StringViewToQString(title));
+}
+
+void QtAsyncTaskWithProgress::SetStatusText(const std::string_view text)
+{
+  ProgressCallback::SetStatusText(text);
+  emit statusTextUpdated(QtUtils::StringViewToQString(text));
+}
+
+void QtAsyncTaskWithProgress::SetProgressRange(u32 range)
+{
+  const u32 prev_range = m_progress_range;
+  ProgressCallback::SetProgressRange(range);
+  if (m_progress_range == prev_range)
+    return;
+
+  emit progressRangeUpdated(0, static_cast<int>(m_progress_range));
+}
+
+void QtAsyncTaskWithProgress::SetProgressValue(u32 value)
+{
+  const u32 prev_value = m_progress_value;
+  ProgressCallback::SetProgressValue(value);
+  if (m_progress_value == prev_value)
+    return;
+
+  emit progressValueUpdated(static_cast<int>(m_progress_value));
+}
+
+void QtAsyncTaskWithProgress::connectWidgets(QLabel* const status_label, QProgressBar* const progress_bar,
+                                             QAbstractButton* const cancel_button)
+{
+  if (status_label)
+    connect(this, &QtAsyncTaskWithProgress::statusTextUpdated, status_label, &QLabel::setText);
+  if (progress_bar)
+  {
+    connect(this, &QtAsyncTaskWithProgress::progressRangeUpdated, progress_bar, &QProgressBar::setRange);
+    connect(this, &QtAsyncTaskWithProgress::progressValueUpdated, progress_bar, &QProgressBar::setValue);
+  }
+  if (cancel_button)
+  {
+    // force direct connection so it executes on the calling thread
+    connect(
+      cancel_button, &QAbstractButton::clicked, this,
+      [this]() { m_ts_cancelled.store(true, std::memory_order_release); }, Qt::DirectConnection);
+  }
+}
+
+QtAsyncTaskWithProgress* QtAsyncTaskWithProgress::create(QWidget* const callback_parent, WorkCallback callback)
+{
+  QtAsyncTaskWithProgress* self = new QtAsyncTaskWithProgress();
+  self->m_callback = std::move(callback);
+
+  connect(self, &QtAsyncTaskWithProgress::completed, callback_parent, [self]() {
+    const CompletionCallback& cb = std::get<CompletionCallback>(self->m_callback);
+    if (cb)
+      cb();
+  });
+
+  return self;
+}
+
+void QtAsyncTaskWithProgress::start()
+{
+  // Disconnect from the calling thread, so it can be pulled by the async task.
+  moveToThread(nullptr);
+
+  System::QueueAsyncTask([this]() mutable {
+    QThread* const worker_thread = QThread::currentThread();
+    moveToThread(worker_thread);
+
+    m_callback = std::get<WorkCallback>(m_callback)(this);
+    moveToThread(nullptr);
+
+    Host::RunOnUIThread([self = this]() {
+      self->moveToThread(QThread::currentThread());
+      emit self->completed();
+      delete self;
+    });
+  });
+}
+
+void QtAsyncTaskWithProgress::cancel()
+{
+  m_ts_cancelled.store(true, std::memory_order_release);
+}
+
 QtAsyncTaskWithProgressDialog::QtAsyncTaskWithProgressDialog(const QString& initial_title,
                                                              const QString& initial_status_text, bool cancellable,
                                                              int range, int value, float show_delay,
diff --git a/src/duckstation-qt/qtprogresscallback.h b/src/duckstation-qt/qtprogresscallback.h
index 5d13ec8be..a8df39925 100644
--- a/src/duckstation-qt/qtprogresscallback.h
+++ b/src/duckstation-qt/qtprogresscallback.h
@@ -42,6 +42,52 @@ private:
   std::atomic_bool m_ts_cancelled{false};
 };
 
+class QtAsyncTaskWithProgress final : public QObject, private ProgressCallback
+{
+  Q_OBJECT
+
+public:
+  using CompletionCallback = std::function<void()>;
+  using WorkCallback = std::function<CompletionCallback(ProgressCallback*)>;
+
+  ~QtAsyncTaskWithProgress() override;
+
+  /// Creates a task, the task is still in the pending state until start() is called.
+  static QtAsyncTaskWithProgress* create(QWidget* const callback_parent, WorkCallback callback);
+
+  /// Starts the task asynchronously. The pointer is only guaranteed to be valid until the
+  /// completion callback has executed.
+  void start();
+
+  /// Cancel the task asynchronously. If the callback_parent that was set in start() is no
+  /// longer valid, the completion handler will not execute.
+  void cancel();
+
+  /// Connects progress updates to a typical set of widgets.
+  void connectWidgets(QLabel* const status_label, QProgressBar* const progress_bar,
+                      QAbstractButton* const cancel_button);
+
+Q_SIGNALS:
+  void titleUpdated(const QString& title);
+  void statusTextUpdated(const QString& status);
+  void progressRangeUpdated(int min, int max);
+  void progressValueUpdated(int value);
+  void completed();
+
+protected:
+  bool IsCancelled() const override;
+  void SetTitle(const std::string_view title) override;
+  void SetStatusText(const std::string_view text) override;
+  void SetProgressRange(u32 range) override;
+  void SetProgressValue(u32 value) override;
+
+private:
+  QtAsyncTaskWithProgress();
+
+  std::variant<WorkCallback, CompletionCallback> m_callback;
+  std::atomic_bool m_ts_cancelled{false};
+};
+
 class QtAsyncTaskWithProgressDialog final : public QObject, private ProgressCallback
 {
   Q_OBJECT