Piano: Show a progress window when exporting WAV

This exposes that the export is pretty slow, but it's much nicer than
having the GUI lock up for 20s :^)

Userland/Applications/Piano/AudioPlayerLoop.cpp

@@ -47,7 +47,7 @@ struct AudioLoopDeferredInvoker final : public IPC::DeferredInvoker {
     Vector<Function<void()>, INLINE_FUNCTIONS> deferred_functions;
 };
 
-AudioPlayerLoop::AudioPlayerLoop(TrackManager& track_manager, Atomic<bool>& need_to_write_wav, Threading::MutexProtected<Audio::WavWriter>& wav_writer)
+AudioPlayerLoop::AudioPlayerLoop(TrackManager& track_manager, Atomic<bool>& need_to_write_wav, Atomic<int>& wav_percent_written, Threading::MutexProtected<Audio::WavWriter>& wav_writer)
     : m_track_manager(track_manager)
     , m_buffer(FixedArray<DSP::Sample>::must_create_but_fixme_should_propagate_errors(sample_count))
     , m_pipeline_thread(Threading::Thread::construct([this]() {
@@ -55,6 +55,7 @@ AudioPlayerLoop::AudioPlayerLoop(TrackManager& track_manager, Atomic<bool>& need
     },
           "Audio pipeline"sv))
     , m_need_to_write_wav(need_to_write_wav)
+    , m_wav_percent_written(wav_percent_written)
     , m_wav_writer(wav_writer)
 {
     m_audio_client = Audio::ConnectionToServer::try_create().release_value_but_fixme_should_propagate_errors();
@@ -139,10 +140,13 @@ void AudioPlayerLoop::write_wav_if_needed()
             m_track_manager.reset();
             m_track_manager.set_should_loop(false);
             do {
+                // FIXME: This progress detection is crude, but it works for now.
+                m_wav_percent_written.store(static_cast<int>(static_cast<float>(m_track_manager.transport()->time()) / roll_length * 100.0f));
                 m_track_manager.fill_buffer(m_buffer);
                 wav_writer.write_samples(m_buffer.span());
             } while (m_track_manager.transport()->time());
             // FIXME: Make sure that the new TrackManager APIs aren't as bad.
+            m_wav_percent_written.store(100);
             m_track_manager.reset();
             m_track_manager.set_should_loop(true);
             wav_writer.finalize();

Userland/Applications/Piano/AudioPlayerLoop.h

@@ -30,7 +30,7 @@ public:
     bool is_playing() const { return m_should_play_audio; }
 
 private:
-    AudioPlayerLoop(TrackManager& track_manager, Atomic<bool>& need_to_write_wav, Threading::MutexProtected<Audio::WavWriter>& wav_writer);
+    AudioPlayerLoop(TrackManager& track_manager, Atomic<bool>& need_to_write_wav, Atomic<int>& wav_percent_written, Threading::MutexProtected<Audio::WavWriter>& wav_writer);
 
     intptr_t pipeline_thread_main();
     ErrorOr<void> send_audio_to_server();
@@ -47,5 +47,6 @@ private:
     Atomic<bool> m_exit_requested { false };
 
     Atomic<bool>& m_need_to_write_wav;
+    Atomic<int>& m_wav_percent_written;
     Threading::MutexProtected<Audio::WavWriter>& m_wav_writer;
 };

Userland/Applications/Piano/CMakeLists.txt

@@ -5,8 +5,11 @@ serenity_component(
     DEPENDS AudioServer
 )
 
+compile_gml(ExportProgressWidget.gml ExportProgressWidget.h export_progress_widget)
+
 set(SOURCES
     AudioPlayerLoop.cpp
+    ExportProgressWindow.cpp
     KeysWidget.cpp
     KnobsWidget.cpp
     main.cpp
@@ -20,5 +23,9 @@ set(SOURCES
     ProcessorParameterWidget/Slider.cpp
 )
 
+set(GENERATED_SOURCES
+    ExportProgressWidget.h
+)
+
 serenity_app(Piano ICON app-piano)
 target_link_libraries(Piano PRIVATE LibAudio LibCore LibDSP LibGfx LibGUI LibIPC LibMain LibThreading)

Userland/Applications/Piano/ExportProgressWidget.gml

@@ -0,0 +1,22 @@
+@GUI::Widget {
+    fill_with_background_color: true
+    layout: @GUI::VerticalBoxLayout {
+        margins: [4]
+    }
+
+    @GUI::Label {
+        name: "export_message"
+        text_alignment: "Center"
+        // FIXME: Change to dynamic width once that works.
+        min_width: 300
+        preferred_height: "fit"
+    }
+
+    @GUI::HorizontalProgressbar {
+        name: "progress_bar"
+        min: 0
+        max: 100
+        preferred_width: "grow"
+        min_height: 40
+    }
+}

Userland/Applications/Piano/ExportProgressWindow.cpp

@@ -0,0 +1,55 @@
+/*
+ * Copyright (c) 2022, kleines Filmröllchen <filmroellchen@serenityos.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include "ExportProgressWindow.h"
+#include "LibGUI/Icon.h"
+#include <AK/DeprecatedString.h>
+#include <Applications/Piano/ExportProgressWidget.h>
+#include <LibGUI/Label.h>
+#include <LibGUI/Widget.h>
+#include <LibGUI/Window.h>
+
+ExportProgressWindow::ExportProgressWindow(GUI::Window& parent_window, Atomic<int>& wav_percent_written)
+    : GUI::Dialog(&parent_window)
+    , m_wav_percent_written(wav_percent_written)
+{
+}
+
+ErrorOr<void> ExportProgressWindow::initialize_fallibles()
+{
+    auto main_widget = TRY(set_main_widget<GUI::Widget>());
+    TRY(main_widget->load_from_gml(export_progress_widget));
+
+    set_resizable(false);
+    set_closeable(false);
+    set_title("Rendering audio");
+    set_icon(GUI::Icon::default_icon("app-piano"sv).bitmap_for_size(16));
+
+    m_progress_bar = *main_widget->find_descendant_of_type_named<GUI::HorizontalProgressbar>("progress_bar");
+    m_label = *main_widget->find_descendant_of_type_named<GUI::Label>("export_message");
+
+    start_timer(250);
+
+    return {};
+}
+
+void ExportProgressWindow::set_filename(StringView filename)
+{
+    m_label->set_text(DeprecatedString::formatted("Rendering audio to {}…", filename));
+    update();
+}
+
+void ExportProgressWindow::timer_event(Core::TimerEvent&)
+{
+    m_progress_bar->set_value(m_wav_percent_written.load());
+    if (window_id() != 0)
+        set_progress(m_wav_percent_written.load());
+
+    if (m_wav_percent_written.load() == 100) {
+        m_wav_percent_written.store(0);
+        close();
+    }
+}

Userland/Applications/Piano/ExportProgressWindow.h

@@ -0,0 +1,33 @@
+/*
+ * Copyright (c) 2022, kleines Filmröllchen <filmroellchen@serenityos.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#pragma once
+
+#include <LibCore/Event.h>
+#include <LibGUI/Dialog.h>
+#include <LibGUI/Label.h>
+#include <LibGUI/Progressbar.h>
+
+class ExportProgressWindow : public GUI::Dialog {
+    C_OBJECT(ExportProgressWindow);
+
+public:
+    virtual ~ExportProgressWindow() override = default;
+
+    ErrorOr<void> initialize_fallibles();
+
+    virtual void timer_event(Core::TimerEvent&) override;
+
+    void set_filename(StringView filename);
+
+private:
+    ExportProgressWindow(Window& parent_window, Atomic<int>& wav_percent_written);
+
+    Atomic<int>& m_wav_percent_written;
+
+    RefPtr<GUI::HorizontalProgressbar> m_progress_bar;
+    RefPtr<GUI::Label> m_label;
+};

Userland/Applications/Piano/main.cpp

@@ -8,6 +8,7 @@
  */
 
 #include "AudioPlayerLoop.h"
+#include "ExportProgressWindow.h"
 #include "MainWidget.h"
 #include "TrackManager.h"
 #include <AK/Atomic.h>
@@ -37,8 +38,9 @@ ErrorOr<int> serenity_main(Main::Arguments arguments)
     Threading::MutexProtected<Audio::WavWriter> wav_writer;
     Optional<DeprecatedString> save_path;
     Atomic<bool> need_to_write_wav = false;
+    Atomic<int> wav_percent_written = 0;
 
-    auto audio_loop = AudioPlayerLoop::construct(track_manager, need_to_write_wav, wav_writer);
+    auto audio_loop = AudioPlayerLoop::construct(track_manager, need_to_write_wav, wav_percent_written, wav_writer);
 
     auto app_icon = GUI::Icon::default_icon("app-piano"sv);
     auto window = TRY(GUI::Window::try_create());
@@ -47,6 +49,9 @@ ErrorOr<int> serenity_main(Main::Arguments arguments)
     window->resize(840, 600);
     window->set_icon(app_icon.bitmap_for_size(16));
 
+    auto wav_progress_window = ExportProgressWindow::construct(*window, wav_percent_written);
+    TRY(wav_progress_window->initialize_fallibles());
+
     auto main_widget_updater = TRY(Core::Timer::create_repeating(static_cast<int>((1 / 30.0) * 1000), [&] {
         if (window->is_active())
             Core::EventLoop::current().post_event(main_widget, make<Core::CustomEvent>(0));
@@ -71,6 +76,8 @@ ErrorOr<int> serenity_main(Main::Arguments arguments)
             return;
         }
         need_to_write_wav = true;
+        wav_progress_window->set_filename(save_path.value());
+        wav_progress_window->show();
     })));
     TRY(file_menu->try_add_separator());
     TRY(file_menu->try_add_action(GUI::CommonActions::make_quit_action([](auto&) {