Video playback with mpv

Add video playback with mpv

• Add the mpv widget
• Enable the widget only for video able documents
• Control the widget with a small set of buttons
• Seek mpv with slider that indicates the current position in the video
• Use std::chrono in the MpvControls to be sure to have the correct time unit...

Not mpv related changes

• Don't del and add docks if they are already present, just swap the contained widget => don't reset the position of the dock at sub-document updates

What it does not for now :

• Get rid of controls on MPV view when the dock goes fullscreen

src/UI/DocumentViews/MpvContainer.cc

@@ -104,7 +104,7 @@ MpvContainer::handleMpvEvent(mpv_event *event) noexcept
 
     case MPV_EVENT_LOG_MESSAGE:
         msg = reinterpret_cast<mpv_event_log_message *>(event->data);
-        qDebug() << "MPV message: [" << msg->prefix << "]" << msg->level << ":" << msg->text;
+        qDebug("MPV - MSG [%s] %s: %s", msg->prefix, msg->level, msg->text);
         break;
 
     case MPV_EVENT_PROPERTY_CHANGE:
@@ -142,11 +142,26 @@ MpvContainer::handleMpvEvent(mpv_event *event) noexcept
         qDebug() << "MPV: Reached end of file!";
         break;
 
+    case MPV_EVENT_COMMAND_REPLY:
+        qDebug() << "Got return of" << event->reply_userdata;
+        switch (static_cast<AsyncCmdType>(event->reply_userdata)) {
+        case AsyncCmdType::None:
+            break;
+
+        case AsyncCmdType::LoadFile:
+            qDebug() << "MPV - CMD: File loaded by mpv";
+            break;
+
+        case AsyncCmdType::TogglePlayback:
+            qDebug() << "MPV - CMD: Playback was toggled";
+            break;
+        }
+        break;
+
     // Explicitly ignored
     case MPV_EVENT_NONE:
     case MPV_EVENT_GET_PROPERTY_REPLY:
     case MPV_EVENT_SET_PROPERTY_REPLY:
-    case MPV_EVENT_COMMAND_REPLY:
     case MPV_EVENT_FILE_LOADED:
     case MPV_EVENT_TRACKS_CHANGED:
     case MPV_EVENT_TRACK_SWITCHED:
@@ -184,7 +199,7 @@ MpvContainer::loadFile(const QString &filename) noexcept
 
     const QByteArray c_filename = filename.toUtf8();
     const char *args[]          = { "loadfile", c_filename.data(), nullptr };
-    printMpvError(mpv_command_async(mpv, 0, args));
+    printMpvError(mpv_command_async(mpv, AsyncCmdType::LoadFile, args));
 }
 
 void
@@ -214,5 +229,5 @@ void
 MpvContainer::mpvTogglePlayback() noexcept
 {
     const char *cmd[] = { "cycle", "pause", "up", nullptr };
-    printMpvError(mpv_command_async(mpv, 0, cmd));
+    printMpvError(mpv_command_async(mpv, AsyncCmdType::TogglePlayback, cmd));
 }