Add the ASS sub document and the ASS tree

Also add views for the ASS tree in read only mode for now

src/Lib/Ass/Syl.cc

@@ -6,10 +6,25 @@ using namespace Vivy::Ass;
 Syl::Syl(Line *const line, const QString &lineString, ConstructMode mode) noexcept
     : content(lineString)
     , styleProperties(line->getStyleProperties())
-    , dur(line->getDuration())
+    , duration(line->getDuration())
     , parentLine(line)
 {
     // Will override the `content`, but will be heavy anyway
     if (mode == ConstructMode::ReadAssTags) {
+        const int textBegin = lineString.lastIndexOf('}') + 1;
+        content             = (textBegin >= lineString.size()) ? "" : lineString.mid(textBegin);
+        duration            = getDurationFromString(lineString);
     }
 }
+
+quint64
+Syl::getDurationFromString(const QString &line) noexcept
+{
+    QRegExp re("\\\\(?:k|K|ko|kf)(\\d+)");
+    int pos          = 0;
+    quint64 duration = 0;
+    while ((pos = re.indexIn(line, pos)) != -1) {
+        duration += re.cap(1).toUInt();
+    }
+    return duration;
+}