Implement the VivyDocument specification

Load and write to VivyDocuments.

While at it, refactor of {Audio,Video}Context and their streams and fix all warnings in headers with clang. Only place external headers in the precompiled header, not Vivy's ones.

Includes a small API update for the VideoSubDocument (ass the VideoContext with some getters).

Depends on !19 (merged)

src/Lib/Document/VivyDocument.cc

@@ -6,6 +6,8 @@
 #include <QStringList>
 #include <QJsonArray>
 #include <QJsonObject>
+#include <QJsonDocument>
+#include <QTextStream>
 
 using namespace Vivy;
 
@@ -13,13 +15,48 @@ VivyDocument::VivyDocument(const QString &documentPath, Options opt)
     : AbstractDocument(AbstractDocument::Type::Vivy, documentPath)
     , documentOptions(opt)
 {
-    QFileInfo file(name);
-    documentName     = file.baseName();
-    documentLocation = file.absoluteDir();
+    QFileInfo fileInfo(name);
+    QFile file(name);
+    documentName     = fileInfo.baseName();
+    documentLocation = fileInfo.absoluteDir();
+
+    if (fileInfo.completeSuffix() != fileSuffix)
+        throw std::runtime_error("Invalid file suffix");
+
+    if (!file.exists() || !fileInfo.isFile() || !file.open(QIODevice::ReadOnly | QIODevice::Text))
+        throw std::runtime_error("Document doesn't exists");
+
+    QTextStream fileContent(&file);
+    QJsonParseError jsonError;
+    QJsonDocument json = QJsonDocument::fromJson(fileContent.readAll().toUtf8(), &jsonError);
+
+    if (json.isNull())
+        throw std::runtime_error("Json error " + jsonError.errorString().toStdString());
+
+    // Init from the JSON
+    documentType = json[KeyCapabilities].toString().toULongLong() & possibleCapabilities;
+    if (json[KeyName].toString() != documentName)
+        throw std::runtime_error("The document was edited outside of Vivy");
+
+    if (QJsonValue audio = json[KeySubDocuments][KeySubAudio]; !audio.isNull())
+        loadSubDocument(audio.toString(), Capabilities::AudioAble);
+    if (QJsonValue video = json[KeySubDocuments][KeySubVideo]; !video.isNull())
+        loadSubDocument(video.toString(), Capabilities::VideoAble);
+
+    if (QJsonValue internalAssSource = json[KeySubDocuments][KeyInternalAssSource];
+        !internalAssSource.isNull() && internalAssSource.toBool()) {
+        // ASS is inside Vivy document
+        throw std::runtime_error("The internal ASS feature is not supported for now");
+    } else if (QJsonValue ass = json[KeySubDocuments][KeySubAss]; !ass.isNull()) {
+        // ASS in its own ASS file
+        loadSubDocument(ass.toString(), Capabilities::AssAble);
+    }
+}
 
-    loadSubDocument(name);
-    qDebug() << "CONSTRUCTOR: VivyDocument(" << name << "," << opt << ","
-             << getDocumentCapabilitiesString() << ")";
+bool
+VivyDocument::save() const noexcept
+{
+    return false;
 }
 
 bool
@@ -108,7 +145,7 @@ VivyDocument::rename(const QString &newName) noexcept
 {
     /* Compute new paths */
     const QString newNameWithExtension =
-        newName.right(filePrefix.size()) == filePrefix ? newName : newName + "." + filePrefix;
+        newName.right(fileSuffix.size()) == fileSuffix ? newName : newName + "." + fileSuffix;
     const QFileInfo newPath(documentLocation, newNameWithExtension);
 
     return renameWith(newPath, [=, this]() noexcept -> void {