1 files changed, 87 insertions, 0 deletions
diff --git a/source/game/StarVersioningDatabase.hpp b/source/game/StarVersioningDatabase.hpp
new file mode 100644
index 0000000..859c313
--- /dev/null
+++ b/source/game/StarVersioningDatabase.hpp
@@ -0,0 +1,87 @@
+#ifndef STAR_VERSIONING_DATABASE_HPP
+#define STAR_VERSIONING_DATABASE_HPP
+
+#include "StarJson.hpp"
+#include "StarDataStream.hpp"
+#include "StarThread.hpp"
+#include "StarVersion.hpp"
+#include "StarLuaRoot.hpp"
+
+namespace Star {
+
+STAR_STRUCT(VersionedJson);
+STAR_CLASS(VersioningDatabase);
+
+STAR_EXCEPTION(VersionedJsonException, StarException);
+STAR_EXCEPTION(VersioningDatabaseException, StarException);
+
+struct VersionedJson {
+  static char const* const Magic;
+  static size_t const MagicStringSize;
+
+  // Writes and reads a binary file containing a versioned json with a magic
+  // header marking it as a starbound versioned json file.  Writes using a
+  // safe write/flush/swap.
+  static VersionedJson readFile(String const& filename);
+  static void writeFile(VersionedJson const& versionedJson, String const& filename);
+
+  // Writes and reads a json containing a versioned json
+  // This allows embedding versioned metadata within a file
+  static VersionedJson fromJson(Json const& source);
+  Json toJson() const;
+
+  bool empty() const;
+
+  // If the identifier does not match the given identifier, throws a
+  // VersionedJsonException.
+  void expectIdentifier(String const& expectedIdentifier) const;
+
+  String identifier;
+  VersionNumber version;
+  Json content;
+};
+
+DataStream& operator>>(DataStream& ds, VersionedJson& versionedJson);
+DataStream& operator<<(DataStream& ds, VersionedJson const& versionedJson);
+
+class VersioningDatabase {
+public:
+  VersioningDatabase();
+
+  // Converts the given content Json to a VersionedJson by marking it with the
+  // given identifier and the current version configured in the versioning
+  // config file.
+  VersionedJson makeCurrentVersionedJson(String const& identifier, Json const& content) const;
+
+  // Returns true if the version in this VersionedJson matches the configured
+  // current version and does not need updating.
+  bool versionedJsonCurrent(VersionedJson const& versionedJson) const;
+
+  // Brings the given versioned json up to the current configured latest
+  // version using update scripts.  If successful, returns the up to date
+  // VersionedJson, otherwise throws VersioningDatabaseException.
+  VersionedJson updateVersionedJson(VersionedJson const& versionedJson) const;
+
+  // Convenience method, checkts the versionedJson expected identifier and then
+  // brings the given versionedJson up to date and returns the content.
+  Json loadVersionedJson(VersionedJson const& versionedJson, String const& expectedIdentifier) const;
+
+private:
+  struct VersionUpdateScript {
+    String script;
+    VersionNumber fromVersion;
+    VersionNumber toVersion;
+  };
+
+  LuaCallbacks makeVersioningCallbacks() const;
+
+  mutable RecursiveMutex m_mutex;
+  mutable LuaRoot m_luaRoot;
+
+  StringMap<VersionNumber> m_currentVersions;
+  StringMap<List<VersionUpdateScript>> m_versionUpdateScripts;
+};
+
+}
+
+#endif