CmdAccess: **Big Bang** wire the first real command from UI down into the Session

...just the implementation within SessManagerImpl is not yet there P-)
So everything remains as defunct as before, but at least: "yes we can"

src/gui/interact/interaction-director.cpp

@@ -38,7 +38,10 @@
 #include "gui/setting/asset-controller.hpp"
 #include "gui/timeline/timeline-controller.hpp"
 #include "proc/mobject/session/root.hpp"
+#include "proc/cmd.hpp"
+#include "backend/real-clock.hpp"
 #include "lib/diff/tree-mutator.hpp"
+#include "lib/format-obj.hpp"
 //#include "gui/ui-bus.hpp"
 //#include "lib/util.hpp"
 
@@ -49,12 +52,14 @@
 //using std::list;
 //using std::shared_ptr;
 using lib::diff::TreeMutator;
+using util::toString;
 
 
 namespace gui {
 namespace interact {
   
   namespace session = proc::mobject::session;
+  namespace cmd = proc::cmd;
   
   using ctrl::GlobalCtx;
   using ctrl::UiState;
@@ -118,7 +123,8 @@ namespace interact {
   void
   InteractionDirector::saveSnapshot()
   {
-    UNIMPLEMENTED ("issue save snapshot command towards current session");
+    string snapshotID{"snap-" + toString(backend::RealClock::now())};
+    invoke (cmd::session_saveSnapshot, snapshotID);
   }
   
   

src/proc/cmd.hpp

@@ -59,11 +59,9 @@ namespace cmd {
   //using std::shared_ptr;
   
   
+  /* ========= global actions ========= */
   
-  /**
-   * @todo wtf
-   */
-  
+  extern CommandSetup session_saveSnapshot;
   
   
   

src/proc/cmd/session-cmd.cpp

@@ -36,6 +36,7 @@
 
 #include "proc/cmd.hpp"
 #include "proc/control/command-def.hpp"
+#include "proc/mobject/session.hpp"
 //#include "lib/symbol.hpp"
 //#include "lib/format-string.hpp"
 
@@ -50,6 +51,7 @@ namespace proc {
 namespace cmd {
   namespace error = lumiera::error;
   
+  using mobject::Session;
   
   namespace { // implementation helper...
   }//(End) implementation helper
@@ -57,7 +59,24 @@ namespace cmd {
   
   
   
-  /** storage for.... */
+  /** store a snapshot of current session actions and state and UI state.
+   * @param snapshotID a marker to tag the snapshot
+   */
+  COMMAND_DEFINITION (session_saveSnapshot)
+    {
+      def.operation ([](string snapshotID)
+                        {
+                          Session::current.save (snapshotID);
+                        })
+         .captureUndo ([](string snapshotID) -> string
+                        {
+                          return snapshotID;
+                        })
+         .undoOperation ([](string, string oldSnapshot)
+                        {
+                          UNIMPLEMENTED ("how to remove a snapshot from session history");
+                        });
+    };
   
   
   

src/proc/mobject/session.hpp

@@ -189,9 +189,10 @@ namespace mobject {
 
         /** create a complete, serialised representation
          *  of the current session config and contents.
-         *  @todo how to serialise, parameters, return value?
+         * @todo 2017 how actually to serialise, parameters, return value?
+         * @param snapshotID marker to tag the snapshot, like e.g. a timestamp
          */
-        virtual void save ()  =0;
+        virtual void save (string snapshotID)  =0;
         
         /** access to the current session object instance.
          *  This is the sole access path available for clients.

src/proc/mobject/session/sess-manager-impl.cpp

@@ -295,7 +295,7 @@ namespace session {
    *  to several files (master file and edl files)
    */
   void
-  SessManagerImpl::save()
+  SessManagerImpl::save (string stnapshotID)
   {
     UNIMPLEMENTED ("save session (serialised)");
     /////////////////////////////////////////////////TODO: need lock?

src/proc/mobject/session/sess-manager-impl.hpp

@@ -71,13 +71,13 @@ namespace session {
      ~SessManagerImpl() ;
       
       /* ==== SessManager API ==== */
-      virtual void clear()  override;
-      virtual void close()  override;
-      virtual void reset()  override;
-      virtual void load ()  override;
-      virtual void save ()  override;
+      virtual void clear()        override;
+      virtual void close()        override;
+      virtual void reset()        override;
+      virtual void load ()        override;
+      virtual void save (string)  override;
       
-      virtual bool isUp ()  override;
+      virtual bool isUp ()        override;
       
       
     public: