Enhancement - Hooks

- Added Lua copyright notice to the version command.
- Added Lua copyright details to API.cpp, which is the only file that
  interacts with Lua.
- Added hook-type detection.
- Added a hook-type calling mechanism in Hooks.
- Implemented the post-start and pre-exit event triggers.
- Context::initialize now calls Hooks::initialize, which in turn calls
  API::initialize.  We have liftoff!

src/API.cpp

@@ -23,6 +23,28 @@
 //     02110-1301
 //     USA
 //
+// -------------
+//
+// Copyright © 1994–2008 Lua.org, PUC-Rio.
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+// 
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+// 
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+// SOFTWARE.
+//
 ////////////////////////////////////////////////////////////////////////////////
 
 #include "API.h"
@@ -389,7 +411,7 @@ void API::initialize ()
 {
   // Initialize Lua.
   L = lua_open ();
-  luaL_openlibs (L);
+  luaL_openlibs (L);  // TODO Error handling
 
   // Register all the API functions in Lua global space.
   lua_pushcfunction (L, api_task_version);               lua_setglobal (L, "task_version");

src/Context.cpp

@@ -83,6 +83,11 @@ void Context::initialize (int argc, char** argv)
   }
 
   initialize ();
+
+  // Hook system init, plus post-start event occurring at the first possible
+  // moment after hook initialization.
+  hooks.initialize ();
+  hooks.trigger ("post-start");
 }
 
 ////////////////////////////////////////////////////////////////////////////////
@@ -180,6 +185,7 @@ int Context::run ()
     else
       std::cout << *f << std::endl;
 
+  hooks.trigger ("pre-exit");
   return rc;
 }
 

src/Hooks.cpp

@@ -25,6 +25,7 @@
 //
 ////////////////////////////////////////////////////////////////////////////////
 
+#include <iostream>
 #include "Hooks.h"
 
 ////////////////////////////////////////////////////////////////////////////////
@@ -38,3 +39,90 @@ Hooks::~Hooks ()
 }
 
 ////////////////////////////////////////////////////////////////////////////////
+void Hooks::initialize ()
+{
+  api.initialize ();
+}
+
+////////////////////////////////////////////////////////////////////////////////
+bool Hooks::trigger (const std::string& event)
+{
+  // TODO Look up scripts/functions hooking this event.
+  // TODO Load the scripts if necessary.
+
+  // TODO Call each function.
+  std::string type;
+  if (eventType (event, type))
+  {
+         if (type == "program") return triggerProgramEvent (event);
+    else if (type == "list")    return triggerListEvent    (event);
+    else if (type == "task")    return triggerTaskEvent    (event);
+    else if (type == "field")   return triggerFieldEvent   (event);
+  }
+  else
+    throw std::string ("Unrecognized hook event '") + event + "'";
+
+  return false;
+}
+
+////////////////////////////////////////////////////////////////////////////////
+bool Hooks::eventType (const std::string& event, std::string& type)
+{
+  if (event == "post-start" ||
+      event == "pre-exit")
+  {
+    type = "program";
+    return true;
+  }
+  else if (event == "?")
+  {
+    type = "list";
+    return true;
+  }
+  else if (event == "?")
+  {
+    type = "task";
+    return true;
+  }
+  else if (event == "?")
+  {
+    type = "field";
+    return true;
+  }
+
+  return false;
+}
+
+////////////////////////////////////////////////////////////////////////////////
+bool Hooks::triggerProgramEvent (const std::string& event)
+{
+  std::cout << "Hooks::triggerProgramEvent " << event << std::endl;
+
+  // TODO Is this event hooked?
+  // TODO Is the associated script loaded?
+  // TODO Call the function
+  return false;
+}
+
+////////////////////////////////////////////////////////////////////////////////
+bool Hooks::triggerListEvent (const std::string& event)
+{
+  std::cout << "Hooks::triggerListEvent " << event << std::endl;
+  return false;
+}
+
+////////////////////////////////////////////////////////////////////////////////
+bool Hooks::triggerTaskEvent (const std::string& event)
+{
+  std::cout << "Hooks::triggerTaskEvent " << event << std::endl;
+  return false;
+}
+
+////////////////////////////////////////////////////////////////////////////////
+bool Hooks::triggerFieldEvent (const std::string& event)
+{
+  std::cout << "Hooks::triggerFieldEvent " << event << std::endl;
+  return false;
+}
+
+////////////////////////////////////////////////////////////////////////////////

src/Hooks.h

@@ -27,16 +27,31 @@
 #ifndef INCLUDED_HOOKS
 #define INCLUDED_HOOKS
 
+#include <vector>
+#include <string>
+#include "API.h"
+
 class Hooks
 {
 public:
-  Hooks ();                      // Default constructor
-  ~Hooks ();                     // Destructor
+  Hooks ();                        // Default constructor
+  ~Hooks ();                       // Destructor
+  Hooks (const Hooks&);            // Deliberately unimplemented
+  Hooks& operator= (const Hooks&); // Deliberately unimplemented
 
-  Hooks (const Hooks&);
-  Hooks& operator= (const Hooks&);
+  void initialize ();
+  bool trigger (const std::string&);
+  bool eventType (const std::string&, std::string&);
 
 private:
+  bool triggerProgramEvent (const std::string&);
+  bool triggerListEvent (const std::string&);
+  bool triggerTaskEvent (const std::string&);
+  bool triggerFieldEvent (const std::string&);
+
+private:
+  API api;
+  std::vector <std::string> scripts;
 };
 
 #endif

src/command.cpp

@@ -490,8 +490,12 @@ int handleVersion (std::string &outs)
 #endif
 
       << std::endl
-      << "Copyright (C) 2006 - 2010, P. Beckingham, F. Hernandez."
+      << "Copyright (C) 2006 - 2010 P. Beckingham, F. Hernandez."
       << std::endl
+#ifdef HAVE_LIBLUA
+      << "Portions of this software Copyright (C) 1994 – 2008 Lua.org, PUC-Rio."
+      << std::endl
+#endif
       << disclaimer.render ()
       << link.render ()
       << std::endl;