add wml_conditionals support, in addition to wml_actions in lua

src/game_events/conditional_wml.cpp

@@ -17,27 +17,28 @@
  * Implementations of conditional action WML tags.
  */
 
-#include "../global.hpp"
+#include "global.hpp"
 #include "conditional_wml.hpp"
 
-#include "../config.hpp"
-#include "../game_board.hpp"
-#include "../game_data.hpp"
-#include "../log.hpp"
-#include "../recall_list_manager.hpp"
-#include "../resources.hpp"
-#include "../serialization/string_utils.hpp"
-#include "../team.hpp"
-#include "../terrain_filter.hpp"
-#include "../unit.hpp"
-#include "../unit_filter.hpp"
-#include "../unit_map.hpp"
-#include "../unit_types.hpp"
-#include "../util.hpp"
-#include "../variable.hpp"
+#include "config.hpp"
+#include "game_board.hpp"
+#include "game_data.hpp"
+#include "log.hpp"
+#include "recall_list_manager.hpp"
+#include "resources.hpp"
+#include "scripting/game_lua_kernel.hpp"
+#include "serialization/string_utils.hpp"
+#include "team.hpp"
+#include "terrain_filter.hpp"
+#include "unit.hpp"
+#include "unit_filter.hpp"
+#include "unit_map.hpp"
+#include "unit_types.hpp"
+#include "util.hpp"
+#include "variable.hpp"
 
 #include <boost/foreach.hpp>
-
+#include <boost/assign/list_of.hpp>
 
 static lg::log_domain log_engine("engine");
 #define WRN_NG LOG_STREAM(warn, log_engine)
@@ -170,6 +171,23 @@ namespace { // Support functions
 #undef TEST_NUM_ATTR
 #undef TEST_BOL_ATTR
 		}
+
+		vconfig::all_children_iterator cond_end = cond.ordered_end();
+		static const boost::container::flat_set<std::string> hard_coded = boost::assign::list_of("true")("false")("have_unit")("have_location")("variable")
+		("then")("else")("elseif")("not")("and")("or")("do");
+
+		assert(resources::lua_kernel);
+
+		for (vconfig::all_children_iterator it = cond.ordered_begin(); it != cond_end; ++it) {
+			std::string key = it.get_key();
+			if (std::find(hard_coded.begin(), hard_coded.end(), key) == hard_coded.end()) {
+				bool result = resources::lua_kernel->run_wml_conditional(key, it.get_child());
+				if (!result) {
+					return false;
+				}
+			}
+		}
+
 		return true;
 	}
 

src/scripting/game_lua_kernel.cpp

@@ -4172,6 +4172,14 @@ game_lua_kernel::game_lua_kernel(const config &cfg, CVideo * video, game_state &
 	lua_setfield(L, -2, "wml_actions");
 	lua_pop(L, 1);
 
+	// Create the wml_conditionals table.
+	cmd_log_ << "Adding wml_conditionals table...\n";
+
+	lua_getglobal(L, "wesnoth");
+	lua_newtable(L);
+	lua_setfield(L, -2, "wml_conditionals");
+	lua_pop(L, 1);
+
 	// Create the game_events table.
 	cmd_log_ << "Adding game_events table...\n";
 
@@ -4418,6 +4426,33 @@ bool game_lua_kernel::run_wml_action(std::string const &cmd, vconfig const &cfg,
 }
 
 
+/**
+ * Runs a command from an event handler.
+ * @return true if there is a handler for the command.
+ * @note @a cfg should be either volatile or long-lived since the Lua
+ *       code may grab it for an arbitrary long time.
+ */
+bool game_lua_kernel::run_wml_conditional(std::string const &cmd, vconfig const &cfg)
+{
+	lua_State *L = mState;
+
+
+	if (!luaW_getglobal(L, "wesnoth", "wml_conditionals", cmd.c_str(), NULL)) {
+		std::string err_msg = "unknown conditional wml: [";
+		err_msg += cmd;
+		err_msg += "]";
+		luaL_argerror(L, 1, err_msg.c_str());
+	}
+
+	luaW_pushvconfig(L, cfg);
+	luaW_pcall(L, 1, 0, true);
+
+	bool b = luaW_toboolean(L, -1);
+	lua_pop(L, 1);
+	return b;
+}
+
+
 /**
  * Runs a script from a unit filter.
  * The script is an already compiled function given by its name.

src/scripting/game_lua_kernel.hpp

@@ -173,6 +173,7 @@ public:
 	bool run_wml_action(std::string const &, vconfig const &,
 		game_events::queued_event const &);
 	bool run_filter(char const *name, unit const &u);
+	bool run_wml_conditional(std::string const &, vconfig const &);
 
 	virtual void log_error(char const* msg, char const* context = "Lua error");