From daa48e0dce026992d13df55c28cc5518b4331c1e Mon Sep 17 00:00:00 2001
From: Chris Beck <render787@gmail.com>
Date: Sat, 5 Jul 2014 02:21:07 -0400
Subject: [PATCH] add all_matches, first_match fcns to unit_filter, use at
 [object]

---
 src/game_events/action_wml.cpp | 16 ++++++-------
 src/unit_filter.cpp            | 41 ++++++++++++++++++++++++++++++++--
 src/unit_filter.hpp            | 13 +++++++++++
 3 files changed, 60 insertions(+), 10 deletions(-)

diff --git a/src/game_events/action_wml.cpp b/src/game_events/action_wml.cpp
index 6516d04a6468..be820ed2af66 100644
--- a/src/game_events/action_wml.cpp
+++ b/src/game_events/action_wml.cpp
@@ -1410,6 +1410,9 @@ WML_HANDLER_FUNCTION(move_units_fake, /*event_info*/, cfg)
 WML_HANDLER_FUNCTION(object, event_info, cfg)
 {
 	const vconfig & filter = cfg.child("filter");
+	boost::optional<unit_filter> ufilt;
+	if (!filter.null())
+		ufilt = unit_filter(filter, resources::filter_con);
 
 	std::string id = cfg["id"];
 
@@ -1422,13 +1425,10 @@ WML_HANDLER_FUNCTION(object, event_info, cfg)
 	std::string text;
 
 	map_location loc;
-	if(!filter.null()) {
-		const unit_filter ufilt(filter, resources::filter_con);
-		BOOST_FOREACH(const unit &u, *resources::units) {
-			if ( ufilt(u) ) {
-				loc = u.get_location();
-				break;
-			}
+	if(ufilt) {
+		unit_const_ptr u_ptr = ufilt->first_match_on_map();
+		if (u_ptr) {
+			loc = u_ptr->get_location();
 		}
 	}
 
@@ -1440,7 +1440,7 @@ WML_HANDLER_FUNCTION(object, event_info, cfg)
 
 	std::string command_type = "then";
 
-	if ( u != resources::units->end()  &&  (filter.null() || unit_filter(filter, resources::filter_con).matches(*u)) )
+	if ( u != resources::units->end()  &&  (!ufilt || ufilt->matches(*u)) )
 	{
 		///@deprecated This can be removed (and a proper duration=level implemented) after 1.11.2
 		/// Don't forget to remove it from wmllint too!
diff --git a/src/unit_filter.cpp b/src/unit_filter.cpp
index c09668a8034d..c42bc75fa4c4 100644
--- a/src/unit_filter.cpp
+++ b/src/unit_filter.cpp
@@ -59,12 +59,27 @@ static boost::shared_ptr<unit_filter_abstract_impl> construct(const vconfig & vc
 /// Null unit filter is built when the input config is null
 class null_unit_filter_impl : public unit_filter_abstract_impl {
 public:
-	null_unit_filter_impl() {}
+	null_unit_filter_impl(const filter_context & fc) : fc_(fc) {}
 	virtual bool matches(const unit & /*u*/, const map_location & /*loc*/) const {
 		return true;
 	}
+	virtual std::vector<const unit *> all_matches_on_map() const {
+		std::vector<const unit *> ret;
+		BOOST_FOREACH(const unit & u, fc_.get_disp_context().units()) {
+			ret.push_back(&u);
+		}
+		return ret;
+	}
+
+	virtual unit_const_ptr first_match_on_map() const {
+		return fc_.get_disp_context().units().begin().get_shared_ptr();
+	}
+
 
 	virtual ~null_unit_filter_impl() {}
+
+private:
+	const filter_context & fc_;
 };
 
 /// This enum helps to evaluate conditional filters
@@ -220,6 +235,8 @@ class basic_unit_filter_impl : public unit_filter_abstract_impl {
 	}
 
 	virtual bool matches(const unit & u, const map_location & loc) const;
+	virtual std::vector<const unit *> all_matches_on_map() const;
+	virtual unit_const_ptr first_match_on_map() const;
 
 	virtual ~basic_unit_filter_impl() {}
 private:
@@ -277,7 +294,7 @@ class basic_unit_filter_impl : public unit_filter_abstract_impl {
 static boost::shared_ptr<unit_filter_abstract_impl> construct(const vconfig & vcfg, const filter_context & fc, bool flat_tod)
 {
 	if (vcfg.null()) {
-		return boost::make_shared<null_unit_filter_impl> ();
+		return boost::make_shared<null_unit_filter_impl> (fc);
 	}
 	return boost::make_shared<basic_unit_filter_impl>(vcfg, fc, flat_tod);
 	//TODO: Add more efficient implementations for special cases
@@ -580,3 +597,23 @@ bool basic_unit_filter_impl::internal_matches_filter(const unit & u, const map_l
 
 	return true;
 }
+
+std::vector<const unit *> basic_unit_filter_impl::all_matches_on_map() const {
+	std::vector<const unit *> ret;
+	BOOST_FOREACH(const unit & u, fc_.get_disp_context().units()) {
+		if (matches(u, u.get_location())) {
+			ret.push_back(&u);
+		}
+	}
+	return ret;
+}
+
+unit_const_ptr basic_unit_filter_impl::first_match_on_map() const {
+	const unit_map & units = fc_.get_disp_context().units();
+	for(unit_map::const_iterator u = units.begin(); u != units.end(); u++) {
+		if (matches(*u,u->get_location())) {
+			return u.get_shared_ptr();
+		}
+	}
+	return unit_const_ptr();
+}
diff --git a/src/unit_filter.hpp b/src/unit_filter.hpp
index 66c06729cde7..52dca43aff4f 100644
--- a/src/unit_filter.hpp
+++ b/src/unit_filter.hpp
@@ -26,7 +26,10 @@
 #ifndef INCLUDED_UNIT_FILTER_HPP_
 #define INCLUDED_UNIT_FILTER_HPP_
 
+#include "unit_ptr.hpp"
+
 #include <boost/shared_ptr.hpp>
+#include <vector>
 
 class filter_context;
 class unit;
@@ -36,6 +39,8 @@ struct map_location;
 class unit_filter_abstract_impl {
 public:
 	virtual bool matches(const unit & u, const map_location & loc) const = 0;
+	virtual std::vector<const unit*> all_matches_on_map() const = 0;
+	virtual unit_const_ptr first_match_on_map() const = 0;
 	virtual ~unit_filter_abstract_impl() {}
 };
 
@@ -71,6 +76,14 @@ class unit_filter {
 	bool operator()(const unit & u) const {
 		return matches(u);
 	}
+
+	std::vector<const unit *> all_matches_on_map() const {
+		return impl_->all_matches_on_map();
+	}
+
+	unit_const_ptr first_match_on_map() const {
+		return impl_->first_match_on_map();
+	}
 private:
 	boost::shared_ptr<unit_filter_abstract_impl> impl_;
 };