wb: fix handling of extra_recruit and [filter_recall]

fixes #3100

src/whiteboard/recall.cpp

@@ -34,6 +34,7 @@
 #include "statistics.hpp"
 #include "synced_context.hpp"
 #include "team.hpp"
+#include "units/filter.hpp"
 #include "units/unit.hpp"
 #include "units/animation_component.hpp"
 
@@ -233,7 +234,12 @@ action::error recall::check_validity() const
 		return NOT_ENOUGH_GOLD;
 	}
 	//Check that there is a leader available to recall this unit
-	if(!find_recruiter(team_index(),get_recall_hex())) {
+	bool has_recruiter = any_recruiter(team_index() - 1, get_recall_hex(), [&](unit& leader) {
+		const unit_filter ufilt(vconfig(leader.recall_filter()));
+		return ufilt(*temp_unit_, map_location::null_location());
+	});
+
+	if(!has_recruiter) {
 		return NO_LEADER;
 	}
 

src/whiteboard/recruit.cpp

@@ -207,10 +207,14 @@ action::error recruit::check_validity() const
 		return LOCATION_OCCUPIED;
 	}
 	//Check that unit to recruit is still in side's recruit list
-	//FIXME: look at leaders extra_recruit too.
 	const std::set<std::string>& recruits = resources::gameboard->teams()[team_index()].recruits();
 	if(recruits.find(unit_name_) == recruits.end()) {
-		return UNIT_UNAVAILABLE;
+		bool in_extra_recruit = any_recruiter(team_index() - 1, get_recruit_hex(), [&](unit& leader) {
+			return std::find(leader.recruits().begin(), leader.recruits().end(), unit_name_) != leader.recruits().end();
+		});
+		if (!in_extra_recruit) {
+			return UNIT_UNAVAILABLE;
+		}
 	}
 	//Check that there is still enough gold to recruit this unit
 	if(temp_unit_->cost() > resources::gameboard->teams()[team_index()].gold()) {

src/whiteboard/utility.cpp

@@ -89,6 +89,22 @@ unit* find_recruiter(size_t team_index, const map_location& hex)
 	return nullptr;
 }
 
+bool any_recruiter(int team_num, const map_location& loc, std::function<bool(unit&)> func)
+{
+	if ( !resources::gameboard->map().is_castle(loc) ) {
+		return false;
+	}
+
+	for(unit& u : resources::gameboard->units()) {
+		if(u.can_recruit() && u.side() == team_num && dynamic_cast<game_state&>(*resources::filter_con).can_recruit_on(u, loc)) {
+			if(func(u)) {
+				return true;
+			}
+		}
+	}
+	return false;
+}
+
 unit* future_visible_unit(map_location hex, int viewer_side)
 {
 	future_map planned_unit_map;

src/whiteboard/utility.hpp

@@ -53,6 +53,11 @@ unit_const_ptr find_backup_leader(const unit& leader);
  * @retval nullptr if no such leader has been found
  */
 unit* find_recruiter(size_t team_index, const map_location&);
+/**
+ * executes @a func for each unti of side of @a side_num that can recruit on @a loc.
+ * @a func takes the leader unit and can return true to 'break' the loop
+ */
+bool any_recruiter(int side_num, const map_location& loc, std::function<bool(unit&)> func);
 
 /// Applies the future unit map and @return a pointer to the unit at hex
 /// @retval nullptr if none is visible to the specified viewer side