Make basic placing/erasing items undoable

src/scenedit/scen.actions.cpp

@@ -712,12 +712,18 @@ static bool handle_rb_action(location the_point, bool option_hit) {
 stroke_ter_changes_t current_stroke_changes;
 std::string current_stroke_type;
 
+item_changes_t current_items_placed;
+
 void commit_stroke() {
 	if(!current_stroke_changes.empty()){
 		undo_list.add(action_ptr(new aDrawTerrain("Draw Terrain (" + current_stroke_type + ")", current_stroke_changes)));
 		update_edit_menu();
 		current_stroke_changes.clear();
 		current_stroke_type = "";
+	}else if(!current_items_placed.empty()){
+		undo_list.add(action_ptr(new aPlaceEraseItem(current_items_placed.size() > 1 ? "Place Items" : "Place Item", true, current_items_placed)));
+		update_edit_menu();
+		current_items_placed.clear();
 	}
 }
 
@@ -896,16 +902,7 @@ static bool handle_terrain_action(location the_point, bool ctrl_hit) {
 				// If we just placed this item there, forget it
 				if(!mouse_button_held || last_placement != spot_hit) {
 					mouse_button_held = true;
-					auto iter = std::find_if(town->preset_items.begin(), town->preset_items.end(), [](const cTown::cItem& item) {
+					place_item(spot_hit, mode_count, false, false, 100, current_items_placed);
-						return item.code < 0;
-					});
-					if(iter != town->preset_items.end()) {
-						*iter = {spot_hit, mode_count, scenario.scen_items[mode_count]};
-						if(container_there(spot_hit)) iter->contained = true;
-					} else {
-						town->preset_items.push_back({spot_hit, mode_count, scenario.scen_items[mode_count]});
-						if(container_there(spot_hit)) town->preset_items.back().contained = true;
-					}
 					last_placement = spot_hit;
 				}
 				break;
@@ -1154,11 +1151,12 @@ static bool handle_terrain_action(location the_point, bool ctrl_hit) {
 				for(short x = 0; x < town->preset_items.size(); x++)
 					if((spot_hit.x == town->preset_items[x].loc.x) &&
 					   (spot_hit.y == town->preset_items[x].loc.y) && (town->preset_items[x].code >= 0)) {
+
+						undo_list.add(action_ptr(new aPlaceEraseItem("Erase Item", false, x, town->preset_items[x])));
+						update_edit_menu();
 						town->preset_items[x].code = -1;
 						break;
 					}
-				while(!town->preset_items.empty() && town->preset_items.back().code == -1)
-					town->preset_items.pop_back();
 				overall_mode = MODE_DRAWING;
 				break;
 			case MODE_SET_TOWN_START:
@@ -2444,7 +2442,7 @@ void adjust_space(location l, stroke_ter_changes_t& stroke_changes) {
 	}
 }
 
-bool place_item(location spot_hit,short which_item,bool property,bool always,short odds)  {
+bool place_item(location spot_hit,short which_item,bool property,bool always,short odds,std::map<size_t,cTown::cItem>& items_placed) {
 	// odds 0 - 100, with 100 always
 	if((which_item < 0) || (which_item >= scenario.scen_items.size()))
 		return true;
@@ -2462,6 +2460,8 @@ bool place_item(location spot_hit,short which_item,bool property,bool always,sho
 			town->preset_items[x].contained = container_there(spot_hit);
 			town->preset_items[x].property = property;
 			town->preset_items[x].always_there = always;
+			items_placed[x] = town->preset_items[x];
+
 			return true;
 		}
 	}
@@ -2471,6 +2471,7 @@ bool place_item(location spot_hit,short which_item,bool property,bool always,sho
 
 void place_items_in_town() {
 	location l;
+	std::map<size_t, cTown::cItem> items_placed;
 	for(short i = 0; i < town->max_dim; i++)
 		for(short j = 0; j < town->max_dim; j++) {
 			l.x = i;
@@ -2481,7 +2482,7 @@ void place_items_in_town() {
 					for(short x = 0; x < 10; x++)
 						place_item(l,scenario.storage_shortcuts[k].item_num[x],
 								   scenario.storage_shortcuts[k].property,false,
-								   scenario.storage_shortcuts[k].item_odds[x]);
+								   scenario.storage_shortcuts[k].item_odds[x],items_placed);
 				}
 		}
 	draw_terrain();

src/scenedit/scen.actions.hpp

@@ -28,7 +28,7 @@ void adjust_space(location l,stroke_ter_changes_t& stroke_changes);
 void commit_stroke();
 bool is_lava(short x,short y);
 ter_num_t coord_to_ter(short x,short y);
-bool place_item(location spot_hit,short which_item,bool property,bool always,short odds); 
+bool place_item(location spot_hit,short which_item,bool property,bool always,short odds,std::map<size_t,cTown::cItem>& items_placed);
 void place_items_in_town();
 void set_up_start_screen();
 void set_up_main_screen();

src/scenedit/scen.undo.cpp

@@ -16,17 +16,17 @@ extern void start_out_edit();
 extern void redraw_screen();
 extern void set_current_town(int,bool first_restore = false);
 
-cTerrainAction::cTerrainAction(std::string name, short town_num, location where) : cAction(name) {
+cTerrainAction::cTerrainAction(std::string name, short town_num, location where, bool reversed) : cAction(name, reversed) {
 	area.is_town = true;
 	area.town_num = town_num;
 	area.where = where;
 }
-cTerrainAction::cTerrainAction(std::string name, location out_sec, location where) : cAction(name) {
+cTerrainAction::cTerrainAction(std::string name, location out_sec, location where, bool reversed) : cAction(name, reversed) {
 	area.is_town = false;
 	area.out_sec = out_sec;
 	area.where = where;
 }
-cTerrainAction::cTerrainAction(std::string name, location where) : cAction(name) {
+cTerrainAction::cTerrainAction(std::string name, location where, bool reversed) : cAction(name, reversed) {
 	area.is_town = editing_town;
 	// One of these two will be ignored
 	area.town_num = cur_town;
@@ -108,3 +108,29 @@ bool aDrawTerrain::redo_me() {
 	}
 	return true;
 }
+
+aPlaceEraseItem::aPlaceEraseItem(std::string name, bool place, size_t index, cTown::cItem item)
+	: cTerrainAction(name, item.loc, !place)
+	, items({{index, item}})
+{}
+
+aPlaceEraseItem::aPlaceEraseItem(std::string name, bool place, item_changes_t items)
+	: cTerrainAction(name, items.begin()->second.loc, !place)
+	, items(items)
+{}
+
+bool aPlaceEraseItem::undo_me() {
+	auto& town_items = scenario.towns[cur_town]->preset_items;
+	for(auto change : items){
+		town_items[change.first].code = -1;
+	}
+	return true;
+}
+
+bool aPlaceEraseItem::redo_me() {
+	auto& town_items = scenario.towns[cur_town]->preset_items;
+	for(auto change : items){
+		town_items[change.first] = change.second;
+	}
+	return true;
+}

src/scenedit/scen.undo.hpp

@@ -3,6 +3,7 @@
 
 #include "location.hpp"
 #include "tools/undo.hpp"
+#include "scenario/town.hpp"
 
 struct area_ref_t {
 	bool is_town;
@@ -18,13 +19,14 @@ struct ter_change_t {
 };
 
 typedef std::map<location,ter_change_t,loc_compare> stroke_ter_changes_t;
+typedef std::map<size_t, cTown::cItem> item_changes_t;
 
 // Action that modified something in town or outdoor terrain, so we should show the modified area when undoing or redoing
 class cTerrainAction : public cAction {
 public:
-	cTerrainAction(std::string name, short town_num, location where);
+	cTerrainAction(std::string name, short town_num, location where, bool reversed = false);
-	cTerrainAction(std::string name, location out_sec, location where);
+	cTerrainAction(std::string name, location out_sec, location where, bool reversed = false);
-	cTerrainAction(std::string name, location where);
+	cTerrainAction(std::string name, location where, bool reversed = false);
 	void undo();
 	void redo();
 	bool undo_me() = 0;
@@ -58,6 +60,17 @@ private:
 	const stroke_ter_changes_t changes;
 };
 
+/// Action which places or erases item(s) in a town
+class aPlaceEraseItem : public cTerrainAction {
+	bool placed;
+	item_changes_t items;
+	bool undo_me() override;
+	bool redo_me() override;
+public:
+	aPlaceEraseItem(std::string name, bool place, item_changes_t items);
+	aPlaceEraseItem(std::string name, bool place, size_t index, cTown::cItem item);
+};
+
 /// Action which adds a new town to the end of the list, or deletes the last one
 class aCreateDeleteTown : public cAction {
 	bool created;