From ce47bfb110dea594fe072c86383910e1334fb5d1 Mon Sep 17 00:00:00 2001
From: Klemen Plestenjak <plestenjak.klemen@gmail.com>
Date: Sat, 2 Dec 2023 14:31:52 +0100
Subject: [PATCH] Defer component mutation

---
 game/systems_input.c | 41 ++++++++++++++++++++++++++++++++++++++---
 1 file changed, 38 insertions(+), 3 deletions(-)

diff --git a/game/systems_input.c b/game/systems_input.c
index bce22fb..2a5e38e 100644
--- a/game/systems_input.c
+++ b/game/systems_input.c
@@ -4,12 +4,16 @@
 #include "pathfinding.h"
 #include <rlImGui.h>
 #include <raymath.h>
+#include <rlgl.h>
 
 Rectangle calculateEntityBounds(Position pos, Size size);
 bool getEntityBounds(ecs_entity_t entity, Position *outPos, Size *outSize, Rectangle *outBounds);
 void pickEntity(BzSpatialGrid *entityGrid, Vector2 point);
 void pickEntities(BzSpatialGrid *entityGrid, Rectangle area);
 
+static void iterateSelectedUnits(ecs_query_t *query, void (*fn)(ecs_entity_t entity, Position *pos, Size *size));
+static void iterRemovePaths(ecs_entity_t entity, Position *pos, Size *size);
+
 void placeUnits(i32 numUnits, f32 unitSpacing, Vector2 start, Vector2 end, BzTileMap *map, Vector2 **outPlaces);
 
 static bool isInputDragged(InputState *input) {
@@ -53,7 +57,7 @@ void updatePlayerInput() {
     Vector2 worldPos = GetScreenToWorld2D(GetMousePosition(), game->camera);
     BzTile tileX = 0, tileY = 0;
     bzTileMapPosToTile(map, worldPos, &tileX, &tileY);
-    i32 selectedUnitCount = ecs_count_id(ECS, UnitSelected);
+    i32 selectedUnitCount = ecs_query_entity_count(input->unitSelectedQuery);
     switch (input->state) {
         case INPUT_NONE:
             if (wasInputDragged(input)) {
@@ -112,13 +116,18 @@ void updatePlayerInput() {
                 BZ_ASSERT(bzArraySize(input->unitPositions) == numUnits);
                 i32 unitPosIdx = 0;
 
-                ecs_iter_t it = ecs_query_iter(ECS, input->unitSelectedQuery);
+                ecs_defer_begin(ECS);
+                iterateSelectedUnits(input->unitSelectedQuery, iterRemovePaths);
+                ecs_defer_end(ECS);
 
+                ecs_iter_t it = ecs_query_iter(ECS, input->unitSelectedQuery);
+                ecs_defer_begin(ECS);
                 while (ecs_iter_next(&it)) {
                     Position *pos = ecs_field(&it, Position, 1);
                     for (i32 i = 0; i < it.count; i++) {
                         ecs_entity_t entity = it.entities[i];
-                        ecs_remove(ECS, entity, Path);
+
+                        fflush(stdout);
 
                         Position target = bzArrayGet(input->unitPositions, unitPosIdx);
                         unitPosIdx++;
@@ -136,9 +145,15 @@ void updatePlayerInput() {
 
                     }
                 }
+                ecs_defer_end(ECS);
             } else if (wasInputClicked(input)) {
+                ecs_defer_begin(ECS);
+                iterateSelectedUnits(input->unitSelectedQuery, iterRemovePaths);
+                ecs_defer_end(ECS);
+
                 ecs_iter_t it = ecs_query_iter(ECS, input->unitSelectedQuery);
 
+                ecs_defer_begin(ECS);
                 while (ecs_iter_next(&it)) {
                     Position *pos = ecs_field(&it, Position, 1);
                     for (i32 i = 0; i < it.count; i++) {
@@ -158,6 +173,7 @@ void updatePlayerInput() {
 
                     }
                 }
+                ecs_defer_end(ECS);
             }
             break;
         case INPUT_SELECTED_OBJECT:
@@ -231,6 +247,7 @@ void drawPlayerInputUI() {
             break;
     }
     ecs_iter_t it = ecs_query_iter(ECS, input->unitSelectedQuery);
+    rlSetLineWidth(2.0f);
     while (ecs_query_next(&it)) {
         Position *pos  = ecs_field(&it, Position, 1);
         Size     *size = ecs_field(&it, Size, 2);
@@ -355,3 +372,21 @@ void placeUnits(i32 numUnits, f32 unitSpacing, Vector2 start, Vector2 end, BzTil
         pos.x += unitSpacing * 2.0f;
     }
 }
+
+static void iterateSelectedUnits(ecs_query_t *query, void (*fn)(ecs_entity_t entity, Position *pos, Size *size)) {
+    ecs_iter_t it = ecs_query_iter(ECS, query);
+    while (ecs_iter_next(&it)) {
+        Position *pos  = ecs_field(&it, Position, 1);
+        Size     *size = ecs_field(&it, Size, 2);
+
+        for (i32 i = 0; i < it.count; i++) {
+            ecs_entity_t entity = it.entities[i];
+
+            fn(entity, pos + i, size + i);
+        }
+    }
+}
+static void iterRemovePaths(ecs_entity_t entity, Position *pos, Size *size) {
+    ecs_remove(ECS, entity, Path);
+}
+