From 19687b9f88fca07efa70568941feba96a99ed13f Mon Sep 17 00:00:00 2001
From: Mergul <wismerchil@interia.eu>
Date: Sat, 4 Apr 2020 13:58:31 +0200
Subject: [PATCH] -fixed critical bug with adding components -some fixes -minor
 optimization -added debug assert test

---
 source/ecs/core.d    |  6 +++---
 source/ecs/manager.d | 42 ++++++++++++++++++++++++++----------------
 2 files changed, 29 insertions(+), 19 deletions(-)

diff --git a/source/ecs/core.d b/source/ecs/core.d
index dde39a5..91c9065 100644
--- a/source/ecs/core.d
+++ b/source/ecs/core.d
@@ -45,7 +45,7 @@ static struct ECS
 	*/
 	mixin template System(uint jobs_count = 32)
 	{
-		__gshared ushort system_id;
+		__gshared ushort system_id = ushort.max;
 		uint __ecs_jobs_count = jobs_count;
 	}
 
@@ -54,7 +54,7 @@ static struct ECS
 	*/
 	mixin template Component()
 	{
-		__gshared ushort component_id;
+		__gshared ushort component_id = ushort.max;
 	}
 
 	/************************************************************************************************************************
@@ -62,7 +62,7 @@ static struct ECS
 	*/
     mixin template Event()
 	{
-		__gshared ushort event_id;
+		__gshared ushort event_id = ushort.max;
 		EntityID entity_id;
 	}
 
diff --git a/source/ecs/manager.d b/source/ecs/manager.d
index ae94cf7..0e91095 100644
--- a/source/ecs/manager.d
+++ b/source/ecs/manager.d
@@ -770,13 +770,15 @@ export struct EntityManager
         else
             enum OnUpdateOverloadNum = -1;
         //enum HasOnUpdate = (hasMember!(Sys, "onUpdate") && checkOnUpdateParams());
+        enum IsEmpty = components_info.req.length == 0 && components_info.optional.length == 0
+            && components_info.excluded.length == 0 && components_info.entites_array.length == 0;
 
-        static if (components_info.req.length == 0 && components_info.optional.length == 0)
+        static if (IsEmpty)
             system.m_empty = true;
 
         static if (OnUpdateOverloadNum != -1)
         {
-            static if (components_info.req.length != 0 || components_info.optional.length != 0)
+            static if (!IsEmpty)
             {
                 static void callUpdate(ref CallData data)
                 {
@@ -972,6 +974,8 @@ export struct EntityManager
     */
     export System* getSystem(ushort id) nothrow @nogc
     {
+        if (id >= systems.length)
+            return null;
         return &systems[id];
     }
 
@@ -980,6 +984,8 @@ export struct EntityManager
     */
     Sys* getSystem(Sys)() nothrow @nogc
     {
+        if (Sys.system_id >= systems.length)
+            return null;
         return cast(Sys*) systems[Sys.system_id].m_system_pointer;
     }
 
@@ -1404,6 +1410,7 @@ export struct EntityManager
             uint j = 1;
             foreach (i; 1 .. ids.length)
             {
+                assert(ids[i] != ushort.max);
                 if (ids[i] != ids[j - 1])
                 {
                     ids[j] = ids[i];
@@ -1500,9 +1507,10 @@ export struct EntityManager
             }
 
             info.comp_add_info = Mallocator.makeArray!(EntityInfo*)(instance.components.length);
-            info.comp_rem_info = Mallocator.makeArray!(EntityInfo*)(instance.components.length, info);
+            info.comp_rem_info = Mallocator.makeArray!(EntityInfo*)(instance.components.length,
+                    info);
 
-            foreach(comp; info.components)
+            foreach (comp; info.components)
             {
                 info.comp_add_info[comp] = info;
                 info.comp_rem_info[comp] = null;
@@ -1772,17 +1780,18 @@ export struct EntityManager
         EntityInfo* info = block.type_info;
 
         //remove non-existing components
-        uint num = cast(uint)del_ids.length;
-        foreach_reverse(i; 0 .. num)
+        uint num = cast(uint) del_ids.length;
+        foreach_reverse (i; 0 .. num)
         {
-            if(info.deltas.length <= del_ids[i] || info.deltas[del_ids[i]] == 0)
+            if (info.deltas.length <= del_ids[i] || info.deltas[del_ids[i]] == 0)
             {
                 num--;
                 del_ids[i] = del_ids[num];
             }
         }
-        
-        if(num == 0)return;
+
+        if (num == 0)
+            return;
         del_ids = del_ids[0 .. num];
 
         //sort components
@@ -1883,16 +1892,17 @@ export struct EntityManager
         EntitiesBlock* block = getMetaData(entity);
         EntityInfo* info = block.type_info;
 
-        foreach_reverse(i; 0 .. num)
+        foreach_reverse (i; 0 .. num)
         {
-            if(info.deltas.length > new_ids[i] && info.deltas[new_ids[i]] != 0)
+            if (info.deltas.length > new_ids[i] && info.deltas[new_ids[i]] != 0)
             {
                 num--;
                 new_ids[i] = new_ids[num];
             }
         }
-        
-        if(num == 0)return;
+
+        if (num == 0)
+            return;
         new_ids = new_ids[0 .. num];
 
         foreach (int i; 0 .. num)
@@ -1924,7 +1934,7 @@ export struct EntityManager
         {
             new_info = new_info.getNewInfoAdd(id);
         }
-        
+
         assert(new_info != info);
         /*if (new_info == info)
             return;*/
@@ -2825,7 +2835,7 @@ export struct EntityManager
                     foreach (comp2; components[len - 1 .. $])
                     {
                         ids[len++] = comp2;
-                    }  
+                    }
                     break;
                 }
             }
@@ -2834,7 +2844,7 @@ export struct EntityManager
 
             assert(len == components.length + 1);
 
-            EntityInfo* new_info = instance.getEntityInfo(ids);//[0 .. len]);
+            EntityInfo* new_info = instance.getEntityInfo(ids);
 
             comp_add_info[id] = new_info;
             return new_info;