From 5399b584dd0f47efa3f5ac151257fb3e1cd737da Mon Sep 17 00:00:00 2001
From: Mergul <wismerchil@interia.eu>
Date: Fri, 6 Mar 2020 10:12:52 +0100
Subject: [PATCH] -IDManager reserve EntityID(0) as empty -fixed bug with
 events called on destroyed entities (crash) -don't call event on system for
 unsupported entity -added "entity_id" property to EntitiesData

---
 source/ecs/id_manager.d | 27 ++++++++++++++++++++-------
 source/ecs/manager.d    | 19 ++++++++++++++++---
 tests/tests.d           |  8 ++++++++
 3 files changed, 44 insertions(+), 10 deletions(-)

diff --git a/source/ecs/id_manager.d b/source/ecs/id_manager.d
index ebd7679..04cc360 100644
--- a/source/ecs/id_manager.d
+++ b/source/ecs/id_manager.d
@@ -136,7 +136,9 @@ begin:
     */
     export bool isExist(EntityID id) nothrow @nogc
     {
+        if(id.id >= m_ids_array.length)return false;
         Data* data = &m_ids_array[id.id];
+        if(data.entity is null)return false;
         return data.counter == id.counter;
     }
 
@@ -151,6 +153,9 @@ begin:
 
         add_mutex = Mallocator.make!Mutex();
         add_mutex.initialize();
+
+        getNewID();
+        optimize();
     }
 
     void deinitialize() @trusted @nogc nothrow
@@ -243,23 +248,31 @@ private:
 unittest
 {
     IDManager manager;
+    manager.initialize();
     EntityID id1 = manager.getNewID();
     EntityID id2 = manager.getNewID();
     EntityID id3 = manager.getNewID();
 
-    assert(id1 == EntityID(0, 1));
-    assert(id2 == EntityID(1, 1));
-    assert(id3 == EntityID(2, 1));
+    assert(id1 == EntityID(1, 0));
+    assert(id2 == EntityID(2, 0));
+    assert(id3 == EntityID(3, 0));
 
+    manager.optimize();
     manager.releaseID(id2);
     manager.releaseID(id1);
 
     id2 = manager.getNewID();
     id1 = manager.getNewID();
 
-    assert(id1 == EntityID(1, 2));
-    assert(id2 == EntityID(0, 2));
-    assert(id3 == EntityID(2, 1));
+    Entity e;
+    e.id = id3;
+    manager.update(e);
+
+    assert(id1 == EntityID(2, 1));
+    assert(id2 == EntityID(1, 1));
+    assert(id3 == EntityID(3, 0));
     assert(manager.isExist(id3));
-    assert(!manager.isExist(EntityID(0, 1)));
+    assert(!manager.isExist(EntityID(1, 0)));
+    assert(!manager.isExist(EntityID(0, 0)));
+    manager.deinitialize();
 }
diff --git a/source/ecs/manager.d b/source/ecs/manager.d
index 7c89b71..27eaa40 100644
--- a/source/ecs/manager.d
+++ b/source/ecs/manager.d
@@ -542,7 +542,7 @@ export struct EntityManager
             foreach (member; __traits(allMembers, Sys.EntitiesData))
             {
                 alias MemberType = typeof(__traits(getMember, Sys.EntitiesData, member));
-                if (member == "length" || is(MemberType == Entity[])
+                if (member == "length" || member == "thread_id" || is(MemberType == Entity[])
                         || is(MemberType == const(Entity)[]))
                 {
                     if (is(MemberType == Entity[]) || is(MemberType == const(Entity)[]))
@@ -648,6 +648,13 @@ export struct EntityManager
                     static assert(MemberType.sizeof > 1,
                             "EntitiesData 'length' member can't be byte or ubyte.");
                 }
+                else static if(member == "thread_id")
+                {
+                    static assert(isIntegral!(MemberType),
+                            "EntitiesData 'thread_id' member must be integral type.");
+                    static assert(MemberType.sizeof > 1,
+                            "EntitiesData 'thread_id' member can't be byte or ubyte.");
+                }
                 else static if (!(isArray!(MemberType)))
                     static assert(0, "EntitiesData members should be arrays of elements!");
             }
@@ -703,6 +710,11 @@ export struct EntityManager
             {
                 input_data.length = cast(typeof(input_data.length))(entities_count - offset);
             }
+            
+            static if (hasMember!(Sys.EntitiesData, "thread_id"))
+            {
+                input_data.thread_id = cast(typeof(input_data.thread_id))threadID();
+            }
 
             static foreach (iii, comp_info; components_info.req)
             {
@@ -2378,9 +2390,9 @@ export struct EntityManager
                     {
                         EventCallData call_data;
                         void* event_pointer = cast(void*) block + event.data_offset;
-                        call_data.event = event_pointer;
                         foreach (j; 0 .. block.count)
                         {
+                            call_data.event = event_pointer;
                             EntityID entity_id = *cast(EntityID*) event_pointer;
                             Entity* entity = id_manager.getEntityPointer(entity_id);
                             if (entity)
@@ -2390,6 +2402,7 @@ export struct EntityManager
 
                                 foreach (caller; events[i].callers)
                                 {
+                                    if(call_data.block.type_info.systems[caller.system.m_id] == false)continue;
                                     call_data.system_pointer = caller.system.m_system_pointer;
                                     (cast(void function(
                                             ref EventCallData) nothrow @nogc) caller.callback)(
@@ -2412,9 +2425,9 @@ export struct EntityManager
     {
         id_manager.optimize();
         updateBlocks();
-        removeEntities();
         changeEntities();
         updateEvents();
+        removeEntities();
         event_manager.clearEvents();
     }
 
diff --git a/tests/tests.d b/tests/tests.d
index 9f432fa..3ff9d00 100644
--- a/tests/tests.d
+++ b/tests/tests.d
@@ -515,6 +515,14 @@ struct ExternalUpdateCallTest
 	}
 }
 
+version(unittest)
+{
+	void main()
+	{
+
+	}
+}
+else:
 extern(C) int main()
 {