Big update.

src/strategy/actions/GreetAction.cpp

@@ -0,0 +1,42 @@
+/*
+ * Copyright (C) 2016+ AzerothCore <www.azerothcore.org>, released under GNU GPL v2 license, you may redistribute it and/or modify it under version 2 of the License, or (at your option), any later version.
+ */
+
+#include "GreetAction.h"
+#include "Event.h"
+#include "Playerbots.h"
+
+GreetAction::GreetAction(PlayerbotAI* botAI) : Action(botAI, "greet")
+{
+}
+
+bool GreetAction::Execute(Event event)
+{
+    ObjectGuid guid = AI_VALUE(ObjectGuid, "new player nearby");
+    if (!guid || !guid.IsPlayer())
+        return false;
+
+    Player* player = dynamic_cast<Player*>(botAI->GetUnit(guid));
+    if (!player)
+        return false;
+
+    if (!bot->HasInArc(CAST_ANGLE_IN_FRONT, player, sPlayerbotAIConfig->sightDistance))
+        bot->SetFacingToObject(player);
+
+    ObjectGuid oldSel = bot->GetTarget();
+    bot->SetTarget(guid);
+    //bot->HandleEmote(EMOTE_ONESHOT_WAVE);
+    botAI->PlayEmote(TEXT_EMOTE_HELLO);
+    bot->SetTarget(oldSel);
+
+    GuidSet& alreadySeenPlayers = botAI->GetAiObjectContext()->GetValue<GuidSet&>("already seen players")->Get();
+    alreadySeenPlayers.insert(guid);
+
+    GuidVector nearestPlayers = botAI->GetAiObjectContext()->GetValue<GuidVector>("nearest friendly players")->Get();
+    for (ObjectGuid const guid : nearestPlayers)
+    {
+        alreadySeenPlayers.insert(guid);
+    }
+
+    return true;
+}