Merge pull request 'New event fo begin casting' (#12) from Mats391/nampower:BeginCastEvent into master

Reviewed-on: https://gitea.com/avitasia/nampower/pulls/12

EVENTS.md

@@ -7,6 +7,7 @@ For custom Lua functions, see [SCRIPTS.md](SCRIPTS.md). For general usage inform
 ## Table of Contents
 - [SPELL_QUEUE_EVENT](#spell_queue_event)
 - [SPELL_CAST_EVENT](#spell_cast_event)
+- [SPELL_BEGIN_CAST_EVENT](#spell_begin_cast_event)
 - [SPELL_DAMAGE_EVENT_SELF and SPELL_DAMAGE_EVENT_OTHER](#spell_damage_event_self-and-spell_damage_event_other)
 - [Buff/Debuff Events](#buffdebuff-events)
 - [AURA_CAST_ON_SELF and AURA_CAST_ON_OTHER](#aura_cast_on_self-and-aura_cast_on_other)
@@ -90,6 +91,23 @@ Cursive:RegisterEvent("SPELL_CAST_EVENT", function(success, spellId, castType, t
 end);
 ```
 
+### SPELL_BEGIN_CAST_EVENT
+Event you can register in game to get updates when the clien is about to attempt casting a spell. At this stage the spell is ready and has a valid target, but the spell cast might still be rejected based on line of sight or other factors.
+
+The event is `SPELL_BEGIN_CAST_EVENT` and has 2 parameters:
+1.  int spellId
+2.  string targetGuid - guid string like "0xF5300000000000A5"
+
+targetGuid will be “0x0000000000000000” if the spell requires no target
+
+Example (uses ace RegisterEvent):
+```
+Cursive:RegisterEvent("SPELL_BEING_CAST_EVENT", function(spellId, targetGuid)
+	print(spellId)
+	print(targetGuid)
+end);
+```
+
 ### SPELL_DAMAGE_EVENT_SELF and SPELL_DAMAGE_EVENT_OTHER
 New events you can register in game to get updates whenever spell damage occurs. SPELL_DAMAGE_EVENT_SELF will only trigger for damage you deal, while SPELL_DAMAGE_EVENT_OTHER will only trigger for damage dealt by others.
 

nampower/game.hpp

@@ -1443,6 +1443,8 @@ namespace game {
 
         AURA_CAST_ON_SELF = 560,
         AURA_CAST_ON_OTHER = 561,
+        
+        SPELL_BEGIN_CAST_EVENT = 562,
     };
 
     enum TypeMask {

nampower/main.cpp

@@ -1332,6 +1332,9 @@ namespace Nampower {
         char SPELL_DAMAGE_EVENT_OTHER[] = "SPELL_DAMAGE_EVENT_OTHER";
         addCustomEvent(game::SPELL_DAMAGE_EVENT_OTHER, SPELL_DAMAGE_EVENT_OTHER);
 
+        char SPELL_BEGIN_CAST_EVENT[] = "SPELL_BEGIN_CAST_EVENT";
+        addCustomEvent(game::SPELL_BEGIN_CAST_EVENT, SPELL_BEGIN_CAST_EVENT);
+
         char DEBUFF_ADDED_SELF[] = "DEBUFF_ADDED_SELF";
         addCustomEvent(game::DEBUFF_ADDED_SELF, DEBUFF_ADDED_SELF);
 

nampower/spellcast.cpp

@@ -107,6 +107,21 @@ namespace Nampower {
         }
     }
 
+    void
+    TriggerSpellBeginCastEvent(uint32_t spellId, std::uint64_t guid) {
+        char format[] = "%d%s";
+        char *guidStr = new char[21]; // 2 for 0x prefix, 18 for the number, and 1 for '\0'
+        std::snprintf(guidStr, 21, "0x%016llX", static_cast<unsigned long long>(guid));
+
+        ((int (__cdecl *)(int, char *, uint32_t, char *)) Offsets::SignalEventParam)(
+         game::SPELL_BEGIN_CAST_EVENT, // SPELL_BEGIN_CAST_EVENT event we are adding
+         format,
+         spellId,
+         guidStr);
+
+        delete[] guidStr;
+    }
+
     bool Spell_C_TargetSpellHook(hadesmem::PatchDetourBase *detour,
                                  uint32_t *player,
                                  uint32_t *spellId,
@@ -236,6 +251,9 @@ namespace Nampower {
         }
 
         gLastCastData.startTimeMs = currentTime;
+
+        
+        TriggerSpellBeginCastEvent(cast->spellId, cast->unitTarget);
     }
 
     void CastQueuedNonGcdSpell() {
@@ -1073,6 +1091,7 @@ namespace Nampower {
     }
 
     void SendCastHook(hadesmem::PatchDetourBase *detour, game::SpellCast *cast, char unk) {
+
         auto const sendCast = detour->GetTrampolineT<SendCastT>();
         sendCast(cast, unk);