From a98514e6c9f9ed3dc01d33db943e596d2dc6bd62 Mon Sep 17 00:00:00 2001
From: m-arcuri <124469923+m-arcuri@users.noreply.github.com>
Date: Wed, 30 Oct 2024 20:09:54 -0400
Subject: [PATCH] Prevent grenade purchase if player cannot carry it (#251)

* Prevent grenade purchase if already carrying that type
Only run weapon drop logic if purchased weapon is primary or secondary

* Add cvar checks for grenade inventory limit when buying

* Rewrite logic for grenade ammo cvar checks when buying

---------

Co-authored-by: Alex <mctehkitti@gmail.com>
---
 src/commands.cpp              | 92 +++++++++++++++++++++++++++++++----
 src/cs2_sdk/entity/services.h |  7 +++
 2 files changed, 89 insertions(+), 10 deletions(-)

diff --git a/src/commands.cpp b/src/commands.cpp
index b2b74dc6..cb02c3d0 100644
--- a/src/commands.cpp
+++ b/src/commands.cpp
@@ -103,6 +103,48 @@ bool g_bEnableWeapons = false;
 
 FAKE_BOOL_CVAR(cs2f_weapons_enable, "Whether to enable weapon commands", g_bEnableWeapons, false, false)
 
+int GetGrenadeAmmo(CCSPlayer_WeaponServices* pWeaponServices, WeaponMapEntry_t weaponEntry)
+{
+	if (!pWeaponServices || weaponEntry.iGearSlot != GEAR_SLOT_GRENADES)
+		return -1;
+
+	// TODO: look into molotov vs inc interaction
+	if (strcmp(weaponEntry.szClassName, "weapon_hegrenade") == 0)
+		return pWeaponServices->m_iAmmo[AMMO_OFFSET_HEGRENADE];
+	else if (strcmp(weaponEntry.szClassName, "weapon_molotov") == 0 || strcmp(weaponEntry.szClassName, "weapon_incgrenade") == 0)
+		return pWeaponServices->m_iAmmo[AMMO_OFFSET_MOLOTOV];
+	else if (strcmp(weaponEntry.szClassName, "weapon_decoy") == 0)
+		return pWeaponServices->m_iAmmo[AMMO_OFFSET_DECOY];
+	else if (strcmp(weaponEntry.szClassName, "weapon_flashbang") == 0)
+		return pWeaponServices->m_iAmmo[AMMO_OFFSET_FLASHBANG];
+	else if (strcmp(weaponEntry.szClassName, "weapon_smokegrenade") == 0)
+		return pWeaponServices->m_iAmmo[AMMO_OFFSET_SMOKEGRENADE];
+	else
+		return -1;
+}
+
+int GetGrenadeAmmoTotal(CCSPlayer_WeaponServices* pWeaponServices)
+{
+	if(!pWeaponServices)
+		return -1;
+	
+	int grenadeAmmoOffsets[] = {
+		AMMO_OFFSET_HEGRENADE,
+		AMMO_OFFSET_FLASHBANG,
+		AMMO_OFFSET_SMOKEGRENADE,
+		AMMO_OFFSET_DECOY,
+		AMMO_OFFSET_MOLOTOV,
+	};
+
+	int totalGrenades = 0;
+	for (int i = 0; i < (sizeof(grenadeAmmoOffsets) / sizeof(int)); i++)
+	{
+		totalGrenades += pWeaponServices->m_iAmmo[grenadeAmmoOffsets[i]];
+	}
+	
+	return totalGrenades;
+}
+
 void ParseWeaponCommand(const CCommand& args, CCSPlayerController* player)
 {
 	if (!g_bEnableWeapons || !player || !player->m_hPawn())
@@ -159,6 +201,33 @@ void ParseWeaponCommand(const CCommand& args, CCSPlayerController* player)
 		return;
 	}
 
+	if (weaponEntry.iGearSlot == GEAR_SLOT_GRENADES)
+	{
+		CUtlVector<CHandle<CBasePlayerWeapon>>* weapons = pWeaponServices->m_hMyWeapons();
+
+		// CONVAR_TODO
+		ConVar* cvar = g_pCVar->GetConVar(g_pCVar->FindConVar("ammo_grenade_limit_default"));
+		// HACK: values is actually the cvar value itself, hence this ugly cast.
+		int iGrenadeLimitDefault = *(int*)&cvar->values;
+		cvar = g_pCVar->GetConVar(g_pCVar->FindConVar("ammo_grenade_limit_total"));
+		int iGrenadeLimitTotal = *(int*)&cvar->values;
+
+		int iMatchingGrenades = GetGrenadeAmmo(pWeaponServices, weaponEntry);
+		int iTotalGrenades = GetGrenadeAmmoTotal(pWeaponServices);
+
+		if (iMatchingGrenades >= iGrenadeLimitDefault)
+		{
+			ClientPrint(player, HUD_PRINTTALK, CHAT_PREFIX"You cannot carry any more %ss (Max %i)", weaponEntry.szWeaponName, iGrenadeLimitDefault);
+			return;
+		}
+
+		if (iTotalGrenades >= iGrenadeLimitTotal)
+		{
+			ClientPrint(player, HUD_PRINTTALK, CHAT_PREFIX"You cannot carry any more grenades (Max %i)", iGrenadeLimitTotal);
+			return;
+		}
+	}
+
 	if (weaponEntry.maxAmount)
 	{
 		CUtlVector<WeaponPurchaseCount_t>* weaponPurchases = pPawn->m_pActionTrackingServices->m_weaponPurchasesThisRound().m_weaponPurchases;
@@ -190,19 +259,22 @@ void ParseWeaponCommand(const CCommand& args, CCSPlayerController* player)
 		}
 	}
 
-	CUtlVector<CHandle<CBasePlayerWeapon>>* weapons = pWeaponServices->m_hMyWeapons();
-
-	FOR_EACH_VEC(*weapons, i)
+	if (weaponEntry.iGearSlot == GEAR_SLOT_RIFLE || weaponEntry.iGearSlot == GEAR_SLOT_PISTOL)
 	{
-		CBasePlayerWeapon* weapon = (*weapons)[i].Get();
+		CUtlVector<CHandle<CBasePlayerWeapon>>* weapons = pWeaponServices->m_hMyWeapons();
 
-		if (!weapon)
-			continue;
-
-		if (weapon->GetWeaponVData()->m_GearSlot() == weaponEntry.iGearSlot && (weaponEntry.iGearSlot == GEAR_SLOT_RIFLE || weaponEntry.iGearSlot == GEAR_SLOT_PISTOL))
+		FOR_EACH_VEC(*weapons, i)
 		{
-			pWeaponServices->DropWeapon(weapon);
-			break;
+			CBasePlayerWeapon* weapon = (*weapons)[i].Get();
+
+			if (!weapon)
+				continue;
+
+			if (weapon->GetWeaponVData()->m_GearSlot() == weaponEntry.iGearSlot)
+			{
+				pWeaponServices->DropWeapon(weapon);
+				break;
+			}
 		}
 	}
 
diff --git a/src/cs2_sdk/entity/services.h b/src/cs2_sdk/entity/services.h
index 6c0ea436..74825e61 100644
--- a/src/cs2_sdk/entity/services.h
+++ b/src/cs2_sdk/entity/services.h
@@ -23,6 +23,12 @@
 #include <entity/ccsweaponbase.h>
 #include <entity/ccsplayerpawn.h>
 
+#define AMMO_OFFSET_HEGRENADE		13
+#define AMMO_OFFSET_FLASHBANG		14
+#define AMMO_OFFSET_SMOKEGRENADE	15
+#define AMMO_OFFSET_MOLOTOV			16
+#define AMMO_OFFSET_DECOY			17
+
 class CBaseEntity;
 
 struct CSPerRoundStats_t
@@ -110,6 +116,7 @@ class CPlayer_WeaponServices : public CPlayerPawnComponent
 
 	SCHEMA_FIELD_POINTER(CUtlVector<CHandle<CBasePlayerWeapon>>, m_hMyWeapons)
 	SCHEMA_FIELD(CHandle<CBasePlayerWeapon>, m_hActiveWeapon)
+	SCHEMA_FIELD_POINTER(uint16_t, m_iAmmo)
 };
 
 class CCSPlayer_WeaponServices : public CPlayer_WeaponServices