From bd7e78ab94bc0480942bb75c91ba893ca6f9dafe Mon Sep 17 00:00:00 2001
From: Marco Cawthorne <marco@vera-visions.com>
Date: Mon, 22 Apr 2024 21:47:02 -0700
Subject: [PATCH] NSNavAI: Inventory management functions.

---
 src/shared/NSNavAI.h  |   5 ++
 src/shared/NSNavAI.qc | 108 ++++++++++++++++++++++++++++++++++++++++++
 src/shared/defs.h     |   2 +-
 3 files changed, 114 insertions(+), 1 deletion(-)

diff --git a/src/shared/NSNavAI.h b/src/shared/NSNavAI.h
index dbebd1ba..5e8354ab 100644
--- a/src/shared/NSNavAI.h
+++ b/src/shared/NSNavAI.h
@@ -78,6 +78,10 @@ public:
 	nonvirtual bool GiveItem(string);
 	/** Removes a named NSItem from the inventory Returns `false` when impossible. */
 	nonvirtual bool RemoveItem(string);
+	/** Adds the specified NSItem to the inventory. Returns `false` when impossible. */
+	nonvirtual bool AddItem(NSItem);
+	/** Returns `true` or `false` depending on if the entity has the named item. */
+	nonvirtual bool HasItem(string);
 
 #ifdef SERVER
 	/* overrides */
@@ -135,4 +139,5 @@ private:
 
 	/* These are defined in side defs\*.def, ammo_types and ammo_names */
 	int m_iAmmoTypes[MAX_AMMO_TYPES];
+	NSItem m_itemList;
 };
diff --git a/src/shared/NSNavAI.qc b/src/shared/NSNavAI.qc
index fa607b69..bad2208d 100644
--- a/src/shared/NSNavAI.qc
+++ b/src/shared/NSNavAI.qc
@@ -526,14 +526,122 @@ NSNavAI::UseAmmo(int ammoType, int ammoAmount)
 	return (true);
 }
 
+bool
+NSNavAI::HasItem(string itemName)
+{
+	NSItem linkedList = __NULL__;
+
+	/* we do not have an item. */
+	if (!m_itemList) {
+		return (false);
+	}
+
+	/* since we have something in the inventory, start there */
+	linkedList = m_itemList;
+
+	/* iterate through the inventory, then figure out if we already have it*/
+	while (linkedList) {
+		/* we already have the item. */
+		if (linkedList.classname == itemName) {
+			return (true);
+		}
+
+		linkedList = linkedList.chain;
+	}
+
+	return (false);
+}
+
 bool
 NSNavAI::GiveItem(string itemName)
 {
+#ifdef SERVER
+	NSItem linkedList = __NULL__;
+	NSItem lastItem = __NULL__;
+
+	/* we do not have an item yet. */
+	if (!m_itemList) {
+		m_itemList = (NSItem)Entity_CreateClass(itemName);
+		return (true);
+	}
+
+	/* since we have something in the inventory, start there */
+	linkedList = m_itemList;
+
+	/* iterate through the inventory, then figure out if we already have it*/
+	while (linkedList) {
+		/* we already have the item. */
+		if (linkedList.classname == itemName) {
+			return (false);
+		}
+
+		lastItem = linkedList;
+		linkedList = linkedList.chain;
+	}
+
+	/* add it to the back of the chain, so it's part of our inventory. */
+	if (lastItem && linkedList == __NULL__) {
+		NSItem newItem = (NSItem)Entity_CreateClass(itemName);
+		lastItem.chain = newItem;
+	}
+
+	return (true);
+#else
 	return (false);
+#endif
 }
 
 bool
 NSNavAI::RemoveItem(string itemName)
+{
+#ifdef SERVER
+	NSItem linkedList = __NULL__;
+	NSItem frontItem = __NULL__;
+	NSItem lastItem = __NULL__;
+	NSItem itemToRemove = __NULL__;
+	bool removeItem = false;
+
+	/* we posess nothing. auto return false. */
+	if (!m_itemList) {
+		return (false);
+	}
+
+	/* since we have something in the inventory, start there */
+	linkedList = m_itemList;
+
+	/* iterate through the inventory, then figure out if we already have it*/
+	while (linkedList) {
+		/* found the item, mark as needing to be removed */
+		if (linkedList.classname == itemName) {
+			removeItem = true;
+			frontItem = lastItem; /* the one before the current one */
+			itemToRemove = linkedList; /* the item to destroy */
+		}
+
+		lastItem = linkedList;
+		linkedList = linkedList.chain;
+	}
+
+	/* successfully remove the last item */
+	if (removeItem == true) {
+		/* we had an item in front, bridge across the removed item. */
+		if (frontItem) {
+			frontItem.chain = itemToRemove.chain;
+		} else {
+			/* this was the first item. set to chain (can be NULL) */
+			m_itemList = itemToRemove.chain;
+		}
+
+		itemToRemove.Destroy();
+		return (true);
+	}
+#endif
+
+	return (false);
+}
+
+bool
+NSNavAI::AddItem(NSItem theItem)
 {
 	return (false);
 }
diff --git a/src/shared/defs.h b/src/shared/defs.h
index 78a9c213..e70e9a9a 100644
--- a/src/shared/defs.h
+++ b/src/shared/defs.h
@@ -94,13 +94,13 @@ string __fullspawndata;
 #include "NSPhysicsEntity.h"
 #include "NSBrushTrigger.h"
 #include "NSPointTrigger.h"
+#include "NSItem.h"
 #include "NSNavAI.h"
 #include "NSMonster.h"
 #include "NSSquadMonster.h"
 #include "NSTalkMonster.h"
 #include "NSSpawnPoint.h"
 #include "NSProjectile.h"
-#include "NSItem.h"
 #include "NSSpraylogo.h"
 #include "NSPortal.h"
 #include "NSDebris.h"