AI: use server relationships to classify NPC friendliness

- Read the server NPC's m_Relationship CUtlVector (entity row for the local
  player first, then the CLASS_PLAYER row): D_LI friendly, D_NU neutral,
  D_HT/D_FR hostile.
- Use it for ESP colours and aimbot/silent-aim/melee target filtering, with
  the existing model heuristic as a fallback.
- Treat bugbait-controlled antlions as friendly when their server
  m_hFollowTarget is set.
- Resolve m_Relationship/m_hFollowTarget datamap offsets and log them.

1 files changed, 60 insertions, 4 deletions

diff --git a/src/server.cpp b/src/server.cpp
index 5599227..4702c44 100644
--- a/src/server.cpp
+++ b/src/server.cpp
@@ -25,7 +25,12 @@ enum { EDICT_UNKNOWN_OFF = 0x0C };
 
 // typedescription_t (32-bit): fieldType@0, fieldName@4, fieldOffset[0]@8,
 // fieldOffset[1]@0xC, fieldSize@0x10, flags@0x12, externalName@0x14
-enum { FIELD_INTEGER = 5, FIELD_CHARACTER = 8 };
+enum {
+  FIELD_INTEGER = 5,
+  FIELD_CHARACTER = 8,
+  FIELD_EMBEDDED = 10,
+  FIELD_EHANDLE = 13
+};
 
 int g_srv_health = -1;
 int g_srv_maxhealth = -1;
@@ -34,6 +39,8 @@ int g_srv_modelindex = -1;
 int g_srv_absvelocity = -1;
 int g_srv_velocity = -1;
 int g_srv_activeweapon = -1;
+static int g_srv_relationship = -1;
+static int g_srv_followtarget = -1;
 static bool g_srv_ready = false;
 static bool g_srv_checked = false;
 
@@ -110,14 +117,17 @@ bool resolve_server_netvars() {
   g_srv_modelindex = datamap_offset("m_nModelIndex", 7); // FIELD_SHORT
   g_srv_absvelocity = datamap_offset("m_vecAbsVelocity", 3); // FIELD_VECTOR
   g_srv_velocity = datamap_offset("m_vecVelocity", 3);       // FIELD_VECTOR
-  g_srv_activeweapon = datamap_offset("m_hActiveWeapon", 13); // FIELD_EHANDLE
+  g_srv_activeweapon = datamap_offset("m_hActiveWeapon", FIELD_EHANDLE);
+  g_srv_relationship = datamap_offset("m_Relationship", FIELD_EMBEDDED);
+  g_srv_followtarget = datamap_offset("m_hFollowTarget", FIELD_EHANDLE);
   g_srv_ready = g_srv_health > 0;
   if (g_srv_ready) {
     logf("server datamap (%s): health=%d maxhealth=%d lifeste=%d "
-         "modelindex=%d absvel=%d vel=%d activeweapon=%d",
+         "modelindex=%d absvel=%d vel=%d activeweapon=%d relationship=%d "
+         "followtarget=%d",
          g_server.path.c_str(), g_srv_health, g_srv_maxhealth, g_srv_lifestate,
          g_srv_modelindex, g_srv_absvelocity, g_srv_velocity,
-         g_srv_activeweapon);
+         g_srv_activeweapon, g_srv_relationship, g_srv_followtarget);
     fail_logged = false;
   } else if (!fail_logged) {
     fail_logged = true;
@@ -189,6 +199,52 @@ int server_model_index(void *base) {
 // networked m_vecVelocity directly is deliberately avoided because the server
 // datamap scan can find a same-named field on another class first. The movement
 // code syncs m_vecVelocity through SetAbsVelocity after the command.
+// Server-side AI relationship (D_ER=0, D_HT=1, D_FR=2, D_LI=3, D_NU=4).
+// m_Relationship is a CUtlVector<Relationship_t>; each entry is
+// EHANDLE entity, Class_T classType, Disposition_t disposition, int priority.
+int server_npc_relation(int idx, int local_idx) {
+  if (!g_srv_ready || g_srv_relationship < 0 || local_idx <= 0)
+    return -1;
+  void *base = nullptr;
+  server_entity_health(idx, nullptr, nullptr, &base);
+  if (!base)
+    return -1;
+  uintptr_t rel = (uintptr_t)base + g_srv_relationship;
+  int count = *(int *)(rel + 12);
+  if (count <= 0 || count > 64)
+    return -1;
+  uintptr_t elems = *(uintptr_t *)(rel + 16);
+  if (!elems)
+    elems = *(uintptr_t *)(rel + 0);
+  if (!elems || (elems & 3))
+    return -1;
+  int class_relation = -1;
+  for (int i = 0; i < count; i++) {
+    uintptr_t e = elems + (uintptr_t)i * 16;
+    uint32_t h = *(uint32_t *)(e + 0);
+    int class_type = *(int *)(e + 4);
+    int disposition = *(int *)(e + 8);
+    if (h != 0 && h != 0xFFFFFFFFu) {
+      if ((int)(h & 0x7FF) == local_idx)
+        return disposition;
+    } else if (class_type == 1) { // CLASS_PLAYER
+      class_relation = disposition;
+    }
+  }
+  return class_relation;
+}
+
+bool server_npc_has_follow_target(int idx) {
+  if (!g_srv_ready || g_srv_followtarget < 0)
+    return false;
+  void *base = nullptr;
+  server_entity_health(idx, nullptr, nullptr, &base);
+  if (!base)
+    return false;
+  uint32_t h = *(uint32_t *)((uintptr_t)base + g_srv_followtarget);
+  return h != 0 && h != 0xFFFFFFFFu;
+}
+
 bool server_set_velocity_z(int idx, float vz) {
   if (!g_srv_ready || !g_iface.engineserver || g_srv_absvelocity <= 0)
     return false;