// Optional HQ destination refinement over delivered memory and authored roads.
// No player/target entity reads, forces, props, assignments or independent timer.
class ERR_HQRoadIntercept
{
 static bool Eligible(ERR_HQBelief belief, float now)
 {
  if (!belief || belief.Kind != ERR_HQMemoryKind.SIGHTING || belief.SampleCount < 2 || belief.MessageId <= 0) return false;
  if (!ERR_ForceRules.Finite(now) || !ERR_ForceRules.Finite(belief.LastDeliveredAt) || belief.LastDeliveredAt > now || belief.LastDeliveredAt < belief.ObservedAt) return false;
  if (belief.TravelMode != "on foot" && belief.TravelMode != "in vehicle") return false;
  if (!ERR_HQPursuitRules.Heading(belief.Velocity, belief.HasVelocity)) return false;
  vector velocity = belief.Velocity; velocity[1] = 0;
  if (velocity.Length() < 2) return false;
  return ERR_HQPursuitRules.Role(belief.Confidence, (now - belief.ObservedAt) / 1000, belief.Radius, true, 0) == ERR_HQPursuitRole.INTERCEPT;
 }
 static bool Ahead(vector origin, vector velocity, vector point)
 {
  if (!ERR_ForceRules.FiniteVector(origin) || !ERR_ForceRules.FiniteVector(point) || !ERR_HQPursuitRules.Heading(velocity, true)) return false;
  vector delta = point - origin; delta[1] = 0; velocity[1] = 0;
  float distance = delta.Length();
  return distance >= 40 && distance <= 250 && vector.Dot(delta.Normalized(), velocity.Normalized()) >= 0.8;
 }
 static bool Unreserved(vector point, array<vector> reserved)
 {
  if (!reserved || reserved.Count() > 128) return false;
  foreach (vector other : reserved)
   if (!ERR_ForceRules.FiniteVector(other) || vector.DistanceXZ(point, other) < 80) return false;
  return true;
 }
 static bool Better(float score, vector point, float bestScore, vector best)
 {
  if (score < bestScore) return true;
  if (score > bestScore) return false;
  if (point[0] != best[0]) return point[0] < best[0];
  if (point[2] != best[2]) return point[2] < best[2];
  return point[1] < best[1];
 }
 // Projection stays on one actual road segment, never a chord through bends.
 static bool FromPolyline(array<vector> points, vector origin, vector velocity, vector seed, array<vector> reserved, out vector result, out float score)
 {
  result = vector.Zero; score = 1e20;
  if (!points || points.Count() < 2 || points.Count() > 1024 || !ERR_ForceRules.FiniteVector(seed)) return false;
  foreach (vector point : points) if (!ERR_ForceRules.FiniteVector(point)) return false;
  bool found;
  for (int i = 1; i < points.Count(); i++)
  {
   vector delta = points[i] - points[i - 1]; delta[1] = 0;
   float length = delta.Length();
   if (length < 0.01) continue;
   vector offset = seed - points[i - 1]; offset[1] = 0;
   float fraction = Math.Clamp(vector.Dot(offset, delta) / (length * length), 0, 1);
   vector candidate = vector.Lerp(points[i - 1], points[i], fraction);
   float distance = vector.DistanceXZ(seed, candidate);
   if (distance > 100 || !Ahead(origin, velocity, candidate) || !Unreserved(candidate, reserved)) continue;
   if (!found || Better(distance, candidate, score, result)) { result = candidate; score = distance; found = true; }
  }
  return found;
 }
 static bool Standable(vector position)
 {
  if (!ERR_ForceRules.FiniteVector(position) || ChimeraWorldUtils.TryGetWaterSurfaceSimple(GetGame().GetWorld(), position)) return false;
  array<vector> edges = {"0.4 0 0", "-0.4 0 0", "0 0 0.4", "0 0 -0.4"};
  foreach (vector edge : edges)
  {
   vector sample = ERR_Actors.Ground(position + edge);
   if (!ERR_ForceRules.FiniteVector(sample) || Math.AbsFloat(sample[1] - position[1]) > 0.4) return false;
  }
  TraceBox body = new TraceBox(); body.Start = position + "0 1 0"; body.End = body.Start + "0 0.01 0";
  body.Mins = "-0.35 -0.9 -0.35"; body.Maxs = "0.35 0.9 0.35";
  body.Flags = TraceFlags.WORLD | TraceFlags.ENTS;
  return GetGame().GetWorld().TraceMove(body, null) == 1;
 }
 static bool Select(ERR_HQBelief belief, float now, array<vector> reserved, out vector result)
 {
  result = vector.Zero;
  if (!Replication.IsServer() || !Eligible(belief, now) || !reserved || reserved.Count() > 128) return false;
  vector seed = ERR_HQPursuitRules.Objective(belief.PredictedPosition, belief.Velocity, true, belief.Confidence,
   (now - belief.ObservedAt) / 1000, belief.Radius, ERR_HQPursuitRole.INTERCEPT, 0);
  if (!ERR_ForceRules.FiniteVector(seed)) return false;
  SCR_AIWorld world = SCR_AIWorld.Cast(GetGame().GetAIWorld());
  if (!world || !world.GetRoadNetworkManager()) return false;
  array<BaseRoad> roads = {};
  world.GetRoadNetworkManager().GetRoadsInAABB(seed + "-100 -1000 -100", seed + "100 1000 100", roads);
  if (roads.Count() > 128) return false;
  int segments;
  bool found;
  vector best;
  float bestScore = 1e20;
  foreach (BaseRoad road : roads)
  {
   if (!road || !ERR_ForceRules.Finite(road.GetWidth()) || road.GetWidth() < 4) continue;
   array<vector> points = {}; road.GetPoints(points);
   if (points.Count() < 2 || points.Count() > 1024) continue;
   segments += points.Count() - 1;
   if (segments > 4096) return false;
   vector candidate;
   float score;
   if (!FromPolyline(points, belief.PredictedPosition, belief.Velocity, seed, reserved, candidate, score)) continue;
   if (!found || Better(score, candidate, bestScore, best)) { best = candidate; bestScore = score; found = true; }
  }
  if (!found) return false;
  vector grounded = ERR_Actors.Ground(best);
  // Terrain grounding must not turn an elevated road/bridge into an offroad post below it.
  if (!ERR_ForceRules.FiniteVector(grounded) || Math.AbsFloat(grounded[1] - best[1]) > 2 || !Standable(grounded)) return false;
  result = grounded;
  return true;
 }
}