// These samples exist only at intake. HQ never revisits their entity loadouts.
class ERR_HQVisualContact
{
	IEntity Entity;
	vector Position;
	float ObservedAt;
	bool Escapist;
	string Travel = "unknown";
	string Weapon = "unknown";
}

class ERR_HQObservation
{
	// Require current native line of sight before reading visible equipment.
	static bool IsClearSighting(float age, float traceFraction, float exposure)
	{
		return age >= 0 && age <= 0.5 && traceFraction >= 1 && exposure > 0;
	}

	static bool CanIdentifyWeapon(float distance, float exposure)
	{
		return distance >= 0 && distance <= 150 && exposure >= 0.5;
	}

	static string WeaponCategory(EWeaponType type)
	{
		switch (type)
		{
			case EWeaponType.WT_HANDGUN: return "pistol";
			case EWeaponType.WT_RIFLE: return "rifle";
			case EWeaponType.WT_SNIPERRIFLE: return "sniper rifle";
			case EWeaponType.WT_MACHINEGUN: return "machine gun";
			case EWeaponType.WT_ROCKETLAUNCHER: return "rocket launcher";
			case EWeaponType.WT_GRENADELAUNCHER: return "grenade launcher";
			case EWeaponType.WT_FRAGGRENADE: return "grenade";
			case EWeaponType.WT_SMOKEGRENADE: return "smoke grenade";
		}
		return "unidentified weapon";
	}

	static ERR_HQVisualContact Capture(BaseTarget target, float now)
	{
		if (!target || target.GetTargetCategory() != ETargetCategory.ENEMY || !IsClearSighting(target.GetTimeSinceSeen(), target.GetTraceFraction(), target.GetExposure()))
			return null;
		DamageManagerComponent damage = target.GetDamageManagerComponent();
		if (damage && damage.IsDestroyed())
			return null;
		IEntity entity = target.GetTargetEntity();
		if (!entity)
			return null;
		ERR_HQVisualContact seen = new ERR_HQVisualContact();
		seen.Entity = entity;
		seen.Position = target.GetLastSeenPosition();
		seen.ObservedAt = now - target.GetTimeSinceSeen() * 1000;
		SCR_ChimeraCharacter character = SCR_ChimeraCharacter.Cast(entity);
		if (character)
		{
			if (GetGame().GetPlayerManager())
				seen.Escapist = GetGame().GetPlayerManager().GetPlayerIdFromControlledEntity(entity) > 0;
			seen.Travel = "on foot";
			if (CompartmentAccessComponent.GetVehicleIn(entity))
				seen.Travel = "in vehicle";
			// Read only the drawn weapon; never enumerate weapons or inventory.
			if (CanIdentifyWeapon(target.GetDistance(), target.GetExposure()))
			{
				CharacterControllerComponent controller = CharacterControllerComponent.Cast(entity.FindComponent(CharacterControllerComponent));
				if (controller)
				{
					IEntity heldItem = controller.GetCurrentItemInHands();
					BaseWeaponComponent weapon;
					if (heldItem)
						weapon = BaseWeaponComponent.Cast(heldItem.FindComponent(BaseWeaponComponent));
					seen.Weapon = "none drawn";
					if (weapon)
						seen.Weapon = WeaponCategory(weapon.GetWeaponType());
				}
			}
		}
		else if (Vehicle.Cast(entity))
		{
			seen.Travel = "vehicle";
			if (target.GetUnitType() == EAIUnitType.UnitType_Aircraft)
				seen.Travel = "aircraft";
		}
		return seen;
	}

	static void Gather(SCR_AIGroupUtilityComponent utility, float now, out array<ref ERR_HQVisualContact> samples)
	{
		samples.Clear();
		if (!utility)
			return;
		array<BaseTarget> visible = {};
		utility.ERR_HQGetVisualTargets(visible);
		foreach (BaseTarget target : visible)
		{
			ERR_HQVisualContact seen = Capture(target, now);
			if (!seen)
				continue;
			ERR_HQVisualContact existing;
			foreach (ERR_HQVisualContact sample : samples)
			{
				if (sample.Entity == seen.Entity)
				{
					existing = sample;
					break;
				}
			}
			if (!existing)
			{
				if (samples.Count() < 64)
					samples.Insert(seen);
			}
			else if (seen.ObservedAt > existing.ObservedAt || (seen.ObservedAt == existing.ObservedAt && existing.Weapon == "unknown" && seen.Weapon != "unknown"))
			{
				existing.Position = seen.Position;
				existing.ObservedAt = seen.ObservedAt;
				existing.Travel = seen.Travel;
				existing.Weapon = seen.Weapon;
			}
		}
	}

	static void Describe(ERR_HQReport report, array<ref ERR_HQVisualContact> samples, float now)
	{
		// New observations must not silently inherit old equipment/travel details.
		report.SeenEscapists = -1;
		report.TravelMode = "unknown";
		report.SeenWeapons = "unknown";
		report.DetailsObservedAt = -1;
		if (report.Distress)
			return;
		ERR_HQVisualContact anchor;
		foreach (ERR_HQVisualContact sample : samples)
		{
			if (sample.Entity == report.Target && now - sample.ObservedAt >= 0 && now - sample.ObservedAt <= 500)
			{
				anchor = sample;
				break;
			}
		}
		if (!anchor)
			return;
		report.DetailsObservedAt = anchor.ObservedAt;
		report.TravelMode = anchor.Travel;
		report.SeenWeapons = anchor.Weapon;
		array<IEntity> counted = {};
		array<string> weapons = {};
		string travel;
		foreach (ERR_HQVisualContact sighting : samples)
		{
			if (!sighting.Escapist || !sighting.Entity || counted.Contains(sighting.Entity) || now - sighting.ObservedAt < 0 || now - sighting.ObservedAt > 500 || vector.DistanceXZ(anchor.Position, sighting.Position) > 100)
				continue;
			counted.Insert(sighting.Entity);
			if (travel.IsEmpty())
				travel = sighting.Travel;
			else if (travel != sighting.Travel)
				travel = "mixed travel";
			if (sighting.Weapon != "unknown" && !weapons.Contains(sighting.Weapon) && weapons.Count() < 4)
				weapons.Insert(sighting.Weapon);
		}
		if (counted.IsEmpty())
			return; // A visible vehicle does not reveal its hidden occupants.
		report.SeenEscapists = counted.Count();
		// A vehicle anchor remains a vehicle report, even with people near it.
		if (anchor.Escapist)
			report.TravelMode = travel;
		report.SeenWeapons = "unknown";
		if (!weapons.IsEmpty())
		{
			report.SeenWeapons = weapons[0];
			for (int i = 1; i < weapons.Count(); i++)
				report.SeenWeapons += ", " + weapons[i];
		}
	}
}

modded class SCR_AIGroupUtilityComponent
{
	void ERR_HQGetVisualTargets(out array<BaseTarget> targets)
	{
		targets.Clear();
		foreach (SCR_AIInfoComponent info : m_aInfoComponents)
		{
			if (!info || !info.m_Perception)
				continue;
			AIAgent observer = AIAgent.Cast(info.GetOwner());
			if (!observer || !ERR_Actors.CanFight(observer.GetControlledEntity()))
				continue;
			array<BaseTarget> own = {};
			info.m_Perception.GetTargetsList(own, ETargetCategory.ENEMY);
			foreach (BaseTarget target : own)
			{
				if (target && ERR_HQObservation.IsClearSighting(target.GetTimeSinceSeen(), target.GetTraceFraction(), target.GetExposure()))
					targets.Insert(target);
			}
		}
	}
}