#include "actors.hpp"

#include <optional>

#include <components/esm3/esmreader.hpp>
#include <components/esm3/esmwriter.hpp>

#include <components/sceneutil/positionattitudetransform.hpp>
#include <components/debug/debuglog.hpp>
#include <components/misc/rng.hpp>
#include <components/misc/mathutil.hpp>
#include <components/settings/settings.hpp>

#include "../mwworld/esmstore.hpp"
#include "../mwworld/class.hpp"
#include "../mwworld/inventorystore.hpp"
#include "../mwworld/actionequip.hpp"
#include "../mwworld/player.hpp"

#include "../mwbase/world.hpp"
#include "../mwbase/environment.hpp"
#include "../mwbase/windowmanager.hpp"
#include "../mwbase/dialoguemanager.hpp"
#include "../mwbase/soundmanager.hpp"
#include "../mwbase/mechanicsmanager.hpp"
#include "../mwbase/statemanager.hpp"
#include "../mwbase/luamanager.hpp"

#include "../mwmechanics/aibreathe.hpp"

#include "../mwrender/vismask.hpp"

#include "spellcasting.hpp"
#include "steering.hpp"
#include "npcstats.hpp"
#include "creaturestats.hpp"
#include "movement.hpp"
#include "character.hpp"
#include "aicombat.hpp"
#include "aicombataction.hpp"
#include "aifollow.hpp"
#include "aipursue.hpp"
#include "aiwander.hpp"
#include "actor.hpp"
#include "summoning.hpp"
#include "actorutil.hpp"

namespace
{

bool isConscious(const MWWorld::Ptr& ptr)
{
    const MWMechanics::CreatureStats& stats = ptr.getClass().getCreatureStats(ptr);
    return !stats.isDead() && !stats.getKnockedDown();
}

bool isCommanded(const MWWorld::Ptr& actor)
{
    const auto& actorClass = actor.getClass();
    const auto& stats = actorClass.getCreatureStats(actor);
    const bool isActorNpc = actorClass.isNpc();
    const auto level = stats.getLevel();
    for (const auto& params : stats.getActiveSpells())
    {
        for (const auto& effect : params.getEffects())
        {
            if (((effect.mEffectId == ESM::MagicEffect::CommandHumanoid && isActorNpc)
                || (effect.mEffectId == ESM::MagicEffect::CommandCreature && !isActorNpc))
                && effect.mMagnitude >= level)
                return true;
        }
    }
    return false;
}

// Check for command effects having ended and remove package if necessary
void adjustCommandedActor (const MWWorld::Ptr& actor)
{
    if (isCommanded(actor))
        return;

    MWMechanics::CreatureStats& stats = actor.getClass().getCreatureStats(actor);

    stats.getAiSequence().erasePackageIf([](auto& entry)
    {
        if (entry->getTypeId() == MWMechanics::AiPackageTypeId::Follow &&
            static_cast<const MWMechanics::AiFollow*>(entry.get())->isCommanded())
        {
            return true;
        }
        return false;
    });
}

void getRestorationPerHourOfSleep (const MWWorld::Ptr& ptr, float& health, float& magicka)
{
    MWMechanics::CreatureStats& stats = ptr.getClass().getCreatureStats (ptr);
    const MWWorld::Store<ESM::GameSetting>& settings = MWBase::Environment::get().getWorld()->getStore().get<ESM::GameSetting>();

    float endurance = stats.getAttribute (ESM::Attribute::Endurance).getModified ();
    health = 0.1f * endurance;

    float fRestMagicMult = settings.find("fRestMagicMult")->mValue.getFloat ();
    magicka = fRestMagicMult * stats.getAttribute(ESM::Attribute::Intelligence).getModified();
}

template<class T>
void forEachFollowingPackage(std::list<MWMechanics::Actor>& actors, const MWWorld::Ptr& actorPtr, const MWWorld::Ptr& player, T&& func)
{
    for (const MWMechanics::Actor& actor : actors)
    {
        const MWWorld::Ptr &iteratedActor = actor.getPtr();
        if (iteratedActor == player || iteratedActor == actorPtr)
            continue;

        const MWMechanics::CreatureStats &stats = iteratedActor.getClass().getCreatureStats(iteratedActor);
        if (stats.isDead())
            continue;

        // An actor counts as following if AiFollow is the current AiPackage,
        // or there are only Combat and Wander packages before the AiFollow package
        for (const auto& package : stats.getAiSequence())
        {
            if (!func(actor, package))
                break;
        }
    }
}

float getStuntedMagickaDuration(const MWWorld::Ptr& actor)
{
    float remainingTime = 0.f;
    for(const auto& params : actor.getClass().getCreatureStats(actor).getActiveSpells())
    {
        for(const auto& effect : params.getEffects())
        {
            if(effect.mEffectId == ESM::MagicEffect::StuntedMagicka)
            {
                if(effect.mDuration == -1.f)
                    return -1.f;
                remainingTime = std::max(remainingTime, effect.mTimeLeft);
            }
        }
    }
    return remainingTime;
}

void soulTrap(const MWWorld::Ptr& creature)
{
    const auto& stats = creature.getClass().getCreatureStats(creature);
    if(!stats.getMagicEffects().get(ESM::MagicEffect::Soultrap).getMagnitude())
        return;
    int creatureSoulValue = creature.get<ESM::Creature>()->mBase->mData.mSoul;
    if (creatureSoulValue == 0)
        return;
    MWBase::World* world = MWBase::Environment::get().getWorld();
    static const float fSoulgemMult = world->getStore().get<ESM::GameSetting>().find("fSoulgemMult")->mValue.getFloat();
    for(const auto& params : stats.getActiveSpells())
    {
        for(const auto& effect : params.getEffects())
        {
            if(effect.mEffectId != ESM::MagicEffect::Soultrap || effect.mMagnitude <= 0.f)
                continue;
            MWWorld::Ptr caster = world->searchPtrViaActorId(params.getCasterActorId());
            if (caster.isEmpty() || !caster.getClass().isActor())
                continue;

            // Use the smallest soulgem that is large enough to hold the soul
            MWWorld::ContainerStore& container = caster.getClass().getContainerStore(caster);
            MWWorld::ContainerStoreIterator gem = container.end();
            float gemCapacity = std::numeric_limits<float>::max();
            std::string soulgemFilter = "misc_soulgem"; // no other way to check for soulgems? :/
            for (MWWorld::ContainerStoreIterator it = container.begin(MWWorld::ContainerStore::Type_Miscellaneous);
                 it != container.end(); ++it)
            {
                const std::string& id = it->getCellRef().getRefId();
                if (id.size() >= soulgemFilter.size()
                        && id.substr(0,soulgemFilter.size()) == soulgemFilter)
                {
                    float thisGemCapacity = it->get<ESM::Miscellaneous>()->mBase->mData.mValue * fSoulgemMult;
                    if (thisGemCapacity >= creatureSoulValue && thisGemCapacity < gemCapacity
                            && it->getCellRef().getSoul().empty())
                    {
                        gem = it;
                        gemCapacity = thisGemCapacity;
                    }
                }
            }

            if (gem == container.end())
                continue;

            // Set the soul on just one of the gems, not the whole stack
            gem->getContainerStore()->unstack(*gem, caster);
            gem->getCellRef().setSoul(creature.getCellRef().getRefId());

            // Restack the gem with other gems with the same soul
            gem->getContainerStore()->restack(*gem);

            if (caster == MWMechanics::getPlayer())
                MWBase::Environment::get().getWindowManager()->messageBox("#{sSoultrapSuccess}");

            const ESM::Static* fx = world->getStore().get<ESM::Static>()
                    .search("VFX_Soul_Trap");
            if (fx)
                world->spawnEffect("meshes\\" + fx->mModel, "", creature.getRefData().getPosition().asVec3());

            MWBase::Environment::get().getSoundManager()->playSound3D(creature.getRefData().getPosition().asVec3(), "conjuration hit", 1.f, 1.f);
            return; //remove to get vanilla behaviour
        }
    }
}

void removeTemporaryEffects(const MWWorld::Ptr& ptr)
{
    ptr.getClass().getCreatureStats(ptr).getActiveSpells().purge([] (const auto& spell)
    {
        return spell.getType() == ESM::ActiveSpells::Type_Consumable || spell.getType() == ESM::ActiveSpells::Type_Temporary;
    }, ptr);
}
}

namespace MWMechanics
{
    static const int GREETING_SHOULD_START = 4; // how many updates should pass before NPC can greet player
    static const int GREETING_SHOULD_END = 20;  // how many updates should pass before NPC stops turning to player
    static const int GREETING_COOLDOWN = 40;    // how many updates should pass before NPC can continue movement
    static const float DECELERATE_DISTANCE = 512.f;

    namespace
    {
        float getTimeToDestination(const AiPackage& package, const osg::Vec3f& position, float speed, float duration, const osg::Vec3f& halfExtents)
        {
            const auto distanceToNextPathPoint = (package.getNextPathPoint(package.getDestination()) - position).length();
            return (distanceToNextPathPoint - package.getNextPathPointTolerance(speed, duration, halfExtents)) / speed;
        }
    }

    void Actors::updateActor (const MWWorld::Ptr& ptr, float duration)
    {
        // magic effects
        adjustMagicEffects (ptr, duration);

        // fatigue restoration
        calculateRestoration(ptr, duration);
    }

    void Actors::updateHeadTracking(const MWWorld::Ptr& actor, const MWWorld::Ptr& targetActor,
                                    MWWorld::Ptr& headTrackTarget, float& sqrHeadTrackDistance,
                                    bool inCombatOrPursue)
    {
        const auto& actorRefData = actor.getRefData();
        if (!actorRefData.getBaseNode())
            return;

        if (targetActor.getClass().getCreatureStats(targetActor).isDead())
            return;

        static const float fMaxHeadTrackDistance = MWBase::Environment::get().getWorld()->getStore().get<ESM::GameSetting>()
                .find("fMaxHeadTrackDistance")->mValue.getFloat();
        static const float fInteriorHeadTrackMult = MWBase::Environment::get().getWorld()->getStore().get<ESM::GameSetting>()
                .find("fInteriorHeadTrackMult")->mValue.getFloat();
        float maxDistance = fMaxHeadTrackDistance;
        const ESM::Cell* currentCell = actor.getCell()->getCell();
        if (!currentCell->isExterior() && !(currentCell->mData.mFlags & ESM::Cell::QuasiEx))
            maxDistance *= fInteriorHeadTrackMult;

        const osg::Vec3f actor1Pos(actorRefData.getPosition().asVec3());
        const osg::Vec3f actor2Pos(targetActor.getRefData().getPosition().asVec3());
        float sqrDist = (actor1Pos - actor2Pos).length2();

        if (sqrDist > std::min(maxDistance * maxDistance, sqrHeadTrackDistance) && !inCombatOrPursue)
            return;

        // stop tracking when target is behind the actor
        osg::Vec3f actorDirection = actorRefData.getBaseNode()->getAttitude() * osg::Vec3f(0,1,0);
        osg::Vec3f targetDirection(actor2Pos - actor1Pos);
        actorDirection.z() = 0;
        targetDirection.z() = 0;
        if ((actorDirection * targetDirection > 0 || inCombatOrPursue)
            && MWBase::Environment::get().getWorld()->getLOS(actor, targetActor) // check LOS and awareness last as it's the most expensive function
            && MWBase::Environment::get().getMechanicsManager()->awarenessCheck(targetActor, actor))
        {
            sqrHeadTrackDistance = sqrDist;
            headTrackTarget = targetActor;
        }
    }

    void Actors::playIdleDialogue(const MWWorld::Ptr& actor)
    {
        if (!actor.getClass().isActor() || actor == getPlayer() || MWBase::Environment::get().getSoundManager()->sayActive(actor))
            return;

        const CreatureStats &stats = actor.getClass().getCreatureStats(actor);
        if (stats.getAiSetting(CreatureStats::AI_Hello).getModified() == 0)
            return;

        const MWMechanics::AiSequence& seq = stats.getAiSequence();
        if (seq.isInCombat() || seq.hasPackage(AiPackageTypeId::Follow) || seq.hasPackage(AiPackageTypeId::Escort))
            return;

        const osg::Vec3f playerPos(getPlayer().getRefData().getPosition().asVec3());
        const osg::Vec3f actorPos(actor.getRefData().getPosition().asVec3());
        MWBase::World* world = MWBase::Environment::get().getWorld();
        if (world->isSwimming(actor) || (playerPos - actorPos).length2() >= 3000 * 3000)
            return;

        // Our implementation is not FPS-dependent unlike Morrowind's so it needs to be recalibrated.
        // We chose to use the chance MW would have when run at 60 FPS with the default value of the GMST.
        const float delta = MWBase::Environment::get().getFrameDuration() * 6.f;
        static const float fVoiceIdleOdds = world->getStore().get<ESM::GameSetting>().find("fVoiceIdleOdds")->mValue.getFloat();
        if (Misc::Rng::rollProbability(world->getPrng()) * 10000.f < fVoiceIdleOdds * delta && world->getLOS(getPlayer(), actor))
            MWBase::Environment::get().getDialogueManager()->say(actor, "idle");
    }

    void Actors::updateMovementSpeed(const MWWorld::Ptr& actor)
    {
        if (mSmoothMovement)
            return;

        const auto& actorClass = actor.getClass();
        const CreatureStats &stats = actorClass.getCreatureStats(actor);
        const MWMechanics::AiSequence& seq = stats.getAiSequence();

        if (!seq.isEmpty() && seq.getActivePackage().useVariableSpeed())
        {
            osg::Vec3f targetPos = seq.getActivePackage().getDestination();
            osg::Vec3f actorPos = actor.getRefData().getPosition().asVec3();
            float distance = (targetPos - actorPos).length();

            if (distance < DECELERATE_DISTANCE)
            {
                float speedCoef = std::max(0.7f, 0.2f + 0.8f * distance / DECELERATE_DISTANCE);
                auto& movement = actorClass.getMovementSettings(actor);
                movement.mPosition[0] *= speedCoef;
                movement.mPosition[1] *= speedCoef;
            }
        }
    }

    void Actors::updateGreetingState(const MWWorld::Ptr& actor, Actor& actorState, bool turnOnly)
    {
        const auto& actorClass = actor.getClass();
        if (!actorClass.isActor() || actor == getPlayer())
            return;

        const CreatureStats& actorStats = actorClass.getCreatureStats(actor);
        const MWMechanics::AiSequence& seq = actorStats.getAiSequence();
        const auto packageId = seq.getTypeId();

        if (seq.isInCombat() ||
            MWBase::Environment::get().getWorld()->isSwimming(actor) ||
            (packageId != AiPackageTypeId::Wander && packageId != AiPackageTypeId::Travel && packageId != AiPackageTypeId::None))
        {
            actorState.setTurningToPlayer(false);
            actorState.setGreetingTimer(0);
            actorState.setGreetingState(Greet_None);
            return;
        }

        MWWorld::Ptr player = getPlayer();
        osg::Vec3f playerPos(player.getRefData().getPosition().asVec3());
        osg::Vec3f actorPos(actor.getRefData().getPosition().asVec3());
        osg::Vec3f dir = playerPos - actorPos;

        if (actorState.isTurningToPlayer())
        {
            // Reduce the turning animation glitch by using a *HUGE* value of
            // epsilon...  TODO: a proper fix might be in either the physics or the
            // animation subsystem
            if (zTurn(actor, actorState.getAngleToPlayer(), osg::DegreesToRadians(5.f)))
            {
                actorState.setTurningToPlayer(false);
                // An original engine launches an endless idle2 when an actor greets player.
                playAnimationGroup(actor, "idle2", 0, std::numeric_limits<int>::max(), false);
            }
        }

        if (turnOnly)
            return;

        // Play a random voice greeting if the player gets too close
        static const int iGreetDistanceMultiplier = MWBase::Environment::get().getWorld()->getStore()
            .get<ESM::GameSetting>().find("iGreetDistanceMultiplier")->mValue.getInteger();

        float helloDistance = static_cast<float>(actorStats.getAiSetting(CreatureStats::AI_Hello).getModified() * iGreetDistanceMultiplier);
        const auto& playerStats = player.getClass().getCreatureStats(player);

        int greetingTimer = actorState.getGreetingTimer();
        GreetingState greetingState = actorState.getGreetingState();
        if (greetingState == Greet_None)
        {
            if ((playerPos - actorPos).length2() <= helloDistance * helloDistance &&
                !playerStats.isDead() && !actorStats.isParalyzed()
                && MWBase::Environment::get().getWorld()->getLOS(player, actor)
                && MWBase::Environment::get().getMechanicsManager()->awarenessCheck(player, actor))
                greetingTimer++;

            if (greetingTimer >= GREETING_SHOULD_START)
            {
                greetingState = Greet_InProgress;
                MWBase::Environment::get().getDialogueManager()->say(actor, "hello");
                greetingTimer = 0;
            }
        }

        if (greetingState == Greet_InProgress)
        {
            greetingTimer++;

            if (!actorStats.getMovementFlag(CreatureStats::Flag_ForceJump) && !actorStats.getMovementFlag(CreatureStats::Flag_ForceSneak)
                && (greetingTimer <= GREETING_SHOULD_END || MWBase::Environment::get().getSoundManager()->sayActive(actor)))
                turnActorToFacePlayer(actor, actorState, dir);

            if (greetingTimer >= GREETING_COOLDOWN)
            {
                greetingState = Greet_Done;
                greetingTimer = 0;
            }
        }

        if (greetingState == Greet_Done)
        {
            float resetDist = 2 * helloDistance;
            if ((playerPos - actorPos).length2() >= resetDist * resetDist)
                greetingState = Greet_None;
        }

        actorState.setGreetingTimer(greetingTimer);
        actorState.setGreetingState(greetingState);
    }

    void Actors::turnActorToFacePlayer(const MWWorld::Ptr& actor, Actor& actorState, const osg::Vec3f& dir)
    {
        auto& movementSettings = actor.getClass().getMovementSettings(actor);
        movementSettings.mPosition[1] = 0;
        movementSettings.mPosition[0] = 0;

        if (!actorState.isTurningToPlayer())
        {
            float from = dir.x();
            float to = dir.y();
            float angle = std::atan2(from, to);
            actorState.setAngleToPlayer(angle);
            float deltaAngle = Misc::normalizeAngle(angle - actor.getRefData().getPosition().rot[2]);
            if (!mSmoothMovement || std::abs(deltaAngle) > osg::DegreesToRadians(60.f))
                actorState.setTurningToPlayer(true);
        }
    }

    void Actors::stopCombat(const MWWorld::Ptr& ptr)
    {
        auto& ai = ptr.getClass().getCreatureStats(ptr).getAiSequence();
        std::vector<MWWorld::Ptr> targets;
        if(ai.getCombatTargets(targets))
        {
            std::set<MWWorld::Ptr> allySet;
            getActorsSidingWith(ptr, allySet);
            allySet.insert(ptr);
            std::vector<MWWorld::Ptr> allies(allySet.begin(), allySet.end());
            for(const auto& ally : allies)
                ally.getClass().getCreatureStats(ally).getAiSequence().stopCombat(targets);
            for(const auto& target : targets)
                target.getClass().getCreatureStats(target).getAiSequence().stopCombat(allies);
        }
    }

    void Actors::engageCombat(const MWWorld::Ptr& actor1, const MWWorld::Ptr& actor2, std::map<const MWWorld::Ptr, const std::set<MWWorld::Ptr> >& cachedAllies, bool againstPlayer)
    {
        // No combat for totally static creatures
        if (!actor1.getClass().isMobile(actor1))
            return;

        CreatureStats& creatureStats1 = actor1.getClass().getCreatureStats(actor1);
        if (creatureStats1.isDead() || creatureStats1.getAiSequence().isInCombat(actor2))
            return;

        const CreatureStats& creatureStats2 = actor2.getClass().getCreatureStats(actor2);
        if (creatureStats2.isDead())
            return;

        const osg::Vec3f actor1Pos(actor1.getRefData().getPosition().asVec3());
        const osg::Vec3f actor2Pos(actor2.getRefData().getPosition().asVec3());
        const float sqrDist = (actor1Pos - actor2Pos).length2();

        if (sqrDist > mActorsProcessingRange * mActorsProcessingRange)
            return;

        // If this is set to true, actor1 will start combat with actor2 if the awareness check at the end of the method returns true
        bool aggressive = false;

        // Get actors allied with actor1. Includes those following or escorting actor1, actors following or escorting those actors, (recursive)
        // and any actor currently being followed or escorted by actor1
        std::set<MWWorld::Ptr> allies1;

        getActorsSidingWith(actor1, allies1, cachedAllies);

        const auto mechanicsManager = MWBase::Environment::get().getMechanicsManager();
        // If an ally of actor1 has been attacked by actor2 or has attacked actor2, start combat between actor1 and actor2
        for (const MWWorld::Ptr& ally : allies1)
        {
            if (creatureStats1.getAiSequence().isInCombat(ally))
                continue;

            if (creatureStats2.matchesActorId(ally.getClass().getCreatureStats(ally).getHitAttemptActorId()))
            {
                mechanicsManager->startCombat(actor1, actor2);
                // Also set the same hit attempt actor. Otherwise, if fighting the player, they may stop combat
                // if the player gets out of reach, while the ally would continue combat with the player
                creatureStats1.setHitAttemptActorId(ally.getClass().getCreatureStats(ally).getHitAttemptActorId());
                return;
            }

            // If there's been no attack attempt yet but an ally of actor1 is in combat with actor2, become aggressive to actor2
            if (ally.getClass().getCreatureStats(ally).getAiSequence().isInCombat(actor2))
                aggressive = true;
        }

        std::set<MWWorld::Ptr> playerAllies;
        getActorsSidingWith(MWMechanics::getPlayer(), playerAllies, cachedAllies);

        bool isPlayerFollowerOrEscorter = playerAllies.find(actor1) != playerAllies.end();

        // If actor2 and at least one actor2 are in combat with actor1, actor1 and its allies start combat with them
        // Doesn't apply for player followers/escorters
        if (!aggressive && !isPlayerFollowerOrEscorter)
        {
            // Check that actor2 is in combat with actor1
            if (creatureStats2.getAiSequence().isInCombat(actor1))
            {
                std::set<MWWorld::Ptr> allies2;

                getActorsSidingWith(actor2, allies2, cachedAllies);

                // Check that an ally of actor2 is also in combat with actor1
                for (const MWWorld::Ptr& ally2 : allies2)
                {
                    if (ally2.getClass().getCreatureStats(ally2).getAiSequence().isInCombat(actor1))
                    {
                        mechanicsManager->startCombat(actor1, actor2);
                        // Also have actor1's allies start combat
                        for (const MWWorld::Ptr& ally1 : allies1)
                            mechanicsManager->startCombat(ally1, actor2);
                        return;
                    }
                }
            }
        }

        // Stop here if target is unreachable
        if (!canFight(actor1, actor2))
            return;

        // If set in the settings file, player followers and escorters will become aggressive toward enemies in combat with them or the player
        static const bool followersAttackOnSight = Settings::Manager::getBool("followers attack on sight", "Game");
        if (!aggressive && isPlayerFollowerOrEscorter && followersAttackOnSight)
        {
            if (creatureStats2.getAiSequence().isInCombat(actor1))
                aggressive = true;
            else
            {
                for (const MWWorld::Ptr& ally : allies1)
                {
                    if (creatureStats2.getAiSequence().isInCombat(ally))
                    {
                        aggressive = true;
                        break;
                    }
                }
            }
        }

        // Do aggression check if actor2 is the player or a player follower or escorter
        if (!aggressive)
        {
            if (againstPlayer || playerAllies.find(actor2) != playerAllies.end())
            {
                // Player followers and escorters with high fight should not initiate combat with the player or with
                // other player followers or escorters
                if (!isPlayerFollowerOrEscorter)
                    aggressive = mechanicsManager->isAggressive(actor1, actor2);
            }
        }

        // Make guards go aggressive with creatures that are in combat, unless the creature is a follower or escorter
        const auto world = MWBase::Environment::get().getWorld();
        if (!aggressive && actor1.getClass().isClass(actor1, "Guard") && !actor2.getClass().isNpc() && creatureStats2.getAiSequence().isInCombat())
        {
            // Check if the creature is too far
            static const float fAlarmRadius = world->getStore().get<ESM::GameSetting>().find("fAlarmRadius")->mValue.getFloat();
            if (sqrDist > fAlarmRadius * fAlarmRadius)
                return;

            bool followerOrEscorter = false;
            for (const auto& package : creatureStats2.getAiSequence())
            {
                // The follow package must be first or have nothing but combat before it
                if (package->sideWithTarget())
                {
                    followerOrEscorter = true;
                    break;
                }
                else if (package->getTypeId() != MWMechanics::AiPackageTypeId::Combat)
                    break;
            }
            if (!followerOrEscorter)
                aggressive = true;
        }

        // If any of the above conditions turned actor1 aggressive towards actor2, do an awareness check. If it passes, start combat with actor2.
        if (aggressive)
        {
            bool LOS = world->getLOS(actor1, actor2) &&
                mechanicsManager->awarenessCheck(actor2, actor1);

            if (LOS)
                mechanicsManager->startCombat(actor1, actor2);
        }
    }

    void Actors::adjustMagicEffects (const MWWorld::Ptr& creature, float duration)
    {
        CreatureStats& creatureStats = creature.getClass().getCreatureStats (creature);
        bool wasDead = creatureStats.isDead();

        creatureStats.getActiveSpells().update(creature, duration);

        if (!wasDead && creatureStats.isDead())
        {
            // The actor was killed by a magic effect. Figure out if the player was responsible for it.
            const ActiveSpells& spells = creatureStats.getActiveSpells();
            MWWorld::Ptr player = getPlayer();
            std::set<MWWorld::Ptr> playerFollowers;
            getActorsSidingWith(player, playerFollowers);

            for (ActiveSpells::TIterator it = spells.begin(); it != spells.end(); ++it)
            {
                bool actorKilled = false;

                const ActiveSpells::ActiveSpellParams& spell = *it;
                MWWorld::Ptr caster = MWBase::Environment::get().getWorld()->searchPtrViaActorId(spell.getCasterActorId());
                for (const auto& effect : spell.getEffects())
                {
                    static const std::array<int, 7> damageEffects{
                        ESM::MagicEffect::FireDamage, ESM::MagicEffect::ShockDamage, ESM::MagicEffect::FrostDamage, ESM::MagicEffect::Poison,
                        ESM::MagicEffect::SunDamage, ESM::MagicEffect::DamageHealth, ESM::MagicEffect::AbsorbHealth
                    };

                    bool isDamageEffect = std::find(damageEffects.begin(), damageEffects.end(), effect.mEffectId) != damageEffects.end();

                    if (isDamageEffect)
                    {
                        if (caster.getClass().isNpc() && caster.getClass().getNpcStats(caster).isWerewolf())
                            caster.getClass().getNpcStats(caster).addWerewolfKill();
                        if (caster == player || playerFollowers.find(caster) != playerFollowers.end())
                        {
                            MWBase::Environment::get().getMechanicsManager()->actorKilled(creature, player);
                            actorKilled = true;
                            break;
                        }
                    }
                }

                if (actorKilled)
                    break;
            }
        }

        // updateSummons assumes the actor belongs to a cell.
        // This assumption isn't always valid for the player character.
        if (!creature.isInCell())
            return;

        if (!creatureStats.getSummonedCreatureMap().empty() || !creatureStats.getSummonedCreatureGraveyard().empty())
            updateSummons(creature, mTimerDisposeSummonsCorpses == 0.f);
    }

    void Actors::restoreDynamicStats (const MWWorld::Ptr& ptr, double hours, bool sleep)
    {
        MWMechanics::CreatureStats& stats = ptr.getClass().getCreatureStats (ptr);
        if (stats.isDead())
            return;

        const MWWorld::Store<ESM::GameSetting>& settings = MWBase::Environment::get().getWorld()->getStore().get<ESM::GameSetting>();

        if (sleep)
        {
            float health, magicka;
            getRestorationPerHourOfSleep(ptr, health, magicka);

            DynamicStat<float> stat = stats.getHealth();
            stat.setCurrent(stat.getCurrent() + health * hours);
            stats.setHealth(stat);

            double restoreHours = hours;
            bool stunted = stats.getMagicEffects ().get(ESM::MagicEffect::StuntedMagicka).getMagnitude() > 0;
            if (stunted)
            {
                // Stunted Magicka effect should be taken into account.
                float remainingTime = getStuntedMagickaDuration(ptr);

                // Take a maximum remaining duration of Stunted Magicka effects (-1 is a constant one) in game hours.
                if (remainingTime > 0)
                {
                    double timeScale = MWBase::Environment::get().getWorld()->getTimeScaleFactor();
                    if(timeScale == 0.0)
                        timeScale = 1;

                    restoreHours = std::max(0.0, hours - remainingTime * timeScale / 3600.f);
                }
                else if (remainingTime == -1)
                    restoreHours = 0;
            }

            if (restoreHours > 0)
            {
                stat = stats.getMagicka();
                stat.setCurrent(stat.getCurrent() + magicka * restoreHours);
                stats.setMagicka(stat);
            }
        }

        // Current fatigue can be above base value due to a fortify effect.
        // In that case stop here and don't try to restore.
        DynamicStat<float> fatigue = stats.getFatigue();
        if (fatigue.getCurrent() >= fatigue.getBase())
            return;

        // Restore fatigue
        float fFatigueReturnBase = settings.find("fFatigueReturnBase")->mValue.getFloat ();
        float fFatigueReturnMult = settings.find("fFatigueReturnMult")->mValue.getFloat ();
        float fEndFatigueMult = settings.find("fEndFatigueMult")->mValue.getFloat ();

        float endurance = stats.getAttribute (ESM::Attribute::Endurance).getModified ();

        float normalizedEncumbrance = ptr.getClass().getNormalizedEncumbrance(ptr);
        if (normalizedEncumbrance > 1)
            normalizedEncumbrance = 1;

        float x = fFatigueReturnBase + fFatigueReturnMult * (1 - normalizedEncumbrance);
        x *= fEndFatigueMult * endurance;

        fatigue.setCurrent (fatigue.getCurrent() + 3600 * x * hours);
        stats.setFatigue (fatigue);
    }

    void Actors::calculateRestoration (const MWWorld::Ptr& ptr, float duration)
    {
        if (ptr.getClass().getCreatureStats(ptr).isDead())
            return;

        MWMechanics::CreatureStats& stats = ptr.getClass().getCreatureStats (ptr);

        // Current fatigue can be above base value due to a fortify effect.
        // In that case stop here and don't try to restore.
        DynamicStat<float> fatigue = stats.getFatigue();
        if (fatigue.getCurrent() >= fatigue.getBase())
            return;

        // Restore fatigue
        float endurance = stats.getAttribute(ESM::Attribute::Endurance).getModified();
        const MWWorld::Store<ESM::GameSetting>& settings = MWBase::Environment::get().getWorld()->getStore().get<ESM::GameSetting>();
        static const float fFatigueReturnBase = settings.find("fFatigueReturnBase")->mValue.getFloat ();
        static const float fFatigueReturnMult = settings.find("fFatigueReturnMult")->mValue.getFloat ();

        float x = fFatigueReturnBase + fFatigueReturnMult * endurance;

        fatigue.setCurrent (fatigue.getCurrent() + duration * x);
        stats.setFatigue (fatigue);
    }

    bool Actors::isAttackPreparing(const MWWorld::Ptr& ptr)
    {
        const auto it = mIndex.find(ptr.mRef);
        if (it == mIndex.end())
            return false;
        return it->second->getCharacterController().isAttackPreparing();
    }

    bool Actors::isRunning(const MWWorld::Ptr& ptr)
    {
        const auto it = mIndex.find(ptr.mRef);
        if (it == mIndex.end())
            return false;
        return it->second->getCharacterController().isRunning();
    }

    bool Actors::isSneaking(const MWWorld::Ptr& ptr)
    {
        const auto it = mIndex.find(ptr.mRef);
        if (it == mIndex.end())
            return false;
        return it->second->getCharacterController().isSneaking();
    }

    void Actors::updateDrowning(const MWWorld::Ptr& ptr, float duration, bool isKnockedOut, bool isPlayer)
    {
        auto& actorClass = ptr.getClass();
        NpcStats& stats = actorClass.getNpcStats(ptr);

        // When npc stats are just initialized, mTimeToStartDrowning == -1 and we should get value from GMST
        static const float fHoldBreathTime = MWBase::Environment::get().getWorld()->getStore().get<ESM::GameSetting>().find("fHoldBreathTime")->mValue.getFloat();
        if (stats.getTimeToStartDrowning() == -1.f)
            stats.setTimeToStartDrowning(fHoldBreathTime);

        if (!isPlayer && stats.getTimeToStartDrowning() < fHoldBreathTime / 2)
        {
            AiSequence& seq = actorClass.getCreatureStats(ptr).getAiSequence();
            if (seq.getTypeId() != AiPackageTypeId::Breathe) //Only add it once
                seq.stack(AiBreathe(), ptr);
        }

        MWBase::World* world = MWBase::Environment::get().getWorld();
        bool knockedOutUnderwater = (isKnockedOut && world->isUnderwater(ptr.getCell(), osg::Vec3f(ptr.getRefData().getPosition().asVec3())));
        if ((world->isSubmerged(ptr) || knockedOutUnderwater)
            && stats.getMagicEffects().get(ESM::MagicEffect::WaterBreathing).getMagnitude() == 0)
        {
            float timeLeft = 0.0f;
            if (knockedOutUnderwater)
                stats.setTimeToStartDrowning(0);
            else
            {
                timeLeft = stats.getTimeToStartDrowning() - duration;
                if (timeLeft < 0.0f)
                    timeLeft = 0.0f;
                stats.setTimeToStartDrowning(timeLeft);
            }

            bool godmode = isPlayer && world->getGodModeState();

            if (timeLeft == 0.0f && !godmode)
            {
                // If drowning, apply 3 points of damage per second
                static const float fSuffocationDamage = world->getStore().get<ESM::GameSetting>().find("fSuffocationDamage")->mValue.getFloat();
                DynamicStat<float> health = stats.getHealth();
                health.setCurrent(health.getCurrent() - fSuffocationDamage * duration);
                stats.setHealth(health);

                // Play a drowning sound
                MWBase::SoundManager* sndmgr = MWBase::Environment::get().getSoundManager();
                if (!sndmgr->getSoundPlaying(ptr, "drown"))
                    sndmgr->playSound3D(ptr, "drown", 1.0f, 1.0f);

                if (isPlayer)
                    MWBase::Environment::get().getWindowManager()->activateHitOverlay(false);
            }
        }
        else
            stats.setTimeToStartDrowning(fHoldBreathTime);
    }

    void Actors::updateEquippedLight(const MWWorld::Ptr& ptr, float duration, bool mayEquip)
    {
        const bool isPlayer = (ptr == getPlayer());

        auto& actorClass = ptr.getClass();
        auto& inventoryStore = actorClass.getInventoryStore(ptr);

        auto heldIter = inventoryStore.getSlot(MWWorld::InventoryStore::Slot_CarriedLeft);

        /**
         * Automatically equip NPCs torches at night and unequip them at day
         */
        if (!isPlayer)
        {
            auto torchIter = std::find_if(std::begin(inventoryStore), std::end(inventoryStore), [&](auto entry)
                {
                    return entry.getType() == ESM::Light::sRecordId &&
                        entry.getClass().canBeEquipped(entry, ptr).first;
                });
            if (mayEquip)
            {
                if (torchIter != inventoryStore.end())
                {
                    if (!actorClass.getCreatureStats(ptr).getAiSequence().isInCombat())
                    {
                        // For non-hostile NPCs, unequip whatever is in the left slot in favor of a light.
                        if (heldIter != inventoryStore.end() && heldIter->getType() != ESM::Light::sRecordId)
                            inventoryStore.unequipItem(*heldIter, ptr);
                    }
                    else if (heldIter == inventoryStore.end() || heldIter->getType() == ESM::Light::sRecordId)
                    {
                        // For hostile NPCs, see if they have anything better to equip first
                        auto shield = inventoryStore.getPreferredShield(ptr);
                        if (shield != inventoryStore.end())
                            inventoryStore.equip(MWWorld::InventoryStore::Slot_CarriedLeft, shield, ptr);
                    }

                    heldIter = inventoryStore.getSlot(MWWorld::InventoryStore::Slot_CarriedLeft);

                    // If we have a torch and can equip it, then equip it now.
                    if (heldIter == inventoryStore.end())
                    {
                        inventoryStore.equip(MWWorld::InventoryStore::Slot_CarriedLeft, torchIter, ptr);
                    }
                }
            }
            else
            {
                if (heldIter != inventoryStore.end() && heldIter->getType() == ESM::Light::sRecordId)
                {
                    // At day, unequip lights and auto equip shields or other suitable items
                    // (Note: autoEquip will ignore lights)
                    inventoryStore.autoEquip(ptr);
                }
            }
        }

        heldIter = inventoryStore.getSlot(MWWorld::InventoryStore::Slot_CarriedLeft);

        //If holding a light...
        if(heldIter.getType() == MWWorld::ContainerStore::Type_Light)
        {
            const auto world = MWBase::Environment::get().getWorld();
            // Use time from the player's light
            if(isPlayer)
            {
                // But avoid using it up if the light source is hidden
                MWRender::Animation *anim = world->getAnimation(ptr);
                if (anim && anim->getCarriedLeftShown())
                {
                    float timeRemaining = heldIter->getClass().getRemainingUsageTime(*heldIter);

                    // -1 is infinite light source. Other negative values are treated as 0.
                    if (timeRemaining != -1.0f)
                    {
                        timeRemaining -= duration;
                        if (timeRemaining <= 0.f)
                        {
                            inventoryStore.remove(*heldIter, 1, ptr); // remove it
                            return;
                        }

                        heldIter->getClass().setRemainingUsageTime(*heldIter, timeRemaining);
                    }
                }
            }

            // Both NPC and player lights extinguish in water.
            if(world->isSwimming(ptr))
            {
                inventoryStore.remove(*heldIter, 1, ptr); // remove it

                // ...But, only the player makes a sound.
                if(isPlayer)
                    MWBase::Environment::get().getSoundManager()->playSound("torch out",
                            1.0, 1.0, MWSound::Type::Sfx, MWSound::PlayMode::NoEnv);
            }
        }
    }

    void Actors::updateCrimePursuit(const MWWorld::Ptr& ptr, float duration)
    {
        MWWorld::Ptr player = getPlayer();
        if (ptr == player)
            return;

        auto& actorClass = ptr.getClass();
        if (!actorClass.isNpc())
            return;

        // get stats of witness
        CreatureStats& creatureStats = ptr.getClass().getCreatureStats(ptr);
        NpcStats& npcStats = ptr.getClass().getNpcStats(ptr);

        const auto& playerClass = player.getClass();
        const auto& playerStats = playerClass.getNpcStats(player);
        if (playerStats.isWerewolf())
            return;

        const auto mechanicsManager = MWBase::Environment::get().getMechanicsManager();
        const auto world = MWBase::Environment::get().getWorld();

        if (actorClass.isClass(ptr, "Guard") && creatureStats.getAiSequence().isInPursuit() && !creatureStats.getAiSequence().isInCombat()
            && creatureStats.getMagicEffects().get(ESM::MagicEffect::CalmHumanoid).getMagnitude() == 0)
        {
            const MWWorld::ESMStore& esmStore = world->getStore();
            static const int cutoff = esmStore.get<ESM::GameSetting>().find("iCrimeThreshold")->mValue.getInteger();
            // Force dialogue on sight if bounty is greater than the cutoff
            // In vanilla morrowind, the greeting dialogue is scripted to either arrest the player (< 5000 bounty) or attack (>= 5000 bounty)
            if (playerStats.getBounty() >= cutoff
                // TODO: do not run these two every frame. keep an Aware state for each actor and update it every 0.2 s or so?
                && world->getLOS(ptr, player)
                && mechanicsManager->awarenessCheck(player, ptr))
            {
                static const int iCrimeThresholdMultiplier = esmStore.get<ESM::GameSetting>().find("iCrimeThresholdMultiplier")->mValue.getInteger();
                if (playerStats.getBounty() >= cutoff * iCrimeThresholdMultiplier)
                {
                    mechanicsManager->startCombat(ptr, player);
                    creatureStats.setHitAttemptActorId(playerClass.getCreatureStats(player).getActorId()); // Stops the guard from quitting combat if player is unreachable
                }
                else
                    creatureStats.getAiSequence().stack(AiPursue(player), ptr);
                creatureStats.setAlarmed(true);
                npcStats.setCrimeId(world->getPlayer().getNewCrimeId());
            }
        }

        // if I was a witness to a crime
        if (npcStats.getCrimeId() != -1)
        {
            // if you've paid for your crimes and I havent noticed
            if (npcStats.getCrimeId() <= world->getPlayer().getCrimeId())
            {
                // Calm witness down
                if (ptr.getClass().isClass(ptr, "Guard"))
                    creatureStats.getAiSequence().stopPursuit();
                stopCombat(ptr);

                // Reset factors to attack
                creatureStats.setAttacked(false);
                creatureStats.setAlarmed(false);
                creatureStats.setAiSetting(CreatureStats::AI_Fight, ptr.getClass().getBaseFightRating(ptr));

                // Update witness crime id
                npcStats.setCrimeId(-1);
            }
        }
    }

    Actors::Actors() : mSmoothMovement(Settings::Manager::getBool("smooth movement", "Game"))
    {
        mTimerDisposeSummonsCorpses = 0.2f; // We should add a delay between summoned creature death and its corpse despawning

        updateProcessingRange();
    }

    float Actors::getProcessingRange() const
    {
        return mActorsProcessingRange;
    }

    void Actors::updateProcessingRange()
    {
        // We have to cap it since using high values (larger than 7168) will make some quests harder or impossible to complete (bug #1876)
        static const float maxRange = 7168.f;
        static const float minRange = maxRange / 2.f;

        mActorsProcessingRange = std::clamp(Settings::Manager::getFloat("actors processing range", "Game"), minRange, maxRange);
    }

    void Actors::addActor (const MWWorld::Ptr& ptr, bool updateImmediately)
    {
        removeActor(ptr, true);

        MWRender::Animation *anim = MWBase::Environment::get().getWorld()->getAnimation(ptr);
        if (!anim)
            return;
        const auto it = mActors.emplace(mActors.end(), ptr, anim);
        mIndex.emplace(ptr.mRef, it);

        if (updateImmediately)
            it->getCharacterController().update(0);

        // We should initially hide actors outside of processing range.
        // Note: since we update player after other actors, distance will be incorrect during teleportation.
        // Do not update visibility if player was teleported, so actors will be visible during teleportation frame.
        if (MWBase::Environment::get().getWorld()->getPlayer().wasTeleported())
            return;

        updateVisibility(ptr, it->getCharacterController());
    }

    void Actors::updateVisibility (const MWWorld::Ptr& ptr, CharacterController& ctrl)
    {
        MWWorld::Ptr player = MWMechanics::getPlayer();
        if (ptr == player)
            return;

        const float dist = (player.getRefData().getPosition().asVec3() - ptr.getRefData().getPosition().asVec3()).length();
        if (dist > mActorsProcessingRange)
        {
            ptr.getRefData().getBaseNode()->setNodeMask(0);
            return;
        }
        else
            ptr.getRefData().getBaseNode()->setNodeMask(MWRender::Mask_Actor);

        // Fade away actors on large distance (>90% of actor's processing distance)
        float visibilityRatio = 1.0;
        float fadeStartDistance = mActorsProcessingRange*0.9f;
        float fadeEndDistance = mActorsProcessingRange;
        float fadeRatio = (dist - fadeStartDistance)/(fadeEndDistance - fadeStartDistance);
        if (fadeRatio > 0)
            visibilityRatio -= std::max(0.f, fadeRatio);

        visibilityRatio = std::min(1.f, visibilityRatio);

        ctrl.setVisibility(visibilityRatio);
    }

    void Actors::removeActor (const MWWorld::Ptr& ptr, bool keepActive)
    {
        const auto iter = mIndex.find(ptr.mRef);
        if (iter != mIndex.end())
        {
            if(!keepActive)
                removeTemporaryEffects(iter->second->getPtr());
            mActors.erase(iter->second);
            mIndex.erase(iter);
        }
    }

    void Actors::castSpell(const MWWorld::Ptr& ptr, const std::string& spellId, bool manualSpell)
    {
        const auto iter = mIndex.find(ptr.mRef);
        if (iter != mIndex.end())
            iter->second->getCharacterController().castSpell(spellId, manualSpell);
    }

    bool Actors::isActorDetected(const MWWorld::Ptr& actor, const MWWorld::Ptr& observer)
    {
        if (!actor.getClass().isActor())
            return false;

        // If an observer is NPC, check if he detected an actor
        if (!observer.isEmpty() && observer.getClass().isNpc())
        {
            return
                MWBase::Environment::get().getWorld()->getLOS(observer, actor) &&
                MWBase::Environment::get().getMechanicsManager()->awarenessCheck(actor, observer);
        }

        // Otherwise check if any actor in AI processing range sees the target actor
        std::vector<MWWorld::Ptr> neighbors;
        osg::Vec3f position (actor.getRefData().getPosition().asVec3());
        getObjectsInRange(position, mActorsProcessingRange, neighbors);
        for (const MWWorld::Ptr &neighbor : neighbors)
        {
            if (neighbor == actor)
                continue;

            bool result = MWBase::Environment::get().getWorld()->getLOS(neighbor, actor)
                       && MWBase::Environment::get().getMechanicsManager()->awarenessCheck(actor, neighbor);

            if (result)
                return true;
        }

        return false;
    }

    void Actors::updateActor(const MWWorld::Ptr &old, const MWWorld::Ptr &ptr)
    {
        const auto iter = mIndex.find(old.mRef);
        if (iter != mIndex.end())
            iter->second->updatePtr(ptr);
    }

    void Actors::dropActors (const MWWorld::CellStore *cellStore, const MWWorld::Ptr& ignore)
    {
        for (auto iter = mActors.begin(); iter != mActors.end();)
        {
            if ((iter->getPtr().isInCell() && iter->getPtr().getCell() == cellStore) && iter->getPtr() != ignore)
            {
                removeTemporaryEffects(iter->getPtr());
                mIndex.erase(iter->getPtr().mRef);
                iter = mActors.erase(iter);
            }
            else
                ++iter;
        }
    }

    void Actors::updateCombatMusic ()
    {
        MWWorld::Ptr player = getPlayer();
        const osg::Vec3f playerPos = player.getRefData().getPosition().asVec3();
        bool hasHostiles = false; // need to know this to play Battle music
        bool aiActive = MWBase::Environment::get().getMechanicsManager()->isAIActive();

        if (aiActive)
        {
            for (const Actor& actor : mActors)
            {
                if (actor.getPtr() == player) continue;

                bool inProcessingRange = (playerPos - actor.getPtr().getRefData().getPosition().asVec3()).length2() <= mActorsProcessingRange*mActorsProcessingRange;
                if (inProcessingRange)
                {
                    MWMechanics::CreatureStats& stats = actor.getPtr().getClass().getCreatureStats(actor.getPtr());
                    if (!stats.isDead() && stats.getAiSequence().isInCombat())
                    {
                        hasHostiles = true;
                        break;
                    }
                }
            }
        }

        // check if we still have any player enemies to switch music
        if (mCurrentMusic != MusicType::Explore && !hasHostiles
                && !(player.getClass().getCreatureStats(player).isDead()
                     && MWBase::Environment::get().getSoundManager()->isMusicPlaying()))
        {
            MWBase::Environment::get().getSoundManager()->playPlaylist(std::string("Explore"));
            mCurrentMusic = MusicType::Explore;
        }
        else if (mCurrentMusic != MusicType::Battle && hasHostiles)
        {
            MWBase::Environment::get().getSoundManager()->playPlaylist(std::string("Battle"));
            mCurrentMusic = MusicType::Battle;
        }

    }

    void Actors::predictAndAvoidCollisions(float duration)
    {
        if (!MWBase::Environment::get().getMechanicsManager()->isAIActive())
            return;

        const float minGap = 10.f;
        const float maxDistForPartialAvoiding = 200.f;
        const float maxDistForStrictAvoiding = 100.f;
        const float maxTimeToCheck = 2.0f;
        static const bool giveWayWhenIdle = Settings::Manager::getBool("NPCs give way", "Game");

        const MWWorld::Ptr player = getPlayer();
        const MWBase::World* world = MWBase::Environment::get().getWorld();
        for (const Actor& actor : mActors)
        {
            const MWWorld::Ptr& ptr = actor.getPtr();
            if (ptr == player)
                continue; // Don't interfere with player controls.

            float maxSpeed = ptr.getClass().getMaxSpeed(ptr);
            if (maxSpeed == 0.0)
                continue; // Can't move, so there is no sense to predict collisions.

            Movement& movement = ptr.getClass().getMovementSettings(ptr);
            osg::Vec2f origMovement(movement.mPosition[0], movement.mPosition[1]);
            bool isMoving = origMovement.length2() > 0.01;
            if (movement.mPosition[1] < 0)
                continue; // Actors can not see others when move backward.

            // Moving NPCs always should avoid collisions.
            // Standing NPCs give way to moving ones if they are not in combat (or pursue) mode and either
            // follow player or have a AIWander package with non-empty wander area.
            bool shouldAvoidCollision = isMoving;
            bool shouldGiveWay = false;
            bool shouldTurnToApproachingActor = !isMoving;
            MWWorld::Ptr currentTarget; // Combat or pursue target (NPCs should not avoid collision with their targets).
            const auto& aiSequence = ptr.getClass().getCreatureStats(ptr).getAiSequence();
            if (!aiSequence.isEmpty())
            {
                const auto& package = aiSequence.getActivePackage();
                if (package.getTypeId() == AiPackageTypeId::Follow)
                {
                    shouldAvoidCollision = true;
                }
                else if (package.getTypeId() == AiPackageTypeId::Wander && giveWayWhenIdle)
                {
                    if (!static_cast<const AiWander&>(package).isStationary())
                        shouldGiveWay = true;
                }
                else if (package.getTypeId() == AiPackageTypeId::Combat || package.getTypeId() == AiPackageTypeId::Pursue)
                {
                    currentTarget = package.getTarget();
                    shouldAvoidCollision = isMoving;
                    shouldTurnToApproachingActor = false;
                }
            }

            if (!shouldAvoidCollision && !shouldGiveWay)
                continue;

            osg::Vec2f baseSpeed = origMovement * maxSpeed;
            osg::Vec3f basePos = ptr.getRefData().getPosition().asVec3();
            float baseRotZ = ptr.getRefData().getPosition().rot[2];
            const osg::Vec3f halfExtents = world->getHalfExtents(ptr);
            float maxDistToCheck = isMoving ? maxDistForPartialAvoiding : maxDistForStrictAvoiding;

            float timeToCheck = maxTimeToCheck;
            if (!shouldGiveWay && !aiSequence.isEmpty())
                timeToCheck = std::min(timeToCheck, getTimeToDestination(**aiSequence.begin(), basePos, maxSpeed, duration, halfExtents));

            float timeToCollision = timeToCheck;
            osg::Vec2f movementCorrection(0, 0);
            float angleToApproachingActor = 0;

            // Iterate through all other actors and predict collisions.
            for (const Actor& otherActor : mActors)
            {
                const MWWorld::Ptr& otherPtr = otherActor.getPtr();
                if (otherPtr == ptr || otherPtr == currentTarget)
                    continue;

                const osg::Vec3f otherHalfExtents = world->getHalfExtents(otherPtr);
                osg::Vec3f deltaPos = otherPtr.getRefData().getPosition().asVec3() - basePos;
                osg::Vec2f relPos = Misc::rotateVec2f(osg::Vec2f(deltaPos.x(), deltaPos.y()), baseRotZ);
                float dist = deltaPos.length();

                // Ignore actors which are not close enough or come from behind.
                if (dist > maxDistToCheck || relPos.y() < 0)
                    continue;

                // Don't check for a collision if vertical distance is greater then the actor's height.
                if (deltaPos.z() > halfExtents.z() * 2 || deltaPos.z() < -otherHalfExtents.z() * 2)
                    continue;

                osg::Vec3f speed = otherPtr.getClass().getMovementSettings(otherPtr).asVec3() *
                                   otherPtr.getClass().getMaxSpeed(otherPtr);
                float rotZ = otherPtr.getRefData().getPosition().rot[2];
                osg::Vec2f relSpeed = Misc::rotateVec2f(osg::Vec2f(speed.x(), speed.y()), baseRotZ - rotZ) - baseSpeed;

                float collisionDist = minGap + halfExtents.x() + otherHalfExtents.x();
                collisionDist = std::min(collisionDist, relPos.length());

                // Find the earliest `t` when |relPos + relSpeed * t| == collisionDist.
                float vr = relPos.x() * relSpeed.x() + relPos.y() * relSpeed.y();
                float v2 = relSpeed.length2();
                float Dh = vr * vr - v2 * (relPos.length2() - collisionDist * collisionDist);
                if (Dh <= 0 || v2 == 0)
                    continue; // No solution; distance is always >= collisionDist.
                float t = (-vr - std::sqrt(Dh)) / v2;

                if (t < 0 || t > timeToCollision)
                    continue;

                // Check visibility and awareness last as it's expensive.
                if (!MWBase::Environment::get().getWorld()->getLOS(otherPtr, ptr))
                    continue;
                if (!MWBase::Environment::get().getMechanicsManager()->awarenessCheck(otherPtr, ptr))
                    continue;

                timeToCollision = t;
                angleToApproachingActor = std::atan2(deltaPos.x(), deltaPos.y());
                osg::Vec2f posAtT = relPos + relSpeed * t;
                float coef = (posAtT.x() * relSpeed.x() + posAtT.y() * relSpeed.y()) / (collisionDist * collisionDist * maxSpeed);
                coef *= std::clamp((maxDistForPartialAvoiding - dist) / (maxDistForPartialAvoiding - maxDistForStrictAvoiding), 0.f, 1.f);
                movementCorrection = posAtT * coef;
                if (otherPtr.getClass().getCreatureStats(otherPtr).isDead())
                    // In case of dead body still try to go around (it looks natural), but reduce the correction twice.
                    movementCorrection.y() *= 0.5f;
            }

            if (timeToCollision < timeToCheck)
            {
                // Try to evade the nearest collision.
                osg::Vec2f newMovement = origMovement + movementCorrection;
                // Step to the side rather than backward. Otherwise player will be able to push the NPC far away from it's original location.
                newMovement.y() = std::max(newMovement.y(), 0.f);
                newMovement.normalize();
                if (isMoving)
                    newMovement *= origMovement.length(); // Keep the original speed.
                movement.mPosition[0] = newMovement.x();
                movement.mPosition[1] = newMovement.y();
                if (shouldTurnToApproachingActor)
                    zTurn(ptr, angleToApproachingActor);
            }
        }
    }

    void Actors::update (float duration, bool paused)
    {
        if(!paused)
        {
            const float updateEquippedLightInterval = 1.0f;

            if (mTimerUpdateHeadTrack >= 0.3f)
                mTimerUpdateHeadTrack = 0;

            if (mTimerUpdateHello >= 0.25f)
                mTimerUpdateHello = 0;

            if (mTimerDisposeSummonsCorpses >= 0.2f)
                mTimerDisposeSummonsCorpses = 0;

            if (mTimerUpdateEquippedLight >= updateEquippedLightInterval)
                mTimerUpdateEquippedLight = 0;

            // show torches only when there are darkness and no precipitations
            MWBase::World* world = MWBase::Environment::get().getWorld();
            bool showTorches = world->useTorches();

            MWWorld::Ptr player = getPlayer();
            const osg::Vec3f playerPos = player.getRefData().getPosition().asVec3();

            /// \todo move update logic to Actor class where appropriate

            std::map<const MWWorld::Ptr, const std::set<MWWorld::Ptr> > cachedAllies; // will be filled as engageCombat iterates

            bool aiActive = MWBase::Environment::get().getMechanicsManager()->isAIActive();
            int attackedByPlayerId = player.getClass().getCreatureStats(player).getHitAttemptActorId();
            if (attackedByPlayerId != -1)
            {
                const MWWorld::Ptr playerHitAttemptActor = world->searchPtrViaActorId(attackedByPlayerId);

                if (!playerHitAttemptActor.isInCell())
                    player.getClass().getCreatureStats(player).setHitAttemptActorId(-1);
            }
            bool godmode = MWBase::Environment::get().getWorld()->getGodModeState();

             // AI and magic effects update
            for (Actor& actor : mActors)
            {
                const bool isPlayer = actor.getPtr() == player;
                CharacterController& ctrl = actor.getCharacterController();
                MWBase::LuaManager::ActorControls* luaControls =
                    MWBase::Environment::get().getLuaManager()->getActorControls(actor.getPtr());

                const float distSqr = (playerPos - actor.getPtr().getRefData().getPosition().asVec3()).length2();
                // AI processing is only done within given distance to the player.
                bool inProcessingRange = distSqr <= mActorsProcessingRange*mActorsProcessingRange;

                // If dead or no longer in combat, no longer store any actors who attempted to hit us. Also remove for the player.
                if (actor.getPtr() != player && (actor.getPtr().getClass().getCreatureStats(actor.getPtr()).isDead()
                    || !actor.getPtr().getClass().getCreatureStats(actor.getPtr()).getAiSequence().isInCombat()
                    || !inProcessingRange))
                {
                    actor.getPtr().getClass().getCreatureStats(actor.getPtr()).setHitAttemptActorId(-1);
                    if (player.getClass().getCreatureStats(player).getHitAttemptActorId() == actor.getPtr().getClass().getCreatureStats(actor.getPtr()).getActorId())
                        player.getClass().getCreatureStats(player).setHitAttemptActorId(-1);
                }

                const Misc::TimerStatus engageCombatTimerStatus = actor.updateEngageCombatTimer(duration);

                // For dead actors we need to update looping spell particles
                if (actor.getPtr().getClass().getCreatureStats(actor.getPtr()).isDead())
                {
                    // They can be added during the death animation
                    if (!actor.getPtr().getClass().getCreatureStats(actor.getPtr()).isDeathAnimationFinished())
                        adjustMagicEffects(actor.getPtr(), duration);
                    ctrl.updateContinuousVfx();
                }
                else
                {
                    bool cellChanged = world->hasCellChanged();
                    const MWWorld::Ptr actorPtr = actor.getPtr(); // make a copy of the map key to avoid it being invalidated when the player teleports
                    updateActor(actorPtr, duration);

                    // Looping magic VFX update
                    // Note: we need to do this before any of the animations are updated.
                    // Reaching the text keys may trigger Hit / Spellcast (and as such, particles),
                    // so updating VFX immediately after that would just remove the particle effects instantly.
                    // There needs to be a magic effect update in between.
                    ctrl.updateContinuousVfx();

                    if (!cellChanged && world->hasCellChanged())
                    {
                        return; // for now abort update of the old cell when cell changes by teleportation magic effect
                                // a better solution might be to apply cell changes at the end of the frame
                    }
                    if (aiActive && inProcessingRange)
                    {
                        if (engageCombatTimerStatus == Misc::TimerStatus::Elapsed)
                        {
                            if (!isPlayer)
                                adjustCommandedActor(actor.getPtr());

                            for (const Actor& otherActor : mActors)
                            {
                                if (otherActor.getPtr() == actor.getPtr() || isPlayer) // player is not AI-controlled
                                    continue;
                                engageCombat(actor.getPtr(), otherActor.getPtr(), cachedAllies, otherActor.getPtr() == player);
                            }
                        }
                        if (mTimerUpdateHeadTrack == 0)
                        {
                            float sqrHeadTrackDistance = std::numeric_limits<float>::max();
                            MWWorld::Ptr headTrackTarget;

                            MWMechanics::CreatureStats& stats = actor.getPtr().getClass().getCreatureStats(actor.getPtr());
                            bool firstPersonPlayer = isPlayer && world->isFirstPerson();
  
                            // 1. Unconsious actor can not track target
                            // 2. Actors in combat and pursue mode do not bother to headtrack anyone except their target
                            // 3. Player character does not use headtracking in the 1st-person view
                            if (!stats.getKnockedDown() && !firstPersonPlayer)
                            {
                                bool inCombatOrPursue = stats.getAiSequence().isInCombat() || stats.getAiSequence().isInPursuit();
                                if (inCombatOrPursue)
                                {
                                    auto activePackageTarget = stats.getAiSequence().getActivePackage().getTarget();
                                    if (!activePackageTarget.isEmpty())
                                    {
                                        // Track the specified target of package.
                                        updateHeadTracking(actor.getPtr(), activePackageTarget, headTrackTarget, sqrHeadTrackDistance, inCombatOrPursue);
                                    }
                                }
                                else
                                {
                                    // Find something nearby.
                                    for (const Actor& otherActor : mActors)
                                    {
                                        if (otherActor.getPtr() == actor.getPtr())
                                            continue;

                                        updateHeadTracking(actor.getPtr(), otherActor.getPtr(), headTrackTarget, sqrHeadTrackDistance, inCombatOrPursue);
                                    }
                                }
                            }

                            ctrl.setHeadTrackTarget(headTrackTarget);
                        }

                        if (actor.getPtr().getClass().isNpc() && actor.getPtr() != player)
                            updateCrimePursuit(actor.getPtr(), duration);

                        if (actor.getPtr() != player)
                        {
                            CreatureStats &stats = actor.getPtr().getClass().getCreatureStats(actor.getPtr());
                            if (isConscious(actor.getPtr()) && !(luaControls && luaControls->mDisableAI))
                            {
                                stats.getAiSequence().execute(actor.getPtr(), ctrl, duration);
                                updateGreetingState(actor.getPtr(), actor, mTimerUpdateHello > 0);
                                playIdleDialogue(actor.getPtr());
                                updateMovementSpeed(actor.getPtr());
                            }
                        }
                    }
                    else if (aiActive && actor.getPtr() != player && isConscious(actor.getPtr()) && !(luaControls && luaControls->mDisableAI))
                    {
                        CreatureStats &stats = actor.getPtr().getClass().getCreatureStats(actor.getPtr());
                        stats.getAiSequence().execute(actor.getPtr(), ctrl, duration, /*outOfRange*/true);
                    }

                    if (inProcessingRange && actor.getPtr().getClass().isNpc())
                    {
                        // We can not update drowning state for actors outside of AI distance - they can not resurface to breathe
                        updateDrowning(actor.getPtr(), duration, ctrl.isKnockedOut(), isPlayer);
                    }
                    if (mTimerUpdateEquippedLight == 0 && actor.getPtr().getClass().hasInventoryStore(actor.getPtr()))
                        updateEquippedLight(actor.getPtr(), updateEquippedLightInterval, showTorches);

                    if (luaControls && isConscious(actor.getPtr()))
                    {
                        Movement& mov = actor.getPtr().getClass().getMovementSettings(actor.getPtr());
                        CreatureStats& stats = actor.getPtr().getClass().getCreatureStats(actor.getPtr());
                        float speedFactor = isPlayer ? 1.f : mov.mSpeedFactor;
                        osg::Vec2f movement = osg::Vec2f(mov.mPosition[0], mov.mPosition[1]) * speedFactor;
                        float rotationX = mov.mRotation[0];
                        float rotationZ = mov.mRotation[2];
                        bool jump = mov.mPosition[2] == 1;
                        bool runFlag = stats.getMovementFlag(MWMechanics::CreatureStats::Flag_Run);
                        bool attackingOrSpell = stats.getAttackingOrSpell();
                        if (luaControls->mChanged)
                        {
                            mov.mPosition[0] = luaControls->mSideMovement;
                            mov.mPosition[1] = luaControls->mMovement;
                            mov.mPosition[2] = luaControls->mJump ? 1 : 0;
                            mov.mRotation[0] = luaControls->mPitchChange;
                            mov.mRotation[1] = 0;
                            mov.mRotation[2] = luaControls->mYawChange;
                            mov.mSpeedFactor = osg::Vec2(luaControls->mMovement, luaControls->mSideMovement).length();
                            stats.setMovementFlag(MWMechanics::CreatureStats::Flag_Run, luaControls->mRun);
                            stats.setAttackingOrSpell((luaControls->mUse & 1) == 1);
                            luaControls->mChanged = false;
                        }
                        luaControls->mSideMovement = movement.x();
                        luaControls->mMovement = movement.y();
                        luaControls->mPitchChange = rotationX;
                        luaControls->mYawChange = rotationZ;
                        luaControls->mJump = jump;
                        luaControls->mRun = runFlag;
                        luaControls->mUse = attackingOrSpell ? luaControls->mUse | 1 : luaControls->mUse & ~1;
                    }
                }
            }

            static const bool avoidCollisions = Settings::Manager::getBool("NPCs avoid collisions", "Game");
            if (avoidCollisions)
                predictAndAvoidCollisions(duration);

            mTimerUpdateHeadTrack += duration;
            mTimerUpdateEquippedLight += duration;
            mTimerUpdateHello += duration;
            mTimerDisposeSummonsCorpses += duration;

            // Animation/movement update
            CharacterController* playerCharacter = nullptr;
            for (Actor& actor : mActors)
            {
                const float dist = (playerPos - actor.getPtr().getRefData().getPosition().asVec3()).length();
                const bool isPlayer = actor.getPtr() == player;
                CreatureStats &stats = actor.getPtr().getClass().getCreatureStats(actor.getPtr());
                // Actors with active AI should be able to move.
                bool alwaysActive = false;
                if (!isPlayer && isConscious(actor.getPtr()) && !stats.isParalyzed())
                {
                    MWMechanics::AiSequence& seq = stats.getAiSequence();
                    alwaysActive = !seq.isEmpty() && seq.getActivePackage().alwaysActive();
                }
                bool inRange = isPlayer || dist <= mActorsProcessingRange || alwaysActive;
                int activeFlag = 1; // Can be changed back to '2' to keep updating bounding boxes off screen (more accurate, but slower)
                if (isPlayer)
                    activeFlag = 2;
                int active = inRange ? activeFlag : 0;

                CharacterController& ctrl = actor.getCharacterController();
                ctrl.setActive(active);

                if (!inRange)
                {
                    actor.getPtr().getRefData().getBaseNode()->setNodeMask(0);
                    world->setActorCollisionMode(actor.getPtr(), false, false);
                    continue;
                }
                else if (!isPlayer)
                {
                    actor.getPtr().getRefData().getBaseNode()->setNodeMask(MWRender::Mask_Actor);
                    if (!actor.getPositionAdjusted())
                    {
                        actor.getPtr().getClass().adjustPosition(actor.getPtr(), false);
                        actor.setPositionAdjusted(true);
                    }
                }

                const bool isDead = actor.getPtr().getClass().getCreatureStats(actor.getPtr()).isDead();
                if (!isDead && (!godmode || !isPlayer) && actor.getPtr().getClass().getCreatureStats(actor.getPtr()).isParalyzed())
                    ctrl.skipAnim();

                // Handle player last, in case a cell transition occurs by casting a teleportation spell
                // (would invalidate the iterator)
                if (actor.getPtr() == getPlayer())
                {
                    playerCharacter = &ctrl;
                    continue;
                }

                world->setActorCollisionMode(actor.getPtr(), true, !actor.getPtr().getClass().getCreatureStats(actor.getPtr()).isDeathAnimationFinished());
                ctrl.update(duration);

                updateVisibility(actor.getPtr(), ctrl);
            }

            if (playerCharacter)
            {
                MWBase::Environment::get().getWorld()->applyDeferredPreviewRotationToPlayer(duration);
                playerCharacter->update(duration);
                playerCharacter->setVisibility(1.f);
            }

            for (const Actor& actor : mActors)
            {
                const MWWorld::Class &cls = actor.getPtr().getClass();
                CreatureStats &stats = cls.getCreatureStats(actor.getPtr());

                //KnockedOutOneFrameLogic
                //Used for "OnKnockedOut" command
                //Put here to ensure that it's run for PRECISELY one frame.
                if (stats.getKnockedDown() && !stats.getKnockedDownOneFrame() && !stats.getKnockedDownOverOneFrame())
                { //Start it for one frame if nessesary
                    stats.setKnockedDownOneFrame(true);
                }
                else if (stats.getKnockedDownOneFrame() && !stats.getKnockedDownOverOneFrame())
                { //Turn off KnockedOutOneframe
                    stats.setKnockedDownOneFrame(false);
                    stats.setKnockedDownOverOneFrame(true);
                }
            }

            killDeadActors();
            updateSneaking(playerCharacter, duration);
        }

        updateCombatMusic();
    }

    void Actors::notifyDied(const MWWorld::Ptr &actor)
    {
        actor.getClass().getCreatureStats(actor).notifyDied();

        ++mDeathCount[Misc::StringUtils::lowerCase(actor.getCellRef().getRefId())];
    }

    void Actors::resurrect(const MWWorld::Ptr &ptr)
    {
        const auto iter = mIndex.find(ptr.mRef);
        if (iter != mIndex.end())
        {
            if (iter->second->getCharacterController().isDead())
            {
                // Actor has been resurrected. Notify the CharacterController and re-enable collision.
                MWBase::Environment::get().getWorld()->enableActorCollision(iter->second->getPtr(), true);
                iter->second->getCharacterController().resurrect();
            }
        }
    }

    void Actors::killDeadActors()
    {
        for (Actor& actor : mActors)
        {
            const MWWorld::Class &cls = actor.getPtr().getClass();
            CreatureStats &stats = cls.getCreatureStats(actor.getPtr());

            if(!stats.isDead())
                continue;

            MWBase::Environment::get().getWorld()->removeActorPath(actor.getPtr());
            CharacterController::KillResult killResult = actor.getCharacterController().kill();
            if (killResult == CharacterController::Result_DeathAnimStarted)
            {
                // Play dying words
                // Note: It's not known whether the soundgen tags scream, roar, and moan are reliable
                // for NPCs since some of the npc death animation files are missing them.
                MWBase::Environment::get().getDialogueManager()->say(actor.getPtr(), "hit");

                // Apply soultrap
                if (actor.getPtr().getType() == ESM::Creature::sRecordId)
                    soulTrap(actor.getPtr());

                if (cls.isEssential(actor.getPtr()))
                    MWBase::Environment::get().getWindowManager()->messageBox("#{sKilledEssential}");
            }
            else if (killResult == CharacterController::Result_DeathAnimJustFinished)
            {
                const bool isPlayer = actor.getPtr() == getPlayer();
                notifyDied(actor.getPtr());

                // Reset magic effects and recalculate derived effects
                // One case where we need this is to make sure bound items are removed upon death
                float vampirism = stats.getMagicEffects().get(ESM::MagicEffect::Vampirism).getMagnitude();
                stats.getActiveSpells().clear(actor.getPtr());
                // Make sure spell effects are removed
                purgeSpellEffects(stats.getActorId());

                stats.getMagicEffects().add(ESM::MagicEffect::Vampirism, vampirism);

                if (isPlayer)
                {
                    //player's death animation is over
                    MWBase::Environment::get().getStateManager()->askLoadRecent();
                    // Play Death Music if it was the player dying
                    MWBase::Environment::get().getSoundManager()->streamMusic("Special/MW_Death.mp3");
                }
                else
                {
                    // NPC death animation is over, disable actor collision
                    MWBase::Environment::get().getWorld()->enableActorCollision(actor.getPtr(), false);
                }
            }
        }
    }

    void Actors::cleanupSummonedCreature (MWMechanics::CreatureStats& casterStats, int creatureActorId)
    {
        MWWorld::Ptr ptr = MWBase::Environment::get().getWorld()->searchPtrViaActorId(creatureActorId);
        if (!ptr.isEmpty())
        {
            MWBase::Environment::get().getWorld()->deleteObject(ptr);

            const ESM::Static* fx = MWBase::Environment::get().getWorld()->getStore().get<ESM::Static>()
                    .search("VFX_Summon_End");
            if (fx)
                MWBase::Environment::get().getWorld()->spawnEffect("meshes\\" + fx->mModel,
                    "", ptr.getRefData().getPosition().asVec3());

            // Remove the summoned creature's summoned creatures as well
            MWMechanics::CreatureStats& stats = ptr.getClass().getCreatureStats(ptr);
            auto& creatureMap = stats.getSummonedCreatureMap();
            for (const auto& creature : creatureMap)
                cleanupSummonedCreature(stats, creature.second);
            creatureMap.clear();
        }
        else if (creatureActorId != -1)
        {
            // We didn't find the creature. It's probably in an inactive cell.
            // Add to graveyard so we can delete it when the cell becomes active.
            std::vector<int>& graveyard = casterStats.getSummonedCreatureGraveyard();
            graveyard.push_back(creatureActorId);
        }

        purgeSpellEffects(creatureActorId);
    }

    void Actors::purgeSpellEffects(int casterActorId)
    {
        for (const Actor& actor : mActors)
        {
            MWMechanics::ActiveSpells& spells = actor.getPtr().getClass().getCreatureStats(actor.getPtr()).getActiveSpells();
            spells.purge(actor.getPtr(), casterActorId);
        }
    }

    void Actors::rest(double hours, bool sleep)
    {
        float duration = hours * 3600.f;
        float timeScale = MWBase::Environment::get().getWorld()->getTimeScaleFactor();
        if (timeScale != 0.f)
            duration /= timeScale;

        const MWWorld::Ptr player = MWBase::Environment::get().getWorld()->getPlayerPtr();
        const osg::Vec3f playerPos = player.getRefData().getPosition().asVec3();

        for (const Actor& actor : mActors)
        {
            if (actor.getPtr().getClass().getCreatureStats(actor.getPtr()).isDead())
            {
                adjustMagicEffects(actor.getPtr(), duration);
                continue;
            }

            if (!sleep || actor.getPtr() == player)
                restoreDynamicStats(actor.getPtr(), hours, sleep);

            if ((!actor.getPtr().getRefData().getBaseNode()) ||
                    (playerPos - actor.getPtr().getRefData().getPosition().asVec3()).length2() > mActorsProcessingRange*mActorsProcessingRange)
                continue;

            adjustMagicEffects (actor.getPtr(), duration);

            MWRender::Animation* animation = MWBase::Environment::get().getWorld()->getAnimation(actor.getPtr());
            if (animation)
            {
                animation->removeEffects();
                MWBase::Environment::get().getWorld()->applyLoopingParticles(actor.getPtr());
            }
        }

        fastForwardAi();
    }

    void Actors::updateSneaking(CharacterController* ctrl, float duration)
    {
        if (!ctrl)
        {
            MWBase::Environment::get().getWindowManager()->setSneakVisibility(false);
            return;
        }

        MWWorld::Ptr player = getPlayer();

        if (!MWBase::Environment::get().getMechanicsManager()->isSneaking(player))
        {
            MWBase::Environment::get().getWindowManager()->setSneakVisibility(false);
            return;
        }

        MWBase::World* world = MWBase::Environment::get().getWorld();
        const MWWorld::Store<ESM::GameSetting>& gmst = world->getStore().get<ESM::GameSetting>();
        static const float fSneakUseDist = gmst.find("fSneakUseDist")->mValue.getFloat();
        static const float fSneakUseDelay = gmst.find("fSneakUseDelay")->mValue.getFloat();

        if (mSneakTimer >= fSneakUseDelay)
            mSneakTimer = 0.f;

        if (mSneakTimer == 0.f)
        {
            // Set when an NPC is within line of sight and distance, but is still unaware. Used for skill progress.
            bool avoidedNotice = false;
            bool detected = false;

            std::vector<MWWorld::Ptr> observers;
            osg::Vec3f position(player.getRefData().getPosition().asVec3());
            float radius = std::min(fSneakUseDist, mActorsProcessingRange);
            getObjectsInRange(position, radius, observers);

            std::set<MWWorld::Ptr> sidingActors;
            getActorsSidingWith(player, sidingActors);

            for (const MWWorld::Ptr &observer : observers)
            {
                if (observer == player || observer.getClass().getCreatureStats(observer).isDead())
                    continue;

                if (sidingActors.find(observer) != sidingActors.cend())
                    continue;

                if (world->getLOS(player, observer))
                {
                    if (MWBase::Environment::get().getMechanicsManager()->awarenessCheck(player, observer))
                    {
                        detected = true;
                        avoidedNotice = false;
                        MWBase::Environment::get().getWindowManager()->setSneakVisibility(false);
                        break;
                    }
                    else
                    {
                        avoidedNotice = true;
                    }
                }
            }

            if (mSneakSkillTimer >= fSneakUseDelay)
                mSneakSkillTimer = 0.f;

            if (avoidedNotice && mSneakSkillTimer == 0.f)
                player.getClass().skillUsageSucceeded(player, ESM::Skill::Sneak, 0);

            if (!detected)
                MWBase::Environment::get().getWindowManager()->setSneakVisibility(true);
        }

        mSneakTimer += duration;
        mSneakSkillTimer += duration;
    }

    int Actors::getHoursToRest(const MWWorld::Ptr &ptr) const
    {
        float healthPerHour, magickaPerHour;
        getRestorationPerHourOfSleep(ptr, healthPerHour, magickaPerHour);

        CreatureStats& stats = ptr.getClass().getCreatureStats(ptr);
        bool stunted = stats.getMagicEffects ().get(ESM::MagicEffect::StuntedMagicka).getMagnitude() > 0;

        float healthHours  = healthPerHour > 0
                             ? (stats.getHealth().getModified() - stats.getHealth().getCurrent()) / healthPerHour
                             : 1.0f;
        float magickaHours = magickaPerHour > 0 && !stunted
                              ? (stats.getMagicka().getModified() - stats.getMagicka().getCurrent()) / magickaPerHour
                              : 1.0f;

        int autoHours = static_cast<int>(std::ceil(std::max(1.f, std::max(healthHours, magickaHours))));
        return autoHours;
    }

    int Actors::countDeaths (const std::string& id) const
    {
        std::map<std::string, int>::const_iterator iter = mDeathCount.find(id);
        if(iter != mDeathCount.end())
            return iter->second;
        return 0;
    }

    void Actors::forceStateUpdate(const MWWorld::Ptr & ptr)
    {
        const auto iter = mIndex.find(ptr.mRef);
        if (iter != mIndex.end())
            iter->second->getCharacterController().forceStateUpdate();
    }

    bool Actors::playAnimationGroup(const MWWorld::Ptr& ptr, const std::string& groupName, int mode, int number, bool persist)
    {
        const auto iter = mIndex.find(ptr.mRef);
        if(iter != mIndex.end())
        {
            return iter->second->getCharacterController().playGroup(groupName, mode, number, persist);
        }
        else
        {
            Log(Debug::Warning) << "Warning: Actors::playAnimationGroup: Unable to find " << ptr.getCellRef().getRefId();
            return false;
        }
    }
    void Actors::skipAnimation(const MWWorld::Ptr& ptr)
    {
        const auto iter = mIndex.find(ptr.mRef);
        if (iter != mIndex.end())
            iter->second->getCharacterController().skipAnim();
    }

    bool Actors::checkAnimationPlaying(const MWWorld::Ptr& ptr, const std::string& groupName)
    {
        const auto iter = mIndex.find(ptr.mRef);
        if(iter != mIndex.end())
            return iter->second->getCharacterController().isAnimPlaying(groupName);
        return false;
    }

    void Actors::persistAnimationStates()
    {
        for (Actor& actor : mActors)
            actor.getCharacterController().persistAnimationState();
    }

    void Actors::getObjectsInRange(const osg::Vec3f& position, float radius, std::vector<MWWorld::Ptr>& out)
    {
        for (const Actor& actor : mActors)
        {
            if ((actor.getPtr().getRefData().getPosition().asVec3() - position).length2() <= radius*radius)
                out.push_back(actor.getPtr());
        }
    }

    bool Actors::isAnyObjectInRange(const osg::Vec3f& position, float radius)
    {
        for (const Actor& actor : mActors)
        {
            if ((actor.getPtr().getRefData().getPosition().asVec3() - position).length2() <= radius*radius)
                return true;
        }

        return false;
    }

    std::vector<MWWorld::Ptr> Actors::getActorsSidingWith(const MWWorld::Ptr& actorPtr)
    {
        std::vector<MWWorld::Ptr> list;
        for (const Actor& actor : mActors)
        {
            const MWWorld::Ptr& iteratedActor = actor.getPtr();
            if (iteratedActor == getPlayer())
                continue;

            const bool sameActor = (iteratedActor == actorPtr);

            const CreatureStats &stats = iteratedActor.getClass().getCreatureStats(iteratedActor);
            if (stats.isDead())
                continue;

            // An actor counts as siding with this actor if Follow or Escort is the current AI package, or there are only Wander packages before the Follow/Escort package
            // Actors that are targeted by this actor's Follow or Escort packages also side with them
            for (const auto& package : stats.getAiSequence())
            {
                if (package->sideWithTarget() && !package->getTarget().isEmpty())
                {
                    if (sameActor)
                    {
                        list.push_back(package->getTarget());
                    }
                    else if (package->getTarget() == actorPtr)
                    {
                        list.push_back(iteratedActor);
                    }
                    break;
                }
                else if (package->getTypeId() > AiPackageTypeId::Wander && package->getTypeId() <= AiPackageTypeId::Activate) // Don't count "fake" package types
                    break;
            }
        }
        return list;
    }

    std::vector<MWWorld::Ptr> Actors::getActorsFollowing(const MWWorld::Ptr& actorPtr)
    {
        std::vector<MWWorld::Ptr> list;
        forEachFollowingPackage(mActors, actorPtr, getPlayer(), [&] (const Actor& actor, const std::shared_ptr<AiPackage>& package)
        {
            if (package->followTargetThroughDoors() && package->getTarget() == actorPtr)
                list.push_back(actor.getPtr());
            else if (package->getTypeId() != AiPackageTypeId::Combat && package->getTypeId() != AiPackageTypeId::Wander)
                return false;
            return true;
        });
        return list;
    }

    void Actors::getActorsFollowing(const MWWorld::Ptr &actor, std::set<MWWorld::Ptr>& out) {
        auto followers = getActorsFollowing(actor);
        for(const MWWorld::Ptr &follower : followers)
            if (out.insert(follower).second)
                getActorsFollowing(follower, out);
    }

    void Actors::getActorsSidingWith(const MWWorld::Ptr &actor, std::set<MWWorld::Ptr>& out) {
        auto followers = getActorsSidingWith(actor);
        for(const MWWorld::Ptr &follower : followers)
            if (out.insert(follower).second)
                getActorsSidingWith(follower, out);
    }

    void Actors::getActorsSidingWith(const MWWorld::Ptr &actor, std::set<MWWorld::Ptr>& out, std::map<const MWWorld::Ptr, const std::set<MWWorld::Ptr> >& cachedAllies) {
        // If we have already found actor's allies, use the cache
        std::map<const MWWorld::Ptr, const std::set<MWWorld::Ptr> >::const_iterator search = cachedAllies.find(actor);
        if (search != cachedAllies.end())
            out.insert(search->second.begin(), search->second.end());
        else
        {
            auto followers = getActorsSidingWith(actor);
            for (const MWWorld::Ptr &follower : followers)
                if (out.insert(follower).second)
                    getActorsSidingWith(follower, out, cachedAllies);

            // Cache ptrs and their sets of allies
            cachedAllies.insert(std::make_pair(actor, out));
            for (const MWWorld::Ptr &iter : out)
            {
                search = cachedAllies.find(iter);
                if (search == cachedAllies.end())
                    cachedAllies.insert(std::make_pair(iter, out));
            }
        }
    }

    std::vector<int> Actors::getActorsFollowingIndices(const MWWorld::Ptr &actor)
    {
        std::vector<int> list;
        forEachFollowingPackage(mActors, actor, getPlayer(), [&] (const Actor&, const std::shared_ptr<AiPackage>& package)
        {
            if (package->followTargetThroughDoors() && package->getTarget() == actor)
            {
                list.push_back(static_cast<const AiFollow*>(package.get())->getFollowIndex());
                return false;
            }
            else if (package->getTypeId() != AiPackageTypeId::Combat && package->getTypeId() != AiPackageTypeId::Wander)
                return false;
            return true;
        });
        return list;
    }

    std::map<int, MWWorld::Ptr> Actors::getActorsFollowingByIndex(const MWWorld::Ptr &actor)
    {
        std::map<int, MWWorld::Ptr> map;
        forEachFollowingPackage(mActors, actor, getPlayer(), [&] (const Actor& otherActor, const std::shared_ptr<AiPackage>& package)
        {
            if (package->followTargetThroughDoors() && package->getTarget() == actor)
            {
                int index = static_cast<const AiFollow*>(package.get())->getFollowIndex();
                map[index] = otherActor.getPtr();
                return false;
            }
            else if (package->getTypeId() != AiPackageTypeId::Combat && package->getTypeId() != AiPackageTypeId::Wander)
                return false;
            return true;
        });
        return map;
    }

    std::vector<MWWorld::Ptr> Actors::getActorsFighting(const MWWorld::Ptr& actor) {
        std::vector<MWWorld::Ptr> list;
        std::vector<MWWorld::Ptr> neighbors;
        osg::Vec3f position (actor.getRefData().getPosition().asVec3());
        getObjectsInRange(position, mActorsProcessingRange, neighbors);
        for(const MWWorld::Ptr& neighbor : neighbors)
        {
            if (neighbor == actor)
                continue;

            const CreatureStats &stats = neighbor.getClass().getCreatureStats(neighbor);
            if (stats.isDead())
                continue;

            if (stats.getAiSequence().isInCombat(actor))
                list.push_back(neighbor);
        }
        return list;
    }

    std::vector<MWWorld::Ptr> Actors::getEnemiesNearby(const MWWorld::Ptr& actor)
    {
        std::vector<MWWorld::Ptr> list;
        std::vector<MWWorld::Ptr> neighbors;
        osg::Vec3f position (actor.getRefData().getPosition().asVec3());
        getObjectsInRange(position, mActorsProcessingRange, neighbors);

        std::set<MWWorld::Ptr> followers;
        getActorsFollowing(actor, followers);
        for (auto neighbor = neighbors.begin(); neighbor != neighbors.end(); ++neighbor)
        {
            const CreatureStats &stats = neighbor->getClass().getCreatureStats(*neighbor);
            if (stats.isDead() || *neighbor == actor || neighbor->getClass().isPureWaterCreature(*neighbor))
                continue;

            const bool isFollower = followers.find(*neighbor) != followers.end();

            if (stats.getAiSequence().isInCombat(actor) || (MWBase::Environment::get().getMechanicsManager()->isAggressive(*neighbor, actor) && !isFollower))
                list.push_back(*neighbor);
        }
        return list;
    }


    void Actors::write (ESM::ESMWriter& writer, Loading::Listener& listener) const
    {
        writer.startRecord(ESM::REC_DCOU);
        for (std::map<std::string, int>::const_iterator it = mDeathCount.begin(); it != mDeathCount.end(); ++it)
        {
            writer.writeHNString("ID__", it->first);
            writer.writeHNT ("COUN", it->second);
        }
        writer.endRecord(ESM::REC_DCOU);
    }

    void Actors::readRecord (ESM::ESMReader& reader, uint32_t type)
    {
        if (type == ESM::REC_DCOU)
        {
            while (reader.isNextSub("ID__"))
            {
                std::string id = reader.getHString();
                int count;
                reader.getHNT(count, "COUN");
                if (MWBase::Environment::get().getWorld()->getStore().find(id))
                    mDeathCount[id] = count;
            }
        }
    }

    void Actors::clear()
    {
        mIndex.clear();
        mActors.clear();
        mDeathCount.clear();
    }

    void Actors::updateMagicEffects(const MWWorld::Ptr &ptr)
    {
        adjustMagicEffects(ptr, 0.f);
    }

    bool Actors::isReadyToBlock(const MWWorld::Ptr &ptr) const
    {
        const auto it = mIndex.find(ptr.mRef);
        if (it == mIndex.end())
            return false;

        return it->second->getCharacterController().isReadyToBlock();
    }

    bool Actors::isCastingSpell(const MWWorld::Ptr &ptr) const
    {
        const auto it = mIndex.find(ptr.mRef);
        if (it == mIndex.end())
            return false;

        return it->second->getCharacterController().isCastingSpell();
    }

    bool Actors::isAttackingOrSpell(const MWWorld::Ptr& ptr) const
    {
        const auto it = mIndex.find(ptr.mRef);
        if (it == mIndex.end())
            return false;

        return it->second->getCharacterController().isAttackingOrSpell();
    }

    int Actors::getGreetingTimer(const MWWorld::Ptr& ptr) const
    {
        const auto it = mIndex.find(ptr.mRef);
        if (it == mIndex.end())
            return 0;

        return it->second->getGreetingTimer();
    }

    float Actors::getAngleToPlayer(const MWWorld::Ptr& ptr) const
    {
        const auto it = mIndex.find(ptr.mRef);
        if (it == mIndex.end())
            return 0.f;

        return it->second->getAngleToPlayer();
    }

    GreetingState Actors::getGreetingState(const MWWorld::Ptr& ptr) const
    {
        const auto it = mIndex.find(ptr.mRef);
        if (it == mIndex.end())
            return Greet_None;

        return it->second->getGreetingState();
    }

    bool Actors::isTurningToPlayer(const MWWorld::Ptr& ptr) const
    {
        const auto it = mIndex.find(ptr.mRef);
        if (it == mIndex.end())
            return false;

        return it->second->isTurningToPlayer();
    }

    void Actors::fastForwardAi()
    {
        if (!MWBase::Environment::get().getMechanicsManager()->isAIActive())
            return;

        for (const Actor& actor : mActors)
        {
            const MWWorld::Ptr ptr = actor.getPtr();
            if (ptr == getPlayer()
                    || !isConscious(ptr)
                    || ptr.getClass().getCreatureStats(ptr).isParalyzed())
                continue;
            MWMechanics::AiSequence& seq = ptr.getClass().getCreatureStats(ptr).getAiSequence();
            seq.fastForward(ptr);
        }
    }
}