/*
 * This file is part of the TrinityCore Project. See AUTHORS file for Copyright information
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the
 * Free Software Foundation; either version 2 of the License, or (at your
 * option) any later version.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program. If not, see <http://www.gnu.org/licenses/>.
 */

#include "SmartAI.h"
#include "AreaTrigger.h"
#include "ConditionMgr.h"
#include "Creature.h"
#include "CreatureGroups.h"
#include "DB2Structure.h"
#include "GameObject.h"
#include "Group.h"
#include "Log.h"
#include "MotionMaster.h"
#include "ObjectAccessor.h"
#include "PetDefines.h"
#include "Player.h"
#include "ScriptMgr.h"
#include "Vehicle.h"
#include "WaypointManager.h"

SmartAI::SmartAI(Creature* creature, uint32 scriptId) : CreatureAI(creature, scriptId), _charmed(false), _followCreditType(0), _followArrivedTimer(0), _followCredit(0), _followArrivedEntry(0), _followDistance(0.f), _followAngle(0.f),
    _escortState(SMART_ESCORT_NONE), _escortNPCFlags(0), _escortInvokerCheckTimer(1000), _currentWaypointNodeId(0), _waypointReached(false), _waypointPauseTimer(0), _waypointPauseForced(false), _repeatWaypointPath(false),
    _OOCReached(false), _waypointPathEnded(false), _run(true), _evadeDisabled(false), _canCombatMove(true), _invincibilityHPLevel(0), _despawnTime(0), _despawnState(0), _vehicleConditionsTimer(0),
    _gossipReturn(false), _escortQuestId(0)
{
    _vehicleConditions = sConditionMgr->HasConditionsForNotGroupedEntry(CONDITION_SOURCE_TYPE_CREATURE_TEMPLATE_VEHICLE, creature->GetEntry());
}

bool SmartAI::IsAIControlled() const
{
    return !_charmed;
}

void SmartAI::StartPath(uint32 pathId/* = 0*/, bool repeat/* = false*/, Unit* invoker/* = nullptr*/, uint32 nodeId/* = 0*/,
    Optional<Scripting::v2::ActionResultSetter<MovementStopReason>>&& scriptResult/* = {}*/)
{
    if (HasEscortState(SMART_ESCORT_ESCORTING))
        StopPath();

    if (!pathId)
        return;

    WaypointPath const* path = LoadPath(pathId);
    if (!path)
        return;

    _currentWaypointNodeId = nodeId;
    _waypointPathEnded = false;

    _repeatWaypointPath = repeat;

    // Do not use AddEscortState, removing everything from previous
    _escortState = SMART_ESCORT_ESCORTING;

    if (invoker && invoker->GetTypeId() == TYPEID_PLAYER)
    {
        _escortNPCFlags = me->GetNpcFlags();
        me->ReplaceAllNpcFlags(UNIT_NPC_FLAG_NONE);
    }

    me->GetMotionMaster()->MovePath(pathId, _repeatWaypointPath, {}, {}, MovementWalkRunSpeedSelectionMode::Default, {}, {}, {}, {}, true, std::move(scriptResult));
}

WaypointPath const* SmartAI::LoadPath(uint32 entry)
{
    if (HasEscortState(SMART_ESCORT_ESCORTING))
        return nullptr;

    WaypointPath const* path = sWaypointMgr->GetPath(entry);
    if (!path || path->Nodes.empty())
    {
        GetScript()->SetPathId(0);
        return nullptr;
    }

    GetScript()->SetPathId(entry);
    return path;
}

void SmartAI::PausePath(uint32 delay, bool forced)
{
    if (!HasEscortState(SMART_ESCORT_ESCORTING))
    {
        me->PauseMovement(delay, MOTION_SLOT_DEFAULT, forced);
        if (me->GetMotionMaster()->GetCurrentMovementGeneratorType() == WAYPOINT_MOTION_TYPE)
        {
            std::pair<uint32, uint32> waypointInfo = me->GetCurrentWaypointInfo();
            GetScript()->ProcessEventsFor(SMART_EVENT_WAYPOINT_PAUSED, nullptr, waypointInfo.first, waypointInfo.second);
        }
        return;
    }

    if (HasEscortState(SMART_ESCORT_PAUSED))
    {
        TC_LOG_ERROR("scripts.ai.sai", "SmartAI::PausePath: Creature wanted to pause waypoint (current waypoint: {}) movement while already paused, ignoring. ({})", _currentWaypointNodeId, me->GetGUID().ToString());
        return;
    }

    _waypointPauseTimer = delay;

    if (forced)
    {
        _waypointPauseForced = forced;
        SetRun(_run);
        me->PauseMovement();
        me->SetHomePosition(me->GetPosition());
    }
    else
        _waypointReached = false;

    AddEscortState(SMART_ESCORT_PAUSED);
    GetScript()->ProcessEventsFor(SMART_EVENT_WAYPOINT_PAUSED, nullptr, _currentWaypointNodeId, GetScript()->GetPathId());
}

bool SmartAI::CanResumePath()
{
    if (!HasEscortState(SMART_ESCORT_ESCORTING))
    {
        // The whole resume logic doesn't support this case
        return false;
    }

    return HasEscortState(SMART_ESCORT_PAUSED);
}

void SmartAI::StopPath(uint32 DespawnTime, uint32 quest, bool fail)
{
    if (!HasEscortState(SMART_ESCORT_ESCORTING))
    {
        std::pair<uint32, uint32> waypointInfo = { 0, 0 };
        if (me->GetMotionMaster()->GetCurrentMovementGeneratorType() == WAYPOINT_MOTION_TYPE)
            waypointInfo = me->GetCurrentWaypointInfo();

        if (_despawnState != 2)
            SetDespawnTime(DespawnTime);

        me->GetMotionMaster()->MoveIdle();

        if (waypointInfo.second)
            GetScript()->ProcessEventsFor(SMART_EVENT_WAYPOINT_STOPPED, nullptr, waypointInfo.first, waypointInfo.second);

        if (!fail)
        {
            if (waypointInfo.second)
                GetScript()->ProcessEventsFor(SMART_EVENT_WAYPOINT_ENDED, nullptr, waypointInfo.first, waypointInfo.second);
            if (_despawnState == 1)
                StartDespawn();
        }
        return;
    }

    if (quest)
        _escortQuestId = quest;

    if (_despawnState != 2)
        SetDespawnTime(DespawnTime);

    me->GetMotionMaster()->MoveIdle();

    GetScript()->ProcessEventsFor(SMART_EVENT_WAYPOINT_STOPPED, nullptr, _currentWaypointNodeId, GetScript()->GetPathId());

    EndPath(fail);
}

void SmartAI::EndPath(bool fail)
{
    RemoveEscortState(SMART_ESCORT_ESCORTING | SMART_ESCORT_PAUSED | SMART_ESCORT_RETURNING);

    _waypointPauseTimer = 0;

    if (_escortNPCFlags)
    {
        me->ReplaceAllNpcFlags((NPCFlags)_escortNPCFlags);
        _escortNPCFlags = 0;
    }

    ObjectVector const* targets = GetScript()->GetStoredTargetVector(SMART_ESCORT_TARGETS, *me);
    if (targets && _escortQuestId)
    {
        if (targets->size() == 1 && targets->front()->IsPlayer())
        {
            Player* player = targets->front()->ToPlayer();
            if (!fail && player->IsAtGroupRewardDistance(me) && !player->HasCorpse())
                player->GroupEventHappens(_escortQuestId, me);

            if (fail)
                player->FailQuest(_escortQuestId);

            if (Group* group = player->GetGroup())
            {
                for (GroupReference const& groupRef : group->GetMembers())
                {
                    Player* groupGuy = groupRef.GetSource();
                    if (!groupGuy->IsInMap(player))
                        continue;

                    if (!fail && groupGuy->IsAtGroupRewardDistance(me) && !groupGuy->HasCorpse())
                        groupGuy->AreaExploredOrEventHappens(_escortQuestId);
                    else if (fail)
                        groupGuy->FailQuest(_escortQuestId);
                }
            }
        }
        else
        {
            for (WorldObject* target : *targets)
            {
                if (Player* player = target->ToPlayer())
                {
                    if (!fail && player->IsAtGroupRewardDistance(me) && !player->HasCorpse())
                        player->AreaExploredOrEventHappens(_escortQuestId);
                    else if (fail)
                        player->FailQuest(_escortQuestId);
                }
            }
        }
    }

    // End Path events should be only processed if it was SUCCESSFUL stop or stop called by SMART_ACTION_WAYPOINT_STOP
    if (fail)
        return;

    uint32 pathid = GetScript()->GetPathId();
    GetScript()->ProcessEventsFor(SMART_EVENT_WAYPOINT_ENDED, nullptr, _currentWaypointNodeId, pathid);

    if (_repeatWaypointPath)
    {
        if (IsAIControlled())
            StartPath(GetScript()->GetPathId(), _repeatWaypointPath);
    }
    else if (pathid == GetScript()->GetPathId()) // if it's not the same pathid, our script wants to start another path; don't override it
        GetScript()->SetPathId(0);

    if (_despawnState == 1)
        StartDespawn();
}

void SmartAI::ResumePath()
{
    GetScript()->ProcessEventsFor(SMART_EVENT_WAYPOINT_RESUMED, nullptr, _currentWaypointNodeId, GetScript()->GetPathId());

    RemoveEscortState(SMART_ESCORT_PAUSED);

    _waypointPauseForced = false;
    _waypointReached = false;
    _waypointPauseTimer = 0;

    SetRun(_run);
    me->ResumeMovement();
}

void SmartAI::ReturnToLastOOCPos()
{
    if (!IsAIControlled())
        return;

    me->SetWalk(false);
    me->GetMotionMaster()->MovePoint(SMART_ESCORT_LAST_OOC_POINT, me->GetHomePosition());
}

void SmartAI::UpdateAI(uint32 diff)
{
    if (!me->IsAlive())
    {
        if (IsEngaged())
            EngagementOver();
        return;
    }

    CheckConditions(diff);

    UpdateVictim();

    GetScript()->OnUpdate(diff);

    UpdatePath(diff);
    UpdateFollow(diff);
    UpdateDespawn(diff);
}

bool SmartAI::IsEscortInvokerInRange()
{
    if (ObjectVector const* targets = GetScript()->GetStoredTargetVector(SMART_ESCORT_TARGETS, *me))
    {
        float checkDist = me->GetInstanceScript() ? SMART_ESCORT_MAX_PLAYER_DIST * 2 : SMART_ESCORT_MAX_PLAYER_DIST;
        if (targets->size() == 1 && targets->front()->IsPlayer())
        {
            Player* player = targets->front()->ToPlayer();
            if (me->GetDistance(player) <= checkDist)
                return true;

            if (Group* group = player->GetGroup())
            {
                for (GroupReference const& groupRef : group->GetMembers())
                {
                    Player* groupGuy = groupRef.GetSource();
                    if (groupGuy->IsInMap(player) && me->GetDistance(groupGuy) <= checkDist)
                        return true;
                }
            }
        }
        else
        {
            for (WorldObject* target : *targets)
                if (target->IsPlayer() && me->GetDistance(target) <= checkDist)
                    return true;
        }

        // no valid target found
        return false;
    }

    // no player invoker was stored, just ignore range check
    return true;
}

void SmartAI::WaypointReached(uint32 nodeId, uint32 pathId)
{
    if (!HasEscortState(SMART_ESCORT_ESCORTING))
    {
        GetScript()->ProcessEventsFor(SMART_EVENT_WAYPOINT_REACHED, nullptr, nodeId, pathId);
        return;
    }

    _currentWaypointNodeId = nodeId;

    GetScript()->ProcessEventsFor(SMART_EVENT_WAYPOINT_REACHED, nullptr, _currentWaypointNodeId, pathId);

    if (_waypointPauseTimer && !_waypointPauseForced)
    {
        _waypointReached = true;
        me->PauseMovement();
        me->SetHomePosition(me->GetPosition());
    }
    else if (HasEscortState(SMART_ESCORT_ESCORTING) && me->GetMotionMaster()->GetCurrentMovementGeneratorType() == WAYPOINT_MOTION_TYPE)
    {
        WaypointPath const* path = sWaypointMgr->GetPath(pathId);
        if (path && _currentWaypointNodeId == path->Nodes.back().Id)
            _waypointPathEnded = true;
        else
            SetRun(_run);
    }
}

///@todo move escort related logic
void SmartAI::WaypointPathEnded(uint32 nodeId, uint32 pathId)
{
    if (!HasEscortState(SMART_ESCORT_ESCORTING))
    {
        GetScript()->ProcessEventsFor(SMART_EVENT_WAYPOINT_ENDED, nullptr, nodeId, pathId);
        return;
    }
}

void SmartAI::MovementInform(uint32 type, uint32 id)
{
    if (type == POINT_MOTION_TYPE && id == SMART_ESCORT_LAST_OOC_POINT)
        me->ClearUnitState(UNIT_STATE_EVADE);

    GetScript()->ProcessEventsFor(SMART_EVENT_MOVEMENTINFORM, nullptr, type, id);

    if (!HasEscortState(SMART_ESCORT_ESCORTING))
        return;

    if (type == POINT_MOTION_TYPE && id == SMART_ESCORT_LAST_OOC_POINT)
        _OOCReached = true;
}

void SmartAI::EnterEvadeMode(EvadeReason /*why*/)
{
    if (_evadeDisabled)
    {
        GetScript()->ProcessEventsFor(SMART_EVENT_EVADE);
        return;
    }

    if (!IsAIControlled())
    {
        me->AttackStop();
        return;
    }

    if (!_EnterEvadeMode())
        return;

    me->AddUnitState(UNIT_STATE_EVADE);

    GetScript()->ProcessEventsFor(SMART_EVENT_EVADE); // must be after _EnterEvadeMode (spells, auras, ...)

    SetRun(_run);

    if (Unit* owner = me->GetCharmerOrOwner())
    {
        me->GetMotionMaster()->MoveFollow(owner, PET_FOLLOW_DIST, PET_FOLLOW_ANGLE);
        me->ClearUnitState(UNIT_STATE_EVADE);
    }
    else if (HasEscortState(SMART_ESCORT_ESCORTING))
    {
        AddEscortState(SMART_ESCORT_RETURNING);
        ReturnToLastOOCPos();
    }
    else if (Unit* target = !_followGUID.IsEmpty() ? ObjectAccessor::GetUnit(*me, _followGUID) : nullptr)
    {
        me->GetMotionMaster()->MoveFollow(target, _followDistance, _followAngle);
        // evade is not cleared in MoveFollow, so we can't keep it
        me->ClearUnitState(UNIT_STATE_EVADE);
    }
    else
        me->GetMotionMaster()->MoveTargetedHome();

    if (!me->HasUnitState(UNIT_STATE_EVADE))
        GetScript()->OnReset();
}

void SmartAI::MoveInLineOfSight(Unit* who)
{
    if (!who)
        return;

    GetScript()->OnMoveInLineOfSight(who);

    if (!IsAIControlled())
        return;

    if (HasEscortState(SMART_ESCORT_ESCORTING) && AssistPlayerInCombatAgainst(who))
        return;

    CreatureAI::MoveInLineOfSight(who);
}

bool SmartAI::AssistPlayerInCombatAgainst(Unit* who)
{
    if (me->HasReactState(REACT_PASSIVE) || !IsAIControlled())
        return false;

    if (!who || !who->GetVictim())
        return false;

    // experimental (unknown) flag not present
    if (!(me->GetCreatureDifficulty()->TypeFlags & CREATURE_TYPE_FLAG_CAN_ASSIST))
        return false;

    // not a player
    if (!who->EnsureVictim()->GetCharmerOrOwnerPlayerOrPlayerItself())
        return false;

    if (!who->isInAccessiblePlaceFor(me))
        return false;

    if (!CanAIAttack(who))
        return false;

    // we cannot attack in evade mode
    if (me->IsInEvadeMode())
        return false;

    // or if enemy is in evade mode
    if (who->GetTypeId() == TYPEID_UNIT && who->ToCreature()->IsInEvadeMode())
        return false;

    if (!me->IsValidAssistTarget(who->GetVictim()))
        return false;

    // too far away and no free sight
    if (me->IsWithinDistInMap(who, SMART_MAX_AID_DIST) && me->IsWithinLOSInMap(who))
    {
        me->EngageWithTarget(who);
        return true;
    }

    return false;
}

void SmartAI::InitializeAI()
{
    GetScript()->OnInitialize(me);

    _despawnTime = 0;
    _despawnState = 0;
    _escortState = SMART_ESCORT_NONE;
    _followGUID.Clear(); // do not reset follower on Reset(), we need it after combat evade
    _followDistance = 0;
    _followAngle = 0;
    _followCredit = 0;
    _followArrivedTimer = 1000;
    _followArrivedEntry = 0;
    _followCreditType = 0;
}

void SmartAI::JustAppeared()
{
    CreatureAI::JustAppeared();

    if (me->isDead())
        return;

    GetScript()->ProcessEventsFor(SMART_EVENT_RESPAWN);
    GetScript()->OnReset();
}

void SmartAI::JustReachedHome()
{
    GetScript()->OnReset();
    GetScript()->ProcessEventsFor(SMART_EVENT_REACHED_HOME);

    CreatureGroup* formation = me->GetFormation();
    if (!formation || formation->GetLeader() == me || !formation->IsFormed())
    {
        if (me->GetMotionMaster()->GetCurrentMovementGeneratorType(MOTION_SLOT_DEFAULT) != WAYPOINT_MOTION_TYPE)
        {
            if (me->GetWaypointPathId())
                me->GetMotionMaster()->MovePath(me->GetWaypointPathId(), true);
        }

        me->ResumeMovement();
    }
    else if (formation->IsFormed())
        me->GetMotionMaster()->MoveIdle(); // wait the order of leader
}

void SmartAI::JustEngagedWith(Unit* enemy)
{
    if (IsAIControlled())
        me->InterruptNonMeleeSpells(false); // must be before ProcessEvents

    GetScript()->ProcessEventsFor(SMART_EVENT_AGGRO, enemy);
}

void SmartAI::JustDied(Unit* killer)
{
    if (HasEscortState(SMART_ESCORT_ESCORTING))
        EndPath(true);

    GetScript()->ProcessEventsFor(SMART_EVENT_DEATH, killer);
}

void SmartAI::KilledUnit(Unit* victim)
{
    GetScript()->ProcessEventsFor(SMART_EVENT_KILL, victim);
}

void SmartAI::JustSummoned(Creature* creature)
{
    GetScript()->ProcessEventsFor(SMART_EVENT_SUMMONED_UNIT, creature);
}

void SmartAI::SummonedCreatureDies(Creature* summon, Unit* /*killer*/)
{
    GetScript()->ProcessEventsFor(SMART_EVENT_SUMMONED_UNIT_DIES, summon);
}

void SmartAI::AttackStart(Unit* who)
{
    // dont allow charmed npcs to act on their own
    if (!IsAIControlled())
    {
        if (who)
            me->Attack(who, true);
        return;
    }

    if (who && me->Attack(who, true))
    {
        me->GetMotionMaster()->Clear(MOTION_PRIORITY_NORMAL);
        me->PauseMovement();

        if (_canCombatMove)
        {
            SetRun(_run);
            me->StartDefaultCombatMovement(who);
        }
    }
}

void SmartAI::SpellHit(WorldObject* caster, SpellInfo const* spellInfo)
{
    GetScript()->ProcessEventsFor(SMART_EVENT_SPELLHIT, caster->ToUnit(), 0, 0, false, spellInfo, caster->ToGameObject());
}

void SmartAI::SpellHitTarget(WorldObject* target, SpellInfo const* spellInfo)
{
    GetScript()->ProcessEventsFor(SMART_EVENT_SPELLHIT_TARGET, target->ToUnit(), 0, 0, false, spellInfo, target->ToGameObject());
}

void SmartAI::OnSpellCast(SpellInfo const* spellInfo)
{
    GetScript()->ProcessEventsFor(SMART_EVENT_ON_SPELL_CAST, nullptr, 0, 0, false, spellInfo);
}

void SmartAI::OnSpellFailed(SpellInfo const* spellInfo)
{
    GetScript()->ProcessEventsFor(SMART_EVENT_ON_SPELL_FAILED, nullptr, 0, 0, false, spellInfo);
}

void SmartAI::OnSpellStart(SpellInfo const* spellInfo)
{
    GetScript()->ProcessEventsFor(SMART_EVENT_ON_SPELL_START, nullptr, 0, 0, false, spellInfo);
}

void SmartAI::DamageTaken(Unit* doneBy, uint32& damage, DamageEffectType /*damageType*/, SpellInfo const* /*spellInfo = nullptr*/)
{
    GetScript()->ProcessEventsFor(SMART_EVENT_DAMAGED, doneBy, damage);

    if (!IsAIControlled()) // don't allow players to use unkillable units
        return;

    if (_invincibilityHPLevel && (damage >= me->GetHealth() - _invincibilityHPLevel))
        damage = me->GetHealth() - _invincibilityHPLevel; // damage should not be nullified, because of player damage req.
}

void SmartAI::HealReceived(Unit* doneBy, uint32& addhealth)
{
    GetScript()->ProcessEventsFor(SMART_EVENT_RECEIVE_HEAL, doneBy, addhealth);
}

void SmartAI::ReceiveEmote(Player* player, uint32 textEmote)
{
    GetScript()->ProcessEventsFor(SMART_EVENT_RECEIVE_EMOTE, player, textEmote);
}

void SmartAI::IsSummonedBy(WorldObject* summoner)
{
    GetScript()->ProcessEventsFor(SMART_EVENT_JUST_SUMMONED, summoner->ToUnit(), 0, 0, false, nullptr, summoner->ToGameObject());
}

void SmartAI::DamageDealt(Unit* doneTo, uint32& damage, DamageEffectType /*damagetype*/)
{
    GetScript()->ProcessEventsFor(SMART_EVENT_DAMAGED_TARGET, doneTo, damage);
}

void SmartAI::SummonedCreatureDespawn(Creature* unit)
{
    GetScript()->ProcessEventsFor(SMART_EVENT_SUMMON_DESPAWNED, unit, unit->GetEntry());
}

void SmartAI::CorpseRemoved(uint32& respawnDelay)
{
    GetScript()->ProcessEventsFor(SMART_EVENT_CORPSE_REMOVED, nullptr, respawnDelay);
}

void SmartAI::OnDespawn()
{
    GetScript()->ProcessEventsFor(SMART_EVENT_ON_DESPAWN);
}

void SmartAI::PassengerBoarded(Unit* who, int8 seatId, bool apply)
{
    GetScript()->ProcessEventsFor(apply ? SMART_EVENT_PASSENGER_BOARDED : SMART_EVENT_PASSENGER_REMOVED, who, uint32(seatId), 0, apply);
}

void SmartAI::OnCharmed(bool isNew)
{
    bool const charmed = me->IsCharmed();
    if (charmed) // do this before we change charmed state, as charmed state might prevent these things from processing
    {
        if (HasEscortState(SMART_ESCORT_ESCORTING | SMART_ESCORT_PAUSED | SMART_ESCORT_RETURNING))
            EndPath(true);
    }

    _charmed = charmed;

    if (charmed && !me->isPossessed() && !me->IsVehicle())
        me->GetMotionMaster()->MoveFollow(me->GetCharmer(), PET_FOLLOW_DIST, me->GetFollowAngle());

    if (!charmed && !me->IsInEvadeMode())
    {
        if (_repeatWaypointPath)
            StartPath(GetScript()->GetPathId(), true);
        else
            me->SetWalk(!_run);

        if (!me->LastCharmerGUID.IsEmpty())
        {
            if (!me->HasReactState(REACT_PASSIVE))
                if (Unit* lastCharmer = ObjectAccessor::GetUnit(*me, me->LastCharmerGUID))
                    me->EngageWithTarget(lastCharmer);
            me->LastCharmerGUID.Clear();

            if (!me->IsInCombat())
                EnterEvadeMode(EvadeReason::NoHostiles);
        }
    }

    GetScript()->ProcessEventsFor(SMART_EVENT_CHARMED, nullptr, 0, 0, charmed);

    if (!GetScript()->HasAnyEventWithFlag(SMART_EVENT_FLAG_WHILE_CHARMED)) // we can change AI if there are no events with this flag
        UnitAI::OnCharmed(isNew);
}

void SmartAI::DoAction(int32 param)
{
    GetScript()->ProcessEventsFor(SMART_EVENT_ACTION_DONE, nullptr, param);
}

uint32 SmartAI::GetData(uint32 /*id*/) const
{
    return 0;
}

void SmartAI::SetData(uint32 id, uint32 value, Unit* invoker)
{
    GetScript()->ProcessEventsFor(SMART_EVENT_DATA_SET, invoker, id, value);
}

void SmartAI::SetGUID(ObjectGuid const& /*guid*/, int32 /*id*/) { }

ObjectGuid SmartAI::GetGUID(int32 /*id*/) const
{
    return ObjectGuid::Empty;
}

void SmartAI::SetRun(bool run)
{
    me->SetWalk(!run);
    _run = run;
}

void SmartAI::SetEvadeDisabled(bool disable)
{
    _evadeDisabled = disable;
}

bool SmartAI::OnGossipHello(Player* player)
{
    _gossipReturn = false;
    GetScript()->ProcessEventsFor(SMART_EVENT_GOSSIP_HELLO, player);
    return _gossipReturn;
}

bool SmartAI::OnGossipSelect(Player* player, uint32 menuId, uint32 gossipListId)
{
    _gossipReturn = false;
    GetScript()->ProcessEventsFor(SMART_EVENT_GOSSIP_SELECT, player, menuId, gossipListId);
    return _gossipReturn;
}

bool SmartAI::OnGossipSelectCode(Player* /*player*/, uint32 /*menuId*/, uint32 /*gossipListId*/, char const* /*code*/)
{
    return false;
}

void SmartAI::OnQuestAccept(Player* player, Quest const* quest)
{
    GetScript()->ProcessEventsFor(SMART_EVENT_ACCEPTED_QUEST, player, quest->GetQuestId());
}

void SmartAI::OnQuestReward(Player* player, Quest const* quest, LootItemType /*type*/, uint32 opt)
{
    GetScript()->ProcessEventsFor(SMART_EVENT_REWARD_QUEST, player, quest->GetQuestId(), opt);
}

void SmartAI::SetCombatMove(bool on, bool stopMoving)
{
    if (_canCombatMove == on)
        return;

    _canCombatMove = on;

    if (!IsAIControlled())
        return;

    if (me->IsEngaged())
    {
        if (on)
        {
            if (!me->HasReactState(REACT_PASSIVE) && me->GetVictim() && !me->GetMotionMaster()->HasMovementGenerator([](MovementGenerator const* movement) -> bool
                {
                    return movement->GetMovementGeneratorType() == CHASE_MOTION_TYPE && movement->Mode == MOTION_MODE_DEFAULT && movement->Priority == MOTION_PRIORITY_NORMAL;
                }))
            {
                SetRun(_run);
                me->StartDefaultCombatMovement(me->GetVictim());
            }
        }
        else if (MovementGenerator* movement = me->GetMotionMaster()->GetMovementGenerator([](MovementGenerator const* a) -> bool
            {
                return a->GetMovementGeneratorType() == CHASE_MOTION_TYPE && a->Mode == MOTION_MODE_DEFAULT && a->Priority == MOTION_PRIORITY_NORMAL;
            }))
        {
            me->GetMotionMaster()->Remove(movement);
            if (stopMoving)
                me->StopMoving();
        }
    }
}

void SmartAI::SetFollow(Unit* target, float dist, float angle, uint32 credit, uint32 end, uint32 creditType)
{
    if (!target)
    {
        StopFollow(false);
        return;
    }

    _followGUID = target->GetGUID();
    _followDistance = dist;
    _followAngle = angle;
    _followArrivedTimer = 1000;
    _followCredit = credit;
    _followArrivedEntry = end;
    _followCreditType = creditType;
    SetRun(_run);
    me->GetMotionMaster()->MoveFollow(target, _followDistance, _followAngle);
}

void SmartAI::StopFollow(bool complete)
{
    _followGUID.Clear();
    _followDistance = 0;
    _followAngle = 0;
    uint32 followCredit = std::exchange(_followCredit, 0);
    _followArrivedTimer = 1000;
    _followArrivedEntry = 0;
    _followCreditType = 0;
    me->GetMotionMaster()->Clear();
    me->GetMotionMaster()->MoveIdle();

    if (!complete)
        return;

    Player* player = ObjectAccessor::GetPlayer(*me, _followGUID);
    if (player)
    {
        if (!_followCreditType)
            player->RewardPlayerAndGroupAtEvent(followCredit, me);
        else
            player->GroupEventHappens(followCredit, me);
    }

    SetDespawnTime(5000);
    StartDespawn();
    GetScript()->ProcessEventsFor(SMART_EVENT_FOLLOW_COMPLETED, player);
}

void SmartAI::SetTimedActionList(SmartScriptHolder& e, uint32 entry, Unit* invoker, uint32 startFromEventId)
{
    GetScript()->SetTimedActionList(e, entry, invoker, startFromEventId);
}

void SmartAI::OnGameEvent(bool start, uint16 eventId)
{
    GetScript()->ProcessEventsFor(start ? SMART_EVENT_GAME_EVENT_START : SMART_EVENT_GAME_EVENT_END, nullptr, eventId);
}

void SmartAI::OnSpellClick(Unit* clicker, bool spellClickHandled)
{
    if (!spellClickHandled)
        return;

    GetScript()->ProcessEventsFor(SMART_EVENT_ON_SPELLCLICK, clicker);
}

void SmartAI::CheckConditions(uint32 diff)
{
    if (!_vehicleConditions)
        return;

    if (_vehicleConditionsTimer <= diff)
    {
        if (Vehicle* vehicleKit = me->GetVehicleKit())
        {
            for (std::pair<int8 const, VehicleSeat>& seat : vehicleKit->Seats)
                if (Unit* passenger = ObjectAccessor::GetUnit(*me, seat.second.Passenger.Guid))
                {
                    if (Player* player = passenger->ToPlayer())
                    {
                        if (!sConditionMgr->IsObjectMeetingNotGroupedConditions(CONDITION_SOURCE_TYPE_CREATURE_TEMPLATE_VEHICLE, me->GetEntry(), player, me))
                        {
                            player->ExitVehicle();
                            return; // check other pessanger in next tick
                        }
                    }
                }
        }

        _vehicleConditionsTimer = 1000;
    }
    else
        _vehicleConditionsTimer -= diff;
}

void SmartAI::UpdatePath(uint32 diff)
{
    if (!HasEscortState(SMART_ESCORT_ESCORTING))
        return;

    if (_escortInvokerCheckTimer < diff)
    {
        if (!IsEscortInvokerInRange())
        {
            StopPath(0, _escortQuestId, true);

            // allow to properly hook out of range despawn action, which in most cases should perform the same operation as dying
            GetScript()->ProcessEventsFor(SMART_EVENT_DEATH, me);
            me->DespawnOrUnsummon();
            return;
        }
        _escortInvokerCheckTimer = 1000;
    }
    else
        _escortInvokerCheckTimer -= diff;

    // handle pause
    if (HasEscortState(SMART_ESCORT_PAUSED) && (_waypointReached || _waypointPauseForced))
    {
        // Resume only if there was a pause timer set
        if (_waypointPauseTimer && !me->IsInCombat() && !HasEscortState(SMART_ESCORT_RETURNING))
        {
            if (_waypointPauseTimer <= diff)
                ResumePath();
            else
                _waypointPauseTimer -= diff;
        }
    }
    else if (_waypointPathEnded) // end path
    {
        _waypointPathEnded = false;
        StopPath();
        return;
    }

    if (HasEscortState(SMART_ESCORT_RETURNING))
    {
        if (_OOCReached) // reached OOC WP
        {
            _OOCReached = false;
            RemoveEscortState(SMART_ESCORT_RETURNING);
            if (!HasEscortState(SMART_ESCORT_PAUSED))
                ResumePath();
        }
    }
}

void SmartAI::UpdateFollow(uint32 diff)
{
    if (!_followGUID.IsEmpty())
    {
        if (_followArrivedTimer < diff)
        {
            if (me->FindNearestCreature(_followArrivedEntry, INTERACTION_DISTANCE, true))
            {
                StopFollow(true);
                return;
            }

            _followArrivedTimer = 1000;
        }
        else
            _followArrivedTimer -= diff;
    }
}

void SmartAI::UpdateDespawn(uint32 diff)
{
    if (_despawnState <= 1 || _despawnState > 3)
        return;

    if (_despawnTime < diff)
    {
        if (_despawnState == 2)
        {
            me->SetVisible(false);
            _despawnTime = 5000;
            _despawnState++;
        }
        else
            me->DespawnOrUnsummon();
    }
    else
        _despawnTime -= diff;
}

void SmartGameObjectAI::UpdateAI(uint32 diff)
{
    GetScript()->OnUpdate(diff);
}

void SmartGameObjectAI::InitializeAI()
{
    GetScript()->OnInitialize(me);
    // do not call respawn event if go is not spawned
    if (me->isSpawned())
        GetScript()->ProcessEventsFor(SMART_EVENT_RESPAWN);
    //Reset();
}

void SmartGameObjectAI::Reset()
{
    GetScript()->OnReset();
}

// Called when a player opens a gossip dialog with the gameobject.
bool SmartGameObjectAI::OnGossipHello(Player* player)
{
    _gossipReturn = false;
    GetScript()->ProcessEventsFor(SMART_EVENT_GOSSIP_HELLO, player, 0, 0, false, nullptr, me);
    return _gossipReturn;
}

// Called when a player selects a gossip item in the gameobject's gossip menu.
bool SmartGameObjectAI::OnGossipSelect(Player* player, uint32 sender, uint32 action)
{
    _gossipReturn = false;
    GetScript()->ProcessEventsFor(SMART_EVENT_GOSSIP_SELECT, player, sender, action, false, nullptr, me);
    return _gossipReturn;
}

// Called when a player selects a gossip with a code in the gameobject's gossip menu.
bool SmartGameObjectAI::OnGossipSelectCode(Player* /*player*/, uint32 /*menuId*/, uint32 /*gossipListId*/, char const* /*code*/)
{
    return false;
}

// Called when a player accepts a quest from the gameobject.
void SmartGameObjectAI::OnQuestAccept(Player* player, Quest const* quest)
{
    GetScript()->ProcessEventsFor(SMART_EVENT_ACCEPTED_QUEST, player, quest->GetQuestId(), 0, false, nullptr, me);
}

// Called when a player selects a quest reward.
void SmartGameObjectAI::OnQuestReward(Player* player, Quest const* quest, LootItemType /*type*/, uint32 opt)
{
    GetScript()->ProcessEventsFor(SMART_EVENT_REWARD_QUEST, player, quest->GetQuestId(), opt, false, nullptr, me);
}

bool SmartGameObjectAI::OnReportUse(Player* player)
{
    _gossipReturn = false;
    GetScript()->ProcessEventsFor(SMART_EVENT_GOSSIP_HELLO, player, 1, 0, false, nullptr, me);
    return _gossipReturn;
}

// Called when the gameobject is destroyed (destructible buildings only).
void SmartGameObjectAI::Destroyed(WorldObject* attacker, uint32 eventId)
{
    GetScript()->ProcessEventsFor(SMART_EVENT_DEATH, attacker ? attacker->ToUnit() : nullptr, eventId, 0, false, nullptr, me);
}

void SmartGameObjectAI::SetData(uint32 id, uint32 value, Unit* invoker)
{
    GetScript()->ProcessEventsFor(SMART_EVENT_DATA_SET, invoker, id, value);
}

void SmartGameObjectAI::SetTimedActionList(SmartScriptHolder& e, uint32 entry, Unit* invoker)
{
    GetScript()->SetTimedActionList(e, entry, invoker);
}

void SmartGameObjectAI::OnGameEvent(bool start, uint16 eventId)
{
    GetScript()->ProcessEventsFor(start ? SMART_EVENT_GAME_EVENT_START : SMART_EVENT_GAME_EVENT_END, nullptr, eventId);
}

void SmartGameObjectAI::OnLootStateChanged(uint32 state, Unit* unit)
{
    GetScript()->ProcessEventsFor(SMART_EVENT_GO_LOOT_STATE_CHANGED, unit, state);
}

void SmartGameObjectAI::EventInform(uint32 eventId)
{
    GetScript()->ProcessEventsFor(SMART_EVENT_GO_EVENT_INFORM, nullptr, eventId);
}

void SmartGameObjectAI::SpellHit(WorldObject* caster, SpellInfo const* spellInfo)
{
    GetScript()->ProcessEventsFor(SMART_EVENT_SPELLHIT, caster->ToUnit(), 0, 0, false, spellInfo);
}

void SmartGameObjectAI::JustSummoned(Creature* creature)
{
    GetScript()->ProcessEventsFor(SMART_EVENT_SUMMONED_UNIT, creature);
}

void SmartGameObjectAI::SummonedCreatureDies(Creature* summon, Unit* /*killer*/)
{
    GetScript()->ProcessEventsFor(SMART_EVENT_SUMMONED_UNIT_DIES, summon);
}

void SmartGameObjectAI::SummonedCreatureDespawn(Creature* unit)
{
    GetScript()->ProcessEventsFor(SMART_EVENT_SUMMON_DESPAWNED, unit, unit->GetEntry());
}

class SmartTrigger : public AreaTriggerScript
{
    public:

        SmartTrigger() : AreaTriggerScript("SmartTrigger") { }

        bool OnTrigger(Player* player, AreaTriggerEntry const* trigger) override
        {
            TC_LOG_DEBUG("scripts.ai", "AreaTrigger {} enter is using SmartTrigger script", trigger->ID);
            SmartScript script;
            script.OnInitialize(player, trigger);
            script.ProcessEventsFor(SMART_EVENT_AREATRIGGER_ENTER, player);
            return true;
        }

        bool OnExit(Player* player, AreaTriggerEntry const* trigger) override
        {
            TC_LOG_DEBUG("scripts.ai", "AreaTrigger {} exit is using SmartTrigger script", trigger->ID);
            SmartScript script;
            script.OnInitialize(player, trigger);
            script.ProcessEventsFor(SMART_EVENT_AREATRIGGER_EXIT, player);
            return true;
        }
};

void SmartAreaTriggerAI::OnInitialize()
{
    GetScript()->OnInitialize(at);
}

void SmartAreaTriggerAI::OnUpdate(uint32 diff)
{
    GetScript()->OnUpdate(diff);
}

void SmartAreaTriggerAI::OnUnitEnter(Unit* unit)
{
    GetScript()->ProcessEventsFor(SMART_EVENT_AREATRIGGER_ENTER, unit);
}

void SmartAreaTriggerAI::OnUnitExit(Unit* unit, AreaTriggerExitReason /*reason*/)
{
    GetScript()->ProcessEventsFor(SMART_EVENT_AREATRIGGER_EXIT, unit);
}

void SmartAreaTriggerAI::SetTimedActionList(SmartScriptHolder& e, uint32 entry, Unit* invoker)
{
    GetScript()->SetTimedActionList(e, entry, invoker);
}

class SmartAreaTriggerEntityScript : public AreaTriggerEntityScript
{
public:
    SmartAreaTriggerEntityScript() : AreaTriggerEntityScript("SmartAreaTriggerAI")
    {
    }

    AreaTriggerAI* GetAI(AreaTrigger* areaTrigger) const override
    {
        return new SmartAreaTriggerAI(areaTrigger);
    }
};

class SmartScene : public SceneScript
{
public:
    SmartScene() : SceneScript("SmartScene") { }

    void OnSceneStart(Player* player, uint32 /*sceneInstanceID*/, SceneTemplate const* sceneTemplate) override
    {
        SmartScript smartScript;
        smartScript.OnInitialize(player, nullptr, sceneTemplate);
        smartScript.ProcessEventsFor(SMART_EVENT_SCENE_START, player);
    }

    void OnSceneTriggerEvent(Player* player, uint32 /*sceneInstanceID*/, SceneTemplate const* sceneTemplate, std::string const& triggerName) override
    {
        SmartScript smartScript;
        smartScript.OnInitialize(player, nullptr, sceneTemplate);
        smartScript.ProcessEventsFor(SMART_EVENT_SCENE_TRIGGER, player, 0, 0, false, nullptr, nullptr, triggerName);
    }

    void OnSceneCancel(Player* player, uint32 /*sceneInstanceID*/, SceneTemplate const* sceneTemplate) override
    {
        SmartScript smartScript;
        smartScript.OnInitialize(player, nullptr, sceneTemplate);
        smartScript.ProcessEventsFor(SMART_EVENT_SCENE_CANCEL, player);
    }

    void OnSceneComplete(Player* player, uint32 /*sceneInstanceID*/, SceneTemplate const* sceneTemplate) override
    {
        SmartScript smartScript;
        smartScript.OnInitialize(player, nullptr, sceneTemplate);
        smartScript.ProcessEventsFor(SMART_EVENT_SCENE_COMPLETE, player);
    }
};

class SmartQuest : public QuestScript
{
public:
    SmartQuest() : QuestScript("SmartQuest") { }

    // Called when a quest status change
    void OnQuestStatusChange(Player* player, Quest const* quest, QuestStatus /*oldStatus*/, QuestStatus newStatus) override
    {
        SmartScript smartScript;
        smartScript.OnInitialize(player, nullptr, nullptr, quest);
        switch (newStatus)
        {
            case QUEST_STATUS_INCOMPLETE:
                smartScript.ProcessEventsFor(SMART_EVENT_QUEST_ACCEPTED, player);
                break;
            case QUEST_STATUS_COMPLETE:
                smartScript.ProcessEventsFor(SMART_EVENT_QUEST_COMPLETION, player);
                break;
            case QUEST_STATUS_FAILED:
                smartScript.ProcessEventsFor(SMART_EVENT_QUEST_FAIL, player);
                break;
            case QUEST_STATUS_REWARDED:
                smartScript.ProcessEventsFor(SMART_EVENT_QUEST_REWARDED, player);
                break;
            case QUEST_STATUS_NONE:
            default:
                break;
        }
    }

    // Called when a quest objective data change
    void OnQuestObjectiveChange(Player* player, Quest const* quest, QuestObjective const& objective, int32 /*oldAmount*/, int32 /*newAmount*/) override
    {
        uint16 slot = player->FindQuestSlot(quest->GetQuestId());
        if (slot < MAX_QUEST_LOG_SIZE && player->IsQuestObjectiveComplete(slot, quest, objective))
        {
            SmartScript smartScript;
            smartScript.OnInitialize(player, nullptr, nullptr, quest);
            smartScript.ProcessEventsFor(SMART_EVENT_QUEST_OBJ_COMPLETION, player, objective.ID);
        }
    }
};

class SmartEventTrigger : public EventScript
{
public:
    SmartEventTrigger() : EventScript("SmartEventTrigger") { }

    void OnTrigger(WorldObject* object, WorldObject* invoker, uint32 eventId) override
    {
        TC_LOG_DEBUG("scripts.ai", "Event {} is using SmartEventTrigger script", eventId);
        SmartScript script;
        // Set invoker as BaseObject if there isn't target for GameEvents::Trigger
        script.OnInitialize(Coalesce<WorldObject>(object, invoker), nullptr, nullptr, nullptr, eventId);
        script.ProcessEventsFor(SMART_EVENT_SEND_EVENT_TRIGGER, invoker->ToUnit(), 0, 0, false, nullptr, invoker->ToGameObject());
    }
};

void AddSC_SmartScripts()
{
    new SmartTrigger();
    new SmartAreaTriggerEntityScript();
    new SmartScene();
    new SmartQuest();
    new SmartEventTrigger();
}