/*
 * Copyright (C) 2005-2009 MaNGOS <http://getmangos.com/>
 *
 * Copyright (C) 2008-2010 Trinity <http://www.trinitycore.org/>
 *
 * 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, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */

#include "Creature.h"
#include "MapManager.h"
#include "Opcodes.h"
#include "ConfusedMovementGenerator.h"
#include "DestinationHolderImp.h"
#include "VMapFactory.h"

#ifdef MAP_BASED_RAND_GEN
#define rand_norm() unit.rand_norm()
#define urand(a,b) unit.urand(a,b)
#endif

template<class T>
void
ConfusedMovementGenerator<T>::Initialize(T &unit)
{
    const float wander_distance = 11;
    float x,y,z;
    x = unit.GetPositionX();
    y = unit.GetPositionY();
    z = unit.GetPositionZ();

    Map const* map = unit.GetBaseMap();

    i_nextMove = 1;

    bool is_water_ok, is_land_ok;
    _InitSpecific(unit, is_water_ok, is_land_ok);

    VMAP::IVMapManager *vMaps = VMAP::VMapFactory::createOrGetVMapManager();

    for (uint8 idx = 0; idx <= MAX_CONF_WAYPOINTS; ++idx)
    {
        const bool isInLoS = vMaps->isInLineOfSight(unit.GetMapId(), x, y, z + 2.0f, i_waypoints[idx][0], i_waypoints[idx][1], z + 2.0f);
        if (isInLoS)
        {
            const float wanderX = wander_distance*rand_norm() - wander_distance/2;
            const float wanderY = wander_distance*rand_norm() - wander_distance/2;
            i_waypoints[idx][0] = x + wanderX;
            i_waypoints[idx][1] = y + wanderY;
        }
        else
        {
            i_waypoints[idx][0] = x;
            i_waypoints[idx][1] = y;
        }

        // prevent invalid coordinates generation
        Trinity::NormalizeMapCoord(i_waypoints[idx][0]);
        Trinity::NormalizeMapCoord(i_waypoints[idx][1]);

        bool is_water = map->IsInWater(i_waypoints[idx][0],i_waypoints[idx][1],z);
        // if generated wrong path just ignore
        if ((is_water && !is_water_ok) || (!is_water && !is_land_ok))
        {
            i_waypoints[idx][0] = idx > 0 ? i_waypoints[idx-1][0] : x;
            i_waypoints[idx][1] = idx > 0 ? i_waypoints[idx-1][1] : y;
        }

        unit.UpdateGroundPositionZ(i_waypoints[idx][0],i_waypoints[idx][1],z);
        i_waypoints[idx][2] = z;
    }

    unit.SetUInt64Value(UNIT_FIELD_TARGET, 0);
    unit.SetFlag(UNIT_FIELD_FLAGS, UNIT_FLAG_CONFUSED);
    unit.CastStop();
    unit.StopMoving();
    unit.RemoveUnitMovementFlag(MOVEMENTFLAG_WALK_MODE);
    unit.addUnitState(UNIT_STAT_CONFUSED);
}

template<>
void
ConfusedMovementGenerator<Creature>::_InitSpecific(Creature &creature, bool &is_water_ok, bool &is_land_ok)
{
    is_water_ok = creature.canSwim();
    is_land_ok  = creature.canWalk();
}

template<>
void
ConfusedMovementGenerator<Player>::_InitSpecific(Player &, bool &is_water_ok, bool &is_land_ok)
{
    is_water_ok = true;
    is_land_ok  = true;
}

template<class T>
void
ConfusedMovementGenerator<T>::Reset(T &unit)
{
    i_nextMove = 1;
    i_nextMoveTime.Reset(0);
    i_destinationHolder.ResetUpdate();
    unit.StopMoving();
}

template<class T>
bool
ConfusedMovementGenerator<T>::Update(T &unit, const uint32 &diff)
{
    if (!&unit)
        return true;

    if (unit.hasUnitState(UNIT_STAT_ROOT | UNIT_STAT_STUNNED | UNIT_STAT_DISTRACTED))
        return true;

    if (i_nextMoveTime.Passed())
    {
        // currently moving, update location
        Traveller<T> traveller(unit);
        if (i_destinationHolder.UpdateTraveller(traveller, diff))
        {
            if (i_destinationHolder.HasArrived())
            {
                // arrived, stop and wait a bit
                unit.clearUnitState(UNIT_STAT_MOVE);

                i_nextMove = urand(1,MAX_CONF_WAYPOINTS);
                i_nextMoveTime.Reset(urand(0, 1500-1));     // TODO: check the minimum reset time, should be probably higher
            }
        }
    }
    else
    {
        // waiting for next move
        i_nextMoveTime.Update(diff);
        if (i_nextMoveTime.Passed())
        {
            // start moving
            assert(i_nextMove <= MAX_CONF_WAYPOINTS);
            const float x = i_waypoints[i_nextMove][0];
            const float y = i_waypoints[i_nextMove][1];
            const float z = i_waypoints[i_nextMove][2];
            Traveller<T> traveller(unit);
            i_destinationHolder.SetDestination(traveller, x, y, z);
        }
    }
    return true;
}

template<class T>
void
ConfusedMovementGenerator<T>::Finalize(T &unit)
{
    unit.RemoveFlag(UNIT_FIELD_FLAGS, UNIT_FLAG_CONFUSED);
    unit.clearUnitState(UNIT_STAT_CONFUSED);
    if (unit.GetTypeId() == TYPEID_UNIT && unit.getVictim())
        unit.SetUInt64Value(UNIT_FIELD_TARGET, unit.getVictim()->GetGUID());
}

template void ConfusedMovementGenerator<Player>::Initialize(Player &player);
template void ConfusedMovementGenerator<Creature>::Initialize(Creature &creature);
template void ConfusedMovementGenerator<Player>::Finalize(Player &player);
template void ConfusedMovementGenerator<Creature>::Finalize(Creature &creature);
template void ConfusedMovementGenerator<Player>::Reset(Player &player);
template void ConfusedMovementGenerator<Creature>::Reset(Creature &creature);
template bool ConfusedMovementGenerator<Player>::Update(Player &player, const uint32 &diff);
template bool ConfusedMovementGenerator<Creature>::Update(Creature &creature, const uint32 &diff);