pushattackaction.java

MegaMek is a networked Java clone of BattleTech, a turn-based sci-fi boardgame for 2+ players. Fight

/*
 * MegaMek - Copyright (C) 2000,2001,2002,2003,2004 Ben Mazur ([e-mail])
 * 
 *  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.
 */

package megamek.common.actions;

import megamek.common.*;

/**
 * The attacker pushes the target.
 */
public class PushAttackAction
    extends DisplacementAttackAction
{
    public PushAttackAction(int entityId, int targetId, Coords targetPos) {
        super(entityId, targetId, targetPos);
    }

    public PushAttackAction(int entityId, int targetType, int targetId, Coords targetPos) {
        super(entityId, targetType, targetId, targetPos);
    }
    
    public ToHitData toHit(IGame game) {
        return toHit(game, getEntityId(),
                game.getTarget(getTargetType(), getTargetId()));
    }


    /**
     * To-hit number for the mech to push another mech
     */
    public static ToHitData toHit(IGame game,
                                      int attackerId,
                                      Targetable target) {
        final Entity ae = game.getEntity(attackerId);
        int targetId = Entity.NONE;
        Entity te = null;
        if ( target.getTargetType() == Targetable.TYPE_ENTITY ) {
            te = (Entity) target;
            targetId = target.getTargetId();
        }
        if (ae == null)
            return new ToHitData(ToHitData.IMPOSSIBLE, "You can't attack from a null entity!");
        if (te == null)
            return new ToHitData(ToHitData.IMPOSSIBLE, "You can't target a null entity!");
        IHex attHex = game.getBoard().getHex(ae.getPosition());
        IHex targHex = game.getBoard().getHex(te.getPosition());
        final int attackerElevation = ae.getElevation() + attHex.getElevation();
        final int targetElevation = target.getElevation() + targHex.getElevation();
        final boolean targetInBuilding = Compute.isInBuilding( game, te );
        Building bldg = null;
        if ( targetInBuilding ) {
            bldg = game.getBoard().getBuildingAt( te.getPosition() );
        }
        ToHitData toHit = null;

        // arguments legal?
        if (ae == null || target == null) {
            throw new IllegalArgumentException("Attacker or target not valid");
        }

        // can't target yourself
        if (ae.equals(te)) {
            return new ToHitData(ToHitData.IMPOSSIBLE, "You can't target yourself");
        }

        // non-mechs can't push
        if (!(ae instanceof Mech)) {
            return new ToHitData(ToHitData.IMPOSSIBLE, "Non-mechs can't push");
        }

        //Quads can't push
        if ( ae.entityIsQuad() ) {
            return new ToHitData(ToHitData.IMPOSSIBLE, "Attacker is a quad");
        }

        // can't make physical attacks while spotting
        if (ae.isSpotting()) {
            return new ToHitData(ToHitData.IMPOSSIBLE, "Attacker is spotting this turn");
        }

        //Can only push mechs
        if ( te !=null && !(te instanceof Mech) ) {
            return new ToHitData(ToHitData.IMPOSSIBLE, "Target is not a mech");
        }

        //Can't push with flipped arms
        if (ae.getArmsFlipped()) {
            return new ToHitData(ToHitData.IMPOSSIBLE, "Arms are flipped to the rear. Can not push.");
        }

        // Can't target a transported entity.
        if ( te != null && Entity.NONE != te.getTransportId() ) {
            return new ToHitData(ToHitData.IMPOSSIBLE, "Target is a passenger.");
        }

        // Can't target a entity conducting a swarm attack.
        if ( te != null && Entity.NONE != te.getSwarmTargetId() ) {
            return new ToHitData(ToHitData.IMPOSSIBLE, "Target is swarming a Mek.");
        }

        // check if both arms are present
        if (ae.isLocationBad(Mech.LOC_RARM)
            || ae.isLocationBad(Mech.LOC_LARM)) {
            return new ToHitData(ToHitData.IMPOSSIBLE, "Arm missing");
        }

        // check if attacker has fired arm-mounted weapons
        if (ae.weaponFiredFrom(Mech.LOC_RARM)
        || ae.weaponFiredFrom(Mech.LOC_LARM)) {
            return new ToHitData(ToHitData.IMPOSSIBLE, "Weapons fired from arm this turn");
        }

        // check range
        if (ae.getPosition().distance(target.getPosition()) > 1 ) {
            return new ToHitData(ToHitData.IMPOSSIBLE, "Target not in range");
        }

        // target must be at same elevation
        if (attackerElevation != targetElevation) {
            return new ToHitData(ToHitData.IMPOSSIBLE, "Target not at same elevation");
        }

        // can't push mech making non-pushing displacement attack
        if ( te != null && te.hasDisplacementAttack() && !te.isPushing() ) {
            return new ToHitData(ToHitData.IMPOSSIBLE, "Target is making a charge/DFA attack");
        }

        // can't push mech pushing another, different mech
        if ( te != null && te.isPushing() &&
             te.getDisplacementAttack().getTargetId() != ae.getId() ) {
            return new ToHitData(ToHitData.IMPOSSIBLE, "Target is pushing another mech");
        }

        // can't do anything but counter-push if the target of another attack
        if (ae.isTargetOfDisplacementAttack() && ae.findTargetedDisplacement().getEntityId() != target.getTargetId()) {
            return new ToHitData(ToHitData.IMPOSSIBLE, "Attacker is the target of another push/charge/DFA");
        }

        // can't attack the target of another displacement attack
        if ( te != null && te.isTargetOfDisplacementAttack() &&
             te.findTargetedDisplacement().getEntityId() != ae.getId() ) {
            return new ToHitData(ToHitData.IMPOSSIBLE, "Target is the target of another push/charge/DFA");
        }

        // check facing
        if (!target.getPosition().equals(ae.getPosition().translated(ae.getFacing()))) {
            return new ToHitData(ToHitData.IMPOSSIBLE, "Target not directly ahead of feet");
        }

        // can't push while prone
        if (ae.isProne()) {
            return new ToHitData(ToHitData.IMPOSSIBLE, "Attacker is prone");
        }

        // can't push prone mechs
        if ( te != null && te.isProne()) {
            return new ToHitData(ToHitData.IMPOSSIBLE, "Target is prone");
        }

        // Can't target units in buildings (from the outside).
        if ( targetInBuilding ) {
            if ( !Compute.isInBuilding(game, ae) ) {
                return new ToHitData(ToHitData.IMPOSSIBLE, "Target is inside building" );
            }
            else if ( !game.getBoard().getBuildingAt( ae.getPosition() )
                      .equals( bldg ) ) {
                return new ToHitData(ToHitData.IMPOSSIBLE, "Target is inside differnt building" );
            }
        }

        // Attacks against adjacent buildings automatically hit.
        if ((target.getTargetType() == Targetable.TYPE_BUILDING)
                || (target.getTargetType() == Targetable.TYPE_FUEL_TANK)) {
            return new ToHitData(ToHitData.IMPOSSIBLE,
                    "You can not push a building (well, you can, but it won't do anything).");
        }

        // Can't target woods or ignite a building with a physical.
        if ( target.getTargetType() == Targetable.TYPE_BLDG_IGNITE ||
             target.getTargetType() == Targetable.TYPE_HEX_CLEAR ||
             target.getTargetType() == Targetable.TYPE_HEX_IGNITE ) {
            return new ToHitData( ToHitData.IMPOSSIBLE, "Invalid attack");
        }

        //Set the base BTH
          int base = 4;

          if ( game.getOptions().booleanOption("maxtech_physical_BTH") ) {
            base = ae.getCrew().getPiloting() - 1;
          }

          toHit = new ToHitData(base, "base");

        // attacker movement
        toHit.append(Compute.getAttackerMovementModifier(game, attackerId));

        // target movement
        toHit.append(Compute.getTargetMovementModifier(game, targetId));

        // attacker terrain
        toHit.append(Compute.getAttackerTerrainModifier(game, attackerId));

        // target terrain
        toHit.append(Compute.getTargetTerrainModifier(game, te));

        // damaged or missing actuators
        if (!ae.hasWorkingSystem(Mech.ACTUATOR_SHOULDER, Mech.LOC_RARM)) {
            toHit.addModifier(2, "Right Shoulder destroyed");
        }
        if (!ae.hasWorkingSystem(Mech.ACTUATOR_SHOULDER, Mech.LOC_LARM)) {
            toHit.addModifier(2, "Left Shoulder destroyed");
        }

        // water partial cover?
        if (te.height() > 0
                && te.getElevation() == -1
                && targHex.terrainLevel(Terrains.WATER) == te.height()) {
            toHit.addModifier(3, "target has partial cover");
        }

        // target immobile
        toHit.append(Compute.getImmobileMod(te));

        Compute.modifyPhysicalBTHForAdvantages(ae, te, toHit, game);

        toHit.append(nightModifiers(game, target, null, ae));
        // side and elevation shouldn't matter
        
        // If it has a torso-mounted cockpit and two head sensor hits or three sensor hits...
        // It gets a =4 penalty for being blind!
        if (((Mech)ae).getCockpitType() == Mech.COCKPIT_TORSO_MOUNTED) {
            int sensorHits = ae.getBadCriticals(CriticalSlot.TYPE_SYSTEM, Mech.SYSTEM_SENSORS, Mech.LOC_HEAD);
            int sensorHits2 = ae.getBadCriticals(CriticalSlot.TYPE_SYSTEM, Mech.SYSTEM_SENSORS, Mech.LOC_CT);
            if ((sensorHits + sensorHits2) == 3) {
                return new ToHitData(ToHitData.IMPOSSIBLE, "Sensors Completely Destroyed for Torso-Mounted Cockpit");
            } else if (sensorHits == 2) {
                toHit.addModifier(4, "Head Sensors Destroyed for Torso-Mounted Cockpit");
            }
        }

        // done!
        return toHit;
    }
}