canDoCombat

ReturnValue Combat::canDoCombat(const Creature* attacker, const Creature* target)
{
    if(attacker){
        if(const Player* targetPlayer = target->getPlayer()){
            if(targetPlayer->hasFlag(PlayerFlag_CannotBeAttacked)){
                return RET_YOUMAYNOTATTACKTHISPERSON;
            }

            if(const Player* attackerPlayer = attacker->getPlayer()){
                if(attackerPlayer->hasFlag(PlayerFlag_CannotAttackPlayer) ||
                    attackerPlayer->isLoginAttackLocked(targetPlayer->getID())){
                    return RET_YOUMAYNOTATTACKTHISPERSON;
                }
            }

            if(const Player* masterAttackerPlayer = attacker->getPlayerMaster()){
                if(masterAttackerPlayer->hasFlag(PlayerFlag_CannotAttackPlayer)){
                    return RET_YOUMAYNOTATTACKTHISPERSON;
                }
            }
        }
        else if(target->getMonster()){
            if(const Player* attackerPlayer = attacker->getPlayer()){
                if(attackerPlayer->hasFlag(PlayerFlag_CannotAttackMonster)){
                    return RET_YOUMAYNOTATTACKTHISCREATURE;
                }
            } else if (attacker->getMonster()) {
                const Creature* targetMaster = target->getMaster();

                if (!targetMaster || !targetMaster->getPlayer()) {
                    const Creature* attackerMaster = attacker->getMaster();

                    if (!attackerMaster || !attackerMaster->getPlayer()) {
                        return RET_YOUMAYNOTATTACKTHISCREATURE;
                    }
                }
            }
        }
        if(attacker->getPlayer() || attacker->isPlayerSummon()){
            //nopvp-zone
            if(target->getPlayer() && target->getTile()->hasFlag(TILESTATE_NOPVPZONE)){
                return RET_ACTIONNOTPERMITTEDINANONPVPZONE;
            }

            return Combat::checkPVPExtraRestrictions(attacker, target, false);
        }
    }

    return RET_NOERROR;
}