/*
    * (c) Copyright 2006-2020 by rapiddweller GmbH & Volker Bergmann. All rights reserved.
    *
    * Redistribution and use in source and binary forms, with or without
    * modification, is permitted under the terms of the
    * GNU General Public License.
    *
    * For redistributing this software or a derivative work under a license other
    * than the GPL-compatible Free Software License as defined by the Free
   * Software Foundation or approved by OSI, you must first obtain a commercial
   * license to this software product from rapiddweller GmbH & Volker Bergmann.
   *
   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
   * WITHOUT A WARRANTY OF ANY KIND. ALL EXPRESS OR IMPLIED CONDITIONS,
   * REPRESENTATIONS AND WARRANTIES, INCLUDING ANY IMPLIED WARRANTY OF
   * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT, ARE
   * HEREBY EXCLUDED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
   * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
   * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
   * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
   * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
   * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
   * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
   * POSSIBILITY OF SUCH DAMAGE.
   */
  
  package com.rapiddweller.benerator.distribution.sequence;
  
  import com.rapiddweller.benerator.Generator;
  import com.rapiddweller.benerator.InvalidGeneratorSetupException;
  import com.rapiddweller.benerator.NonNullGenerator;
  import com.rapiddweller.benerator.distribution.Sequence;
  import com.rapiddweller.benerator.distribution.SequenceManager;
  import com.rapiddweller.benerator.wrapper.SkipGeneratorProxy;
  import com.rapiddweller.benerator.wrapper.WrapperFactory;
  import com.rapiddweller.common.BeanUtil;
  import com.rapiddweller.common.NumberUtil;
  
  import java.math.BigDecimal;
  
  import static com.rapiddweller.common.NumberUtil.toDouble;
  import static com.rapiddweller.common.NumberUtil.toInteger;
  import static com.rapiddweller.common.NumberUtil.toLong;
  
  /**
   * Creates numbers by continuously incrementing a base value by a constant amount.<br/>
   * <br/>
   * Created at 30.06.2009 09:55:20
   *
   * @author Volker Bergmann
   * @since 0.6.0
   */
  public class StepSequence extends Sequence {
  
    private BigDecimal delta;
    private final BigDecimal initial;
    private final BigDecimal limit;
  
    /**
     * Instantiates a new Step sequence.
     */
    public StepSequence() {
      this(null); // when using null, the granularity parameter will be used to set the increment in createGenerator
    }
  
    /**
     * Instantiates a new Step sequence.
     *
     * @param delta the increment to choose for created generators.              When using null, the granularity parameter will be used to set the increment              in {@link #createNumberGenerator(Class, Number, Number, Number, boolean)}
     */
    public StepSequence(BigDecimal delta) {
      this(delta, null);
    }
  
    /**
     * Instantiates a new Step sequence.
     *
     * @param delta   the delta
     * @param initial the initial
     */
    public StepSequence(BigDecimal delta, BigDecimal initial) {
      this(delta, initial, null);
    }
  
    /**
     * Instantiates a new Step sequence.
     *
     * @param delta   the delta
     * @param initial the initial
     * @param limit   the limit
     */
    public StepSequence(BigDecimal delta, BigDecimal initial, BigDecimal limit) {
      this.delta = delta;
      this.initial = initial;
      this.limit = limit;
    }
  
    /**
     * Sets delta.
    *
    * @param delta the delta
    */
   public void setDelta(BigDecimal delta) {
     this.delta = delta;
   }
 
   /**
    * Gets delta.
    *
    * @return the delta
    */
   public BigDecimal getDelta() {
     return delta;
   }
 
   /**
    * Gets initial.
    *
    * @return the initial
    */
   public BigDecimal getInitial() {
     return initial;
   }
 
   @Override
   public <T> Generator<T> applyTo(Generator<T> source, boolean unique) {
     int deltaToUse = (delta != null ? toInteger(delta) : 1);
     if (delta != null && delta.longValue() < 0) {
       return super.applyTo(source, unique);
     } else {
       return new SkipGeneratorProxy<>(source, deltaToUse, deltaToUse,
           SequenceManager.RANDOM_SEQUENCE, toInteger(limit));
     }
   }
 
   @Override
   public <T extends Number> NonNullGenerator<T> createNumberGenerator(
       Class<T> numberType, T min, T max, T granularity, boolean unique) {
     Number deltaToUse = deltaToUse(granularity);
     if (unique && deltaToUse.doubleValue() == 0) {
       throw new InvalidGeneratorSetupException("Can't generate unique numbers with an increment of 0.");
     }
     NonNullGenerator<? extends Number> base;
     if (BeanUtil.isIntegralNumberType(numberType)) {
       if (max == null) {
         max = NumberUtil.maxValue(numberType);
       }
       base = new StepLongGenerator(
           toLong(min), toLong(max), toLong(deltaToUse), toLong(initial));
     } else {
       base = new StepDoubleGenerator(
           toDouble(min), toDouble(max), toDouble(deltaToUse), toDouble(initial));
     }
     return WrapperFactory.asNonNullNumberGeneratorOfType(numberType, base, min, granularity);
   }
 
   private <T extends Number> Number deltaToUse(T granularity) {
     return (delta != null ? delta : (granularity != null ? granularity : 1));
   }
 
   @Override
   public String toString() {
     return BeanUtil.toString(this);
   }
 
 }