/*
    * Copyright (C) 2020-2023 Dipl.-Inform. Kai Hofmann. All rights reserved!
    */
   package de.powerstat.validation.values;
   
   
   import java.util.Objects;
   
   import de.powerstat.validation.interfaces.IValueObject;
  
  
  /**
   * Months.
   *
   * Not DSGVO relevant.
   *
   * TODO min, max
   */
  public final class Months implements Comparable<Months>, IValueObject
   {
    /* *
     * Cache for singletons.
     */
    // private static final Map<Long, Months> CACHE = new WeakHashMap<>();
  
    /**
     * Month.
     */
    private final long months;
  
  
    /**
     * Constructor.
     *
     * @param months Months 0-..
     * @throws IndexOutOfBoundsException When the months is less than 0
     */
    private Months(final long months)
     {
      super();
      if (months < 0)
       {
        throw new IndexOutOfBoundsException("Negative months are not allowed"); //$NON-NLS-1$
       }
      this.months = months;
     }
  
  
    /**
     * Months factory.
     *
     * @param months Months 0-..
     * @return Months object
     */
    public static Months of(final long months)
     {
      /*
      synchronized (Months.class)
       {
        Months obj = Months.CACHE.get(months);
        if (obj != null)
         {
          return obj;
         }
        obj = new Months(months);
        Months.CACHE.put(Long.valueOf(months), obj);
        return obj;
       }
      */
      return new Months(months);
     }
  
  
    /**
     * Months factory.
     *
     * @param value Months 0-.. string
     * @return Months object
     */
    public static Months of(final String value)
     {
      return of(Long.parseLong(value));
     }
  
  
    /**
     * Returns the value of this Months as a long.
     *
     * @return The numeric value represented by this object after conversion to type long.
     */
    public long longValue()
     {
      return this.months;
     }
  
  
    /**
     * Returns the value of this Months as a String.
     *
    * @return The numeric value represented by this object after conversion to type String.
    */
   @Override
   public String stringValue()
    {
     return String.valueOf(this.months);
    }
 
 
   /**
    * Calculate hash code.
    *
    * @return Hash
    * @see java.lang.Object#hashCode()
    */
   @Override
   public int hashCode()
    {
     return Long.hashCode(this.months);
    }
 
 
   /**
    * Is equal with another object.
    *
    * @param obj Object
    * @return true when equal, false otherwise
    * @see java.lang.Object#equals(java.lang.Object)
    */
   @Override
   public boolean equals(final Object obj)
    {
     if (this == obj)
      {
       return true;
      }
     if (!(obj instanceof Months))
      {
       return false;
      }
     final Months other = (Months)obj;
     return this.months == other.months;
    }
 
 
   /**
    * Returns the string representation of this Months.
    *
    * The exact details of this representation are unspecified and subject to change, but the following may be regarded as typical:
    *
    * "Months[months=1]"
    *
    * @return String representation of this Months
    * @see java.lang.Object#toString()
    */
   @Override
   public String toString()
    {
     final var builder = new StringBuilder();
     builder.append("Months[months=").append(this.months).append(']'); //$NON-NLS-1$
     return builder.toString();
    }
 
 
   /**
    * Compare with another object.
    *
    * @param obj Object to compare with
    * @return 0: equal; 1: greater; -1: smaller
    * @see java.lang.Comparable#compareTo(java.lang.Object)
    */
   @Override
   public int compareTo(final Months obj)
    {
     Objects.requireNonNull(obj, "obj"); //$NON-NLS-1$
     return Long.compare(this.months, obj.months);
    }
 
 
   /**
    * Add other months to this months.
    *
    * @param other Other months to add to this months
    * @return New months after adding other months to this months
    * @throws ArithmeticException In case of an overflow
    */
   public Months add(final Months other)
    {
     return Months.of(Math.addExact(this.months, other.months));
    }
 
 
   /**
    * Subtract other months from this months.
    *
    * @param other Other months to subtract from this one
    * @return Absolute new months after subtracting other months from this months
    */
   public Months subtract(final Months other)
    {
     if (other.months > this.months)
      {
       return Months.of(other.months - this.months);
      }
     return Months.of(this.months - other.months);
    }
 
 
   /**
    * Multiply months with a multiplier.
    *
    * @param multiplier Multiplier to multiply with
    * @return New months that is a multiplication of this months with the multiplier
    * @throws ArithmeticException In case of an overflow
    */
   public Months multiply(final long multiplier)
    {
     return Months.of(Math.multiplyExact(this.months, multiplier));
    }
 
 
   /**
    * Divide months by a divisor.
    *
    * @param divisor Divisor to divide by
    * @return The largest (closest to positive infinity) long value that is less than or equal to the algebraic quotient.
    * @throws ArithmeticException In case the divisor is 0.
    */
   public Months divide(final long divisor)
    {
     return Months.of(Math.floorDiv(this.months, divisor));
    }
 
 
   /**
    * Floor modulo months by a divisor.
    *
    * @param divisor Divisor to divide by
    * @return The floor modulus Months - (floorDiv(Months, divisor) * divisor)
    * @throws ArithmeticException In case the divisor is 0.
    */
   public Months modulo(final long divisor)
    {
     return Months.of(Math.floorMod(this.months, divisor));
    }
 
  }