/*
    * Copyright (C) 2020-2023 Dipl.-Inform. Kai Hofmann. All rights reserved!
    */
   package de.powerstat.validation.values;
   
   
   import java.util.Objects;
   import java.util.regex.Pattern;
   
  import de.powerstat.validation.interfaces.IValueObject;
  
  
  /**
   * Address Building number.
   *
   * Possibly DSGVO relevant.
   *
   * TODO optimize constructor/compareTo
   */
  public final class BuildingNr implements Comparable<BuildingNr>, IValueObject
   {
    /* *
     * Logger.
     */
    // private static final Logger LOGGER = LogManager.getLogger(BuildingNr.class);
  
    /* *
     * Cache for singletons.
     */
    // private static final Map<String, BuildingNr> CACHE = new WeakHashMap<>();
  
    /**
     * Building nr regexp.
     */
    private static final Pattern BUILDINGNR_REGEXP = Pattern.compile("^(\\d{1,5})(([-/])(\\d{1,5}))?( (\\d{1,3})/(\\d{1,3}))?( ([a-z]))?$"); //$NON-NLS-1$
  
    /**
     * Maximum known building nr in the world.
     */
    private static final int MAX_KNOWN_BUILDING_NR = 29999;
  
    /**
     * Building number.
     */
    private final String buildingNr;
  
  
    /**
     * Constructor.
     *
     * @param buildingNr Building number
     * @throws NullPointerException if buildingNr is null
     * @throws IllegalArgumentException if buildingNr is not an correct buildingNr
     */
    private BuildingNr(final String buildingNr)
     {
      super();
      Objects.requireNonNull(buildingNr, "buildingNr"); //$NON-NLS-1$
      if ((buildingNr.length() < 1) || (buildingNr.length() > 21))
       {
        throw new IllegalArgumentException("BuildingNr with wrong length"); //$NON-NLS-1$
       }
      final var matcher = BuildingNr.BUILDINGNR_REGEXP.matcher(buildingNr);
      if (!matcher.matches())
       {
        throw new IllegalArgumentException("BuildingNr with wrong format"); //$NON-NLS-1$
       }
      // group 1: building nr (from) 42:   42
      // group 4: building nr (to) 42-43:  43
      // group 6: numerator 3/4:         3
      // group 7: denominator 3/4:       4
      // group 8: alphabetic character:  a
      if (Integer.parseInt(matcher.group(1)) > BuildingNr.MAX_KNOWN_BUILDING_NR)
       {
        throw new IllegalArgumentException("BuildingNr > " + BuildingNr.MAX_KNOWN_BUILDING_NR); //$NON-NLS-1$
       }
      if ((matcher.group(4) != null) && (Integer.compare(Integer.parseInt(matcher.group(1)), Integer.parseInt(matcher.group(4))) >= 0))
       {
        throw new IllegalArgumentException("BuildingNr from >= BuildingNr to"); //$NON-NLS-1$
       }
      if ((matcher.group(7) != null) && (Integer.compare(Integer.parseInt(matcher.group(6)), Integer.parseInt(matcher.group(7))) > 0))
       {
        throw new IllegalArgumentException("BuildingNr numerator > denominator"); //$NON-NLS-1$
       }
      this.buildingNr = buildingNr;
     }
  
  
    /**
     * BuildingNr factory.
     *
     * @param buildingNr Building number
     * @return BuildingNr object
     */
    public static BuildingNr of(final String buildingNr)
     {
      /*
      synchronized (BuildingNr.class)
       {
       BuildingNr obj = BuildingNr.CACHE.get(buildingNr);
       if (obj != null)
        {
         return obj;
        }
       obj = new BuildingNr(buildingNr);
       BuildingNr.CACHE.put(buildingNr, obj);
       return obj;
      }
     */
     return new BuildingNr(buildingNr);
    }
 
 
   /**
    * Returns the value of this BuildingNr as a string.
    *
    * @return The text value represented by this object after conversion to type string.
    */
   @Override
   public String stringValue()
    {
     return this.buildingNr;
    }
 
 
   /**
    * Calculate hash code.
    *
    * @return Hash
    * @see java.lang.Object#hashCode()
    */
   @Override
   public int hashCode()
    {
     return this.buildingNr.hashCode();
    }
 
 
   /**
    * 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 BuildingNr))
      {
       return false;
      }
     final BuildingNr other = (BuildingNr)obj;
     return this.buildingNr.equals(other.buildingNr);
    }
 
 
   /**
    * Returns the string representation of this BuildingNr.
    *
    * The exact details of this representation are unspecified and subject to change, but the following may be regarded as typical:
    *
    * "BuildingNr[buildingNr=42]"
    *
    * @return String representation of this BuildingNr
    * @see java.lang.Object#toString()
    */
   @Override
   public String toString()
    {
     final var builder = new StringBuilder(23);
     builder.append("BuildingNr[buildingNr=").append(this.buildingNr).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)
    *
    * TODO optimize (do regexp in constructor)
    */
   @Override
   public int compareTo(final BuildingNr obj)
    {
     Objects.requireNonNull(obj, "obj"); //$NON-NLS-1$
     final var matcher1 = BuildingNr.BUILDINGNR_REGEXP.matcher(this.buildingNr);
     final var matcher2 = BuildingNr.BUILDINGNR_REGEXP.matcher(obj.buildingNr);
     /* boolean result1 = */ matcher1.matches();
     /* boolean result2 = */ matcher2.matches();
     // group 1: building nr (from) 42:   42
     // group 4: building nr (to) 42-43:  43
     // group 6: numerator 3/4:         3
     // group 7: denominator 3/4:       4
     // group 8: alphabetic character:  a
     int result = Integer.compare(Integer.parseInt(matcher1.group(1)), Integer.parseInt(matcher2.group(1)));
     if (result == 0)
      {
       if ((matcher1.group(7) != null) || (matcher2.group(7) != null)) // 3/4
        {
         if (matcher1.group(7) == null)
          {
           return -1;
          }
         if (matcher2.group(7) == null)
          {
           return 1;
          }
         if (matcher1.group(7).compareTo(matcher2.group(7)) != 0)
          {
           throw new IllegalStateException("BuildingNrs do not have the same denominator"); //$NON-NLS-1$
          }
         result = Integer.compare(Integer.parseInt(matcher1.group(6)), Integer.parseInt(matcher2.group(6)));
         if (result != 0)
          {
           return result;
          }
        }
       if ((matcher1.group(8) != null) || (matcher2.group(8) != null)) // a-z
        {
         if (matcher1.group(8) == null)
          {
           result = -1;
          }
         else if (matcher2.group(8) == null)
          {
           result = 1;
          }
         else
          {
           result = matcher1.group(8).compareTo(matcher2.group(8));
          }
        }
      }
     return result;
    }
 
  }