/*
    *  Licensed to the Apache Software Foundation (ASF) under one
    *  or more contributor license agreements.  See the NOTICE file
    *  distributed with this work for additional information
    *  regarding copyright ownership.  The ASF licenses this file
    *  to you under the Apache License, Version 2.0 (the
    *  "License"); you may not use this file except in compliance
    *  with the License.  You may obtain a copy of the License at
    *  
   *    http://www.apache.org/licenses/LICENSE-2.0
   *  
   *  Unless required by applicable law or agreed to in writing,
   *  software distributed under the License is distributed on an
   *  "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
   *  KIND, either express or implied.  See the License for the
   *  specific language governing permissions and limitations
   *  under the License. 
   *  
   */
  package org.apache.directory.api.ldap.model.schema.syntaxCheckers;
  
  
  import java.util.regex.Pattern;
  import java.util.regex.PatternSyntaxException;
  
  import org.apache.directory.api.i18n.I18n;
  import org.apache.directory.api.ldap.model.constants.SchemaConstants;
  import org.apache.directory.api.ldap.model.schema.SyntaxChecker;
  import org.apache.directory.api.util.Strings;
  
  
  /**
   * A SyntaxChecker which verifies that a value is a TelephoneNumber according to ITU
   * recommendation E.123 (which is quite vague ...).
   * <p>
   * A valid Telephone number respects more or less this syntax :
   * 
   * <pre>
   * " *[+]? *((\([0-9- ,;/#*]+\))|[0-9- ,;/#*]+)+"
   * </pre>
   * 
   * If needed, and to allow more syntaxes, a list of regexps has been added
   * which can be initialized to other values
   * 
   * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a>
   */
  @SuppressWarnings("serial")
  public final class TelephoneNumberSyntaxChecker extends SyntaxChecker
  {
      /** The default pattern used to check a TelephoneNumber */
      private static final String DEFAULT_REGEXP = "^ *[+]? *((\\([0-9- ,;/#*]+\\))|[0-9- ,;/#*]+)+$";
      
      /** The default pattern */
      private final String defaultRegexp;
  
      /** The compiled default pattern */
      private final Pattern defaultPattern;
  
      /**
       * A static instance of TelephoneNumberSyntaxChecker
       */
      public static final TelephoneNumberSyntaxChecker INSTANCE = 
          new TelephoneNumberSyntaxChecker( SchemaConstants.TELEPHONE_NUMBER_SYNTAX );
      
      /**
       * A static Builder for this class
       */
      public static final class Builder extends SCBuilder<TelephoneNumberSyntaxChecker>
      {
          /** The default pattern */
          private String defaultRegexp;
  
          /** The compiled default pattern */
          private Pattern defaultPattern;
  
          /**
           * The Builder constructor
           */
          private Builder()
          {
              super( SchemaConstants.TELEPHONE_NUMBER_SYNTAX );
              setDefaultRegexp( DEFAULT_REGEXP );
          }
          
          
          /**
           * Create a new instance of TelephoneNumberSyntaxChecker
           * @return A new instance of TelephoneNumberSyntaxChecker
           */
          @Override
          public TelephoneNumberSyntaxChecker build()
          {
              return new TelephoneNumberSyntaxChecker( oid, defaultRegexp, defaultPattern );
          }
  
  
          /**
           * Set the default regular expression for the Telephone number
           * 
          * @param regexp the default regular expression.
          */
         public Builder setDefaultRegexp( String regexp )
         {
             defaultRegexp = regexp;
             
             try
             {
                 defaultPattern = Pattern.compile( regexp );
             }
             catch ( PatternSyntaxException pse )
             {
                 // Roll back to the default pattern
                 defaultPattern = Pattern.compile( DEFAULT_REGEXP );
             }
 
             return this;
         }
     }
 
     
     /**
      * Creates a new instance of a child of this class, with an OID.
      * 
      * @param oid the child's OID
      */
     private TelephoneNumberSyntaxChecker( String oid )
     {
         this( oid, DEFAULT_REGEXP, Pattern.compile( DEFAULT_REGEXP ) );
     }
 
     
     /**
      * Creates a new instance of a child of this class, with an OID.
      * 
      * @param oid the child's OID
      * @param defaultRegexp The regexp to use
      * @param defaultPattern The compiled version of the regexp
      */
     private TelephoneNumberSyntaxChecker( String oid, String defaultRegexp, Pattern defaultPattern )
     {
         super( oid );
 
         this.defaultPattern = defaultPattern;
         this.defaultRegexp = defaultRegexp;
     }
 
     
     /**
      * @return An instance of the Builder for this class
      */
     public static Builder builder()
     {
         return new Builder();
     }
 
 
     /**
      * Get the default regexp (either the original one, or the one that has been set)
      * 
      * @return The default regexp
      */
     public String getRegexp()
     {
         return defaultRegexp;
     }
 
 
     /**
      * {@inheritDoc}
      */
     @Override
     public boolean isValidSyntax( Object value )
     {
         String strValue;
 
         if ( value == null )
         {
             if ( LOG.isDebugEnabled() )
             {
                 LOG.debug( I18n.err( I18n.ERR_04488_SYNTAX_INVALID, "null" ) );
             }
             
             return false;
         }
 
         if ( value instanceof String )
         {
             strValue = ( String ) value;
         }
         else if ( value instanceof byte[] )
         {
             strValue = Strings.utf8ToString( ( byte[] ) value );
         }
         else
         {
             strValue = value.toString();
         }
 
         if ( strValue.length() == 0 )
         {
             if ( LOG.isDebugEnabled() )
             {
                 LOG.debug( I18n.err( I18n.ERR_04488_SYNTAX_INVALID, value ) );
             }
             
             return false;
         }
 
         // We will use a regexp to check the TelephoneNumber.
         boolean result;
         
         // Not sure this is 100% necessary...
         synchronized ( defaultPattern )
         {
             result = defaultPattern.matcher( strValue ).matches();
         }
 
         if ( LOG.isDebugEnabled() )
         {
             if ( result )
             {
                 LOG.debug( I18n.msg( I18n.MSG_04489_SYNTAX_VALID, value ) );
             }
             else
             {
                 LOG.debug( I18n.err( I18n.ERR_04488_SYNTAX_INVALID, value ) );
             }
         }
 
         return result;
     }
 }