/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License, Version 1.0 only
 * (the "License").  You may not use this file except in compliance
 * with the License.
 *
 * You can obtain a copy of the license at
 * trunk/opends/resource/legal-notices/OpenDS.LICENSE
 * or https://OpenDS.dev.java.net/OpenDS.LICENSE.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at
 * trunk/opends/resource/legal-notices/OpenDS.LICENSE.  If applicable,
 * add the following below this CDDL HEADER, with the fields enclosed
 * by brackets "[]" replaced with your own identifying information:
 *      Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 *
 *
 *      Copyright 2009 Sun Microsystems, Inc.
 */

package org.opends.sdk.schema;



import static com.sun.opends.sdk.messages.Messages.ERR_ATTR_SYNTAX_TELEPHONE_EMPTY;
import static com.sun.opends.sdk.messages.Messages.ERR_ATTR_SYNTAX_TELEPHONE_ILLEGAL_CHAR;
import static com.sun.opends.sdk.messages.Messages.ERR_ATTR_SYNTAX_TELEPHONE_NO_DIGITS;
import static com.sun.opends.sdk.messages.Messages.ERR_ATTR_SYNTAX_TELEPHONE_NO_PLUS;
import static com.sun.opends.sdk.util.StaticUtils.isDigit;
import static org.opends.sdk.schema.SchemaConstants.EMR_TELEPHONE_OID;
import static org.opends.sdk.schema.SchemaConstants.SMR_TELEPHONE_OID;
import static org.opends.sdk.schema.SchemaConstants.SYNTAX_TELEPHONE_NAME;

import org.opends.sdk.ByteSequence;
import org.opends.sdk.LocalizableMessage;
import org.opends.sdk.LocalizableMessageBuilder;



/**
 * This class implements the telephone number attribute syntax, which is defined
 * in RFC 2252. Note that this can have two modes of operation, depending on its
 * configuration. Most of the time, it will be very lenient when deciding what
 * to accept, and will allow anything but only pay attention to the digits.
 * However, it can also be configured in a "strict" mode, in which case it will
 * only accept values in the E.123 international telephone number format.
 */
final class TelephoneNumberSyntaxImpl extends AbstractSyntaxImpl
{

  @Override
  public String getEqualityMatchingRule()
  {
    return EMR_TELEPHONE_OID;
  }



  public String getName()
  {
    return SYNTAX_TELEPHONE_NAME;
  }



  @Override
  public String getSubstringMatchingRule()
  {
    return SMR_TELEPHONE_OID;
  }



  public boolean isHumanReadable()
  {
    return false;
  }



  /**
   * Indicates whether the provided value is acceptable for use in an attribute
   * with this syntax. If it is not, then the reason may be appended to the
   * provided buffer.
   *
   * @param schema
   *          The schema in which this syntax is defined.
   * @param value
   *          The value for which to make the determination.
   * @param invalidReason
   *          The buffer to which the invalid reason should be appended.
   * @return <CODE>true</CODE> if the provided value is acceptable for use with
   *         this syntax, or <CODE>false</CODE> if not.
   */
  public boolean valueIsAcceptable(final Schema schema,
      final ByteSequence value, final LocalizableMessageBuilder invalidReason)
  {
    // No matter what, the value can't be empty or null.
    String valueStr;
    if (value == null || (valueStr = value.toString().trim()).length() == 0)
    {
      invalidReason.append(ERR_ATTR_SYNTAX_TELEPHONE_EMPTY.get());
      return false;
    }

    final int length = valueStr.length();

    if (schema.getSchemaCompatOptions().isTelephoneNumberSyntaxStrict())
    {
      // If the value does not start with a plus sign, then that's not
      // acceptable.
      if (valueStr.charAt(0) != '+')
      {
        final LocalizableMessage message = ERR_ATTR_SYNTAX_TELEPHONE_NO_PLUS
            .get(valueStr);
        invalidReason.append(message);
        return false;
      }

      // Iterate through the remaining characters in the value. There
      // must be at least one digit, and it must contain only valid
      // digits and separator characters.
      boolean digitSeen = false;
      for (int i = 1; i < length; i++)
      {
        final char c = valueStr.charAt(i);
        if (isDigit(c))
        {
          digitSeen = true;
        }
        else if (!isSeparator(c))
        {
          final LocalizableMessage message = ERR_ATTR_SYNTAX_TELEPHONE_ILLEGAL_CHAR
              .get(valueStr, String.valueOf(c), i);
          invalidReason.append(message);
          return false;
        }
      }

      if (!digitSeen)
      {
        final LocalizableMessage message = ERR_ATTR_SYNTAX_TELEPHONE_NO_DIGITS
            .get(valueStr);
        invalidReason.append(message);
        return false;
      }

      // If we've gotten here, then we'll consider it acceptable.
      return true;
    }
    else
    {
      // If we are not in strict mode, then all non-empty values
      // containing at least one digit will be acceptable.
      for (int i = 0; i < length; i++)
      {
        if (isDigit(valueStr.charAt(i)))
        {
          return true;
        }
      }

      // If we made it here, then we didn't find any digits.
      final LocalizableMessage message = ERR_ATTR_SYNTAX_TELEPHONE_NO_DIGITS
          .get(valueStr);
      invalidReason.append(message);
      return false;
    }
  }



  /**
   * Indicates whether the provided character is a valid separator for telephone
   * number components when operating in strict mode.
   *
   * @param c
   *          The character for which to make the determination.
   * @return <CODE>true</CODE> if the provided character is a valid separator,
   *         or <CODE>false</CODE> if it is not.
   */
  private boolean isSeparator(final char c)
  {
    switch (c)
    {
    case ' ':
    case '-':
      return true;
    default:
      return false;
    }
  }
}