/*
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    * must also contain a copy of this document.
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   * info@exolab.org.
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   * their names without prior written permission of Intalio, Inc. Exolab is a registered trademark of
   * Intalio, Inc.
   *
   * 5. Due credit should be given to the Exolab Project (http://www.exolab.org/).
   *
   * THIS SOFTWARE IS PROVIDED BY INTALIO, INC. AND CONTRIBUTORS ``AS IS'' AND ANY EXPRESSED OR
   * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
   * FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL INTALIO, INC. OR ITS
   * 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.
   *
   * Copyright 2000-2003 (C) Intalio, Inc. All Rights Reserved.
   *
   * $Id$ Date Author Changes 10/31/2000 Arnaud Blandin Created
   */
  package org.exolab.castor.xml.validators;
  
  import java.lang.reflect.InvocationTargetException;
  import java.lang.reflect.Method;
  import java.math.BigDecimal;
  
  import org.exolab.castor.xml.TypeValidator;
  import org.exolab.castor.xml.ValidationContext;
  import org.exolab.castor.xml.ValidationException;
  
  /**
   * The Decimal Validation class. This class handles validation for the <code>BigDecimal</code> type.
   *
   * @author <a href="mailto:blandin@intalio.com">Arnaud Blandin</a>
   * @author <a href="mailto:edward.kuns@aspect.com">Edward Kuns</a>
   * @version $Revision$ $Date: 2006-04-25 15:08:23 -0600 (Tue, 25 Apr 2006) $
   */
  public class DecimalValidator extends PatternValidator implements TypeValidator {
  
    /** Reference to the Method BigDecimal.toPlainString(), only in JDK 5 or later. */
    private static Method _bdMethodToPlainString = null;
  
    static {
      try {
        _bdMethodToPlainString = BigDecimal.class.getMethod("toPlainString", (Class[]) null);
      } catch (NoSuchMethodException e) {
        // If it does not exist, we're in Java 1.4.2 or earlier
      }
    }
  
    /** Fixed value of this short. (Not used if null.) */
    private BigDecimal _fixed = null;
    /** Minimum value (inclusive or exclusive) for this BigDecimal. (Not used if null.) */
    private BigDecimal _min = null;
    /** Maximum value (inclusive or exclusive) for this BigDecimal. (Not used if null.) */
    private BigDecimal _max = null;
    /** Maximum number of significant digits in this BigDecimal. (Not applied if < 0.) */
    private int _totalDigits = -1;
    /** Maximum number of fractional digits in this BigDecimal. (Not applied if < 0.) */
    private int _fractionDigits = -1;
    /** If true, the minimum value is an <b>exclusive</b> value. */
    private boolean _hasMinExclusive = false;
    /** If true, the maximum value is an <b>exclusive</b> value. */
    private boolean _hasMaxExclusive = false;
  
    /**
     * Creates a new DecimalValidator with no restrictions.
     */
    public DecimalValidator() {
      super();
    } // -- decimalValidator
  
    /**
     * Clears the fixed value for this BigIntegerValidator.
     */
    public void clearFixed() {
      _fixed = null;
    } // -- clearFixed
  
    /**
     * Clears the maximum value for this DecimalValidator.
     */
    public void clearMax() {
      _max = null;
      _hasMaxExclusive = false;
   } // -- clearMax
 
   /**
    * Clears the minimum value for this DecimalValidator.
    */
   public void clearMin() {
     _min = null;
     _hasMinExclusive = false;
   } // -- clearMin
 
   /**
    * Returns the configured fixed value for BigDecimal validation. Returns null if no fixed value
    * has been configured.
    *
    * @return the fixed value to validate against.
    */
   public BigDecimal getFixed() {
     return _fixed;
   } // -- getFixed
 
   /**
    * Returns the configured inclusive maximum value for BigDecimal validation. Returns null if no
    * inclusive maximum has been configured.
    *
    * @return the maximum inclusive value to validate against.
    */
   public BigDecimal getMaxInclusive() {
     return (_hasMaxExclusive) ? null : _max;
   } // -- getMaxInclusive
 
   /**
    * Returns the configured exclusive maximum value for BigDecimal validation. Returns null if no
    * exclusive maximum has been configured.
    *
    * @return the maximum exclusive value to validate against.
    */
   public BigDecimal getMaxExclusive() {
     return (_hasMaxExclusive) ? _max : null;
   } // -- getMaxInclusive
 
   /**
    * Returns the configured inclusive minimum value for BigDecimal validation. Returns null if no
    * inclusive minimum has been configured.
    *
    * @return the minimum inclusive value to validate against.
    */
   public BigDecimal getMinInclusive() {
     return (_hasMinExclusive) ? null : _min;
   } // -- getMinInclusive
 
   /**
    * Returns the configured exclusive minimum value for BigDecimal validation. Returns null if no
    * exclusive minimum has been configured.
    *
    * @return the minimum exclusive value to validate against.
    */
   public BigDecimal getMinExclusive() {
     return (_hasMinExclusive) ? _min : null;
   } // -- getMinInclusive
 
   /**
    * Returns true if a fixed value to validate against has been set.
    *
    * @return true if a fixed value has been set.
    */
   public boolean hasFixed() {
     return (_fixed != null);
   } // -- hasFixed
 
   /**
    * Sets the fixed value for BigDecimal validation.
    * <p>
    * NOTE: If maximum and/or minimum values have been set and the fixed value is not within that
    * max/min range, then no BigDecimal will pass validation. This is as according to the XML Schema
    * spec.
    *
    * @param fixedValue the fixed value that a BigDecimal validated with this validator must be equal
    *        to.
    */
   public void setFixed(final BigDecimal fixedValue) {
     _fixed = fixedValue;
   } // -- setMinExclusive
 
   /**
    * Sets the minimum (exclusive) value for BigDecimal validation. To pass validation, a BigDecimal
    * must be greater than this value.
    *
    * @param minValue the minimum (exclusive) value for BigDecimal validation.
    */
   public void setMinExclusive(final BigDecimal minValue) {
     if (minValue == null) {
       throw new IllegalArgumentException("argument 'minValue' must not be null.");
     }
     _min = minValue;
     _hasMinExclusive = true;
   } // -- setMinExclusive
 
   /**
    * Sets the minimum (inclusive) value for BigDecimal validation. To pass validation, a BigDecimal
    * must be greater than or equal to this value.
    *
    * @param minValue the minimum (inclusive) value for BigDecimal validation.
    */
   public void setMinInclusive(final BigDecimal minValue) {
     _min = minValue;
     _hasMinExclusive = false;
   } // -- setMinInclusive
 
   /**
    * Sets the maximum (exclusive) value for BigDecimal validation. To pass validation, a BigDecimal
    * must be less than this value.
    *
    * @param maxValue the maximum (exclusive) value for BigDecimal validation.
    */
   public void setMaxExclusive(final BigDecimal maxValue) {
     if (maxValue == null) {
       throw new IllegalArgumentException("argument 'maxValue' must not be null.");
     }
     _max = maxValue;
     _hasMaxExclusive = true;
   } // -- setMaxExclusive
 
   /**
    * Sets the maximum (inclusive) value for BigDecimal validation. To pass validation, a BigDecimal
    * must be less than or equal to this value.
    *
    * @param maxValue the maximum (inclusive) value for BigDecimal validation.
    */
   public void setMaxInclusive(final BigDecimal maxValue) {
     _max = maxValue;
     _hasMaxExclusive = false;
   } // -- setMaxInclusive
 
   /**
    * Sets the maximum number of digits for BigDecimal validation. To pass validation, a BigDecimal
    * must have this many digits or fewer. Leading zeros are not counted. Trailing zeros after the
    * decimal point are not counted.
    *
    * @param totalDig the maximum (inclusive) number of digits for BigDecimal validation. (must be >
    *        0)
    */
   public void setTotalDigits(final int totalDig) {
     if (totalDig <= 0) {
       throw new IllegalArgumentException(
           "DecimalValidator: the totalDigits facet must be positive");
     }
     _totalDigits = totalDig;
   }
 
   /**
    * Sets the maximum number of fraction digits for BigDecimal validation. To pass validation, a
    * BigDecimal must have this many digits or fewer following the decimal point. Trailing zeros
    * after the decimal point are not counted.
    *
    * @param fractionDig the maximum (inclusive) number of fraction digits for BigDecimal validation.
    *        (must be > 0)
    */
   public void setFractionDigits(final int fractionDig) {
     if (fractionDig < 0) {
       throw new IllegalArgumentException(
           "DecimalValidator: the fractionDigits facet must be positive");
     }
     _fractionDigits = fractionDig;
   }
 
   /**
    * Validates the given Object.
    *
    * @param bd the BigDecimal to validate
    * @param context the ValidationContext
    * @throws ValidationException if the object fails validation.
    */
   public void validate(final BigDecimal bd, final ValidationContext context)
       throws ValidationException {
     if (_fixed != null && !bd.equals(_fixed)) {
       String err = "BigDecimal " + bd + " is not equal to the fixed value: " + _fixed;
       throw new ValidationException(err);
     }
 
     if (_min != null) {
       if (bd.compareTo(_min) == -1) {
         String err = "BigDecimal " + bd + " is less than the minimum allowed value: " + _min;
         throw new ValidationException(err);
       } else if ((bd.compareTo(_min) == 0) && (_hasMinExclusive)) {
         String err =
             "BigDecimal " + bd + " cannot be equal to the minimum exclusive value: " + _min;
         throw new ValidationException(err);
       }
     }
 
     if (_max != null) {
       if (bd.compareTo(_max) == 1) {
         String err = "BigDecimal " + bd + " is greater than the maximum allowed value: " + _max;
         throw new ValidationException(err);
       } else if ((bd.compareTo(_max) == 0) && (_hasMaxExclusive)) {
         String err =
             "BigDecimal " + bd + " cannot be equal to the maximum exclusive value: " + _max;
         throw new ValidationException(err);
       }
     }
 
     // For digit counting, we are not supposed to count leading or trailing zeros
     BigDecimal clean = stripTrailingZeros(bd);
 
     if (_totalDigits != -1) {
       String temp = toStringForBigDecimal(clean);
       int length = temp.length();
       if (temp.indexOf('-') == 0) {
         --length;
       }
       if (temp.indexOf('.') != -1) {
         --length;
       }
       if (length > _totalDigits) {
         String err = "BigDecimal " + bd + " has too many significant digits -- must have "
             + _totalDigits + " or fewer";
         throw new ValidationException(err);
       }
       temp = null;
     }
 
     if (_fractionDigits != -1 && clean.scale() > _fractionDigits) {
       String err = "BigDecimal " + bd + " has too many fraction digits -- must have "
           + _fractionDigits + " fraction digits or fewer";
       throw new ValidationException(err);
     }
 
     if (hasPattern()) {
       super.validate(toStringForBigDecimal(bd), context);
     }
   } // -- validate
 
   /**
    * Validates the given Object.
    *
    * @param object the Object to validate
    * @throws ValidationException if the object fails validation.
    */
   public void validate(final Object object) throws ValidationException {
     validate(object, (ValidationContext) null);
   } // -- validate
 
   /**
    * Validates the given Object.
    *
    * @param object the Object to validate
    * @param context the ValidationContext
    * @throws ValidationException if the object fails validation.
    */
   public void validate(final Object object, final ValidationContext context)
       throws ValidationException {
     if (object == null) {
       String err = "decimalValidator cannot validate a null object.";
       throw new ValidationException(err);
     }
 
     BigDecimal value = null;
     if (object instanceof BigDecimal) {
       value = (BigDecimal) object;
     } else {
       try {
         value = new java.math.BigDecimal(object.toString());
       } catch (Exception ex) {
         String err = "Expecting a decimal, received instead: " + object.getClass().getName();
         throw new ValidationException(err);
       }
     }
     validate(value, context);
   } // -- validate
 
   /**
    * Because Sun broke API compatibility between Java 1.4 and Java 5, we have to do this the hard
    * way.
    *
    * @param bd the BigDecimal to toString() on.
    * @return what <i>should be</i> toString() for BigDecimal
    * @see <a href="http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=6364896"> This Sun bug report
    *      calling for better documentation of this change</a>
    */
   private String toStringForBigDecimal(final BigDecimal bd) {
     if (_bdMethodToPlainString != null) {
       try {
         // For Java 1.5 or later, use toPlainString() to get what we want
         return (String) _bdMethodToPlainString.invoke(bd, (Object[]) null);
       } catch (IllegalAccessException e) {
         // Cannot occur, so just fall through to toString()
       } catch (InvocationTargetException e) {
         // Cannot occur, so just fall through to toString()
       }
     }
 
     // For Java 1.4.2 or earlier, use toString() to get what we want
     return bd.toString();
   }
 
   /**
    * Trims trailing zeros from the provided BigDecimal. Since BigDecimals are immutable, the value
    * passed in is not changed.
    * <p>
    * The JDK 5 API provides a method to do this, but earlier releases of Java do not. Rather than
    * reflectively use this method for early releases and the API-provided one for releases after
    * Java 5, we'll just use this method for all Java releases.
    *
    * @param bd the BigDecimal to trim
    * @return a new BigDecimal with trailing zeros removed
    */
   private BigDecimal stripTrailingZeros(final BigDecimal bd) {
     BigDecimal ret = null;
     try {
       for (int i = bd.scale(); i >= 0; i--) {
         ret = bd.setScale(i);
       }
     } catch (ArithmeticException e) {
       // We've removed all trailing zeros
     }
     return (ret == null) ? bd : ret;
   }
 
 } // -- decimalValidator