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 *  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
 *
 *      https://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
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package org.apache.tools.ant.types.selectors;

import java.io.File;

import org.apache.tools.ant.types.Comparison;
import org.apache.tools.ant.types.EnumeratedAttribute;
import org.apache.tools.ant.types.Parameter;

Selector that filters files based on their size.
Since:
1.5/**
 * Selector that filters files based on their size.
 *
 * @since 1.5
 */
public class SizeSelector extends BaseExtendSelector {

    
Constants for kilo, kibi etc /** Constants for kilo, kibi etc */
    private static final int  KILO = 1000;
    private static final int  KIBI = 1024;
    private static final int  KIBI_POS = 4;
    private static final int  MEGA = 1000000;
    private static final int  MEGA_POS = 9;
    private static final int  MEBI = 1048576;
    private static final int  MEBI_POS = 13;
    private static final long GIGA = 1000000000L;
    private static final int  GIGA_POS = 18;
    private static final long GIBI = 1073741824L;
    private static final int  GIBI_POS = 22;
    private static final long TERA = 1000000000000L;
    private static final int  TERA_POS = 27;
    private static final long TEBI = 1099511627776L;
    private static final int  TEBI_POS = 31;
    private static final int  END_POS = 36;

    
Used for parameterized custom selector /** Used for parameterized custom selector */
    public static final String SIZE_KEY = "value";
    
Used for parameterized custom selector /** Used for parameterized custom selector */
    public static final String UNITS_KEY = "units";
    
Used for parameterized custom selector /** Used for parameterized custom selector */
    public static final String WHEN_KEY = "when";

    private long size = -1;
    private long multiplier = 1;
    private long sizelimit = -1;
    private Comparison when = Comparison.EQUAL;

    
Returns a String object representing the specified
SizeSelector. This is "{sizeselector value: " + <"compare",
"less", "more", "equal"> + "}".
Returns:
a string describing this object/**
     * Returns a <code>String</code> object representing the specified
     * SizeSelector. This is "{sizeselector value: " + &lt;"compare",
     * "less", "more", "equal"&gt; + "}".
     * @return a string describing this object
     */
    public String toString() {
        return String.format("{sizeselector value: %d compare: %s}",
                sizelimit, when.getValue());
    }

    
A size selector needs to know what size to base its selecting on.
This will be further modified by the multiplier to get an
actual size limit.
Params:
size – the size to select against expressed in units./**
     * A size selector needs to know what size to base its selecting on.
     * This will be further modified by the multiplier to get an
     * actual size limit.
     *
     * @param size the size to select against expressed in units.
     */
    public void setValue(long size) {
        this.size = size;
        if (multiplier != 0 && size > -1) {
            sizelimit = size * multiplier;
        }
    }

    
Sets the units to use for the comparison. This is a little
complicated because common usage has created standards that
play havoc with capitalization rules. Thus, some people will
use "K" for indicating 1000's, when the SI standard calls for
"k". Others have tried to introduce "K" as a multiple of 1024,
but that falls down when you reach "M", since "m" is already
defined as 0.001.

To get around this complexity, a number of standards bodies
have proposed the 2^10 standard, and at least one has adopted
it. But we are still left with a populace that isn't clear on
how capitalization should work.

We therefore ignore capitalization as much as possible.
Completely mixed case is not possible, but all upper and lower
forms are accepted for all long and short forms. Since we have
no need to work with the 0.001 case, this practice works here.

This function translates all the long and short forms that a
unit prefix can occur in and translates them into a single
multiplier.
Params:
units – The units to compare the size to, using an
       EnumeratedAttribute./**
     * Sets the units to use for the comparison. This is a little
     * complicated because common usage has created standards that
     * play havoc with capitalization rules. Thus, some people will
     * use "K" for indicating 1000's, when the SI standard calls for
     * "k". Others have tried to introduce "K" as a multiple of 1024,
     * but that falls down when you reach "M", since "m" is already
     * defined as 0.001.
     * <p>
     * To get around this complexity, a number of standards bodies
     * have proposed the 2^10 standard, and at least one has adopted
     * it. But we are still left with a populace that isn't clear on
     * how capitalization should work.
     * <p>
     * We therefore ignore capitalization as much as possible.
     * Completely mixed case is not possible, but all upper and lower
     * forms are accepted for all long and short forms. Since we have
     * no need to work with the 0.001 case, this practice works here.
     * <p>
     * This function translates all the long and short forms that a
     * unit prefix can occur in and translates them into a single
     * multiplier.
     *
     * @param units The units to compare the size to, using an
     *        EnumeratedAttribute.
     */
    public void setUnits(ByteUnits units) {
        int i = units.getIndex();
        multiplier = 0;
        if (i > -1 && i < KIBI_POS) {
            multiplier = KILO;
        } else if (i < MEGA_POS) {
            multiplier = KIBI;
        } else if (i < MEBI_POS) {
            multiplier = MEGA;
        } else if (i < GIGA_POS) {
            multiplier = MEBI;
        } else if (i < GIBI_POS) {
            multiplier = GIGA;
        } else if (i < TERA_POS) {
            multiplier = GIBI;
        } else if (i < TEBI_POS) {
            multiplier = TERA;
        } else if (i < END_POS) {
            multiplier = TEBI;
        }
        if (multiplier > 0 && size > -1) {
            sizelimit = size * multiplier;
        }
    }

    
This specifies when the file should be selected, whether it be
when the file matches a particular size, when it is smaller,
or whether it is larger.
Params:
when – The comparison to perform, an EnumeratedAttribute./**
     * This specifies when the file should be selected, whether it be
     * when the file matches a particular size, when it is smaller,
     * or whether it is larger.
     *
     * @param when The comparison to perform, an EnumeratedAttribute.
     */
    public void setWhen(SizeComparisons when) {
        this.when = when;
    }

    
When using this as a custom selector, this method will be called.
It translates each parameter into the appropriate setXXX() call.
Params:
parameters – the complete set of parameters for this selector./**
     * When using this as a custom selector, this method will be called.
     * It translates each parameter into the appropriate setXXX() call.
     *
     * @param parameters the complete set of parameters for this selector.
     */
    @Override
    public void setParameters(Parameter... parameters) {
        super.setParameters(parameters);
        if (parameters != null) {
            for (Parameter parameter : parameters) {
                String paramname = parameter.getName();
                if (SIZE_KEY.equalsIgnoreCase(paramname)) {
                    try {
                        setValue(Long.parseLong(parameter.getValue()));
                    } catch (NumberFormatException nfe) {
                        setError("Invalid size setting "
                                + parameter.getValue());
                    }
                } else if (UNITS_KEY.equalsIgnoreCase(paramname)) {
                    ByteUnits units = new ByteUnits();
                    units.setValue(parameter.getValue());
                    setUnits(units);
                } else if (WHEN_KEY.equalsIgnoreCase(paramname)) {
                    SizeComparisons scmp = new SizeComparisons();
                    scmp.setValue(parameter.getValue());
                    setWhen(scmp);
                } else {
                    setError("Invalid parameter " + paramname);
                }
            }
        }
    }

    
Checks to make sure all settings are kosher. In this case, it
means that the size attribute has been set (to a positive value),
that the multiplier has a valid setting, and that the size limit
is valid. Since the latter is a calculated value, this can only
fail due to a programming error.

If a problem is detected, the setError() method is called.

/**
     * <p>Checks to make sure all settings are kosher. In this case, it
     * means that the size attribute has been set (to a positive value),
     * that the multiplier has a valid setting, and that the size limit
     * is valid. Since the latter is a calculated value, this can only
     * fail due to a programming error.
     * </p>
     * <p>If a problem is detected, the setError() method is called.
     * </p>
     */
    public void verifySettings() {
        if (size < 0) {
            setError("The value attribute is required, and must be positive");
        } else if (multiplier < 1) {
            setError("Invalid Units supplied, must be K,Ki,M,Mi,G,Gi,T,or Ti");
        } else if (sizelimit < 0) {
            setError("Internal error: Code is not setting sizelimit correctly");
        }
    }

    
The heart of the matter. This is where the selector gets to decide
on the inclusion of a file in a particular fileset.
Params:
basedir – A java.io.File object for the base directory.
filename – The name of the file to check.
file – A File object for this filename.
Returns:
whether the file should be selected or not./**
     * The heart of the matter. This is where the selector gets to decide
     * on the inclusion of a file in a particular fileset.
     *
     * @param basedir A java.io.File object for the base directory.
     * @param filename The name of the file to check.
     * @param file A File object for this filename.
     * @return whether the file should be selected or not.
     */
    @Override
    public boolean isSelected(File basedir, String filename, File file) {

        // throw BuildException on error
        validate();

        // Directory size never selected for
        if (file.isDirectory()) {
            return true;
        }
        long diff = file.length() - sizelimit;
        return when.evaluate(diff == 0 ? 0 : (int) (diff / Math.abs(diff)));
    }


    
Enumerated attribute with the values for units.

This treats the standard SI units as representing powers of ten,
as they should. If you want the powers of 2 that approximate
the SI units, use the first two characters followed by a
bi. So 1024 (2^10) becomes kibi,
1048576 (2^20) becomes mebi, 1073741824 (2^30)
becomes gibi, and so on. The symbols are also
accepted, and these are the first letter capitalized followed
by an i. Ki, Mi,
Gi, and so on. Capitalization variations on these
are also accepted.

This binary prefix system is approved by the IEC and appears on
its way for approval by other agencies, but it is not an SI
standard. It disambiguates things for us, though.
/**
     * Enumerated attribute with the values for units.
     * <p>
     * This treats the standard SI units as representing powers of ten,
     * as they should. If you want the powers of 2 that approximate
     * the SI units, use the first two characters followed by a
     * <code>bi</code>. So 1024 (2^10) becomes <code>kibi</code>,
     * 1048576 (2^20) becomes <code>mebi</code>, 1073741824 (2^30)
     * becomes <code>gibi</code>, and so on. The symbols are also
     * accepted, and these are the first letter capitalized followed
     * by an <code>i</code>. <code>Ki</code>, <code>Mi</code>,
     * <code>Gi</code>, and so on. Capitalization variations on these
     * are also accepted.
     * <p>
     * This binary prefix system is approved by the IEC and appears on
     * its way for approval by other agencies, but it is not an SI
     * standard. It disambiguates things for us, though.
     */
    public static class ByteUnits extends EnumeratedAttribute {
        
Returns:
the values as an array of strings/**
         * @return the values as an array of strings
         */
        public String[] getValues() {
            return new String[]{"K", "k", "kilo", "KILO",
                                "Ki", "KI", "ki", "kibi", "KIBI",
                                "M", "m", "mega", "MEGA",
                                "Mi", "MI", "mi", "mebi", "MEBI",
                                "G", "g", "giga", "GIGA",
                                "Gi", "GI", "gi", "gibi", "GIBI",
                                "T", "t", "tera", "TERA",
           /* You wish! */      "Ti", "TI", "ti", "tebi", "TEBI"
            };
        }
    }

    
Enumerated attribute with the values for size comparison.
/**
     * Enumerated attribute with the values for size comparison.
     */
    public static class SizeComparisons extends Comparison {
    }

}