BEGIN LICENSE BLOCK *****
Version: EPL 2.0/GPL 2.0/LGPL 2.1
The contents of this file are subject to the Eclipse Public
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.eclipse.org/legal/epl-v20.html
Software distributed under the License is distributed on an "AS
IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
implied. See the License for the specific language governing
rights and limitations under the License.
Alternatively, the contents of this file may be used under the terms of
either of the GNU General Public License Version 2 or later (the "GPL"),
or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
in which case the provisions of the GPL or the LGPL are applicable instead
of those above. If you wish to allow use of your version of this file only
under the terms of either the GPL or the LGPL, and not to allow others to
use your version of this file under the terms of the EPL, indicate your
decision by deleting the provisions above and replace them with the notice
and other provisions required by the GPL or the LGPL. If you do not delete
the provisions above, a recipient may use your version of this file under
the terms of any one of the EPL, the GPL or the LGPL.
END LICENSE BLOCK /***** BEGIN LICENSE BLOCK *****
 * Version: EPL 2.0/GPL 2.0/LGPL 2.1
 *
 * The contents of this file are subject to the Eclipse Public
 * 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.eclipse.org/legal/epl-v20.html
 *
 * Software distributed under the License is distributed on an "AS
 * IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
 * implied. See the License for the specific language governing
 * rights and limitations under the License.
 *
 * Alternatively, the contents of this file may be used under the terms of
 * either of the GNU General Public License Version 2 or later (the "GPL"),
 * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
 * in which case the provisions of the GPL or the LGPL are applicable instead
 * of those above. If you wish to allow use of your version of this file only
 * under the terms of either the GPL or the LGPL, and not to allow others to
 * use your version of this file under the terms of the EPL, indicate your
 * decision by deleting the provisions above and replace them with the notice
 * and other provisions required by the GPL or the LGPL. If you do not delete
 * the provisions above, a recipient may use your version of this file under
 * the terms of any one of the EPL, the GPL or the LGPL.
 ***** END LICENSE BLOCK *****/

package org.jruby.util;

Support for GNU-C output formatters, see: http://www.gnu.org/software/libc/manual/html_node/Formatting-Calendar-Time.html
/**
 * Support for GNU-C output formatters, see: http://www.gnu.org/software/libc/manual/html_node/Formatting-Calendar-Time.html
 */
@Deprecated
public class TimeOutputFormatter {
    final String format;
    final int width;

    public final static TimeOutputFormatter DEFAULT_FORMATTER = new TimeOutputFormatter("", 0);

    public TimeOutputFormatter(String format, int width) {
        this.format = format;
        this.width = width;
    }

    // Really ugly stop-gap method to eliminate using regexp for create TimeOutputFormatter.
    // FIXME: Make all of strftime an honest to goodness parser
    public static TimeOutputFormatter getFormatter(String pattern) {
        int length = pattern.length();
        
        if (length <= 1 || pattern.charAt(0) != '%') {
           return null;
        }

        int width = 0;
        
        int i = 1;
        boolean done = false;
        boolean formatterFound = false;
        
        for (; i < length && !done; i++) {
            char c = pattern.charAt(i);
            switch(c) {
                case '-': case '_': case '0': case '^': case '#': case ':':
                    formatterFound = true;
                    break;
                case '1': case '2': case '3': case '4': case '5': 
                case '6': case '7': case '8': case '9':
                    width = Character.getNumericValue(c);
                    done = true;
                    break;
                default:
                    done = true;
                    break;
            }
        }
        
        if (width == 0 && !formatterFound) return null;
        
        String format;
        if (i > 2) { // found something
            format = pattern.substring(1, i-1);
        } else {
            format = "";
        }

        // We found some formatting instructions but no padding values.
        if (width == 0 && i > 2) {
            return new TimeOutputFormatter(format, 0);
        }
        
        done = false;
        for (; i < length && !done; i++) {
            char c = pattern.charAt(i);
            
            switch(c) {
                case '1': case '2': case '3': case '4': case '5': 
                case '6': case '7': case '8': case '9': case '0':
                    width = 10 * width + Character.getNumericValue(c);
                    break;
                case ':':
                    format += ':'; /* Make it part of the format */
                    break;
                default:
                    done = true;
                    break;
            }
        }
        
        if (width != 0) {
            return new TimeOutputFormatter(format, width);
        }

        return null;
    }

    public String getFormat() {
        return format + (width > 0 ? width : "");
    }

    public int getNumberOfColons() {
        int colons = 0;
        for (int i = 0; i < format.length(); i++) {
            if (format.charAt(i) == ':') {
                colons++;
            }
        }
        return colons;
    }

    public int getWidth(int defaultWidth) {
        if (format.contains("-")) { // no padding
            return 0;
        }
        return this.width != 0 ? this.width : defaultWidth; 
    }

    public char getPadder(char defaultPadder) {
        char padder = defaultPadder;
        for (int i = 0; i < format.length(); i++) {
            switch (format.charAt(i)) {
                case '_':
                    padder = ' ';
                    break;
                case '0':
                    padder = '0';
                    break;
                case '-': // no padding
                    padder = '\0';
                    break;
            }
        }
        return padder;
    }

    public String format(String sequence, long value, org.jruby.util.RubyDateFormat.FieldType type) {
        int width = getWidth(type.defaultWidth);
        char padder = getPadder(type.defaultPadder);

        if (sequence == null) {
            sequence = formatNumber(value, width, padder);
        } else {
            sequence = padding(sequence, width, padder);
        }

        for (int i = 0; i < format.length(); i++) {
            switch (format.charAt(i)) {
                case '^':
                    sequence = sequence.toUpperCase();
                    break;
                case '#': // change case
                    char last = sequence.charAt(sequence.length() - 1);
                    if (Character.isLowerCase(last)) {
                        sequence = sequence.toUpperCase();
                    } else {
                        sequence = sequence.toLowerCase();
                    }
                    break;
            }
        }

        return sequence;
    }

    static String formatNumber(long value, int width, char padder) {
        if (value >= 0 || padder != '0') {
            return padding(Long.toString(value), width, padder);
        } else {
            return "-" + padding(Long.toString(-value), width - 1, padder);
        }
    }

    static String formatSignedNumber(long value, int width, char padder) {
        if (padder == '0') {
            if (value >= 0) {
                return "+" + padding(Long.toString(value), width - 1, padder);
            } else {
                return "-" + padding(Long.toString(-value), width - 1, padder);
            }
        } else {
            if (value >= 0) {
                return padding("+" + Long.toString(value), width, padder);
            } else {
                return padding(Long.toString(value), width, padder);
            }
        }
    }

    static String padding(String sequence, int width, char padder) {
        if (sequence.length() >= width) {
            return sequence;
        }

        StringBuilder buf = new StringBuilder(width + sequence.length());
        for (int i = sequence.length(); i < width; i++) {
            buf.append(padder);
        }
        buf.append(sequence);
        return buf.toString();
    }
}