1 /**

     2  * SQL-DK

     3  * Copyright © 2015 František Kučera (frantovo.cz)

     4  *

     5  * This program is free software: you can redistribute it and/or modify

     6  * it under the terms of the GNU General Public License as published by

     7  * the Free Software Foundation, either version 3 of the License, or

     8  * (at your option) any later version.

     9  *

    10  * This program is distributed in the hope that it will be useful,

    11  * but WITHOUT ANY WARRANTY; without even the implied warranty of

    12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the

    13  * GNU General Public License for more details.

    14  *

    15  * You should have received a copy of the GNU General Public License

    16  * along with this program. If not, see <http://www.gnu.org/licenses/>.

    17  */

    18 package info.globalcode.sql.dk.formatting;

    19 

    20 import info.globalcode.sql.dk.Functions;

    21 import info.globalcode.sql.dk.configuration.PropertyDeclaration;

    22 import info.globalcode.sql.dk.logging.LoggerProducer;

    23 import java.math.BigDecimal;

    24 import java.math.MathContext;

    25 import java.math.RoundingMode;

    26 import java.util.List;

    27 import java.util.logging.Level;

    28 import java.util.logging.Logger;

    29 

    30 /**

    31  * TODO: min/max values – range for case that no value is 100 %

    32  *

    33  * TODO: multiple barcharts in same table (last column is still default) + multiple resultsets

    34  *

    35  * TODO: negative values - bar starting from the middle, not always from the left

    36  *

    37  * @author Ing. František Kučera (frantovo.cz)

    38  */

    39 @PropertyDeclaration(name = BarChartFormatter.PROPERTY_PRECISION, type = Integer.class, defaultValue = BarChartFormatter.PROPERTY_PRECISION_DEFAULT, description = "number of characters representing 100 % in the bar chart")

    40 public class BarChartFormatter extends TabularPrefetchingFormatter {

    41 

    42 	public static final String NAME = "barchart"; // bash-completion:formatter

    43 	public static final String PROPERTY_PRECISION = "precision";

    44 	protected static final String PROPERTY_PRECISION_DEFAULT = "100";

    45 	private static final MathContext mathContext = MathContext.DECIMAL128;

    46 	public static final Logger log = LoggerProducer.getLogger();

    47 	private final BigDecimal chartPrecision;

    48 	private final char chartFull;

    49 	private final char chartEmpty;

    50 

    51 	public BarChartFormatter(FormatterContext formatterContext) {

    52 		super(formatterContext);

    53 		chartPrecision = BigDecimal.valueOf(formatterContext.getProperties().getInteger(PROPERTY_PRECISION, Integer.parseInt(PROPERTY_PRECISION_DEFAULT)));

    54 		chartFull = isAsciiNostalgia() ? '#' : '█';

    55 		chartEmpty = isAsciiNostalgia() ? '~' : '░';

    56 		// TODO: consider using partial blocks for more precision: https://en.wikipedia.org/wiki/Block_Elements

    57 	}

    58 

    59 	@Override

    60 	protected void postprocessPrefetchedResultSet(ColumnsHeader currentHeader, List<Object[]> currentResultSet) {

    61 		super.postprocessPrefetchedResultSet(currentHeader, currentResultSet);

    62 

    63 		updateColumnWidth(currentHeader.getColumnCount(), chartPrecision.intValue());

    64 

    65 		BigDecimal maximum = BigDecimal.ZERO;

    66 		BigDecimal minimum = BigDecimal.ZERO;

    67 		int lastIndex = currentHeader.getColumnCount() - 1;

    68 

    69 		Object valueObject = null;

    70 		try {

    71 			for (Object[] row : currentResultSet) {

    72 				valueObject = row[lastIndex];

    73 				if (valueObject != null) {

    74 					BigDecimal value = new BigDecimal(valueObject.toString());

    75 					maximum = maximum.max(value);

    76 					minimum = minimum.min(value);

    77 				}

    78 			}

    79 

    80 			BigDecimal range = maximum.subtract(minimum);

    81 

    82 			for (Object[] row : currentResultSet) {

    83 				valueObject = row[lastIndex];

    84 				if (valueObject == null) {

    85 					row[lastIndex] = "";

    86 				} else {

    87 					BigDecimal value = new BigDecimal(valueObject.toString());

    88 					BigDecimal valueFromMinimum = value.subtract(minimum);

    89 

    90 					BigDecimal points = chartPrecision.divide(range, mathContext).multiply(valueFromMinimum, mathContext);

    91 					int pointsRounded = points.setScale(0, RoundingMode.HALF_UP).intValue();

    92 					row[lastIndex] = Functions.repeat(chartFull, pointsRounded) + Functions.repeat(chartEmpty, chartPrecision.intValue() - pointsRounded);

    93 				}

    94 			}

    95 

    96 		} catch (NumberFormatException e) {

    97 			// https://en.wiktionary.org/wiki/parsable

    98 			log.log(Level.SEVERE, "Last column must be number or an object with toString() value parsable to a number. But was „{0}“", valueObject);

    99 			// FIXME: throw FormatterException

   100 			throw e;

   101 		}

   102 	}

   103 

   104 }