CumulativeFlowChartBuilder.java

package com.metservice.kanban.charts.cumulativeflow;

import static com.metservice.kanban.utils.DateUtils.currentLocalDate;
import java.awt.Color;
import java.io.IOException;
import java.util.List;
import org.jfree.chart.ChartFactory;
import org.jfree.chart.JFreeChart;
import org.jfree.chart.annotations.CategoryPointerAnnotation;
import org.jfree.chart.axis.CategoryAxis;
import org.jfree.chart.axis.CategoryLabelPositions;
import org.jfree.chart.axis.NumberAxis;
import org.jfree.chart.plot.CategoryPlot;
import org.jfree.chart.plot.PlotOrientation;
import org.jfree.data.category.CategoryDataset;
import org.jfree.data.general.DatasetUtilities;
import org.joda.time.LocalDate;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import com.metservice.kanban.charts.ChartUtils;
import com.metservice.kanban.charts.KanbanDrawingSupplier;
import com.metservice.kanban.model.KanbanJournalItem;
import com.metservice.kanban.model.KanbanProject;
import com.metservice.kanban.model.WorkItem;
import com.metservice.kanban.utils.Day;
import com.metservice.kanban.utils.WorkingDayUtils;

public class CumulativeFlowChartBuilder {

    private static final Logger LOGGER = LoggerFactory.getLogger(CumulativeFlowChartBuilder.class);

    private LocalDate startDate;
    private LocalDate endDate;

    public CumulativeFlowChartBuilder(LocalDate startDate, LocalDate endDate) {
        this.startDate = startDate;
        this.endDate = endDate;
    }

    public CategoryDataset createDataset(List<String> phases, List<WorkItem> workItemList) throws IOException {
        // add start date and end date instead of local date here
        if (endDate == null) {
            endDate = currentLocalDate();
        }
        if (startDate == null) {
            startDate = ChartUtils.getFirstDate(workItemList);

            if (startDate == null) {
                startDate = endDate;
            }
        }
        CumulativeFlowChartMatrix matrix = new CumulativeFlowChartMatrix(phases, startDate, endDate);
        for (WorkItem workItem : workItemList) {
            matrix.registerWorkItem(workItem);
        }

        List<LocalDate> dates = matrix.getOrderedListOfDates();
        double[][] data = matrix.getData();
        Day[] days = getListOfDays(dates);

        return DatasetUtilities.createCategoryDataset(getPhasesInInverseOrder(phases), days, data);
    }

    private String[] getPhasesInInverseOrder(List<String> phases) {
        String[] invertedPhases = new String[phases.size()];
        int k = phases.size() - 1;
        for (String phase : phases) {
            invertedPhases[k--] = phase;
        }
        return invertedPhases;
    }

    public JFreeChart createChart(CategoryDataset dataset, KanbanProject project) {

        JFreeChart chart = ChartFactory.createStackedAreaChart(
            "Cumulative Flow Chart", // chart title
            "", // domain axis label
            "", // range axis label
            dataset, // data
            PlotOrientation.VERTICAL, // orientation
            true, // include legend
            true,
            false
            );

        CategoryPlot plot = (CategoryPlot) chart.getPlot();

        plot.setForegroundAlpha(1f);
        plot.setBackgroundPaint(Color.WHITE);
        plot.setDomainGridlinesVisible(true);
        plot.setDomainGridlinePaint(Color.GRAY);
        plot.setRangeGridlinePaint(Color.GRAY);
        plot.setDrawingSupplier(new KanbanDrawingSupplier(dataset.getRowCount()));

        insertJournalEntries(dataset, project, plot, ((Day) dataset.getColumnKey(0)).getDate(),
            ((Day) dataset.getColumnKey(dataset.getColumnCount() - 1)).getDate());

        final CategoryAxis domainAxis = plot.getDomainAxis();
        domainAxis.setLowerMargin(0.0);
        domainAxis.setUpperMargin(0.0);
        domainAxis.setCategoryLabelPositions(CategoryLabelPositions.UP_90);

        // change the auto tick unit selection to integer units only...
        final NumberAxis rangeAxis = (NumberAxis) plot.getRangeAxis();
        rangeAxis.setStandardTickUnits(NumberAxis.createIntegerTickUnits());
        // this is to show annotations when they are above the chart
        rangeAxis.setUpperMargin(0.12);

        return chart;
    }

    public static void insertJournalEntries(CategoryDataset dataset, KanbanProject project, CategoryPlot plot,
                                            LocalDate startDate, LocalDate endDate) {
        for (KanbanJournalItem journalItem : project.getJournal()) {
            // check if the item is visible on the chart
            if (!journalItem.getDate().toLocalDate().isBefore(startDate)
                && !journalItem.getDate().toLocalDate().isAfter(endDate)) {

                int columnId = WorkingDayUtils.getWorkingDaysBetween(startDate, journalItem.getDate().toLocalDate());

                if (columnId < dataset.getColumnCount()) {
                    String text;
                    if (journalItem.getText().length() > 12) {
                        text = journalItem.getText().substring(0, 10) + "...";
                    } else {
                        text = journalItem.getText();
                    }

                    int yValue = 0;
                    for (int i = 0; i < dataset.getRowCount(); i++) {
                        yValue += dataset.getValue(i, columnId).intValue();
                    }

                    CategoryPointerAnnotation annotation = new CategoryPointerAnnotation(text,
                        dataset.getColumnKey(columnId), yValue, 30);
                    annotation.setBaseRadius(30);
                    annotation.setLabelOffset(7);
                    plot.addAnnotation(annotation);
                } else {
                    LOGGER.warn("Cannot display journal entry {} for day {}, not sure why", journalItem.getText(),
                        journalItem.getDate());
                }
            }
        }
    }

    private Day[] getListOfDays(List<LocalDate> dates) {
        Day[] days = new Day[dates.size()];
        int i = 0;
        for (LocalDate date : dates) {
            days[i++] = new Day(date);
        }
        return days;
    }

}