package chart;

import java.awt.Graphics2D;
import java.awt.image.BufferedImage;
import java.io.ByteArrayOutputStream;
import java.io.OutputStream;
import java.util.ArrayList;
import java.util.List;

import org.eclipse.birt.chart.api.ChartEngine;
import org.eclipse.birt.chart.device.EmptyUpdateNotifier;
import org.eclipse.birt.chart.device.IDeviceRenderer;
import org.eclipse.birt.chart.device.IDisplayServer;
import org.eclipse.birt.chart.device.IImageMapEmitter;
import org.eclipse.birt.chart.exception.ChartException;
import org.eclipse.birt.chart.factory.GeneratedChartState;
import org.eclipse.birt.chart.factory.IGenerator;
import org.eclipse.birt.chart.model.ChartWithAxes;
import org.eclipse.birt.chart.model.attribute.ActionType;
import org.eclipse.birt.chart.model.attribute.AxisType;
import org.eclipse.birt.chart.model.attribute.Bounds;
import org.eclipse.birt.chart.model.attribute.IntersectionType;
import org.eclipse.birt.chart.model.attribute.LegendItemType;
import org.eclipse.birt.chart.model.attribute.Position;
import org.eclipse.birt.chart.model.attribute.TickStyle;
import org.eclipse.birt.chart.model.attribute.TriggerCondition;
import org.eclipse.birt.chart.model.attribute.impl.BoundsImpl;
import org.eclipse.birt.chart.model.attribute.impl.ColorDefinitionImpl;
import org.eclipse.birt.chart.model.attribute.impl.TextImpl;
import org.eclipse.birt.chart.model.attribute.impl.TooltipValueImpl;
import org.eclipse.birt.chart.model.component.Axis;
import org.eclipse.birt.chart.model.component.Series;
import org.eclipse.birt.chart.model.component.impl.LabelImpl;
import org.eclipse.birt.chart.model.component.impl.SeriesImpl;
import org.eclipse.birt.chart.model.data.NumberDataSet;
import org.eclipse.birt.chart.model.data.SeriesDefinition;
import org.eclipse.birt.chart.model.data.TextDataSet;
import org.eclipse.birt.chart.model.data.impl.ActionImpl;
import org.eclipse.birt.chart.model.data.impl.NumberDataSetImpl;
import org.eclipse.birt.chart.model.data.impl.SeriesDefinitionImpl;
import org.eclipse.birt.chart.model.data.impl.TextDataSetImpl;
import org.eclipse.birt.chart.model.data.impl.TriggerImpl;
import org.eclipse.birt.chart.model.impl.ChartWithAxesImpl;
import org.eclipse.birt.chart.model.layout.Plot;
import org.eclipse.birt.chart.model.type.BarSeries;
import org.eclipse.birt.chart.model.type.impl.BarSeriesImpl;
import org.eclipse.birt.core.framework.PlatformConfig;

import base64.Base64;

/**
 * A bar chart. The given data determines details like labeling and stacking/ grouping. The given data will be grouped
 * by columns and colored by lines. If {@link ChartDataSource#transpose()} is true this will be inverted.
 * 
 * Most of the code is copied from chart example code. There may be unnecessary lines of code.
 * 
 * @author me
 * 
 */
public class BarChart {
    /**
     * Delay for mouse hover tool tips.
     */
    private static final int TOOL_TIP_DELAY = 200;
    /**
     * Rotation of x axis labels.
     */
    private static final int X_ROTATION = 0;
    /**
     * Specifies png output.
     */
    private static final String PNG_F = "dv.PNG";
    /**
     * Specifies svg output.
     */
    private static final String SVG_F = "dv.SVG";
    /**
     * Images are rendered with this resolution. This is needed to scale them to a given pixel width and height.
     */
    private static final double DEFAULT_DPI = 72d;
    /**
     * The birt chart object.
     */
    private ChartWithAxes cwaBar = ChartWithAxesImpl.create();
    /**
     * Hold all needed data.
     */
    private ChartDataSource data;
    /**
     * x-axis.
     */
    private Axis xAxisPrimary;
    /**
     * y-axis.
     */
    private Axis yAxisPrimary;
    /**
     * For general settings.
     */
    private PlatformConfig pf = new PlatformConfig();
    /**
     * Instance of chart engine.
     */
    private ChartEngine ce;
    /**
     * Used to render all output formats.
     */
    private IDeviceRenderer dRenderer;
    /**
     * The bar series.
     */
    private List<BarSeries> barSeries;

    /**
     * Creates a chart from given data.
     * 
     * @param data
     *            contains all needed.
     */
    public BarChart(final ChartDataSource data) {
        this.data = data;
        // Standalone means - the chart is not embedded in a birt report.
        pf.setProperty("STANDALONE", true);
        ce = ChartEngine.instance(pf);
        prepareChart();
        setupAxes();
        setupData();
        setupTriggers();
        // set script to rearrange labels
        cwaBar.setScript("chart.AxisScript");
    }

    /**
     * Set ups mouse hover and other events.
     * 
     */
    private void setupTriggers() {
        for (BarSeries bs : barSeries) {
            bs.getDataPoint().setPrefix((String) bs.getSeriesIdentifier() + ": ");
            bs.getTriggers()
              .add(TriggerImpl.create(TriggerCondition.ONMOUSEOVER_LITERAL,
                                      ActionImpl.create(ActionType.SHOW_TOOLTIP_LITERAL,
                                                        TooltipValueImpl.create(TOOL_TIP_DELAY,
                                                                                null))));

        }

    }

    /**
     * Creates the "series" - the bars of the chart.
     */
    private void setupData() {
        TextDataSet categoryValues;
        List<NumberDataSet> dataSets = new ArrayList<NumberDataSet>();
        // normal
        if (data.transpose() == null || !data.transpose()) {
            categoryValues = TextDataSetImpl.create(data.columnLabels());
            // each line is one data set
            for (int i = 0; i < data.lineLabels().length; i++) {
                dataSets.add(NumberDataSetImpl.create(data.data()[i]));
            }
        } else {
            // grouped by lines not columns
            categoryValues = TextDataSetImpl.create(data.lineLabels());
            // iterate over columns
            for (int i = 0; i < data.columnLabels().length; i++) {
                // create array for each column
                Double[] column = new Double[data.lineLabels().length];
                // iterate over lines
                for (int j = 0; j < data.lineLabels().length; j++) {
                    column[j] = data.data()[j][i];
                }
                dataSets.add(NumberDataSetImpl.create(column));
            }
        }

        // X-Series
        Series seCategory = SeriesImpl.create();
        seCategory.setDataSet(categoryValues);
        SeriesDefinition sdX = SeriesDefinitionImpl.create();
        xAxisPrimary.getSeriesDefinitions().add(sdX);
        sdX.getSeries().add(seCategory);
        // sdX.getSeriesPalette().shift(0);

        barSeries = new ArrayList<BarSeries>();
        // creates a series definition for each group
        for (List<Integer> group : data.stackedLines()) {
            if (group != null && !group.isEmpty()) {
                SeriesDefinition groupSeries = SeriesDefinitionImpl.create();
                groupSeries.getSeriesPalette().shift(0);
                yAxisPrimary.getSeriesDefinitions().add(groupSeries);
                for (Integer integer : group) {
                    // new series for this stacked bar
                    BarSeries bs = (BarSeries) BarSeriesImpl.create();
                    barSeries.add(bs);
                    // add to series definition
                    groupSeries.getSeries().add(bs);
                    bs.setDataSet(dataSets.get(integer));
                    bs.setStacked(true);
                    if (data.transpose() == null || !data.transpose()) {
                        bs.setSeriesIdentifier(data.lineLabels()[integer]);
                        // mark line as added
                        data.lineLabels()[integer] = null;
                    } else {
                        bs.setSeriesIdentifier(data.columnLabels()[integer]);
                        // mark line as added
                        data.columnLabels()[integer] = null;
                    }
                }
            }
        }
        // now handle all not "used" lines or columns and add them to a unstacked series definition
        String[] rest = (data.transpose() == null || !data.transpose()) ? data.lineLabels() : data.columnLabels();
        SeriesDefinition unstackedSeries = null;
        for (int i = 0; i < rest.length; i++) {
            // check if added already
            if (rest[i] != null) {
                if (unstackedSeries == null) {
                    unstackedSeries = SeriesDefinitionImpl.create();
                    unstackedSeries.getSeriesPalette().shift(0);
                    yAxisPrimary.getSeriesDefinitions().add(unstackedSeries);
                }
                BarSeries bs = (BarSeries) BarSeriesImpl.create();
                barSeries.add(bs);
                bs.setSeriesIdentifier(rest[i]);
                bs.setDataSet(dataSets.get(i));
                unstackedSeries.getSeries().add(bs);
                // stacked is false by default
            }
        }

    }

    /**
     * Sets up x and y axis, including style of labels and caption.
     */
    private void setupAxes() {
        xAxisPrimary = cwaBar.getPrimaryBaseAxes()[0];
        xAxisPrimary.setType(AxisType.TEXT_LITERAL);
        xAxisPrimary.getMajorGrid().setTickStyle(TickStyle.BELOW_LITERAL);
        xAxisPrimary.getOrigin().setType(IntersectionType.MIN_LITERAL);
        xAxisPrimary.getLabel().getCaption().getFont().setRotation(X_ROTATION);

        yAxisPrimary = cwaBar.getPrimaryOrthogonalAxis(xAxisPrimary);
        yAxisPrimary.getMajorGrid().setTickStyle(TickStyle.LEFT_LITERAL);
        yAxisPrimary.setType(AxisType.LINEAR_LITERAL);
        if (data.relative() != null && data.relative()) {
            yAxisPrimary.setPercent(true);

        }
        org.eclipse.birt.chart.model.component.Label percent = LabelImpl.create();
        percent.setCaption(TextImpl.create(data.unit()));
        yAxisPrimary.setTitle(percent);
        yAxisPrimary.setLabelPosition(Position.LEFT_LITERAL);
        yAxisPrimary.getLabel().getCaption().getFont().setRotation(0);

    }

    /**
     * Sets up some chart layout stuff.
     */
    private void prepareChart() {
        // plot area
        cwaBar.getBlock().setBackground(ColorDefinitionImpl.WHITE());
        cwaBar.getBlock().getOutline().setVisible(true);
        Plot p = cwaBar.getPlot();
        p.getClientArea().setBackground(ColorDefinitionImpl.WHITE());
        // title
        cwaBar.getTitle().getLabel().getCaption().setValue(data.label());
        // legend
        cwaBar.getLegend().setItemType(LegendItemType.SERIES_LITERAL);
    }

    /**
     * Renders chart to {@link OutputStream} in given format.
     * 
     * @param out
     *            output stream
     * @param width
     *            in pixels
     * @param height
     *            in pixels
     * @param format
     *            desired output format
     */
    private void renderAsStream(final OutputStream out, final int width, final int height, final String format) {

        // Returns a singleton instance of the Generator
        IGenerator gr = ce.getGenerator();
        dRenderer = null;
        IDisplayServer dServer = null;
        GeneratedChartState gcs;
        try {
            // device renderers for dv.SWT, dv.PNG, dv.JPG
            // dv.PDF, dv.SVG, dv.SWING, dv.PNG24, div.BMP
            dRenderer = ce.getRenderer(format);
            dServer = dRenderer.getDisplayServer();
            dRenderer.setProperty(IDeviceRenderer.FILE_IDENTIFIER, out);
            Bounds bo = BoundsImpl.create(0, 0, width, height);
            // if not called the resolution will not be the set one.
            bo.scale(DEFAULT_DPI / dRenderer.getDisplayServer().getDpiResolution());
            gcs = gr.build(dServer, cwaBar, bo, null, null, null);
            // sets interactivity
            gcs.getRunTimeContext().setActionRenderer(new ChartActionRenderer(null));
            dRenderer.setProperty(IDeviceRenderer.UPDATE_NOTIFIER,
                                  new EmptyUpdateNotifier(cwaBar, gcs.getChartModel()));

            gr.render(dRenderer, gcs);
        } catch (ChartException e) {
            throw new IllegalStateException("Problem on rendering the chart. Cause: ", e);
        } catch (Exception ex) {
            throw new IllegalStateException("Problem on rendering the chart. Cause: ", ex);
        }
    }

    /**
     * Renders a svg graphic.
     * 
     * @param output
     *            output stream
     * @param width
     *            in pixels
     * @param height
     *            in pixels
     */
    public final void renderSVG(final OutputStream output, final int width, final int height) {
        renderAsStream(output, width, height, SVG_F);
    }

    /**
     * Renders png image.
     * 
     * @param output
     *            output stream
     * @param width
     *            in pixels
     * @param height
     *            in pixels
     */
    public final void renderPng(final OutputStream output, final Integer width, final Integer height) {
        renderAsStream(output, width, height, PNG_F);
    }

    /**
     * Same as {@link BarChart#renderPng(OutputStream, Integer, Integer)} but it returns a html imagemap for the
     * rendered image.
     * 
     * @param output
     *            will be filled with image
     * @param width
     *            in pixels
     * @param height
     *            in pixels
     * @return html image map for image
     */
    public final String renderPngWithImageMap(final OutputStream output, final Integer width, final Integer height) {
        renderAsStream(output, width, height, PNG_F);
        return ((IImageMapEmitter) dRenderer).getImageMap();
    }

    /**
     * Generates a html-div Element with an image map and the image embedded base64 encoded.
     * 
     * @param width
     *            in pixels
     * @param height
     *            in pixels
     * @return div with image map and embedded image.
     */
    public final String renderPngAsEmbeddedHtml(final Integer width, final Integer height) {
        StringBuilder result = new StringBuilder();
        ByteArrayOutputStream output = new ByteArrayOutputStream();
        renderPng(output, width, height);
        String imageMap = ((IImageMapEmitter) dRenderer).getImageMap();
        result.append("<div>");
        result.append("\r\n");
        result.append("<map name='pngmap'>");
        result.append(imageMap);
        result.append("</map>");
        result.append("\r\n");
        result.append("<img usemap='#pngmap' src=\"data:image/png;base64,");
        result.append(Base64.encodeToString(output.toByteArray(), true));
        result.append("\" >");
        result.append("\r\n");
        result.append("</div>");
        return result.toString();
    }

    /**
     * Renders a png image as BufferedImage.
     * 
     * @param width
     *            in pixels
     * @param height
     *            in pixels
     * @return png as an image
     */
    public final BufferedImage renderPng(final Integer width, final Integer height) {
        BufferedImage result = new BufferedImage(width, height, BufferedImage.TYPE_INT_ARGB);
        IGenerator gr = ce.getGenerator();
        IDisplayServer dServer = null;
        GeneratedChartState gcs;
        try {
            dRenderer = ce.getRenderer("dv.PNG");
            dRenderer.setProperty(IDeviceRenderer.GRAPHICS_CONTEXT, (Graphics2D) result.getGraphics());
            dRenderer.setProperty(IDeviceRenderer.CACHED_IMAGE, result);
            dServer = dRenderer.getDisplayServer();
            Bounds bo = BoundsImpl.create(0, 0, width, height);
            // if not called the resolution will not be the set one.
            bo.scale(DEFAULT_DPI / dRenderer.getDisplayServer().getDpiResolution());
            gcs = gr.build(dServer, cwaBar, bo, null, null, null);
            dRenderer.setProperty(IDeviceRenderer.UPDATE_NOTIFIER,
                                  new EmptyUpdateNotifier(cwaBar, gcs.getChartModel()));

            gr.render(dRenderer, gcs);
        } catch (ChartException e) {
            throw new IllegalStateException("Problem on rendering the chart. Cause: ", e);
        }
        return result;
    }
}

 NumberDataSet orthoValues1 = NumberDataSetImpl.create(new double[] {1, 2, 1.5, 2, 1.3});
NumberDataSet orthoValues2 = NumberDataSetImpl.create(new double[] {1, 1.1, 1.2, 1, 1.4});

yAxisPrimary.setFormatSpecifier(JavaNumberFormatSpecifierImpl.create("#.##"));