contrib/com/codecommit/wicket/Chart.java

/*
 * Created on Dec 11, 2007
 */
package com.codecommit.wicket;

import java.awt.Color;
import java.awt.Dimension;
import java.lang.reflect.InvocationTargetException;
import java.util.concurrent.locks.ReadWriteLock;
import java.util.concurrent.locks.ReentrantReadWriteLock;

import org.apache.wicket.markup.ComponentTag;
import org.apache.wicket.markup.html.WebComponent;

/**
 * @author Daniel Spiewak
 */
public class Chart extends WebComponent {
	private static final long serialVersionUID = 1L;

	private IChartProvider provider;
	
	private StringBuilder url;
	private final ReadWriteLock lock = new ReentrantReadWriteLock();
	
	public Chart(String id, IChartProvider provider) {
		super(id);
		
		this.provider = provider;
	}
	
	@Override
	public boolean getStatelessHint() {
		return false;
	}
	
	public void invalidate() {
		lock.writeLock().lock();
		try {
			url = null;
		} finally {
			lock.writeLock().unlock();
		}
	}
	
	public CharSequence constructURL() {
		lock.writeLock().lock();
		try {
			if (url != null) {
				return url;
			}
			
			url = new StringBuilder("http://chart.apis.google.com/chart?");
			
			addParameter(url, "chs", render(provider.getSize()));
			addParameter(url, "chd", render(provider.getData()));
			addParameter(url, "cht", render(provider.getType()));
			addParameter(url, "chbh", render(provider.getBarWidth(), provider.getBarGroupSpacing()));
			addParameter(url, "chtt", render(provider.getTitle()));
			addParameter(url, "chdl", render(provider.getLegend()));
			addParameter(url, "chco", render(provider.getColors()));
			
			IChartFill bgFill = provider.getBackgroundFill();
			IChartFill fgFill = provider.getChartFill();
	
			StringBuilder fillParam = new StringBuilder();
	
			if (bgFill != null) {
				fillParam.append("bg,").append(render(bgFill));
			}
	
			if (fgFill != null) {
				if (fillParam.length() > 0) {
					fillParam.append('|');
				}
	
				fillParam.append("c,").append(render(fgFill));
			}
			
			if (fillParam.toString().trim().equals("")) {
				fillParam = null;
			}
	
			addParameter(url, "chf", fillParam);
	
			IChartAxis[] axes = provider.getAxes();
			addParameter(url, "chxt", renderTypes(axes));
			addParameter(url, "chxl", renderLabels(axes));
			addParameter(url, "chxp", renderPositions(axes));
			addParameter(url, "chxr", renderRanges(axes));
			addParameter(url, "chxs", renderStyles(axes));
			
			addParameter(url, "chg", render(provider.getGrid()));
			addParameter(url, "chm", render(provider.getShapeMarkers()));
			addParameter(url, "chm", render(provider.getRangeMarkers()));
			addParameter(url, "chls", render(provider.getLineStyles()));
			addParameter(url, "chm", render(provider.getFillAreas()));
			addParameter(url, "chl", render(provider.getPieLabels()));
	
			return url;
		} finally {
			lock.writeLock().unlock();
		}
	}
	
	private void addParameter(StringBuilder url, CharSequence param, CharSequence value) {
		if (value == null || value.length() == 0) {
			return;
		}
		
		if (url.charAt(url.length() - 1) != '?') {
			url.append('&');
		}
		
		url.append(param).append('=').append(value);
	}
	
	private CharSequence render(Dimension dim) {
		if (dim == null) {
			return null;
		}
		
		return new StringBuilder().append(dim.width).append('x').append(dim.height);
	}
	
	private CharSequence render(IChartData data) {
		if (data == null) {
			return null;
		}

		ChartDataEncoding encoding = data.getEncoding();
		
		StringBuilder back = new StringBuilder();
		back.append(render(encoding)).append(':');
		
		for (double[] set : data.getData()) {
			if (set == null || set.length == 0) {
				back.append(encoding.convert(-1, data.getMax()));
			} else {
				for (double value : set) {
					back.append(encoding.convert(value, data.getMax())).append(encoding.getValueSeparator());
				}
				
				if (back.substring(back.length() - encoding.getValueSeparator().length(), 
						back.length()).equals(encoding.getValueSeparator())) {
					back.setLength(back.length() - encoding.getValueSeparator().length());
				}
			}
			
			back.append(encoding.getSetSeparator());
		}
		
		if (back.substring(back.length() - encoding.getSetSeparator().length(), 
				back.length()).equals(encoding.getSetSeparator())) {
			back.setLength(back.length() - encoding.getSetSeparator().length());
		}
		
		return back;
	}
	
	private CharSequence render(Enum<?> value) {
		if (value == null) {
			return null;
		}
		
		try {
			Object back = value.getClass().getMethod("getRendering").invoke(value);
			
			if (back != null) {
				return back.toString();
			}
		} catch (IllegalArgumentException e) {
		} catch (SecurityException e) {
		} catch (IllegalAccessException e) {
		} catch (InvocationTargetException e) {
		} catch (NoSuchMethodException e) {
		}
		
		return null;
	}
	
	private CharSequence render(int barWidth, int groupSpacing) {
		if (barWidth == -1) {
			return null;
		}
		
		StringBuilder back = new StringBuilder(barWidth);
		
		if (groupSpacing >= 0) {
			back.append(',').append(groupSpacing);
		}
		
		return back;
	}
	
	private CharSequence render(String[] values) {
		if (values == null) {
			return null;
		}
		
		StringBuilder back = new StringBuilder();
		
		for (String value : values) {
			CharSequence toRender = render(value);
			if (toRender == null) {
				toRender = "";
			}
			
			back.append(toRender).append('|');
		}
		
		if (back.length() > 0) {
			back.setLength(back.length() - 1);
		}
		
		return back;
	}
	
	private CharSequence render(String value) {
		if (value == null) {
			return value;
		}
		
		StringBuilder back = new StringBuilder();
		
		for (char c : value.toCharArray()) {
			if (c == ' ') {
				back.append('+');
			} else {
				back.append(c);
			}
		}
		
		return back;
	}
	
	private CharSequence render(Color[] values) {
		if (values == null) {
			return null;
		}
		
		StringBuilder back = new StringBuilder();
		
		for (Color value : values) {
			CharSequence toRender = render(value);
			if (toRender == null) {
				continue;
			}
			char delimiter = ',';
			switch(provider.getType()) {
			case PIE:
			case PIE_3D:
			case BAR_VERTICAL_SET:
				delimiter = '|';
				break;
			}
			back.append(toRender).append(delimiter);
		}
		
		if (back.length() > 0) {
			back.setLength(back.length() - 1);
		}
		
		return back;
	}
	
	private CharSequence render(Color value) {
		if (value == null) {
			return null;
		}
		
		StringBuilder back = new StringBuilder();
		
		{
			String toPad = Integer.toHexString(value.getRed());
			
			if (toPad.length() == 1) {
				back.append(0);
			}
			back.append(toPad);
		}
		
		{
			String toPad = Integer.toHexString(value.getGreen());
			
			if (toPad.length() == 1) {
				back.append(0);
			}
			back.append(toPad);
		}
		
		{
			String toPad = Integer.toHexString(value.getBlue());
			
			if (toPad.length() == 1) {
				back.append(0);
			}
			back.append(toPad);
		}
		
		{
			String toPad = Integer.toHexString(value.getAlpha());
			
			if (toPad.length() == 1) {
				back.append(0);
			}
			back.append(toPad);
		}
		
		return back;
	}
	
	private CharSequence render(IChartFill fill) {
		if (fill == null) {
			return null;
		}
		
		StringBuilder back = new StringBuilder();
		
		if (fill instanceof ISolidFill) {
			ISolidFill solidFill = (ISolidFill) fill;
			
			back.append("s,");
			back.append(render(solidFill.getColor()));
		} else if (fill instanceof ILinearGradientFill) {
			ILinearGradientFill gradientFill = (ILinearGradientFill) fill;
			
			back.append("lg,").append(gradientFill.getAngle()).append(',');
			
			Color[] colors = gradientFill.getColors();
			double[] offsets = gradientFill.getOffsets();
			for (int i = 0; i < colors.length; i++) {
				back.append(render(colors[i])).append(',').append(offsets[i]).append(',');
			}
			
			back.setLength(back.length() - 1);
		} else if (fill instanceof ILinearStripesFill) {
			ILinearStripesFill stripesFill = (ILinearStripesFill) fill;
			
			back.append("ls,").append(stripesFill.getAngle()).append(',');
			
			Color[] colors = stripesFill.getColors();
			double[] widths = stripesFill.getWidths();
			for (int i = 0; i < colors.length; i++) {
				back.append(render(colors[i])).append(',').append(widths[i]).append(',');
			}
			
			back.setLength(back.length() - 1);
		} else {
			return null;
		}
		
		return back;
	}
	
	private CharSequence renderTypes(IChartAxis[] axes) {
		if (axes == null) {
			return null;
		}
		
		StringBuilder back = new StringBuilder();
		
		for (IChartAxis axis : axes) {
			back.append(render(axis.getType())).append(',');
		}
		
		if (back.length() > 0) {
			back.setLength(back.length() - 1);
		}
		
		return back;
	}
	
	private CharSequence renderLabels(IChartAxis[] axes) {
		if (axes == null) {
			return null;
		}
		
		StringBuilder back = new StringBuilder();
		
		for (int i = 0; i < axes.length; i++) {
			if (axes[i] == null || axes[i].getLabels() == null) {
				continue;
			}
			
			back.append(i).append(":|");
			
			for (String label : axes[i].getLabels()) {
				if (label == null) {
					back.append('|');
					continue;
				}
				
				back.append(render(label)).append('|');
			}
			
			if (i == axes.length - 1) {
				back.setLength(back.length() - 1);
			}
		}
		
		return back;
	}
	
	private CharSequence renderPositions(IChartAxis[] axes) {
		if (axes == null) {
			return null;
		}
		
		StringBuilder back = new StringBuilder();
		
		for (int i = 0; i < axes.length; i++) {
			if (axes[i] == null || axes[i].getPositions() == null) {
				continue;
			}
			
			back.append(i).append(',');
			
			for (double position : axes[i].getPositions()) {
				back.append(position).append(',');
			}
			
			back.setLength(back.length() - 1);
			
			back.append('|');
		}
		
		if (back.length() > 0) {
			back.setLength(back.length() - 1);
		}
		
		return back;
	}
	
	private CharSequence renderRanges(IChartAxis[] axes) {
		if (axes == null) {
			return null;
		}
		
		StringBuilder back = new StringBuilder();
		
		for (int i = 0; i < axes.length; i++) {
			if (axes[i] == null || axes[i].getRange() == null) {
				continue;
			}
			
			back.append(i).append(',');
			
			Range range = axes[i].getRange();
			back.append(range.getStart()).append(',').append(range.getEnd()).append('|');
		}
		
		if (back.length() > 0) {
			back.setLength(back.length() - 1);
		}
		
		return back;
	}
	
	private CharSequence renderStyles(IChartAxis[] axes) {
		if (axes == null) {
			return null;
		}
		
		StringBuilder back = new StringBuilder();
		
		for (int i = 0; i < axes.length; i++) {
			if (axes[i] == null || axes[i].getColor() == null 
					|| axes[i].getFontSize() < 0 || axes[i].getAlignment() == null) {
				continue;
			}
			
			back.append(i).append(',');
			back.append(render(axes[i].getColor())).append(',');
			back.append(axes[i].getFontSize()).append(',');
			back.append(render(axes[i].getAlignment())).append('|');
		}
		
		if (back.length() > 0) {
			back.setLength(back.length() - 1);
		}
		
		return back;
	}
	
	private CharSequence render(IChartGrid grid) {
		if (grid == null) {
			return null;
		}
		
		StringBuilder back = new StringBuilder();
		
		back.append(grid.getXStepSize()).append(',');
		back.append(grid.getYStepSize());
		
		if (grid.getSegmentLength() >= 0) {
			back.append(',').append(grid.getSegmentLength());
			back.append(',').append(grid.getBlankLength());
		}
		
		return back;
	}
	
	private CharSequence render(IShapeMarker[] markers) {
		if (markers == null) {
			return null;
		}
		
		StringBuilder back = new StringBuilder();
		
		for (IShapeMarker marker : markers) {
			back.append(render(marker.getType())).append(',');
			back.append(render(marker.getColor())).append(',');
			back.append(marker.getIndex()).append(',');
			back.append(marker.getPoint()).append(',');
			back.append(marker.getSize()).append('|');
		}
		
		if (back.length() > 0) {
			back.setLength(back.length() - 1);
		}
		
		return back;
	}
	
	private CharSequence render(IRangeMarker[] markers) {
		if (markers == null) {
			return null;
		}
		
		StringBuilder back = new StringBuilder();
		
		for (IRangeMarker marker : markers) {
			back.append(render(marker.getType())).append(',');
			back.append(render(marker.getColor())).append(',');
			back.append(0).append(',');
			back.append(marker.getStart()).append(',');
			back.append(marker.getEnd()).append('|');
		}
		
		if (back.length() > 0) {
			back.setLength(back.length() - 1);
		}
		
		return back;
	}
	
	private CharSequence render(IFillArea[] areas) {
		if (areas == null) {
			return null;
		}
		
		StringBuilder back = new StringBuilder();
		
		for (IFillArea area : areas) {
			back.append(render(area.getType())).append(',');
			back.append(render(area.getColor())).append(',');
			back.append(area.getStartIndex()).append(',');
			back.append(area.getEndIndex()).append(',');
			back.append(0).append('|');
		}
		
		if (back.length() > 0) {
			back.setLength(back.length() - 1);
		}
		
		return back;
	}
	
	private CharSequence render(ILineStyle[] styles) {
		if (styles == null) {
			return null;
		}
		
		StringBuilder back = new StringBuilder();
		
		for (ILineStyle style : styles) {
			if (style == null) {
				back.append('|');
				continue;
			}
			
			back.append(style.getThickness()).append(',');
			back.append(style.getSegmentLength()).append(',');
			back.append(style.getBlankLength()).append('|');
		}
		
		if (back.length() > 0) {
			back.setLength(back.length() - 1);
		}
		
		return back;
	}
	
	@Override
	protected void onComponentTag(ComponentTag tag) {
		checkComponentTag(tag, "img");
		super.onComponentTag(tag);
		
		tag.put("src", constructURL());
	}
}