package ch.zhaw.ads;


import java.awt.*;


public class ServerGraphics {

	private StringBuffer b;
	private static ServerGraphics theGraphics;
  
	public static ServerGraphics instance() {
		if (theGraphics == null) {
			theGraphics = new ServerGraphics();
		}
		return theGraphics;
	}  

	public ServerGraphics() {
		clear();
		theGraphics = this;
	}

	public void clear() {
		b = new StringBuffer();
	}

	public String getTrace() {
		return new String(b);
	}

	private double round(double d) {
		return Math.round(d * 10000) / 10000.0;
	}
	
	private void drawFigure(String fig, String c1, String c2, String c3, String c4, double v1, double v2, double v3, double v4, String style) {
	    b.append("<");
	    b.append(fig); b.append(" ");
	    b.append(c1); b.append("=\"");
	    b.append(Double.toString(round(v1))); b.append("\" ");
	    b.append(c2); b.append("=\"");
	    b.append(Double.toString(round(v2))); b.append("\" ");	    
	    b.append(c3); b.append("=\"");
	    b.append(Double.toString(round(v3))); b.append("\" ");	   
	    b.append(c4); b.append("=\"");
	    b.append(Double.toString(round(v4))); b.append("\"");	
	    if (!"".equals(style)) {
	        b.append(" style=\""); b.append(style); b.append("\"");
	    }
	    b.append("/>\n");
	}
	
	public void drawOval(double x, double y, double w, double h) {
	    drawFigure("ellipse","cx","cy","rx","ry",x+w/2,y+h/2,w/2,h/2,"draw");
	}
	
	public void fillOval(double x, double y, double w, double h) {
	    drawFigure("ellipse","cx","cy","rx","ry",x+w/2,y+h/2,w/2,h/2,"fill");
	}

	public void drawLine(double x1, double y1, double x2, double y2) {
	    drawFigure("line","x1","y1","x2","y2",x1,y1,x2,y2,"");
	}

	public void drawRect(double x, double y, double w, double h) {
	    drawFigure("rect","x","y","width","height",x,y,w,h,"draw");
	}

	public void fillRect(double x, double y, double w, double h) {
	    drawFigure("rect","x","y","width","height",x,y,w,h,"fill");
	}
	
	public void drawString(String s, double x, double y) {
	    b.append("<text x=\"");
	    b.append(Double.toString(round(x)));
	    b.append("\" y=\"");
	    b.append(Double.toString(round(y)));
	    b.append("\"/>");
	    b.append(s);
	    b.append("</text>\n");
	}
  
	public void setColor(Color c) {
		b.append("<color red=\"");
		b.append(Integer.toString(c.getRed()));
		b.append("\" green=\"");
		b.append(Integer.toString(c.getGreen()));
		b.append("\" blue=\"");
		b.append(Integer.toString(c.getBlue()));
		b.append("\"/>\n");
	}
  
	public void drawPath(String from, String to, boolean line) {
		double scale = 11;
		double xh0 = from.charAt(0) - '0';
		double yh0 = from.charAt(2) - '0';
		double xh1 = to.charAt(0) - '0';
		double yh1 = to.charAt(2) - '0';
		double x0 = Math.min(xh0, xh1) / scale;
		double y0 = Math.min(yh0, yh1) / scale;
		double x1 = Math.max(xh0, xh1) / scale;
		double y1 = Math.max(yh0, yh1) / scale;
		double w = 1 / scale;
		if (line) {
			drawLine(x0 + w / 2, y0 + w / 2, x1 + w / 2, y1 + w / 2);
		} else {
			if (Math.abs(y0 - y1) < 1E-10) { 
				fillRect(x0, y0, x1 - x0 + w, w);
			} else {
				fillRect(x0, y0, w, y1 - y0 + w);
			}
		}
	}

}