JSUtils.java

package com.drawbridge.utils;

import java.awt.Color;
import java.awt.Dimension;
import java.awt.Point;
import java.util.ArrayList;
import java.util.HashSet;
import java.util.LinkedList;
import java.util.List;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

import javax.swing.SwingUtilities;

import com.drawbridge.dm.DMImageFactory.DMImage;
import com.drawbridge.dm.DMSimplePanel;
import com.drawbridge.jsengine.JsEngine;
import com.drawbridge.text.TextPanel;
import com.google.caja.lexer.FilePosition;
import com.google.caja.lexer.InputSource;

public class JSUtils
{
	private static int nameIndex = 0;
	
	/**
	 * Generates valid JavaScript code to display a given set of DMImages
	 * @param ArrayList of DMImages Assignment ps:
	 * @return JavaScript code
	 */
	public static String generateDMImageJS(List<DMImage> images){
		String result = "// Draw the images on the canvas\n";
		for(int i = 0; i < images.size(); i++){
			String objectName = images.get(i).getName();
			Point loc = images.get(i).getPreferredLocation();
			Dimension size = images.get(i).getPreferredSize();
			
			result += "var " + objectName + " = loadImage(" + i + ", " + 
			(int) loc.getX() +  ", " + 
			(int) loc.getY() +  ", " + 
			(int) (size.getWidth() - ( 2 * images.get(i).getHandleThickness()))  + ", " + 
			(int) (size.getHeight() - ( 2 * images.get(i).getHandleThickness())) + ");";
			result += (i != images.size() -1) ? "\n" : "";
		}
		return result;
	}
	
	/**
	 * Generates valid JavaScript code to display the canvas
	 * @param ArrayList of DMImages
	 * @return JavaScript code
	 */
	public static String generateCanvasJS(){
		return "// Get the canvas so we can draw something\n" +
			   "var canvas = document.getElementById(\"myCanvas\");\n\n" +
			   "// Paint Background\n" + 
			   "var myColour = Colour.getRGB(255, 255, 255);\n" +
			   "canvas.setBackgroundColour(myColour);\n";
	}
	
	public static String generateImageName(){
		return "image" + nameIndex++;
	}


	public static final String JS_CANVAS_RESET = ("clear();");


	private static HashSet<String> keywords = new HashSet<String>(){
		private static final long	serialVersionUID	= 1019297538895274071L;

		{
			add("in");
			add("if");
			add("for");
			add("while");
			add("finally");
			add("var");
			add("new");
			add("function");
			add("do");
			add("return");
			add("void");
			add("else");
			add("break");
			add("catch");
			add("instanceof");
			add("with");
			add("throw");
			add("case");
			add("default");
			add("try");
			add("this");
			add("switch");
			add("continue");
			add("typeof");
			add("delete");
			add("let");
			add("yield");
			add("const");
			add("true");
			add("false");
			add("null");
			add("undefined");
			add("NaN");
			add("Infinity");
		}
		;
	};
	      
	
	public static ArrayList<HighlightElement> getHighlightElements(String javascript){
		ArrayList<HighlightElement> results = new ArrayList<HighlightElement>();
		ArrayList<HighlightElement> tokens = getMatchingKeywords(javascript);
		ArrayList<HighlightElement> stringLiterals = getStringLiterals(javascript);
		ArrayList<HighlightElement> literals = getLiterals(javascript);
		ArrayList<HighlightElement> comments = getComments(javascript);
		ArrayList<HighlightElement> functionCalls = getFunctionCalls(javascript);
		results.addAll(literals);
		results.addAll(tokens);
		results.addAll(stringLiterals);
		results.addAll(comments);
		results.addAll(functionCalls);
		return results;
	}
	

	public static ArrayList<HighlightElement> getMatchingKeywords(String string){
		ArrayList<HighlightElement> tokens = new ArrayList<HighlightElement>();
		String stringPattern = "(^|[\\s])[A-Za-z]+";
		Pattern pattern = Pattern.compile(stringPattern);
		Matcher matcher = pattern.matcher(string);
		while (matcher.find()) {
			String result = matcher.group().replaceAll("[\\s]", "");
			result = result.replaceAll("\\n", "");
			if(keywords.contains(result)){
				tokens.add(new HighlightElement(Color.decode("#BF2DA6"), matcher.start(), matcher.end()-1));
			}
		}
		return tokens;
	}
	
	public static ArrayList<HighlightElement> getStringLiterals(String string){
		ArrayList<HighlightElement> tokens = new ArrayList<HighlightElement>();
		String stringPattern = "[\'][\']*[\']";
		Pattern pattern = Pattern.compile(stringPattern);
		Matcher matcher = pattern.matcher(string);
		while (matcher.find()) {
			tokens.add(new HighlightElement(Color.decode("#D12B24"), matcher.start(), matcher.end()-1));
		}
		
		stringPattern = "[\"][^\"]*[\"]";
		pattern = Pattern.compile(stringPattern);
		matcher = pattern.matcher(string);
		while (matcher.find()) {
			tokens.add(new HighlightElement(Color.decode("#D12B24"), matcher.start(), matcher.end()-1));
		}
		
		return tokens;
	}
	
	public static ArrayList<HighlightElement> getComments(String string)
	{
		ArrayList<HighlightElement> tokens = new ArrayList<HighlightElement>();
		String stringPattern = "[\\/][\\/].*";
		Pattern pattern = Pattern.compile(stringPattern);
		Matcher matcher = pattern.matcher(string);
		while (matcher.find()) {
			tokens.add(new HighlightElement(Color.decode("#008425"), matcher.start(), matcher.end()-1));
		}
		return tokens;
	}
	
	public static ArrayList<HighlightElement> getFunctionCalls(String string)
	{
		ArrayList<HighlightElement> tokens = new ArrayList<HighlightElement>();
		String stringPattern = "[A-Za-z]+[(]";
		Pattern pattern = Pattern.compile(stringPattern);
		Matcher matcher = pattern.matcher(string);
		while (matcher.find()) {
			tokens.add(new HighlightElement(Color.decode("#42B5E7"), matcher.start(), matcher.end()-2));
		}
		return tokens;
	}
	
	public static ArrayList<HighlightElement> getLiterals(String string)
	{
		ArrayList<HighlightElement> tokens = new ArrayList<HighlightElement>();
		String stringPattern = "[\\(\\=\\,\\+\\-\\\\\\s][0-9]+[.]?[0-9]*";
		Pattern pattern = Pattern.compile(stringPattern);
		Matcher matcher = pattern.matcher(string);
		
		while (matcher.find()) {
			String startChar = string.substring(matcher.start(), matcher.start()+1);
			String allowedStartChars = "( +-=,";
			int start = matcher.start();
			int end = matcher.end() - 1;
			if(allowedStartChars.contains(startChar))
				start++;
				
			tokens.add(new HighlightElement(Color.decode("#049999"), start, end));
		}
		return tokens;
	}

	
	public static FilePosition getNewFilePosition(FilePosition oldFilePos, int newLength){
		if(oldFilePos.length() < newLength){
			return oldFilePos.narrowTo(0, newLength);
		}
		else{
			int linePos = oldFilePos.startLineNo();
			int oldStartCharInFile = oldFilePos.startCharInFile();
			int xPos = TextPanel.getInstance().getDocument().getDocumentModel().getCharPositionFromStringIndex(oldStartCharInFile-1).x;
			FilePosition newFilePos = FilePosition.instance(InputSource.UNKNOWN, linePos, oldStartCharInFile, xPos, newLength);
			return newFilePos;
		}
	}


	public static void printFilePosition(FilePosition filePosition)
	{
		Utils.out.println(JSUtils.class,"FilePosition: " + filePosition.startCharInFile() + ", " + filePosition.endCharInFile());
		
	}

	
	public static void executeStaticImageCode(LinkedList<DMImage> dmImages, final boolean requestAnimation)
	{
		// Follow on the update sequence with Code Generation
		String code = JSUtils.generateCanvasJS() + "\n";
		code += JSUtils.generateDMImageJS(dmImages);
		final String resultCode = code;

		
		SwingUtilities.invokeLater(new Runnable(){

			@Override
			public void run()
			{
				if(TextPanel.hasInstance())
					TextPanel.getInstance().setText(JSUtils.class, resultCode);
				

				JsEngine.getInstance().executeCode(null, resultCode, false); //<- this used to be important
				
				
				//Execute
				if(requestAnimation){
					Utils.out.println(this.getClass(),"Executing from DMModel");
					DMSimplePanel.getInstance().requestAnimationStart();
				}
			}
			
		});
	}

	public static void resetImageNameCounter()
	{
		nameIndex = 0;
	}

	
	
}