eclipsecon08/org.eclipse.dltk.examples.python.part2/src/org/eclipse/dltk/python/internal/core/parsers/DLTKTokenConverter.java

package org.eclipse.dltk.python.internal.core.parsers;

import org.antlr.runtime.Token;
import org.eclipse.dltk.ast.DLTKToken;

public class DLTKTokenConverter {
	String content;
	CodeModel model;
	private static class CodeModel {
		private String[] codeLines;

		private int[] codeLineLengths;

		public CodeModel(String code) {
			this.codeLines = code.split("\n");
			int count = this.codeLines.length;

			this.codeLineLengths = new int[count];

			int sum = 0;
			for (int i = 0; i < count; ++i) {
				this.codeLineLengths[i] = sum;
				sum += this.codeLines[i].length() + 1;
			}
		}

		public int[] getBounds(int lineNumber) {
			String codeLine = codeLines[lineNumber];

			int start = codeLineLengths[lineNumber];
			int end = start + codeLine.length();

			return new int[] { start, end };
		}
	}
	public DLTKTokenConverter(char[] content0) {
		this.content = new String( content0 );
		this.model = new CodeModel(content);
	}

	public DLTKToken convert( Token token ) {
		if( token == null ) {
			DLTKToken t = new DLTKToken(0, "");
			t.setLine(1);
			return t;
		}
		int line = token.getLine()-1;
		if( line < 0 ) {
			line = 0;
		}
		int[] bounds = this.model.getBounds(line);
		
		DLTKToken t = new DLTKToken(token.getType(), token.getText());
		int offset = token.getCharPositionInLine();
		if( offset < 0 ) {
			offset = 0;
		}
		t.setColumn(bounds[0] + offset);
		t.setLine(line);
		return t;
	}
	public int convert( int line, int offset ) {
		int[] bounds = this.model.getBounds(line-1);
		return bounds[0] + offset;
	}

	public int length() {
		return this.content.length();
	}
}