Force line wrapping in SVG text tags

src.js

(function() {
    var svgns = "http://www.w3.org/2000/svg";

    function forceTextWrappingOn(node, width) {
        console.log(node);
        var chars = node.firstChild.nodeValue.split(' '),
            x = parseInt(node.getAttribute('x'), 10),
            y = parseInt(node.getAttribute('y'), 10),
            index = 0,
            tspan, tspanWidth, textNode

            node.removeChild(node.firstChild);

        for (var c in chars) {
            if (chars.hasOwnProperty(c)) {
                tspanWidth = tspan == null ? 0 : tspan.getComputedTextLength();
                if (tspanWidth > width || tspanWidth === 0) {
                    y = y + 20;
                    tspan = document.createElementNS(svgns, 'tspan');
                    tspan.setAttribute('x', x);
                    tspan.setAttribute('y', y);
                    node.appendChild(tspan);
                    index = 0;
                }
                
                textNode = document.createTextNode(index === 0 ? chars[c] : " " + chars[c]);
                tspan.appendChild(textNode);
                index++;
            }
        }
    }
})();​

usage.html

<svg id="svg" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
  <text x="100" y="100">This text is really long isn't it!</text>
</svg>​

<script>
  var textNodes = document.querySelectorAll('text');

  for (var n in textNodes)
    if (textNodes.hasOwnProperty(n))
      forceTextWrappingOn(textNodes[n], 50);
</script>