// Shared QR SVG helpers for browser renderers.

(function () {
  function normalizeSvgMarkup(svg) {
    var markup = String(svg || '').trim();
    if (!markup) {
      return '';
    }

    return markup.replace(/^<\?xml[^>]*>\s*/i, '');
  }

  function stripBackground(svg) {
    var markup = String(svg || '').trim();
    if (!markup) {
      return '';
    }

    return markup
      .replace(/<path\b[^>]*fill="#ffffff"[^>]*d="M0 0h[^\"]*"[^>]*\s*\/>/i, '')
      .replace(/<path\b[^>]*fill="#ffffff"[^>]*d="M0 0h[^\"]*"[^>]*><\/path>/i, '')
      .replace(/<rect\b[^>]*fill="#ffffff"[^>]*x="0"[^>]*y="0"[^>]*width="\d+"[^>]*height="\d+"[^>]*\s*\/?>(?:<\/rect>)?/i, '');
  }

  function normalizePreviewSvg(svg) {
    var markup = normalizeSvgMarkup(stripBackground(svg));
    if (!markup || markup.charAt(0) !== '<') {
      return markup;
    }

    return markup.replace(/^<svg\b([^>]*)>/i, function (_match, attrText) {
      var attrs = String(attrText || '');
      if (!/\bwidth\s*=\s*/i.test(attrs)) {
        attrs += ' width="95%"';
      }
      if (!/\bheight\s*=\s*/i.test(attrs)) {
        attrs += ' height="95%"';
      }
      if (!/\bpreserveAspectRatio\s*=\s*/i.test(attrs)) {
        attrs += ' preserveAspectRatio="xMidYMid meet"';
      }
      if (!/\bstyle\s*=\s*/i.test(attrs)) {
        attrs += ' style="display:block;width:95%;height:95%;"';
      }
      return '<svg' + attrs + '>';
    });
  }

  window.pulseQrSvgUtils = {
    normalizeSvgMarkup: normalizeSvgMarkup,
    stripBackground: stripBackground,
    normalizePreviewSvg: normalizePreviewSvg
  };
}());