text: import { inheritableAttrs, pathElems } from "./_collections.js";
  
  export const type = "perItemReverse";
  
  export const active = true;
  
  export const description =
    "moves elements attributes to the existing group wrapper";
  
  /**
   * Collapse content's intersected and inheritable
   * attributes to the existing group wrapper.
   *
   * @example
   * <g attr1="val1">
   *     <g attr2="val2">
   *         text
   *     </g>
   *     <circle attr2="val2" attr3="val3"/>
   * </g>
   *              ⬇
   * <g attr1="val1" attr2="val2">
   *     <g>
   *         text
   *     </g>
   *    <circle attr3="val3"/>
   * </g>
   *
   * @param {Object} item current iteration item
   * @return {Boolean} if false, item will be filtered out
   *
   * @author Kir Belevich
   */
  export function fn(item) {
    if (
      item.type === "element" &&
      item.name === "g" &&
      item.children.length > 1
    ) {
      var intersection = {},
        hasTransform = false,
        hasClip = item.attributes["clip-path"] != null ||
          item.attributes.mask != null,
        intersected = item.children.every(function (inner) {
          if (
            inner.type === "element" &&
            Object.keys(inner.attributes).length !== 0
          ) {
            // don't mess with possible styles (hack until CSS parsing is implemented)
            if (inner.attributes.class) return false;
            if (!Object.keys(intersection).length) {
              intersection = inner.attributes;
            } else {
              intersection = intersectInheritableAttrs(
                intersection,
                inner.attributes,
              );
  
              if (!intersection) return false;
            }
  
            return true;
          }
  
          return false;
        }),
        allPath = item.children.every(function (inner) {
          return inner.isElem(pathElems);
        });
  
      if (intersected) {
        item.children.forEach(function (g) {
          for (const [name, value] of Object.entries(intersection)) {
            if ((!allPath && !hasClip) || name !== "transform") {
              delete g.attributes[name];
  
              if (name === "transform") {
                if (!hasTransform) {
                  if (item.attributes.transform != null) {
                    item.attributes.transform = item.attributes.transform + " " +
                      value;
                  } else {
                    item.attributes.transform = value;
                  }
  
                  hasTransform = true;
                }
              } else {
                item.attributes[name] = value;
              }
            }
          }
        });
      }
    }
  } /**
   * Intersect inheritable attributes.
   *
   * @param {Object} a first attrs object
   * @param {Object} b second attrs object
   *
   * @return {Object} intersected attrs object
   */
  
  function intersectInheritableAttrs(a, b) {
    var c = {};
  
    for (const [name, value] of Object.entries(a)) {
      if (
        // eslint-disable-next-line no-prototype-builtins
        b.hasOwnProperty(name) &&
        inheritableAttrs.includes(name) &&
        value === b[name]
      ) {
        c[name] = value;
      }
    }
  
    if (!Object.keys(c).length) return false;
  
    return c;
  }
  