wcs-microdata.js

import '../microtesia.js/lib/microtesia.js'
import { dedupeMixin } from '@open-wc/dedupe-mixin'

export const MicrodataMixin = dedupeMixin(
  base =>
    class extends base {

      connectedCallback() {
        if (super.connectedCallback) super.connectedCallback()
        this.__updateMicrodata()
      }

      performUpdate() {
        this.__updateMicrodata()
        if (super.performUpdate) super.performUpdate()
      }

      __updateMicrodata() {
        function filterProperty(property, value) {
          if ((property === Array || property.type === Array) && !Array.isArray(value)) {
            return [value]
          } else {
            return value
          }
        }

        const microdata = parseMicrodata(this)[0]

        for (const name in microdata) {
          const value = microdata[name]
          const property = this.constructor.properties[name]

          if (property) {
            this[name] = filterProperty(property, value)
          }
        }
      }

    }

)