/* eslint-env browser */

;(function () {
  try {
    const onMessage = ({ data }) => {
      if (!data.wappalyzer || !data.wappalyzer.technologies) {
        return
      }

      const { technologies } = data.wappalyzer

      const toScalar = (value) =>
        typeof value === 'string' || typeof value === 'number' ? value : !!value

      removeEventListener('message', onMessage)

      postMessage({
        wappalyzer: {
          dom: technologies.reduce((technologies, { name, dom }) => {
            Object.keys(dom).forEach((selector) => {
              let nodes = []

              try {
                nodes = document.querySelectorAll(selector)
              } catch (error) {
                // Continue
              }

              if (!nodes.length) {
                return
              }

              nodes.forEach((node) => {
                dom[selector].forEach(({ properties }) => {
                  if (properties) {
                    Object.keys(properties).forEach((property) => {
                      if (
                        Object.prototype.hasOwnProperty.call(node, property)
                      ) {
                        const value = node[property]

                        if (typeof value !== 'undefined') {
                          technologies.push({
                            name,
                            selector,
                            property,
                            value: toScalar(value),
                          })
                        }
                      }
                    })
                  }
                })
              })
            })

            return technologies
          }, []),
        },
      })
    }

    addEventListener('message', onMessage)
  } catch (e) {
    // Fail quietly
  }
})()