content: /**
   * SEO component that queries for data with
   *  Gatsby's useStaticQuery React hook
   *
   * See: https://www.gatsbyjs.org/docs/use-static-query/
   */
  
  import React from 'react'
  import PropTypes from 'prop-types'
  import Helmet from 'react-helmet'
  import { useStaticQuery, graphql } from 'gatsby'
  
  function SEO ({ description, lang, meta, title }) {
    const { site } = useStaticQuery(
      graphql`
        query {
          site {
            siteMetadata {
              title
              description
              author
            }
          }
        }
      `
    )
  
    const metaDescription = description || site.siteMetadata.description
  
    return (
      <Helmet
        htmlAttributes={{
          lang
        }}
        title={title}
        titleTemplate={`%s | ${site.siteMetadata.title}`}
        meta={[
          {
            name: 'description',
            content: metaDescription
          },
          {
            property: 'og:title',
            content: title
          },
          {
            property: 'og:description',
            content: metaDescription
          },
          {
            property: 'og:type',
            content: 'website'
          },
          {
            name: 'twitter:card',
            content: 'summary'
          },
          {
            name: 'twitter:creator',
            content: site.siteMetadata.author
          },
          {
            name: 'twitter:title',
            content: title
          },
          {
            name: 'twitter:description',
            content: metaDescription
          }
        ].concat(meta)}
      />
    )
  }
  
  SEO.defaultProps = {
    lang: 'en',
    meta: [],
    description: ''
  }
  
  SEO.propTypes = {
    description: PropTypes.string,
    lang: PropTypes.string,
    meta: PropTypes.arrayOf(PropTypes.object),
    title: PropTypes.string.isRequired
  }
  
  export default SEO
  