const XLSX = require("xlsx");

/* list of file extensions */
const exts = [ "numbers", "xlsx", "xlsb", "xls" ].join(", ");

module.exports = (eleventyConfig) => {
  eleventyConfig.addDataExtension(exts, {
    /* read file and pass raw Buffer object to parser */
    // highlight-next-line
    encoding: null, read: true,

    /* parser callback */
    parser: (contents) => {
      /* contents is the data stored as a Buffer */
      // highlight-next-line
      const wb = XLSX.read(contents);
      /* generate array of row objects from first worksheet */
      return XLSX.utils.sheet_to_json(wb.Sheets[wb.SheetNames[0]]);
    }
  });
};