module.exports = function (eleventyConfig) {
  eleventyConfig.addPassthroughCopy("css");

  eleventyConfig.addCollection("columns", function (collectionApi) {
    return collectionApi
      .getFilteredByGlob("columns/**/*.md")
      .sort((a, b) => b.date - a.date);
  });

  eleventyConfig.addFilter("year", function (date) {
    return new Date(date).getFullYear();
  });

  eleventyConfig.addFilter("isoDate", function (date) {
    return new Date(date).toISOString().split("T")[0];
  });

  eleventyConfig.addFilter("readableDate", function (date) {
    return new Date(date).toLocaleDateString("en-US", {
      year: "numeric",
      month: "long",
      day: "numeric",
    });
  });

  return {
    dir: {
      input: ".",
      includes: "_includes",
      output: "_site",
    },
    markdownTemplateEngine: "njk",
    htmlTemplateEngine: "njk",
  };
};