import {katex} from "./dependencies.js";

var raw = String.raw;

function style(href) {
  return new Promise(function(resolve, reject) {
    var link = document.createElement("link");
    link.rel = "stylesheet";
    link.href = href;
    link.onerror = reject;
    link.onload = resolve;
    document.head.appendChild(link);
  });
}

export function tex(require) {
  return Promise.all([
    require(katex.resolve()),
    require.resolve(katex.resolve("dist/katex.min.css")).then(style)
  ]).then(function(values) {
    var katex = values[0], tex = renderer();

    function renderer(options) {
      return function() {
        var root = document.createElement("div");
        katex.render(raw.apply(String, arguments), root, options);
        return root.removeChild(root.firstChild);
      };
    }

    tex.options = renderer;
    tex.block = renderer({displayMode: true});
    return tex;
  });
}