// Collection of functions that are useful but non-specific to any particular files

function getBetweenStrings(data, start_string, end_string) {
  const regex = new RegExp(
    `${escapeRegExp(start_string)}(.*?)${escapeRegExp(end_string)}`,
    "s"
  );
  const match = data.match(regex);
  return match ? match[1] : undefined;
}

function escapeRegExp(string) {
  return string.replace(/[.*+?^${}()|[\]\\]/g, "\\$&");
}

function hexToRgb(hex) {
  var result = /^#?([a-f\d]{2})([a-f\d]{2})([a-f\d]{2})$/i.exec(hex);
  return result
    ? {
        r: parseInt(result[1], 16),
        g: parseInt(result[2], 16),
        b: parseInt(result[3], 16),
      }
    : null;
}

function rgbToHex(r, g, b) {
  return "#" + ((1 << 24) + (r << 16) + (g << 8) + b).toString(16).slice(1);
}

function getCpn() {
  const chars =
    "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-_";
  let result = "";
  for (let i = 16; i > 0; --i)
    result += chars[Math.round(Math.random() * (chars.length - 1))];
  return result;
}

function linkParser(url){
  var regExp = /^.*((youtu.be\/)|(v\/)|(\/u\/\w\/)|(embed\/)|(watch\?))\??v?=?([^#&?]*).*/;
  var match = url.match(regExp);
  return (match&&match[7].length==11)? match[7] : false;
}

module.exports = {
  getBetweenStrings,
  hexToRgb,
  rgbToHex,
  getCpn,
  linkParser,
};