JS Fundamentals: - Legendary Farming

function solve(params) {
  let str = params.split(" ");

  const materials = {};

  const legendaryItems = {
    shards: "Shadowmourne",
    fragments: "Valanyr",
    motes: "Dragonwrath"
  };

  let result = "";

  for (let i = 0; i < str.length; i += 2) {
    let quantity = Number(str[i]);
    let material = str[i + 1].toLowerCase();

    if (!materials.hasOwnProperty(material)) {
      materials[material] = 0;
    }

    materials[material] += quantity;

    if (materials[material] >= 250) {
      result += `${legendaryItems[material]} obtained!\n`;
      materials[material] -= 250;
      break;
    }
  }

  for (let item in legendaryItems) {
    if (!materials.hasOwnProperty(item)) {
      materials[item] = 0;
    }
  }

  const legendaryItemsCollected = Object.entries(materials)
    .filter(item => hasLegendaryItems(legendaryItems, item[0]))
    .sort(
      (a, b) => sortDescending(a[1], b[1]) || sortAlphabetically(a[0], b[0])
    )
    .map(formatText)
    .join("\n");

  const junkItemsCollected = Object.entries(materials)
    .filter(item => !hasLegendaryItems(legendaryItems, item[0]))
    .sort((a, b) => sortAlphabetically(a[0], b[0]))
    .map(formatText)
    .join("\n");

  result += legendaryItemsCollected + "\n" + junkItemsCollected;

  function hasLegendaryItems(items, item) {
    return items.hasOwnProperty(item);
  }

  function formatText(textArr) {
    return `${textArr[0]}: ${textArr[1]}`;
  }

  function sortAlphabetically(a, b) {
    return a.localeCompare(b);
  }

  function sortDescending(a, b) {
    return b - a;
  }

  return result;
}