/**
 * Build the filetree
 * @param {HTMLElement} parent Root element of the filetree
 * @param {{name: string, is_dir: boolean, children: any[]}} data FileNode
 * @param {string} location Current location, used for links creation
 */
const buildFileTree = (parent, data, location) => {
  const ul = document.createElement("ul");
  data.forEach((item) => {
    const li = document.createElement("li");
    li.classList.add(item.is_dir ? "directory" : "file");

    if (item.is_dir) {
      // Directory
      li.textContent = item.name;
      li.classList.add("collapsed");

      // Toggle collapsing on click
      li.addEventListener("click", function (e) {
        if (e.target === li) {
          li.classList.toggle("collapsed");
        }
      });
    } else {
      // File
      const url = window.location.href.split("?")[0];
      const a = document.createElement("a");
      a.text = item.name;
      a.href = `${url}?q=${location}${item.name}`;
      li.appendChild(a);
    }

    ul.appendChild(li);

    if (item.children && item.children.length > 0) {
      buildFileTree(
        li,
        item.children,
        item.is_dir ? location + `${item.name}/` : location
      );
    }
  });

  parent.appendChild(ul);
};

/**
 * Uncollapse elements from the deepest element
 * @param {HTMLLIElement} element Element to uncollapse
 */
const uncollapse = (element) => {
  if (element) {
    element.classList.remove("collapsed");
    uncollapse(element.parentElement.closest("li"));
  }
};

/**
 * Find the deepest opened directory
 * @param {string[]} path Current path we are looking at, init with fullpath
 * @param {NodeListOf<ChildNode>} options Options we have, init with list root
 * @returns
 */
const deepestNodeOpened = (path, options) => {
  // Iterate over possible options
  for (let i = 0; i < options.length; ++i) {
    // If the directory and the current path match
    if (decodeURI(path[0]) === options[i].firstChild.nodeValue) {
      if (path.length === 1) {
        // We found it
        return options[i];
      }

      // Continue the search
      return deepestNodeOpened(
        path.slice(1),
        options[i].querySelector("ul").childNodes
      );
    }
  }
};

window.addEventListener("load", () => {
  // Build the filetree
  const fileTreeElement = document.getElementsByTagName("aside")[0];
  const dataElement = fileTreeElement.getElementsByTagName("span")[0];

  buildFileTree(
    fileTreeElement,
    JSON.parse(dataElement.getAttribute("data-json")).children,
    ""
  );
  dataElement.remove();

  // Open nested openeded directories
  const fullpath = window.location.href.split("?")[1].substring(2);
  const path = fullpath.substring(0, fullpath.lastIndexOf("/"));
  const last_openeded = deepestNodeOpened(
    path.split("/"),
    fileTreeElement.querySelector("ul").childNodes
  );

  uncollapse(last_openeded);
});