CurrentNavigation/src/services/CurrentNavigationCore.ts

import { ICurrentNavigationItem, ICurrentNavigationTerm } from './CurrentNavigationTypes';

export const CurrentNavigationProperties = {
  root: 'CurrentNavigation.Root',
  hidden: 'CurrentNavigation.Hidden',
  simpleLinkUrl: '_Sys_Nav_SimpleLinkUrl',
  targetUrl: '_Sys_Nav_TargetUrl'
};

export function getLocalProperty(term: ICurrentNavigationTerm, name: string): string {
  const properties: { [key: string]: any } = term && term.LocalCustomProperties || {}; // tslint:disable-line:no-any
  const value: any = properties[name]; // tslint:disable-line:no-any
  return value === undefined || value === null ? '' : String(value).trim();
}

export function parseBoolean(value: any): boolean { // tslint:disable-line:no-any
  if (value === true || value === 1) { return true; }
  const normalized: string = String(value || '').trim().toLowerCase();
  return normalized === 'true' || normalized === '1' || normalized === 'yes' || normalized === 'ja';
}

export function resolveTermUrl(term: ICurrentNavigationTerm, siteCollectionUrl: string): string | undefined {
  const raw: string = getLocalProperty(term, CurrentNavigationProperties.simpleLinkUrl)
    || getLocalProperty(term, CurrentNavigationProperties.targetUrl);
  if (!raw || /[\u0000-\u001f\u007f]/.test(raw)) { return undefined; }
  const resolved: string = raw.toLowerCase().indexOf('~sitecollection') === 0
    ? String(siteCollectionUrl || '').replace(/\/+$/, '') + raw.substring('~sitecollection'.length)
    : raw;
  const protocol: RegExpMatchArray = resolved.match(/^([a-z][a-z0-9+.-]*):/i);
  if (protocol && protocol[1].toLowerCase() !== 'http' && protocol[1].toLowerCase() !== 'https') {
    return undefined;
  }
  return resolved;
}

export function normalizeNavigationPath(value: string): string {
  let path: string = String(value || '').trim().toLowerCase();
  path = path.replace(/^https?:\/\/[^/]+/i, '').split('#')[0].split('?')[0].replace(/\/+$/, '');
  try { path = decodeURIComponent(path); } catch (error) { /* Keep malformed URLs comparable as supplied. */ }
  return path || '/';
}

export function normalizeRootWebPath(value: string): string {
  let path: string = normalizeNavigationPath(value);
  path = path.replace(/\/(?:sitepages|pages)\/.*\.aspx$/i, '');
  path = path.replace(/\/(?:default|home)\.aspx$/i, '');
  return path || '/';
}

export function selectCurrentNavigationRoot(
  terms: ICurrentNavigationTerm[],
  currentWebUrl: string,
  siteCollectionUrl: string
): ICurrentNavigationTerm | undefined {
  const webPath: string = normalizeNavigationPath(currentWebUrl);
  const hierarchyRoot: ICurrentNavigationTerm = selectRootByTermHierarchy(
    terms, webPath, siteCollectionUrl
  );
  if (hierarchyRoot) { return hierarchyRoot; }

  let selected: ICurrentNavigationTerm | undefined;
  let selectedScore: number = -1;
  for (let i: number = 0; i < terms.length; i++) {
    if (!parseBoolean(getLocalProperty(terms[i], CurrentNavigationProperties.root))) { continue; }
    const url: string = resolveTermUrl(terms[i], siteCollectionUrl);
    if (!url) { continue; }
    const candidatePath: string = normalizeRootWebPath(url);
    let score: number = -1;
    if (candidatePath === webPath) {
      score = 30000 + candidatePath.length;
    } else if (isDescendantPath(webPath, candidatePath)) {
      score = 20000 + candidatePath.length;
    }
    if (score > selectedScore) { selected = terms[i]; selectedScore = score; }
  }
  return selected;
}

function selectRootByTermHierarchy(
  terms: ICurrentNavigationTerm[],
  webPath: string,
  siteCollectionUrl: string
): ICurrentNavigationTerm | undefined {
  let selected: ICurrentNavigationTerm | undefined;
  let selectedDepth: number = -1;
  for (let i: number = 0; i < terms.length; i++) {
    const termUrl: string = resolveTermUrl(terms[i], siteCollectionUrl);
    if (!termUrl || normalizeRootWebPath(termUrl) !== webPath) { continue; }
    const currentPath: string = String(terms[i].PathOfTerm || '').toLowerCase();
    for (let j: number = 0; j < terms.length; j++) {
      if (!parseBoolean(getLocalProperty(terms[j], CurrentNavigationProperties.root))) { continue; }
      const rootPath: string = String(terms[j].PathOfTerm || '').toLowerCase();
      const isAncestor: boolean = currentPath === rootPath || currentPath.indexOf(rootPath + ';') === 0;
      const rootDepth: number = pathDepth(rootPath);
      if (isAncestor && rootDepth > selectedDepth) {
        selected = terms[j];
        selectedDepth = rootDepth;
      }
    }
  }
  return selected;
}

function isDescendantPath(path: string, parentPath: string): boolean {
  return parentPath === '/' ? path !== '/' : path.indexOf(parentPath + '/') === 0;
}

export function buildCurrentNavigationItems(
  terms: ICurrentNavigationTerm[],
  root: ICurrentNavigationTerm,
  siteCollectionUrl: string,
  languageLcid: number,
  maxDepth: number,
  showRoot: boolean
): ICurrentNavigationItem[] {
  const rootPath: string = String(root.PathOfTerm || '');
  const rootDepth: number = pathDepth(rootPath);
  const hiddenPaths: string[] = terms.filter((term: ICurrentNavigationTerm): boolean =>
    parseBoolean(getLocalProperty(term, CurrentNavigationProperties.hidden))
  ).map((term: ICurrentNavigationTerm): string => String(term.PathOfTerm || '').toLowerCase());
  const candidates: ICurrentNavigationTerm[] = terms.filter((term: ICurrentNavigationTerm): boolean => {
    const path: string = String(term.PathOfTerm || '');
    const isRoot: boolean = term.Id.toLowerCase() === root.Id.toLowerCase();
    const isDescendant: boolean = path.toLowerCase().indexOf(rootPath.toLowerCase() + ';') === 0;
    if ((!showRoot && isRoot) || (!isRoot && !isDescendant)) { return false; }
    const relativeDepth: number = pathDepth(path) - rootDepth + (showRoot ? 1 : 0);
    if (relativeDepth < 1 || relativeDepth > maxDepth) { return false; }
    const lowerPath: string = path.toLowerCase();
    for (let i: number = 0; i < hiddenPaths.length; i++) {
      if (lowerPath === hiddenPaths[i] || lowerPath.indexOf(hiddenPaths[i] + ';') === 0) { return false; }
    }
    return true;
  });
  candidates.sort((a: ICurrentNavigationTerm, b: ICurrentNavigationTerm): number => {
    const depthDifference: number = pathDepth(a.PathOfTerm) - pathDepth(b.PathOfTerm);
    return depthDifference || compareTerms(a, b);
  });
  const byPath: { [path: string]: ICurrentNavigationItem } = {};
  const result: ICurrentNavigationItem[] = [];
  for (let i: number = 0; i < candidates.length; i++) {
    const term: ICurrentNavigationTerm = candidates[i];
    const item: ICurrentNavigationItem = {
      id: cleanGuid(term.Id), label: localizedLabel(term, languageLcid),
      url: resolveTermUrl(term, siteCollectionUrl), items: []
    };
    byPath[String(term.PathOfTerm || '').toLowerCase()] = item;
    const parent: ICurrentNavigationItem = byPath[getParentPath(term.PathOfTerm).toLowerCase()];
    if (parent) { parent.items.push(item); } else { result.push(item); }
  }
  return result;
}

export function cleanGuid(value: string): string {
  const match: RegExpMatchArray = String(value || '').match(/[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}/i);
  return match ? match[0] : String(value || '');
}

function localizedLabel(term: ICurrentNavigationTerm, languageLcid: number): string {
  const labels = term.Labels && term.Labels._Child_Items_ ? term.Labels._Child_Items_ : [];
  let fallback: string = term.Name || '';
  for (let i: number = 0; i < labels.length; i++) {
    if (Number(labels[i].Language) === languageLcid && labels[i].Value) { return labels[i].Value; }
    if (labels[i].IsDefaultForLanguage && labels[i].Value) { fallback = labels[i].Value; }
  }
  return fallback;
}

function pathDepth(path: string): number { return path ? path.split(';').length : 1; }
function getParentPath(path: string): string {
  const parts: string[] = String(path || '').split(';'); parts.pop(); return parts.join(';');
}
function compareTerms(a: ICurrentNavigationTerm, b: ICurrentNavigationTerm): number {
  const ai: number = typeof a.CustomSortOrderIndex === 'number' ? a.CustomSortOrderIndex : -1;
  const bi: number = typeof b.CustomSortOrderIndex === 'number' ? b.CustomSortOrderIndex : -1;
  if (ai >= 0 || bi >= 0) { if (ai < 0) { return 1; } if (bi < 0) { return -1; } return ai - bi; }
  const ap: string = String(a.PathOfTerm || '').toLowerCase();
  const bp: string = String(b.PathOfTerm || '').toLowerCase();
  return ap < bp ? -1 : (ap > bp ? 1 : 0);
}