"use strict";

/** Coordinate CMap routes, parent contexts and browser-history state. */
export class CmapNavigationController {
  constructor({ navigateToHash, cmapRoute, getEditor, getCurrentMap,
    getParentMap, storage, historyObject = window.history, locationObject = window.location }) {
    this.navigateToHash = navigateToHash;
    this.cmapRoute = cmapRoute;
    this.getEditor = getEditor;
    this.getCurrentMap = getCurrentMap;
    this.getParentMap = getParentMap;
    this.storage = storage;
    this.history = historyObject;
    this.location = locationObject;
  }

  open(slug) {
    return this.navigateToHash(this.cmapRoute(slug));
  }

  openLinked(record) {
    if (!record?.cmapSlug) return false;
    this.rememberContext();
    this.open(record.cmapSlug).catch((error) => console.error(error));
    return true;
  }

  openParent() {
    const source = this.getParentMap();
    if (source?.slug) {
      this.open(source.slug).catch((error) => console.error(error));
      return true;
    }
    const editor = this.getEditor();
    return Boolean(editor?.openParentMap());
  }

  requestTransition(action) {
    return this.storage.requestTransition(action);
  }

  rememberContext() {
    const editor = this.getEditor();
    const current = this.getCurrentMap();
    const root = editor?.activeMapRoot;
    if (!current?.slug || !root) return;
    this.history.replaceState({ ...this.history.state, cmapContext: {
      mapSlug: current.slug,
      rootItemId: Number(root.id)
    } }, "", this.location.href);
  }

  async restoreContext(slug) {
    const context = this.history.state?.cmapContext;
    if (!context || context.mapSlug !== slug) return false;
    const editor = this.getEditor();
    const root = editor?.itemRecord(context.rootItemId);
    if (root?.kind === "submap" && root.separateMap) editor.openSubmapMap(root);
    this.history.replaceState({ ...this.history.state, cmapContext: null }, "", this.location.href);
    return true;
  }
}