import { ajax } from "discourse/lib/ajax";
import { url } from "discourse/lib/computed";
import RestModel from "discourse/models/rest";
import UserAction from "discourse/models/user-action";
import { emojiUnescape } from "discourse/lib/text";

export default RestModel.extend({
  loaded: false,

  _initialize: function() {
    this.setProperties({ itemsLoaded: 0, content: [] });
  }.on("init"),

  filterParam: function() {
    const filter = this.get("filter");
    if (filter === Discourse.UserAction.TYPES.replies) {
      return [UserAction.TYPES.replies, UserAction.TYPES.quotes].join(",");
    }

    if (!filter) {
      return [UserAction.TYPES.topics, UserAction.TYPES.posts].join(",");
    }

    return filter;
  }.property("filter"),

  baseUrl: url(
    "itemsLoaded",
    "user.username_lower",
    "/user_actions.json?offset=%@&username=%@"
  ),

  filterBy(filter, noContentHelpKey) {
    this.setProperties({
      filter,
      itemsLoaded: 0,
      content: [],
      noContentHelpKey: noContentHelpKey,
      lastLoadedUrl: null
    });
    return this.findItems();
  },

  noContent: function() {
    return this.get("loaded") && this.get("content").length === 0;
  }.property("loaded", "content.@each"),

  remove(userAction) {
    // 1) remove the user action from the child groups
    this.get("content").forEach(function(ua) {
      ["likes", "stars", "edits", "bookmarks"].forEach(function(group) {
        const items = ua.get("childGroups." + group + ".items");
        if (items) {
          items.removeObject(userAction);
        }
      });
    });

    // 2) remove the parents that have no children
    const content = this.get("content").filter(function(ua) {
      return ["likes", "stars", "edits", "bookmarks"].any(function(group) {
        return ua.get("childGroups." + group + ".items.length") > 0;
      });
    });

    this.setProperties({ content, itemsLoaded: content.length });
  },

  findItems() {
    const self = this;

    let findUrl = this.get("baseUrl");
    if (this.get("filterParam")) {
      findUrl += "&filter=" + this.get("filterParam");
    }
    if (this.get("noContentHelpKey")) {
      findUrl += "&no_results_help_key=" + this.get("noContentHelpKey");
    }

    // Don't load the same stream twice. We're probably at the end.
    const lastLoadedUrl = this.get("lastLoadedUrl");
    if (lastLoadedUrl === findUrl) {
      return Ember.RSVP.resolve();
    }

    if (this.get("loading")) {
      return Ember.RSVP.resolve();
    }
    this.set("loading", true);
    return ajax(findUrl, { cache: "false" })
      .then(function(result) {
        if (result && result.no_results_help) {
          self.set("noContentHelp", result.no_results_help);
        }
        if (result && result.user_actions) {
          const copy = Em.A();
          result.user_actions.forEach(function(action) {
            action.title = emojiUnescape(
              Handlebars.Utils.escapeExpression(action.title)
            );
            copy.pushObject(UserAction.create(action));
          });

          self.get("content").pushObjects(UserAction.collapseStream(copy));
          self.setProperties({
            itemsLoaded: self.get("itemsLoaded") + result.user_actions.length
          });
        }
      })
      .finally(function() {
        self.set("loaded", true);
        self.set("loading", false);
        self.set("lastLoadedUrl", findUrl);
      });
  }
});