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diff --git a/browser/components/newtab/lib/RecommendationProvider.sys.mjs b/browser/components/newtab/lib/RecommendationProvider.sys.mjs
new file mode 100644
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+++ b/browser/components/newtab/lib/RecommendationProvider.sys.mjs
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+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+const lazy = {};
+ChromeUtils.defineESModuleGetters(lazy, {
+  PersistentCache: "resource://activity-stream/lib/PersistentCache.sys.mjs",
+  PersonalityProvider:
+    "resource://activity-stream/lib/PersonalityProvider/PersonalityProvider.sys.mjs",
+});
+
+import {
+  actionTypes as at,
+  actionCreators as ac,
+} from "resource://activity-stream/common/Actions.sys.mjs";
+
+const CACHE_KEY = "personalization";
+const PREF_PERSONALIZATION_MODEL_KEYS =
+  "discoverystream.personalization.modelKeys";
+const PREF_USER_TOPSTORIES = "feeds.section.topstories";
+const PREF_SYSTEM_TOPSTORIES = "feeds.system.topstories";
+const PREF_PERSONALIZATION = "discoverystream.personalization.enabled";
+const MIN_PERSONALIZATION_UPDATE_TIME = 12 * 60 * 60 * 1000; // 12 hours
+const PREF_PERSONALIZATION_OVERRIDE =
+  "discoverystream.personalization.override";
+
+// The main purpose of this class is to handle interactions with the recommendation provider.
+// A recommendation provider scores a list of stories, currently this is a personality provider.
+// So all calls to the provider, anything involved with the setup of the provider,
+// accessing prefs for the provider, or updaing devtools with provider state, is contained in here.
+export class RecommendationProvider {
+  constructor() {
+    // Persistent cache for remote endpoint data.
+    this.cache = new lazy.PersistentCache(CACHE_KEY, true);
+  }
+
+  async setProvider(isStartup = false, scores) {
+    // A provider is already set. This can happen when new stories come in
+    // and we need to update their scores.
+    // We can use the existing one, a fresh one is created after startup.
+    // Using the existing one might be a bit out of date,
+    // but it's fine for now. We can rely on restarts for updates.
+    // See bug 1629931 for improvements to this.
+    if (!this.provider) {
+      this.provider = new lazy.PersonalityProvider(this.modelKeys);
+      this.provider.setScores(scores);
+    }
+
+    if (this.provider && this.provider.init) {
+      await this.provider.init();
+      this.store.dispatch(
+        ac.BroadcastToContent({
+          type: at.DISCOVERY_STREAM_PERSONALIZATION_INIT,
+          meta: {
+            isStartup,
+          },
+        })
+      );
+    }
+  }
+
+  async enable(isStartup) {
+    await this.loadPersonalizationScoresCache(isStartup);
+    Services.obs.addObserver(this, "idle-daily");
+    this.loaded = true;
+    this.store.dispatch(
+      ac.BroadcastToContent({
+        type: at.DISCOVERY_STREAM_PERSONALIZATION_UPDATED,
+        meta: {
+          isStartup,
+        },
+      })
+    );
+  }
+
+  get showStories() {
+    // Combine user-set stories opt-out with Mozilla-set config
+    return (
+      this.store.getState().Prefs.values[PREF_SYSTEM_TOPSTORIES] &&
+      this.store.getState().Prefs.values[PREF_USER_TOPSTORIES]
+    );
+  }
+
+  get personalized() {
+    // If stories are not displayed, no point in trying to personalize them.
+    if (!this.showStories) {
+      return false;
+    }
+    const spocsPersonalized =
+      this.store.getState().Prefs.values?.pocketConfig?.spocsPersonalized;
+    const recsPersonalized =
+      this.store.getState().Prefs.values?.pocketConfig?.recsPersonalized;
+    const personalization =
+      this.store.getState().Prefs.values[PREF_PERSONALIZATION];
+
+    // There is a server sent flag to keep personalization on.
+    // If the server stops sending this, we turn personalization off,
+    // until the server starts returning the signal.
+    const overrideState =
+      this.store.getState().Prefs.values[PREF_PERSONALIZATION_OVERRIDE];
+
+    return (
+      personalization &&
+      !overrideState &&
+      (spocsPersonalized || recsPersonalized)
+    );
+  }
+
+  get modelKeys() {
+    if (!this._modelKeys) {
+      this._modelKeys =
+        this.store.getState().Prefs.values[PREF_PERSONALIZATION_MODEL_KEYS];
+    }
+
+    return this._modelKeys;
+  }
+
+  /*
+   * This creates a new recommendationProvider using fresh data,
+   * It's run on a last updated timer. This is the opposite of loadPersonalizationScoresCache.
+   * This is also much slower so we only trigger this in the background on idle-daily.
+   * It causes new profiles to pick up personalization slowly because the first time
+   * a new profile is run you don't have any old cache to use, so it needs to wait for the first
+   * idle-daily. Older profiles can rely on cache during the idle-daily gap. Idle-daily is
+   * usually run once every 24 hours.
+   */
+  async updatePersonalizationScores() {
+    if (
+      !this.personalized ||
+      Date.now() - this.personalizationLastUpdated <
+        MIN_PERSONALIZATION_UPDATE_TIME
+    ) {
+      return;
+    }
+
+    await this.setProvider();
+
+    const personalization = { scores: this.provider.getScores() };
+    this.personalizationLastUpdated = Date.now();
+
+    this.store.dispatch(
+      ac.BroadcastToContent({
+        type: at.DISCOVERY_STREAM_PERSONALIZATION_LAST_UPDATED,
+        data: {
+          lastUpdated: this.personalizationLastUpdated,
+        },
+      })
+    );
+    personalization._timestamp = this.personalizationLastUpdated;
+    this.cache.set("personalization", personalization);
+  }
+
+  /*
+   * This just re hydrates the provider from cache.
+   * We can call this on startup because it's generally fast.
+   * It reports to devtools the last time the data in the cache was updated.
+   */
+  async loadPersonalizationScoresCache(isStartup = false) {
+    const cachedData = (await this.cache.get()) || {};
+    const { personalization } = cachedData;
+
+    if (this.personalized && personalization?.scores) {
+      await this.setProvider(isStartup, personalization.scores);
+
+      this.personalizationLastUpdated = personalization._timestamp;
+
+      this.store.dispatch(
+        ac.BroadcastToContent({
+          type: at.DISCOVERY_STREAM_PERSONALIZATION_LAST_UPDATED,
+          data: {
+            lastUpdated: this.personalizationLastUpdated,
+          },
+          meta: {
+            isStartup,
+          },
+        })
+      );
+    }
+  }
+
+  // This turns personalization on/off if the server sends the override command.
+  // The server sends a true signal to keep personalization on. So a malfunctioning
+  // server would more likely mistakenly turn off personalization, and not turn it on.
+  // This is safer, because the override is for cases where personalization is causing issues.
+  // So having it mistakenly go off is safe, but it mistakenly going on could be bad.
+  personalizationOverride(overrideCommand) {
+    // Are we currently in an override state.
+    // This is useful to know if we want to do a cleanup.
+    const overrideState =
+      this.store.getState().Prefs.values[PREF_PERSONALIZATION_OVERRIDE];
+
+    // Is this profile currently set to be personalized.
+    const personalization =
+      this.store.getState().Prefs.values[PREF_PERSONALIZATION];
+
+    // If we have an override command, profile is currently personalized,
+    // and is not currently being overridden, we can set the override pref.
+    if (overrideCommand && personalization && !overrideState) {
+      this.store.dispatch(ac.SetPref(PREF_PERSONALIZATION_OVERRIDE, true));
+    }
+
+    // This is if we need to revert an override and do cleanup.
+    // We do this if we are in an override state,
+    // but not currently receiving the override signal.
+    if (!overrideCommand && overrideState) {
+      this.store.dispatch({
+        type: at.CLEAR_PREF,
+        data: { name: PREF_PERSONALIZATION_OVERRIDE },
+      });
+    }
+  }
+
+  async calculateItemRelevanceScore(item) {
+    if (this.provider) {
+      const scoreResult = await this.provider.calculateItemRelevanceScore(item);
+      if (scoreResult === 0 || scoreResult) {
+        item.score = scoreResult;
+      }
+    }
+  }
+
+  teardown() {
+    if (this.provider && this.provider.teardown) {
+      // This removes any in memory listeners if available.
+      this.provider.teardown();
+    }
+    if (this.loaded) {
+      Services.obs.removeObserver(this, "idle-daily");
+    }
+    this.loaded = false;
+  }
+
+  async resetState() {
+    this._modelKeys = null;
+    this.personalizationLastUpdated = null;
+    this.provider = null;
+    await this.cache.set("personalization", {});
+    this.store.dispatch(
+      ac.OnlyToMain({
+        type: at.DISCOVERY_STREAM_PERSONALIZATION_RESET,
+      })
+    );
+  }
+
+  async observe(subject, topic, data) {
+    switch (topic) {
+      case "idle-daily":
+        await this.updatePersonalizationScores();
+        this.store.dispatch(
+          ac.BroadcastToContent({
+            type: at.DISCOVERY_STREAM_PERSONALIZATION_UPDATED,
+          })
+        );
+        break;
+    }
+  }
+
+  async onAction(action) {
+    switch (action.type) {
+      case at.INIT:
+        await this.enable(true /* isStartup */);
+        break;
+      case at.DISCOVERY_STREAM_CONFIG_CHANGE:
+        this.teardown();
+        await this.resetState();
+        await this.enable();
+        break;
+      case at.DISCOVERY_STREAM_DEV_IDLE_DAILY:
+        Services.obs.notifyObservers(null, "idle-daily");
+        break;
+      case at.PREF_CHANGED:
+        switch (action.data.name) {
+          case PREF_PERSONALIZATION_MODEL_KEYS:
+            this.store.dispatch(
+              ac.BroadcastToContent({
+                type: at.DISCOVERY_STREAM_CONFIG_RESET,
+              })
+            );
+            break;
+        }
+        break;
+      case at.DISCOVERY_STREAM_PERSONALIZATION_TOGGLE:
+        let enabled = this.store.getState().Prefs.values[PREF_PERSONALIZATION];
+        this.store.dispatch(ac.SetPref(PREF_PERSONALIZATION, !enabled));
+        break;
+      case at.DISCOVERY_STREAM_PERSONALIZATION_OVERRIDE:
+        this.personalizationOverride(action.data.override);
+        break;
+    }
+  }
+}