1 files changed, 98 insertions, 0 deletions
diff --git a/browser/extensions/pictureinpicture/lib/picture_in_picture_overrides.js b/browser/extensions/pictureinpicture/lib/picture_in_picture_overrides.js
new file mode 100644
index 0000000000..829f33e15b
--- /dev/null
+++ b/browser/extensions/pictureinpicture/lib/picture_in_picture_overrides.js
@@ -0,0 +1,98 @@
+/* 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/. */
+
+"use strict";
+
+/* globals browser, module */
+
+/**
+ * Picture-in-Picture Overrides
+ */
+class PictureInPictureOverrides {
+  /**
+   * Class constructor
+   * @param {Object} availableOverrides Contains all overrides provided in data/picture_in_picture_overrides.js
+   */
+  constructor(availableOverrides) {
+    this.pref = "enable_picture_in_picture_overrides";
+    this._prefEnabledOverrides = new Set();
+    this._availableOverrides = availableOverrides;
+    this.policies = browser.pictureInPictureChild.getPolicies();
+  }
+
+  /**
+   * Ensures the "enable_picture_in_picture_overrides" pref is set; if it is undefined, sets the pref to true
+   */
+  async _checkGlobalPref() {
+    await browser.aboutConfigPipPrefs.getPref(this.pref).then(value => {
+      if (value === false) {
+        this._enabled = false;
+      } else {
+        if (value === undefined) {
+          browser.aboutConfigPipPrefs.setPref(this.pref, true);
+        }
+        this._enabled = true;
+      }
+    });
+  }
+
+  /**
+   * Checks the status of a specified override, and updates the set, `this._prefEnabledOverrides`, accordingly
+   * @param {String} id the id of the specific override contained in `this._availableOverrides`
+   * @param {String} pref the specific preference to check, in the form `disabled_picture_in_picture_overrides.${id}`
+   */
+  async _checkSpecificOverridePref(id, pref) {
+    const isDisabled = await browser.aboutConfigPipPrefs.getPref(pref);
+    if (isDisabled === true) {
+      this._prefEnabledOverrides.delete(id);
+    } else {
+      this._prefEnabledOverrides.add(id);
+    }
+  }
+
+  /**
+   * The function that `run.js` calls to begin checking for changes to the PiP overrides
+   */
+  bootup() {
+    const checkGlobal = async () => {
+      await this._checkGlobalPref();
+      this._onAvailableOverridesChanged();
+    };
+    browser.aboutConfigPipPrefs.onPrefChange.addListener(
+      checkGlobal,
+      this.pref
+    );
+
+    const bootupPrefCheckPromises = [this._checkGlobalPref()];
+
+    for (const id of Object.keys(this._availableOverrides)) {
+      const pref = `disabled_picture_in_picture_overrides.${id}`;
+      const checkSingle = async () => {
+        await this._checkSpecificOverridePref(id, pref);
+        this._onAvailableOverridesChanged();
+      };
+      browser.aboutConfigPipPrefs.onPrefChange.addListener(checkSingle, pref);
+      bootupPrefCheckPromises.push(this._checkSpecificOverridePref(id, pref));
+    }
+
+    Promise.all(bootupPrefCheckPromises).then(() => {
+      this._onAvailableOverridesChanged();
+    });
+  }
+
+  /**
+   * Sets pictureInPictureParent's overrides
+   */
+  async _onAvailableOverridesChanged() {
+    const policies = await this.policies;
+    let enabledOverrides = {};
+    for (const [id, override] of Object.entries(this._availableOverrides)) {
+      const enabled = this._enabled && this._prefEnabledOverrides.has(id);
+      for (const [url, policy] of Object.entries(override)) {
+        enabledOverrides[url] = enabled ? policy : policies.DEFAULT;
+      }
+    }
+    browser.pictureInPictureParent.setOverrides(enabledOverrides);
+  }
+}