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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
const lazy = {};
ChromeUtils.defineESModuleGetters(lazy, {
ASRouter: "resource:///modules/asrouter/ASRouter.sys.mjs",
ASRouterTargeting: "resource:///modules/asrouter/ASRouterTargeting.sys.mjs",
});
export const AWScreenUtils = {
/**
* Filter the given screens in place with a predicate.
*
* @param {object[]} screens - The screens to filter.
* @param {Function} callback - The predicate for filtering the screens.
*/
async removeScreens(screens, callback) {
for (let i = 0; i < screens?.length; i++) {
if (await callback(screens[i], i)) {
screens.splice(i--, 1);
}
}
},
/**
* Given a JEXL expression, returns the evaluation of the expression or returns
* true if the expression did not evaluate successfully. This is also used for
* attribute targeting for the checklist feature.
*
* @param {string} targeting - The JEXL expression that will be evaluated
* @returns {boolean}
*/
async evaluateScreenTargeting(targeting) {
const result = await lazy.ASRouter.evaluateExpression({
expression: targeting,
context: lazy.ASRouterTargeting.Environment,
});
if (result?.evaluationStatus?.success) {
return result.evaluationStatus.result;
}
return true;
},
/**
* Filter out screens whose targeting do not match.
*
* Given an array of screens, each screen will have it's `targeting` property
* evaluated, and removed if it's targeting evaluates to false
*
* @param {object[]} screens - An array of screens that will be looped
* through to be evaluated for removal
* @returns {object[]} - A new array containing the screens that were not removed
*/
async evaluateTargetingAndRemoveScreens(screens) {
const filteredScreens = [...screens];
await this.removeScreens(filteredScreens, async screen => {
if (screen.targeting === undefined) {
// Don't remove the screen if we don't have a targeting property
return false;
}
const result = await this.evaluateScreenTargeting(screen.targeting);
// Flipping the value because a true evaluation means we
// don't want to remove the screen, while false means we do
return !result;
});
return filteredScreens;
},
async addScreenImpression(screen) {
await lazy.ASRouter.addScreenImpression(screen);
},
};