1 files changed, 176 insertions, 0 deletions
diff --git a/toolkit/components/cookiebanners/CookieBannerParent.sys.mjs b/toolkit/components/cookiebanners/CookieBannerParent.sys.mjs
new file mode 100644
index 0000000000..8c84180d0a
--- /dev/null
+++ b/toolkit/components/cookiebanners/CookieBannerParent.sys.mjs
@@ -0,0 +1,176 @@
+/* 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/. */
+
+import { XPCOMUtils } from "resource://gre/modules/XPCOMUtils.sys.mjs";
+
+const lazy = {};
+
+ChromeUtils.defineESModuleGetters(lazy, {
+  PrivateBrowsingUtils: "resource://gre/modules/PrivateBrowsingUtils.sys.mjs",
+});
+
+XPCOMUtils.defineLazyPreferenceGetter(
+  lazy,
+  "serviceMode",
+  "cookiebanners.service.mode",
+  Ci.nsICookieBannerService.MODE_DISABLED
+);
+XPCOMUtils.defineLazyPreferenceGetter(
+  lazy,
+  "serviceModePBM",
+  "cookiebanners.service.mode.privateBrowsing",
+  Ci.nsICookieBannerService.MODE_DISABLED
+);
+
+export class CookieBannerParent extends JSWindowActorParent {
+  /**
+   * Get the browser associated with this window which is the top level embedder
+   * element. Returns null if the top embedder isn't a browser.
+   */
+  get #browserElement() {
+    let topBC = this.browsingContext.top;
+
+    // Not all embedders are browsers.
+    if (topBC.embedderElementType != "browser") {
+      return null;
+    }
+
+    return topBC.embedderElement;
+  }
+
+  #isPrivateBrowsing() {
+    let browser = this.#browserElement;
+    if (!browser) {
+      return false;
+    }
+    return lazy.PrivateBrowsingUtils.isBrowserPrivate(browser);
+  }
+
+  /**
+   * Dispatches a custom "cookiebannerhandled" event on the chrome window.
+   */
+  #notifyCookieBannerState(eventType) {
+    let chromeWin = this.browsingContext.topChromeWindow;
+    if (!chromeWin) {
+      return;
+    }
+    let windowUtils = chromeWin.windowUtils;
+    if (!windowUtils) {
+      return;
+    }
+    let event = new CustomEvent(eventType, {
+      bubbles: true,
+      cancelable: false,
+      detail: {
+        windowContext: this.manager,
+      },
+    });
+    windowUtils.dispatchEventToChromeOnly(chromeWin, event);
+  }
+
+  async receiveMessage(message) {
+    if (message.name == "CookieBanner::Test-FinishClicking") {
+      Services.obs.notifyObservers(
+        null,
+        "cookie-banner-test-clicking-finish",
+        this.manager.documentPrincipal?.baseDomain
+      );
+      return undefined;
+    }
+
+    // Forwards cookie banner detected signals to frontend consumers.
+    if (message.name == "CookieBanner::DetectedBanner") {
+      this.#notifyCookieBannerState("cookiebannerdetected");
+      return undefined;
+    }
+
+    // Forwards cookie banner handled signals to frontend consumers.
+    if (message.name == "CookieBanner::HandledBanner") {
+      this.#notifyCookieBannerState("cookiebannerhandled");
+      return undefined;
+    }
+
+    if (message.name != "CookieBanner::GetClickRules") {
+      return undefined;
+    }
+
+    // TODO: Bug 1790688: consider moving this logic to the cookie banner service.
+    let mode;
+    let isPrivateBrowsing = this.#isPrivateBrowsing();
+    if (isPrivateBrowsing) {
+      mode = lazy.serviceModePBM;
+    } else {
+      mode = lazy.serviceMode;
+    }
+
+    // Check if we have a site preference of the top-level URI. If so, it
+    // takes precedence over the pref setting.
+    let topBrowsingContext = this.manager.browsingContext.top;
+    let topURI = topBrowsingContext.currentWindowGlobal?.documentURI;
+
+    // We don't need to check the domain preference if the cookie banner
+    // handling was disabled by pref.
+    if (mode != Ci.nsICookieBannerService.MODE_DISABLED && topURI) {
+      try {
+        let perDomainMode = Services.cookieBanners.getDomainPref(
+          topURI,
+          isPrivateBrowsing
+        );
+
+        if (perDomainMode != Ci.nsICookieBannerService.MODE_UNSET) {
+          mode = perDomainMode;
+        }
+      } catch (e) {
+        // getPerSitePref could throw with NS_ERROR_NOT_AVAILABLE if the service
+        // is disabled. We will fallback to global pref setting if any errors
+        // occur.
+        if (e.result == Cr.NS_ERROR_NOT_AVAILABLE) {
+          console.error("The cookie banner handling service is not available");
+        } else {
+          console.error("Fail on getting domain pref:", e);
+        }
+      }
+    }
+
+    // Service is disabled for current context (normal or private browsing),
+    // return empty array.
+    if (mode == Ci.nsICookieBannerService.MODE_DISABLED) {
+      return [];
+    }
+
+    let domain = this.manager.documentPrincipal?.baseDomain;
+
+    if (!domain) {
+      return [];
+    }
+
+    let isTopLevel = !this.manager.browsingContext.parent;
+    let rules = Services.cookieBanners.getClickRulesForDomain(
+      domain,
+      isTopLevel
+    );
+
+    if (!rules.length) {
+      return [];
+    }
+
+    // Determine whether we can fall back to opt-in rules. This includes the
+    // detect-only mode where don't interact with the banner.
+    let modeAllowsOptIn =
+      mode == Ci.nsICookieBannerService.MODE_REJECT_OR_ACCEPT;
+    return rules.map(rule => {
+      let target = rule.optOut;
+
+      if (modeAllowsOptIn && !target) {
+        target = rule.optIn;
+      }
+      return {
+        hide: rule.hide ?? rule.presence,
+        presence: rule.presence,
+        skipPresenceVisibilityCheck: rule.skipPresenceVisibilityCheck,
+        target,
+      };
+    });
+  }
+}