1 files changed, 165 insertions, 0 deletions
diff --git a/browser/extensions/webcompat/lib/injections.js b/browser/extensions/webcompat/lib/injections.js
new file mode 100644
index 0000000000..8760f551c7
--- /dev/null
+++ b/browser/extensions/webcompat/lib/injections.js
@@ -0,0 +1,165 @@
+/* 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 */
+
+class Injections {
+  constructor(availableInjections, customFunctions) {
+    this.INJECTION_PREF = "perform_injections";
+
+    this._injectionsEnabled = true;
+
+    this._availableInjections = availableInjections;
+    this._activeInjections = new Map();
+    this._customFunctions = customFunctions;
+  }
+
+  bindAboutCompatBroker(broker) {
+    this._aboutCompatBroker = broker;
+  }
+
+  bootup() {
+    browser.aboutConfigPrefs.onPrefChange.addListener(() => {
+      this.checkInjectionPref();
+    }, this.INJECTION_PREF);
+    this.checkInjectionPref();
+  }
+
+  checkInjectionPref() {
+    browser.aboutConfigPrefs.getPref(this.INJECTION_PREF).then(value => {
+      if (value === undefined) {
+        browser.aboutConfigPrefs.setPref(this.INJECTION_PREF, true);
+      } else if (value === false) {
+        this.unregisterContentScripts();
+      } else {
+        this.registerContentScripts();
+      }
+    });
+  }
+
+  getAvailableInjections() {
+    return this._availableInjections;
+  }
+
+  isEnabled() {
+    return this._injectionsEnabled;
+  }
+
+  async registerContentScripts() {
+    const platformInfo = await browser.runtime.getPlatformInfo();
+    const platformMatches = [
+      "all",
+      platformInfo.os,
+      platformInfo.os == "android" ? "android" : "desktop",
+    ];
+    for (const injection of this._availableInjections) {
+      if (platformMatches.includes(injection.platform)) {
+        injection.availableOnPlatform = true;
+        await this.enableInjection(injection);
+      }
+    }
+
+    this._injectionsEnabled = true;
+    this._aboutCompatBroker.portsToAboutCompatTabs.broadcast({
+      interventionsChanged: this._aboutCompatBroker.filterOverrides(
+        this._availableInjections
+      ),
+    });
+  }
+
+  assignContentScriptDefaults(contentScripts) {
+    let finalConfig = Object.assign({}, contentScripts);
+
+    if (!finalConfig.runAt) {
+      finalConfig.runAt = "document_start";
+    }
+
+    return finalConfig;
+  }
+
+  async enableInjection(injection) {
+    if (injection.active) {
+      return undefined;
+    }
+
+    if (injection.customFunc) {
+      return this.enableCustomInjection(injection);
+    }
+
+    return this.enableContentScripts(injection);
+  }
+
+  enableCustomInjection(injection) {
+    if (injection.customFunc in this._customFunctions) {
+      this._customFunctions[injection.customFunc](injection);
+      injection.active = true;
+    } else {
+      console.error(
+        `Provided function ${injection.customFunc} wasn't found in functions list`
+      );
+    }
+  }
+
+  async enableContentScripts(injection) {
+    try {
+      const handle = await browser.contentScripts.register(
+        this.assignContentScriptDefaults(injection.contentScripts)
+      );
+      this._activeInjections.set(injection, handle);
+      injection.active = true;
+    } catch (ex) {
+      console.error(
+        "Registering WebCompat GoFaster content scripts failed: ",
+        ex
+      );
+    }
+  }
+
+  unregisterContentScripts() {
+    for (const injection of this._availableInjections) {
+      this.disableInjection(injection);
+    }
+
+    this._injectionsEnabled = false;
+    this._aboutCompatBroker.portsToAboutCompatTabs.broadcast({
+      interventionsChanged: false,
+    });
+  }
+
+  async disableInjection(injection) {
+    if (!injection.active) {
+      return undefined;
+    }
+
+    if (injection.customFunc) {
+      return this.disableCustomInjections(injection);
+    }
+
+    return this.disableContentScripts(injection);
+  }
+
+  disableCustomInjections(injection) {
+    const disableFunc = injection.customFunc + "Disable";
+
+    if (disableFunc in this._customFunctions) {
+      this._customFunctions[disableFunc](injection);
+      injection.active = false;
+    } else {
+      console.error(
+        `Provided function ${disableFunc} for disabling injection wasn't found in functions list`
+      );
+    }
+  }
+
+  async disableContentScripts(injection) {
+    const contentScript = this._activeInjections.get(injection);
+    await contentScript.unregister();
+    this._activeInjections.delete(injection);
+    injection.active = false;
+  }
+}
+
+module.exports = Injections;