1 files changed, 81 insertions, 0 deletions
diff --git a/devtools/server/actors/accessibility/simulator.js b/devtools/server/actors/accessibility/simulator.js
new file mode 100644
index 0000000000..4f7e059d8c
--- /dev/null
+++ b/devtools/server/actors/accessibility/simulator.js
@@ -0,0 +1,81 @@
+/* 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";
+
+const { Actor } = require("resource://devtools/shared/protocol.js");
+const {
+  simulatorSpec,
+} = require("resource://devtools/shared/specs/accessibility.js");
+
+const {
+  simulation: { COLOR_TRANSFORMATION_MATRICES },
+} = require("resource://devtools/server/actors/accessibility/constants.js");
+
+/**
+ * The SimulatorActor is responsible for setting color matrices
+ * based on the simulation type specified.
+ */
+class SimulatorActor extends Actor {
+  constructor(conn, targetActor) {
+    super(conn, simulatorSpec);
+    this.targetActor = targetActor;
+  }
+
+  /**
+   * Simulates a type of visual impairment (i.e. color blindness or contrast loss).
+   *
+   * @param  {Object} options
+   *         Properties: {Array} types
+   *                     Contains the types of visual impairment(s) to be simulated.
+   *                     Set default color matrix if array is empty.
+   * @return {Boolean}
+   *         True if matrix was successfully applied, false otherwise.
+   */
+  simulate(options) {
+    if (options.types.length > 1) {
+      return false;
+    }
+
+    return this.setColorMatrix(
+      COLOR_TRANSFORMATION_MATRICES[
+        options.types.length === 1 ? options.types[0] : "NONE"
+      ]
+    );
+  }
+
+  setColorMatrix(colorMatrix) {
+    if (!this.docShell) {
+      return false;
+    }
+
+    try {
+      this.docShell.setColorMatrix(colorMatrix);
+    } catch (error) {
+      return false;
+    }
+
+    return true;
+  }
+
+  /**
+   * Disables all simulations by setting the default color matrix.
+   */
+  disable() {
+    this.simulate({ types: [] });
+  }
+
+  destroy() {
+    super.destroy();
+
+    this.disable();
+    this.targetActor = null;
+  }
+
+  get docShell() {
+    return this.targetActor && this.targetActor.docShell;
+  }
+}
+
+exports.SimulatorActor = SimulatorActor;