1 files changed, 131 insertions, 0 deletions
diff --git a/devtools/server/actors/layout.js b/devtools/server/actors/layout.js
new file mode 100644
index 000000000..0b9242b5f
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+++ b/devtools/server/actors/layout.js
@@ -0,0 +1,131 @@
+/* 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, ActorClassWithSpec } = require("devtools/shared/protocol");
+const { gridSpec, layoutSpec } = require("devtools/shared/specs/layout");
+const { getStringifiableFragments } = require("devtools/server/actors/utils/css-grid-utils");
+
+/**
+ * Set of actors the expose the CSS layout information to the devtools protocol clients.
+ *
+ * The |Layout| actor is the main entry point. It is used to get various CSS
+ * layout-related information from the document.
+ *
+ * The |Grid| actor provides the grid fragment information to inspect the grid container.
+ */
+
+/**
+ * The GridActor provides information about a given grid's fragment data.
+ */
+var GridActor = ActorClassWithSpec(gridSpec, {
+  /**
+   * @param  {LayoutActor} layoutActor
+   *         The LayoutActor instance.
+   * @param  {DOMNode} containerEl
+   *         The grid container element.
+   */
+  initialize: function (layoutActor, containerEl) {
+    Actor.prototype.initialize.call(this, layoutActor.conn);
+
+    this.containerEl = containerEl;
+    this.walker = layoutActor.walker;
+  },
+
+  destroy: function () {
+    Actor.prototype.destroy.call(this);
+
+    this.containerEl = null;
+    this.gridFragments = null;
+    this.walker = null;
+  },
+
+  form: function (detail) {
+    if (detail === "actorid") {
+      return this.actorID;
+    }
+
+    // Seralize the grid fragment data into JSON so protocol.js knows how to write
+    // and read the data.
+    let gridFragments = this.containerEl.getGridFragments();
+    this.gridFragments = getStringifiableFragments(gridFragments);
+
+    let form = {
+      actor: this.actorID,
+      gridFragments: this.gridFragments
+    };
+
+    return form;
+  },
+});
+
+/**
+ * The CSS layout actor provides layout information for the given document.
+ */
+var LayoutActor = ActorClassWithSpec(layoutSpec, {
+  initialize: function (conn, tabActor, walker) {
+    Actor.prototype.initialize.call(this, conn);
+
+    this.tabActor = tabActor;
+    this.walker = walker;
+  },
+
+  destroy: function () {
+    Actor.prototype.destroy.call(this);
+
+    this.tabActor = null;
+    this.walker = null;
+  },
+
+  /**
+   * Returns an array of GridActor objects for all the grid containers found by iterating
+   * below the given rootNode.
+   *
+   * @param  {Node|NodeActor} rootNode
+   *         The root node to start iterating at.
+   * @return {Array} An array of GridActor objects.
+   */
+  getGrids: function (rootNode) {
+    let grids = [];
+
+    let treeWalker = this.walker.getDocumentWalker(rootNode);
+    while (treeWalker.nextNode()) {
+      let currentNode = treeWalker.currentNode;
+
+      if (currentNode.getGridFragments && currentNode.getGridFragments().length > 0) {
+        let gridActor = new GridActor(this, currentNode);
+        grids.push(gridActor);
+      }
+    }
+
+    return grids;
+  },
+
+  /**
+   * Returns an array of GridActor objects for all existing grid containers found by
+   * iterating below the given rootNode and optionally including nested frames.
+   *
+   * @param  {NodeActor} rootNode
+   * @param  {Boolean} traverseFrames
+   *         Whether or not we should iterate through nested frames.
+   * @return {Array} An array of GridActor objects.
+   */
+  getAllGrids: function (rootNode, traverseFrames) {
+    if (!traverseFrames) {
+      return this.getGridActors(rootNode);
+    }
+
+    let grids = [];
+    for (let {document} of this.tabActor.windows) {
+      grids = [...grids, ...this.getGrids(document.documentElement)];
+    }
+
+    return grids;
+  },
+
+});
+
+exports.GridActor = GridActor;
+exports.LayoutActor = LayoutActor;