1 files changed, 105 insertions, 0 deletions
diff --git a/services/cloudsync/CloudSyncBookmarksFolderCache.jsm b/services/cloudsync/CloudSyncBookmarksFolderCache.jsm
new file mode 100644
index 0000000000..f3c3fc8f24
--- /dev/null
+++ b/services/cloudsync/CloudSyncBookmarksFolderCache.jsm
@@ -0,0 +1,105 @@
+/* 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";
+
+this.EXPORTED_SYMBOLS = ["FolderCache"];
+
+// Cache for bookmarks folder heirarchy.
+var FolderCache = function () {
+  this.cache = new Map();
+}
+
+FolderCache.prototype = {
+  has: function (id) {
+    return this.cache.has(id);
+  },
+
+  insert: function (id, parentId) {
+    if (this.cache.has(id)) {
+      return;
+    }
+
+    if (parentId && !(this.cache.has(parentId))) {
+      throw new Error("insert :: parentId not found in cache: " + parentId);
+    }
+
+    this.cache.set(id, {
+      parent: parentId || null,
+      children: new Set(),
+    });
+
+    if (parentId) {
+      this.cache.get(parentId).children.add(id);
+    }
+  },
+
+  remove: function (id) {
+    if (!(this.cache.has(id))) {
+      throw new Error("remote :: id not found in cache: " + id);
+    }
+
+    let parentId = this.cache.get(id).parent;
+    if (parentId) {
+      this.cache.get(parentId).children.delete(id);
+    }
+
+    for (let child of this.cache.get(id).children) {
+      this.cache.get(child).parent = null;
+    }
+
+    this.cache.delete(id);
+  },
+
+  setParent: function (id, parentId) {
+    if (!(this.cache.has(id))) {
+      throw new Error("setParent :: id not found in cache: " + id);
+    }
+
+    if (parentId && !(this.cache.has(parentId))) {
+      throw new Error("setParent :: parentId not found in cache: " + parentId);
+    }
+
+    let oldParent = this.cache.get(id).parent;
+    if (oldParent) {
+      this.cache.get(oldParent).children.delete(id);
+    }
+    this.cache.get(id).parent = parentId;
+    this.cache.get(parentId).children.add(id);
+
+    return true;
+  },
+
+  getParent: function (id) {
+    if (this.cache.has(id)) {
+      return this.cache.get(id).parent;
+    }
+
+    throw new Error("getParent :: id not found in cache: " + id);
+  },
+
+  getChildren: function (id) {
+    if (this.cache.has(id)) {
+      return this.cache.get(id).children;
+    }
+
+    throw new Error("getChildren :: id not found in cache: " + id);
+  },
+
+  setChildren: function (id, children) {
+    for (let child of children) {
+      if (!this.cache.has(child)) {
+        this.insert(child, id);
+      } else {
+        this.setParent(child, id);
+      }
+    }
+  },
+
+  dump: function () {
+    dump("FolderCache: " + JSON.stringify(this.cache) + "\n");
+  },
+};
+
+this.FolderCache = FolderCache;