From 3edd364c3b40f5fd9e2b339eaea522c9493bf2f8 Mon Sep 17 00:00:00 2001
From: Yanzhen Yu <yanzhen@smartx.com>
Date: Sun, 30 Sep 2018 15:26:00 +0800
Subject: [PATCH] basic rebuild implementation

---
 src/index.ts    | 140 ++----------------------------------------------
 src/rebuild.ts  |  46 ++++++++++++++++
 src/snapshot.ts |  89 ++++++++++++++++++++++++++++++
 src/types.ts    |  55 +++++++++++++++++++
 4 files changed, 193 insertions(+), 137 deletions(-)
 create mode 100644 src/rebuild.ts
 create mode 100644 src/snapshot.ts
 create mode 100644 src/types.ts

diff --git a/src/index.ts b/src/index.ts
index 4a003d2b..758f2df9 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -1,138 +1,4 @@
-let _id = 1;
+import snapshot from './snapshot';
+import rebuild from './rebuild';
 
-function genId(): number {
-  return _id++;
-}
-
-enum NodeType {
-  Document,
-  DocumentType,
-  Element,
-  Text,
-  CDATA,
-  Comment,
-}
-
-type serializedNode =
-  | documentNode
-  | documentTypeNode
-  | elementNode
-  | textNode
-  | cdataNode
-  | commentNode;
-
-type documentNode = {
-  type: NodeType.Document;
-  childNodes: serializedNode[];
-};
-
-type documentTypeNode = {
-  type: NodeType.DocumentType;
-  name: string;
-  publicId: string;
-  systemId: string;
-};
-
-type attributes = {
-  [key: string]: string;
-};
-type elementNode = {
-  type: NodeType.Element;
-  tagName: string;
-  attributes: attributes;
-  childNodes: serializedNode[];
-};
-
-type textNode = {
-  type: NodeType.Text;
-  textContent: string;
-};
-
-type cdataNode = {
-  type: NodeType.CDATA;
-  textContent: '';
-};
-
-type commentNode = {
-  type: NodeType.Comment;
-  textContent: string;
-};
-
-function serializeNode(n: Node): serializedNode | false {
-  switch (n.nodeType) {
-    case n.DOCUMENT_NODE:
-      return {
-        type: NodeType.Document,
-        childNodes: [],
-      };
-    case n.DOCUMENT_TYPE_NODE:
-      return {
-        type: NodeType.DocumentType,
-        name: (n as DocumentType).name,
-        publicId: (n as DocumentType).publicId,
-        systemId: (n as DocumentType).systemId,
-      };
-    case n.ELEMENT_NODE:
-      const tagName = (n as HTMLElement).tagName.toLowerCase();
-      const attributes: attributes = {};
-      for (const { name, value } of Array.from((n as HTMLElement).attributes)) {
-        attributes[name] = value;
-      }
-      return {
-        type: NodeType.Element,
-        tagName,
-        attributes,
-        childNodes: [],
-      };
-    case n.TEXT_NODE:
-      // The parent node may not be a html element which has a tagName attribute.
-      // So just let it be undefined which is ok in this use case.
-      const parentTagName =
-        n.parentNode && (n.parentNode as HTMLElement).tagName;
-      let textContent = (n as Text).textContent;
-      if (parentTagName === 'SCRIPT') {
-        textContent = '';
-      }
-      return {
-        type: NodeType.Text,
-        textContent,
-      };
-    case n.CDATA_SECTION_NODE:
-      return {
-        type: NodeType.CDATA,
-        textContent: '',
-      };
-    case n.COMMENT_NODE:
-      return {
-        type: NodeType.Comment,
-        textContent: (n as Comment).textContent,
-      };
-    default:
-      return false;
-  }
-}
-
-type serializedNodeWithId = serializedNode & { id: number };
-
-function snapshot(n: Node): serializedNodeWithId | null {
-  const _serializedNode = serializeNode(n);
-  if (!_serializedNode) {
-    // TODO: dev only
-    console.warn(n, 'not serialized');
-    return null;
-  }
-  const serializedNode: serializedNodeWithId = Object.assign(_serializedNode, {
-    id: genId(),
-  });
-  if (
-    serializedNode.type === NodeType.Document ||
-    serializedNode.type === NodeType.Element
-  ) {
-    for (const childN of Array.from(n.childNodes)) {
-      serializedNode.childNodes.push(snapshot(childN));
-    }
-  }
-  return serializedNode;
-}
-
-export default snapshot;
+export { snapshot, rebuild };
diff --git a/src/rebuild.ts b/src/rebuild.ts
new file mode 100644
index 00000000..1d581e45
--- /dev/null
+++ b/src/rebuild.ts
@@ -0,0 +1,46 @@
+import { serializedNodeWithId, NodeType } from './types';
+
+function buildNode(n: serializedNodeWithId): Node | null {
+  switch (n.type) {
+    case NodeType.Document:
+      return document.implementation.createDocument(null, '', null);
+    case NodeType.DocumentType:
+      return document.implementation.createDocumentType(
+        n.name,
+        n.publicId,
+        n.systemId,
+      );
+    case NodeType.Element:
+      const node = document.createElement(n.tagName);
+      for (const name in n.attributes) {
+        if (n.attributes.hasOwnProperty(name)) {
+          node.setAttribute(name, n.attributes[name]);
+        }
+      }
+      return node;
+    case NodeType.Text:
+      return document.createTextNode(n.textContent);
+    case NodeType.CDATA:
+      return document.createCDATASection(n.textContent);
+    case NodeType.Comment:
+      return document.createComment(n.textContent);
+    default:
+      return null;
+  }
+}
+
+function rebuild(n: serializedNodeWithId): Node | null {
+  const root = buildNode(n);
+  if (!root) {
+    return null;
+  }
+  if (n.type === NodeType.Document || n.type === NodeType.Element) {
+    for (const childN of n.childNodes) {
+      const childNode = rebuild(childN);
+      root.appendChild(childNode);
+    }
+  }
+  return root;
+}
+
+export default rebuild;
diff --git a/src/snapshot.ts b/src/snapshot.ts
new file mode 100644
index 00000000..ce805da5
--- /dev/null
+++ b/src/snapshot.ts
@@ -0,0 +1,89 @@
+import {
+  serializedNode,
+  serializedNodeWithId,
+  NodeType,
+  attributes,
+} from './types';
+
+let _id = 1;
+
+function genId(): number {
+  return _id++;
+}
+
+function serializeNode(n: Node): serializedNode | false {
+  switch (n.nodeType) {
+    case n.DOCUMENT_NODE:
+      return {
+        type: NodeType.Document,
+        childNodes: [],
+      };
+    case n.DOCUMENT_TYPE_NODE:
+      return {
+        type: NodeType.DocumentType,
+        name: (n as DocumentType).name,
+        publicId: (n as DocumentType).publicId,
+        systemId: (n as DocumentType).systemId,
+      };
+    case n.ELEMENT_NODE:
+      const tagName = (n as HTMLElement).tagName.toLowerCase();
+      const attributes: attributes = {};
+      for (const { name, value } of Array.from((n as HTMLElement).attributes)) {
+        attributes[name] = value;
+      }
+      return {
+        type: NodeType.Element,
+        tagName,
+        attributes,
+        childNodes: [],
+      };
+    case n.TEXT_NODE:
+      // The parent node may not be a html element which has a tagName attribute.
+      // So just let it be undefined which is ok in this use case.
+      const parentTagName =
+        n.parentNode && (n.parentNode as HTMLElement).tagName;
+      let textContent = (n as Text).textContent;
+      if (parentTagName === 'SCRIPT') {
+        textContent = '';
+      }
+      return {
+        type: NodeType.Text,
+        textContent,
+      };
+    case n.CDATA_SECTION_NODE:
+      return {
+        type: NodeType.CDATA,
+        textContent: '',
+      };
+    case n.COMMENT_NODE:
+      return {
+        type: NodeType.Comment,
+        textContent: (n as Comment).textContent,
+      };
+    default:
+      return false;
+  }
+}
+
+function snapshot(n: Node): serializedNodeWithId | null {
+  const _serializedNode = serializeNode(n);
+  if (!_serializedNode) {
+    // TODO: dev only
+    console.warn(n, 'not serialized');
+    return null;
+  }
+  const serializedNode: serializedNodeWithId = Object.assign(_serializedNode, {
+    id: genId(),
+  });
+  if (
+    serializedNode.type === NodeType.Document ||
+    serializedNode.type === NodeType.Element
+  ) {
+    for (const childN of Array.from(n.childNodes)) {
+      serializedNode.childNodes.push(snapshot(childN));
+    }
+  }
+  return serializedNode;
+}
+
+export default snapshot;
diff --git a/src/types.ts b/src/types.ts
new file mode 100644
index 00000000..25fc9962
--- /dev/null
+++ b/src/types.ts
@@ -0,0 +1,55 @@
+export enum NodeType {
+  Document,
+  DocumentType,
+  Element,
+  Text,
+  CDATA,
+  Comment,
+}
+
+export type documentNode = {
+  type: NodeType.Document;
+  childNodes: serializedNodeWithId[];
+};
+
+export type documentTypeNode = {
+  type: NodeType.DocumentType;
+  name: string;
+  publicId: string;
+  systemId: string;
+};
+
+export type attributes = {
+  [key: string]: string;
+};
+export type elementNode = {
+  type: NodeType.Element;
+  tagName: string;
+  attributes: attributes;
+  childNodes: serializedNodeWithId[];
+};
+
+export type textNode = {
+  type: NodeType.Text;
+  textContent: string;
+};
+
+export type cdataNode = {
+  type: NodeType.CDATA;
+  textContent: '';
+};
+
+export type commentNode = {
+  type: NodeType.Comment;
+  textContent: string;
+};
+
+export type serializedNode =
+  | documentNode
+  | documentTypeNode
+  | elementNode
+  | textNode
+  | cdataNode
+  | commentNode;
+
+export type serializedNodeWithId = serializedNode & { id: number };