feat(API): page content update and retrieval (#1937)

* feat: page content update and retrieval output

* import module

* refactor naming
* support prepend

* rename contentOperation -> operation

* dry

* add yjs utils

apps/server/src/collaboration/collaboration.util.ts

@@ -34,6 +34,7 @@ import {
   Highlight,
   UniqueID,
   addUniqueIdsToDoc,
+  htmlToMarkdown,
 } from '@docmost/editor-ext';
 import { generateText, getSchema, JSONContent } from '@tiptap/core';
 import { generateHTML, generateJSON } from '../common/helpers/prosemirror/html';
@@ -42,6 +43,7 @@ import { generateHTML, generateJSON } from '../common/helpers/prosemirror/html';
 // see:https://github.com/ueberdosis/tiptap/issues/4089
 //import { generateJSON } from '@tiptap/html';
 import { Node, Schema } from '@tiptap/pm/model';
+import * as Y from 'yjs';
 import { Logger } from '@nestjs/common';
 
 export const tiptapExtensions = [
@@ -161,3 +163,37 @@ function stripUnknownNodes(
 
   return json;
 }
+
+export function prosemirrorNodeToYElement(node: any): Y.XmlElement | Y.XmlText {
+  if (node.type === 'text') {
+    const ytext = new Y.XmlText();
+    ytext.insert(0, node.text || '');
+    if (node.marks?.length > 0) {
+      const attrs: Record<string, any> = {};
+      for (const mark of node.marks) {
+        attrs[mark.type] = mark.attrs || true;
+      }
+      ytext.format(0, node.text?.length || 0, attrs);
+    }
+    return ytext;
+  }
+
+  const element = new Y.XmlElement(node.type);
+  if (node.attrs) {
+    for (const [key, value] of Object.entries(node.attrs)) {
+      if (value !== null && value !== undefined) {
+        element.setAttribute(key, value as any);
+      }
+    }
+  }
+  if (node.content?.length > 0) {
+    const children = node.content.map(prosemirrorNodeToYElement);
+    element.insert(0, children);
+  }
+  return element;
+}
+
+export function jsonToMarkdown(tiptapJson: any): string {
+  const html = jsonToHtml(tiptapJson);
+  return htmlToMarkdown(html);
+}