responsive highlight button

apps/client/public/locales/en-US/translation.json

@@ -123,6 +123,11 @@
   "page": "page",
   "Page deleted successfully": "Page deleted successfully",
   "Page history": "Page history",
+  "Version history for": "Version history for",
+  "document": "document",
+  "Select version": "Select version",
+  "Close": "Close",
+  "Highlight changes": "Highlight changes",
   "Page import is in progress. Please do not close this tab.": "Page import is in progress. Please do not close this tab.",
   "Pages": "Pages",
   "pages": "pages",

apps/client/src/features/page-history/atoms/history-atoms.ts

@@ -1,4 +1,9 @@
 import { atom } from "jotai";
 
 export const historyAtoms = atom<boolean>(false);
-export const activeHistoryIdAtom = atom<string>('');
+export const activeHistoryIdAtom = atom<string>("");
+export const activeHistoryPrevIdAtom = atom<string>("");
+export const highlightChangesAtom = atom<boolean>(true);
+
+export type DiffCounts = { added: number; deleted: number; total: number };
+export const diffCountsAtom = atom<DiffCounts | null>(null);

apps/client/src/features/page-history/components/css/history-diff.module.css

@@ -0,0 +1,38 @@
+.diffSummary {
+  border: rem(1px) solid
+    light-dark(var(--mantine-color-gray-3), var(--mantine-color-dark-4));
+  border-radius: rem(10px);
+  padding: rem(12px);
+  background: light-dark(
+    var(--mantine-color-gray-0),
+    var(--mantine-color-dark-7)
+  );
+}
+
+:global(.history-diff-added) {
+  background: light-dark(#e1f3f2, #01654a) !important;
+  color: light-dark(#007b69, #cafff7) !important;
+  -webkit-box-decoration-break: clone;
+  box-decoration-break: clone;
+}
+
+:global(.history-diff-deleted) {
+  text-decoration: line-through;
+  color: light-dark(var(--mantine-color-red-7), var(--mantine-color-red-4));
+  background: light-dark(var(--mantine-color-red-0), rgba(255, 0, 0, 0.1));
+  border-radius: rem(2px);
+  padding: 0 rem(2px);
+}
+
+:global(.history-diff-node-added) {
+  outline: rem(2px) solid light-dark(var(--mantine-color-teal-5), var(--mantine-color-teal-7));
+  outline-offset: rem(2px);
+  border-radius: rem(4px);
+}
+
+:global(.history-diff-node-deleted) {
+  opacity: 0.5;
+  outline: rem(2px) dashed light-dark(var(--mantine-color-red-4), var(--mantine-color-red-6));
+  outline-offset: rem(4px);
+  border-radius: rem(4px);
+}

apps/client/src/features/page-history/components/css/history-mobile.module.css

@@ -0,0 +1,69 @@
+.container {
+  display: flex;
+  flex-direction: column;
+  height: calc(100vh - 60px);
+  position: relative;
+  overflow: hidden;
+}
+
+.selectorWrapper {
+  padding: var(--mantine-spacing-sm);
+  border-bottom: rem(1px) solid light-dark(var(--mantine-color-gray-3), var(--mantine-color-dark-4));
+  flex-shrink: 0;
+}
+
+.selector {
+  width: 100%;
+  text-align: left;
+  background-color: light-dark(var(--mantine-color-white), var(--mantine-color-dark-6));
+  padding: var(--mantine-spacing-xs) var(--mantine-spacing-sm);
+  cursor: pointer;
+
+  &:hover {
+    background-color: light-dark(var(--mantine-color-gray-0), var(--mantine-color-dark-5));
+  }
+}
+
+.dropdown {
+  max-height: rem(300px);
+}
+
+.option {
+  padding: var(--mantine-spacing-xs) var(--mantine-spacing-sm);
+
+  &[data-combobox-selected] {
+    background-color: light-dark(var(--mantine-color-gray-1), var(--mantine-color-dark-5));
+  }
+
+  &:hover {
+    background-color: light-dark(var(--mantine-color-gray-1), var(--mantine-color-dark-5));
+  }
+}
+
+.editorArea {
+  flex: 1;
+  min-height: 0;
+}
+
+.editorContent {
+  padding: var(--mantine-spacing-md);
+  padding-bottom: rem(60px);
+}
+
+.actionButtons {
+  padding: var(--mantine-spacing-sm) var(--mantine-spacing-md);
+  padding-bottom: rem(70px);
+  border-top: rem(1px) solid light-dark(var(--mantine-color-gray-3), var(--mantine-color-dark-4));
+  background-color: light-dark(var(--mantine-color-white), var(--mantine-color-dark-7));
+  flex-shrink: 0;
+}
+
+.floatingBar {
+  position: fixed;
+  bottom: var(--mantine-spacing-md);
+  left: 50%;
+  transform: translateX(-50%);
+  z-index: 100;
+  background-color: light-dark(var(--mantine-color-white), var(--mantine-color-dark-6));
+  white-space: nowrap;
+}

apps/client/src/features/page-history/components/history-editor.tsx

@@ -1,36 +1,204 @@
 import "@/features/editor/styles/index.css";
-import React, { useEffect } from "react";
+import "./css/history-diff.module.css";
+import { useEffect } from "react";
 import { EditorContent, useEditor } from "@tiptap/react";
 import { mainExtensions } from "@/features/editor/extensions/extensions";
 import { Title } from "@mantine/core";
-import classes from "./history.module.css";
+import { Decoration, DecorationSet } from "@tiptap/pm/view";
+import historyClasses from "./css/history.module.css";
+import { recreateTransform } from "@docmost/editor-ext";
+import { DOMSerializer, Node } from "@tiptap/pm/model";
+import { ChangeSet, simplifyChanges } from "@tiptap/pm/changeset";
+import { useAtom } from "jotai";
+import {
+  diffCountsAtom,
+  highlightChangesAtom,
+} from "@/features/page-history/atoms/history-atoms";
 
 export interface HistoryEditorProps {
   title: string;
   content: any;
+  previousContent?: any;
 }
 
-export function HistoryEditor({ title, content }: HistoryEditorProps) {
+export function HistoryEditor({
+  title,
+  content,
+  previousContent,
+}: HistoryEditorProps) {
+  const [highlightChanges] = useAtom(highlightChangesAtom);
+  const [, setDiffCounts] = useAtom(diffCountsAtom);
+
   const editor = useEditor({
     extensions: mainExtensions,
     editable: false,
   });
 
   useEffect(() => {
-    if (editor && content) {
+    if (!editor || !content) return;
+
+    let decorationSet = DecorationSet.empty;
+    let addedCount = 0;
+    let deletedCount = 0;
+
+    if (previousContent) {
+      try {
+        const schema = editor.schema;
+        const docOld = Node.fromJSON(schema, previousContent);
+        const docNew = Node.fromJSON(schema, content);
+
+        const tr = recreateTransform(docOld, docNew, {
+          complexSteps: true,
+          wordDiffs: true,
+          simplifyDiff: true,
+        });
+
+        const changeSet = ChangeSet.create(docOld).addSteps(
+          tr.doc,
+          tr.mapping.maps,
+          [],
+        );
+        const changes = simplifyChanges(changeSet.changes, docNew);
+
+        editor.commands.setContent(content);
+
+        const specialNodeTypes = new Set([
+          "image",
+          "attachment",
+          "video",
+          "excalidraw",
+          "drawio",
+          "mermaid",
+          "mathBlock",
+          "mathInline",
+          "table",
+          "details",
+          "callout",
+        ]);
+
+        const decorations: Decoration[] = [];
+        let changeIndex = 0;
+
+        for (const change of changes) {
+          if (change.toB > change.fromB) {
+            changeIndex++;
+            const currentIndex = changeIndex;
+            let foundSpecialNode: { node: Node; pos: number } | null = null;
+            docNew.nodesBetween(change.fromB, change.toB, (node, pos) => {
+              if (specialNodeTypes.has(node.type.name)) {
+                const nodeEnd = pos + node.nodeSize;
+                if (change.fromB <= pos && change.toB >= nodeEnd) {
+                  foundSpecialNode = { node, pos };
+                  return false;
+                }
+              }
+            });
+
+            if (foundSpecialNode) {
+              const nodeEnd =
+                foundSpecialNode.pos + foundSpecialNode.node.nodeSize;
+              decorations.push(
+                Decoration.node(foundSpecialNode.pos, nodeEnd, {
+                  class: "history-diff-node-added",
+                  "data-diff-index": String(currentIndex),
+                }),
+              );
+            } else {
+              decorations.push(
+                Decoration.inline(change.fromB, change.toB, {
+                  class: "history-diff-added",
+                  "data-diff-index": String(currentIndex),
+                }),
+              );
+            }
+            addedCount += 1;
+          }
+          if (change.toA > change.fromA) {
+            changeIndex++;
+            const currentIndex = changeIndex;
+            let foundDeletedNode: { node: Node; pos: number } | null = null;
+            docOld.nodesBetween(change.fromA, change.toA, (node, pos) => {
+              if (specialNodeTypes.has(node.type.name)) {
+                const nodeEnd = pos + node.nodeSize;
+                if (change.fromA <= pos && change.toA >= nodeEnd) {
+                  foundDeletedNode = { node, pos };
+                  return false;
+                }
+              }
+            });
+
+            if (foundDeletedNode) {
+              decorations.push(
+                Decoration.widget(change.fromB, () => {
+                  const wrapper = document.createElement("div");
+                  wrapper.className = "history-diff-node-deleted";
+                  wrapper.setAttribute("data-diff-index", String(currentIndex));
+                  const serializer = DOMSerializer.fromSchema(schema);
+                  const dom = serializer.serializeNode(foundDeletedNode!.node);
+                  wrapper.appendChild(dom);
+                  return wrapper;
+                }),
+              );
+            } else {
+              const deletedText = docOld.textBetween(
+                change.fromA,
+                change.toA,
+                "",
+              );
+              if (deletedText) {
+                decorations.push(
+                  Decoration.widget(change.fromB, () => {
+                    const span = document.createElement("span");
+                    span.className = "history-diff-deleted";
+                    span.setAttribute("data-diff-index", String(currentIndex));
+                    span.textContent = deletedText;
+                    return span;
+                  }),
+                );
+              }
+            }
+            deletedCount += 1;
+          }
+        }
+
+        decorationSet = DecorationSet.create(docNew, decorations);
+      } catch (e) {
+        console.error("History diff failed:", e);
+        editor.commands.setContent(content);
+      }
+    } else {
       editor.commands.setContent(content);
     }
-  }, [title, content, editor]);
+
+    const total = addedCount + deletedCount;
+    // @ts-ignore
+    setDiffCounts({ added: addedCount, deleted: deletedCount, total });
+
+    editor.setOptions({
+      editorProps: {
+        ...editor.options.editorProps,
+        decorations: () =>
+          highlightChanges ? decorationSet : DecorationSet.empty,
+      },
+    });
+  }, [
+    title,
+    content,
+    editor,
+    previousContent,
+    highlightChanges,
+    setDiffCounts,
+  ]);
 
   return (
-    <>
-      <div>
-        <Title order={1}>{title}</Title>
-
-        {editor && (
-          <EditorContent editor={editor} className={classes.historyEditor} />
-        )}
-      </div>
-    </>
+    <div>
+      <Title order={1}>{title}</Title>
+      {editor && (
+        <EditorContent
+          editor={editor}
+          className={historyClasses.historyEditor}
+        />
+      )}
+    </div>
   );
 }

apps/client/src/features/page-history/components/history-item.tsx

@@ -1,20 +1,42 @@
 import { Text, Group, UnstyledButton } from "@mantine/core";
 import { CustomAvatar } from "@/components/ui/custom-avatar.tsx";
 import { formattedDate } from "@/lib/time";
-import classes from "./history.module.css";
+import classes from "./css/history.module.css";
 import clsx from "clsx";
+import { IPageHistory } from "@/features/page-history/types/page.types";
+import { memo, useCallback } from "react";
 
 interface HistoryItemProps {
-  historyItem: any;
-  onSelect: (id: string) => void;
+  historyItem: IPageHistory;
+  index: number;
+  onSelect: (id: string, index: number) => void;
+  onHover?: (id: string, index: number) => void;
+  onHoverEnd?: () => void;
   isActive: boolean;
 }
 
-function HistoryItem({ historyItem, onSelect, isActive }: HistoryItemProps) {
+const HistoryItem = memo(function HistoryItem({
+  historyItem,
+  index,
+  onSelect,
+  onHover,
+  onHoverEnd,
+  isActive,
+}: HistoryItemProps) {
+  const handleClick = useCallback(() => {
+    onSelect(historyItem.id, index);
+  }, [onSelect, historyItem.id, index]);
+
+  const handleMouseEnter = useCallback(() => {
+    onHover?.(historyItem.id, index);
+  }, [onHover, historyItem.id, index]);
+
   return (
     <UnstyledButton
       p="xs"
-      onClick={() => onSelect(historyItem.id)}
+      onClick={handleClick}
+      onMouseEnter={handleMouseEnter}
+      onMouseLeave={onHoverEnd}
       className={clsx(classes.history, { [classes.active]: isActive })}
     >
       <Group wrap="nowrap">
@@ -27,11 +49,11 @@ function HistoryItem({ historyItem, onSelect, isActive }: HistoryItemProps) {
             <Group gap={4} wrap="nowrap">
               <CustomAvatar
                 size="sm"
-                avatarUrl={historyItem.lastUpdatedBy.avatarUrl}
-                name={historyItem.lastUpdatedBy.name}
+                avatarUrl={historyItem.lastUpdatedBy?.avatarUrl}
+                name={historyItem.lastUpdatedBy?.name}
               />
               <Text size="sm" c="dimmed" lineClamp={1}>
-                {historyItem.lastUpdatedBy.name}
+                {historyItem.lastUpdatedBy?.name}
               </Text>
             </Group>
           </div>
@@ -39,6 +61,6 @@ function HistoryItem({ historyItem, onSelect, isActive }: HistoryItemProps) {
       </Group>
     </UnstyledButton>
   );
-}
+});
 
 export default HistoryItem;

apps/client/src/features/page-history/components/history-list.tsx

@@ -1,29 +1,27 @@
 import {
   usePageHistoryListQuery,
-  usePageHistoryQuery,
+  prefetchPageHistory,
 } from "@/features/page-history/queries/page-history-query";
 import HistoryItem from "@/features/page-history/components/history-item";
 import {
   activeHistoryIdAtom,
+  activeHistoryPrevIdAtom,
   historyAtoms,
 } from "@/features/page-history/atoms/history-atoms";
-import { useAtom } from "jotai";
-import { useCallback, useEffect } from "react";
-import { Button, ScrollArea, Group, Divider, Text } from "@mantine/core";
+import { useAtom, useSetAtom } from "jotai";
+import { useCallback, useEffect, useMemo, useRef } from "react";
 import {
-  pageEditorAtom,
-  titleEditorAtom,
-} from "@/features/editor/atoms/editor-atoms";
-import { modals } from "@mantine/modals";
-import { notifications } from "@mantine/notifications";
+  Button,
+  ScrollArea,
+  Group,
+  Divider,
+  Loader,
+  Center,
+} from "@mantine/core";
 import { useTranslation } from "react-i18next";
-import { useSpaceAbility } from "@/features/space/permissions/use-space-ability.ts";
-import { useSpaceQuery } from "@/features/space/queries/space-query.ts";
-import { useParams } from "react-router-dom";
-import {
-  SpaceCaslAction,
-  SpaceCaslSubject,
-} from "@/features/space/permissions/permissions.type.ts";
+import { useHistoryRestore } from "@/features/page-history/hooks";
+
+const PREFETCH_DELAY_MS = 150;
 
 interface Props {
   pageId: string;
@@ -32,62 +30,89 @@ interface Props {
 function HistoryList({ pageId }: Props) {
   const { t } = useTranslation();
   const [activeHistoryId, setActiveHistoryId] = useAtom(activeHistoryIdAtom);
+  const setActiveHistoryPrevId = useSetAtom(activeHistoryPrevIdAtom);
+  const setHistoryModalOpen = useSetAtom(historyAtoms);
+
   const {
-    data: pageHistoryList,
+    data: pageHistoryData,
     isLoading,
     isError,
+    fetchNextPage,
+    hasNextPage,
+    isFetchingNextPage,
   } = usePageHistoryListQuery(pageId);
-  const { data: activeHistoryData } = usePageHistoryQuery(activeHistoryId);
 
-  const [mainEditor] = useAtom(pageEditorAtom);
-  const [mainEditorTitle] = useAtom(titleEditorAtom);
-  const [, setHistoryModalOpen] = useAtom(historyAtoms);
+  const historyItems = useMemo(
+    () => pageHistoryData?.pages.flatMap((page) => page.items) ?? [],
+    [pageHistoryData],
+  );
 
-  const { spaceSlug } = useParams();
-  const { data: space } = useSpaceQuery(spaceSlug);
-  const spaceRules = space?.membership?.permissions;
-  const spaceAbility = useSpaceAbility(spaceRules);
+  const loadMoreRef = useRef<HTMLDivElement>(null);
+  const prefetchTimeoutRef = useRef<ReturnType<typeof setTimeout> | null>(null);
 
-  const confirmModal = () =>
-    modals.openConfirmModal({
-      title: t("Please confirm your action"),
-      children: (
-        <Text size="sm">
-          {t(
-            "Are you sure you want to restore this version? Any changes not versioned will be lost.",
-          )}
-        </Text>
-      ),
-      labels: { confirm: t("Confirm"), cancel: t("Cancel") },
-      onConfirm: handleRestore,
-    });
+  const { canRestore, confirmRestore } = useHistoryRestore();
 
-  const handleRestore = useCallback(() => {
-    if (activeHistoryData) {
-      mainEditorTitle
-        .chain()
-        .clearContent()
-        .setContent(activeHistoryData.title, { emitUpdate: true })
-        .run();
-      mainEditor
-        .chain()
-        .clearContent()
-        .setContent(activeHistoryData.content)
-        .run();
-      setHistoryModalOpen(false);
-      notifications.show({ message: t("Successfully restored") });
+  const clearPrefetchTimeout = useCallback(() => {
+    if (prefetchTimeoutRef.current) {
+      clearTimeout(prefetchTimeoutRef.current);
+      prefetchTimeoutRef.current = null;
     }
-  }, [activeHistoryData]);
+  }, []);
+
+  const handleHover = useCallback(
+    (historyId: string, index: number) => {
+      clearPrefetchTimeout();
+      prefetchTimeoutRef.current = setTimeout(() => {
+        prefetchPageHistory(historyId);
+        const prevId = historyItems[index + 1]?.id;
+        if (prevId) {
+          prefetchPageHistory(prevId);
+        }
+      }, PREFETCH_DELAY_MS);
+    },
+    [clearPrefetchTimeout, historyItems],
+  );
 
   useEffect(() => {
-    if (
-      pageHistoryList &&
-      pageHistoryList.items.length > 0 &&
-      !activeHistoryId
-    ) {
-      setActiveHistoryId(pageHistoryList.items[0].id);
+    return clearPrefetchTimeout;
+  }, [clearPrefetchTimeout]);
+
+  const handleSelect = useCallback(
+    (id: string, index: number) => {
+      setActiveHistoryId(id);
+      setActiveHistoryPrevId(historyItems[index + 1]?.id ?? "");
+    },
+    [historyItems, setActiveHistoryId, setActiveHistoryPrevId],
+  );
+
+  useEffect(() => {
+    if (historyItems.length > 0 && !activeHistoryId) {
+      setActiveHistoryId(historyItems[0].id);
+      setActiveHistoryPrevId(historyItems[1]?.id ?? "");
     }
-  }, [pageHistoryList]);
+  }, [
+    historyItems,
+    activeHistoryId,
+    setActiveHistoryId,
+    setActiveHistoryPrevId,
+  ]);
+
+  useEffect(() => {
+    const sentinel = loadMoreRef.current;
+    if (!sentinel || !hasNextPage) return;
+
+    const observer = new IntersectionObserver(
+      (entries) => {
+        if (entries[0].isIntersecting && !isFetchingNextPage) {
+          fetchNextPage();
+        }
+      },
+      { threshold: 0.1 },
+    );
+
+    observer.observe(sentinel);
+    return () => observer.disconnect();
+  }, [fetchNextPage, hasNextPage, isFetchingNextPage]);
 
   if (isLoading) {
     return <></>;
@@ -97,40 +122,45 @@ function HistoryList({ pageId }: Props) {
     return <div>{t("Error loading page history.")}</div>;
   }
 
-  if (!pageHistoryList || pageHistoryList.items.length === 0) {
+  if (historyItems.length === 0) {
     return <>{t("No page history saved yet.")}</>;
   }
 
   return (
     <div>
       <ScrollArea h={620} w="100%" type="scroll" scrollbarSize={5}>
-        {pageHistoryList &&
-          pageHistoryList.items.map((historyItem, index) => (
-            <HistoryItem
-              key={index}
-              historyItem={historyItem}
-              onSelect={setActiveHistoryId}
-              isActive={historyItem.id === activeHistoryId}
-            />
-          ))}
+        {historyItems.map((historyItem, index) => (
+          <HistoryItem
+            key={historyItem.id}
+            historyItem={historyItem}
+            index={index}
+            onSelect={handleSelect}
+            onHover={handleHover}
+            onHoverEnd={clearPrefetchTimeout}
+            isActive={historyItem.id === activeHistoryId}
+          />
+        ))}
+        {hasNextPage && <div ref={loadMoreRef} style={{ height: 1 }} />}
+        {isFetchingNextPage && (
+          <Center py="sm">
+            <Loader size="sm" />
+          </Center>
+        )}
       </ScrollArea>
 
-      {spaceAbility.cannot(
-        SpaceCaslAction.Manage,
-        SpaceCaslSubject.Page,
-      ) ? null : (
+      {canRestore && (
         <>
           <Divider />
           <Group p="xs" wrap="nowrap">
-            <Button size="compact-md" onClick={confirmModal}>
-              {t("Restore")}
-            </Button>
             <Button
               variant="default"
               size="compact-md"
               onClick={() => setHistoryModalOpen(false)}
             >
-              {t("Cancel")}
+              {t("Close")}
+            </Button>
+            <Button size="compact-md" onClick={confirmRestore}>
+              {t("Restore")}
             </Button>
           </Group>
         </>

apps/client/src/features/page-history/components/history-modal-body.tsx

@@ -1,21 +1,45 @@
-import { ScrollArea } from "@mantine/core";
+import {
+  ActionIcon,
+  Group,
+  Paper,
+  ScrollArea,
+  Switch,
+  Text,
+} from "@mantine/core";
 import HistoryList from "@/features/page-history/components/history-list";
-import classes from "./history.module.css";
-import { useAtom } from "jotai";
-import { activeHistoryIdAtom } from "@/features/page-history/atoms/history-atoms";
+import classes from "./css/history.module.css";
+import { useAtom, useAtomValue } from "jotai";
+import {
+  activeHistoryIdAtom,
+  activeHistoryPrevIdAtom,
+  diffCountsAtom,
+  highlightChangesAtom,
+} from "@/features/page-history/atoms/history-atoms";
 import HistoryView from "@/features/page-history/components/history-view";
-import { useEffect } from "react";
+import { useRef } from "react";
+import { IconChevronUp, IconChevronDown } from "@tabler/icons-react";
+import { useTranslation } from "react-i18next";
+import {
+  useDiffNavigation,
+  useHistoryReset,
+} from "@/features/page-history/hooks";
 
 interface Props {
   pageId: string;
 }
 
 export default function HistoryModalBody({ pageId }: Props) {
-  const [activeHistoryId, setActiveHistoryId] = useAtom(activeHistoryIdAtom);
+  const { t } = useTranslation();
+  const scrollViewportRef = useRef<HTMLDivElement>(null);
 
-  useEffect(() => {
-    setActiveHistoryId("");
-  }, [pageId]);
+  const activeHistoryId = useAtomValue(activeHistoryIdAtom);
+  const activeHistoryPrevId = useAtomValue(activeHistoryPrevIdAtom);
+  const [highlightChanges, setHighlightChanges] = useAtom(highlightChangesAtom);
+  const diffCounts = useAtomValue(diffCountsAtom);
+
+  useHistoryReset(pageId);
+  const { currentChangeIndex, handlePrevChange, handleNextChange } =
+    useDiffNavigation(scrollViewportRef);
 
   return (
     <div className={classes.sidebarFlex}>
@@ -25,11 +49,63 @@ export default function HistoryModalBody({ pageId }: Props) {
         </div>
       </nav>
 
-      <ScrollArea h="650" w="100%" scrollbarSize={5}>
-        <div className={classes.sidebarRightSection}>
-          {activeHistoryId && <HistoryView historyId={activeHistoryId} />}
-        </div>
-      </ScrollArea>
+      <div style={{ position: "relative", flex: 1 }}>
+        <ScrollArea
+          h={650}
+          w="100%"
+          scrollbarSize={5}
+          viewportRef={scrollViewportRef}
+        >
+          <div className={classes.sidebarRightSection}>
+            {activeHistoryId && <HistoryView />}
+          </div>
+        </ScrollArea>
+
+        {activeHistoryId && activeHistoryPrevId && (
+          <Paper
+            shadow="md"
+            radius="xl"
+            px="md"
+            py="xs"
+            style={{
+              position: "absolute",
+              bottom: 16,
+              left: "50%",
+              transform: "translateX(-50%)",
+            }}
+          >
+            <Group gap="md" wrap="nowrap">
+              <Switch
+                label={t("Highlight changes")}
+                checked={highlightChanges}
+                onChange={(e) => setHighlightChanges(e.currentTarget.checked)}
+                styles={{ label: { userSelect: "none", whiteSpace: "nowrap" } }}
+              />
+              {highlightChanges && diffCounts && diffCounts.total > 0 && (
+                <Group gap="xs" wrap="nowrap">
+                  <Text size="sm" c="dimmed" style={{ whiteSpace: "nowrap" }}>
+                    {currentChangeIndex} of {diffCounts.total}
+                  </Text>
+                  <ActionIcon
+                    variant="subtle"
+                    size="sm"
+                    onClick={handlePrevChange}
+                  >
+                    <IconChevronUp size={16} />
+                  </ActionIcon>
+                  <ActionIcon
+                    variant="subtle"
+                    size="sm"
+                    onClick={handleNextChange}
+                  >
+                    <IconChevronDown size={16} />
+                  </ActionIcon>
+                </Group>
+              )}
+            </Group>
+          </Paper>
+        )}
+      </div>
     </div>
   );
 }

apps/client/src/features/page-history/components/history-modal-mobile.tsx

@@ -0,0 +1,208 @@
+import {
+  ActionIcon,
+  Box,
+  Button,
+  Group,
+  Paper,
+  ScrollArea,
+  Select,
+  Switch,
+  Text,
+} from "@mantine/core";
+import { useAtom, useAtomValue, useSetAtom } from "jotai";
+import {
+  activeHistoryIdAtom,
+  activeHistoryPrevIdAtom,
+  diffCountsAtom,
+  highlightChangesAtom,
+  historyAtoms,
+} from "@/features/page-history/atoms/history-atoms";
+import HistoryView from "@/features/page-history/components/history-view";
+import { useCallback, useEffect, useMemo, useRef } from "react";
+import { IconCheck, IconChevronDown, IconChevronUp } from "@tabler/icons-react";
+import { useTranslation } from "react-i18next";
+import { usePageHistoryListQuery } from "@/features/page-history/queries/page-history-query";
+import { formattedDate } from "@/lib/time";
+import {
+  useDiffNavigation,
+  useHistoryReset,
+  useHistoryRestore,
+} from "@/features/page-history/hooks";
+import classes from "./css/history-mobile.module.css";
+
+interface Props {
+  pageId: string;
+  pageTitle?: string;
+}
+
+export default function HistoryModalMobile({ pageId, pageTitle }: Props) {
+  const { t } = useTranslation();
+
+  const [activeHistoryId, setActiveHistoryId] = useAtom(activeHistoryIdAtom);
+  const setActiveHistoryPrevId = useSetAtom(activeHistoryPrevIdAtom);
+  const [highlightChanges, setHighlightChanges] = useAtom(highlightChangesAtom);
+  const diffCounts = useAtomValue(diffCountsAtom);
+  const setHistoryModalOpen = useSetAtom(historyAtoms);
+
+  const scrollViewportRef = useRef<HTMLDivElement>(null);
+  const dropdownViewportRef = useRef<HTMLDivElement>(null);
+
+  const {
+    data: pageHistoryData,
+    isLoading,
+    fetchNextPage,
+    hasNextPage,
+    isFetchingNextPage,
+  } = usePageHistoryListQuery(pageId);
+
+  const historyItems = useMemo(
+    () => pageHistoryData?.pages.flatMap((page) => page.items) ?? [],
+    [pageHistoryData],
+  );
+
+  const selectData = useMemo(
+    () =>
+      historyItems.map((item) => ({
+        value: item.id,
+        label: formattedDate(new Date(item.createdAt)),
+        userName: item.lastUpdatedBy?.name,
+      })),
+    [historyItems],
+  );
+
+  useHistoryReset(pageId);
+  const { canRestore, confirmRestore } = useHistoryRestore();
+  const { currentChangeIndex, handlePrevChange, handleNextChange } =
+    useDiffNavigation(scrollViewportRef);
+
+  useEffect(() => {
+    if (historyItems.length > 0 && !activeHistoryId) {
+      setActiveHistoryId(historyItems[0].id);
+      setActiveHistoryPrevId(historyItems[1]?.id ?? "");
+    }
+  }, [
+    historyItems,
+    activeHistoryId,
+    setActiveHistoryId,
+    setActiveHistoryPrevId,
+  ]);
+
+  const handleDropdownScroll = useCallback(() => {
+    const viewport = dropdownViewportRef.current;
+    if (!viewport || !hasNextPage || isFetchingNextPage) return;
+
+    const { scrollTop, scrollHeight, clientHeight } = viewport;
+    const isNearBottom = scrollTop + clientHeight >= scrollHeight - 50;
+
+    if (isNearBottom) {
+      fetchNextPage();
+    }
+  }, [fetchNextPage, hasNextPage, isFetchingNextPage]);
+
+  const handleSelectVersion = useCallback(
+    (value: string | null) => {
+      if (!value) return;
+      const index = historyItems.findIndex((item) => item.id === value);
+      if (index >= 0) {
+        setActiveHistoryId(value);
+        setActiveHistoryPrevId(historyItems[index + 1]?.id ?? "");
+      }
+    },
+    [historyItems, setActiveHistoryId, setActiveHistoryPrevId],
+  );
+
+  if (isLoading) {
+    return null;
+  }
+
+  return (
+    <Box className={classes.container}>
+      <Box className={classes.selectorWrapper}>
+        <Select
+          data={selectData}
+          value={activeHistoryId}
+          onChange={handleSelectVersion}
+          placeholder={t("Select version")}
+          checkIconPosition="right"
+          maxDropdownHeight={300}
+          renderOption={({ option, checked }) => (
+            <Group justify="space-between" wrap="nowrap" w="100%">
+              <div>
+                <Text size="sm">{option.label}</Text>
+                <Text size="xs" c="dimmed">
+                  {(option as { userName?: string }).userName}
+                </Text>
+              </div>
+              {checked && <IconCheck size={16} />}
+            </Group>
+          )}
+          comboboxProps={{ withinPortal: false }}
+          scrollAreaProps={{
+            viewportRef: dropdownViewportRef,
+            onScrollPositionChange: handleDropdownScroll,
+          }}
+        />
+      </Box>
+
+      <ScrollArea
+        className={classes.editorArea}
+        viewportRef={scrollViewportRef}
+        scrollbarSize={5}
+      >
+        <Box className={classes.editorContent}>
+          {activeHistoryId && <HistoryView />}
+        </Box>
+      </ScrollArea>
+
+      {canRestore && (
+        <Group className={classes.actionButtons} justify="flex-end" gap="sm">
+          <Button variant="default" onClick={() => setHistoryModalOpen(false)}>
+            {t("Close")}
+          </Button>
+          <Button onClick={confirmRestore}>{t("Restore")}</Button>
+        </Group>
+      )}
+
+      {activeHistoryId && (
+        <Paper
+          shadow="sm"
+          radius="xl"
+          px="md"
+          py="xs"
+          className={classes.floatingBar}
+        >
+          <Group gap="sm" wrap="nowrap">
+            <Switch
+              label={t("Highlight changes")}
+              checked={highlightChanges}
+              onChange={(e) => setHighlightChanges(e.currentTarget.checked)}
+              size="sm"
+              styles={{ label: { userSelect: "none", whiteSpace: "nowrap" } }}
+            />
+            {highlightChanges && diffCounts && diffCounts.total > 0 && (
+              <Group gap={4} wrap="nowrap">
+                <Text size="sm" c="dimmed" style={{ whiteSpace: "nowrap" }}>
+                  {currentChangeIndex} of {diffCounts.total}
+                </Text>
+                <ActionIcon
+                  variant="subtle"
+                  size="sm"
+                  onClick={handlePrevChange}
+                >
+                  <IconChevronUp size={16} />
+                </ActionIcon>
+                <ActionIcon
+                  variant="subtle"
+                  size="sm"
+                  onClick={handleNextChange}
+                >
+                  <IconChevronDown size={16} />
+                </ActionIcon>
+              </Group>
+            )}
+          </Group>
+        </Paper>
+      )}
+    </Box>
+  );
+}

apps/client/src/features/page-history/components/history-modal.tsx

@@ -2,21 +2,26 @@ import { Modal, Text } from "@mantine/core";
 import { useAtom } from "jotai";
 import { historyAtoms } from "@/features/page-history/atoms/history-atoms";
 import HistoryModalBody from "@/features/page-history/components/history-modal-body";
+import HistoryModalMobile from "@/features/page-history/components/history-modal-mobile";
 import { useTranslation } from "react-i18next";
+import { useMediaQuery } from "@mantine/hooks";
 
 interface Props {
   pageId: string;
+  pageTitle?: string;
 }
-export default function HistoryModal({ pageId }: Props) {
+
+export default function HistoryModal({ pageId, pageTitle }: Props) {
   const { t } = useTranslation();
   const [isModalOpen, setModalOpen] = useAtom(historyAtoms);
+  const isMobile = useMediaQuery("(max-width: 800px)");
 
-  return (
-    <>
+  if (isMobile) {
+    return (
       <Modal.Root
-        size={1200}
         opened={isModalOpen}
         onClose={() => setModalOpen(false)}
+        fullScreen
       >
         <Modal.Overlay />
         <Modal.Content style={{ overflow: "hidden" }}>
@@ -28,11 +33,37 @@ export default function HistoryModal({ pageId }: Props) {
             </Modal.Title>
             <Modal.CloseButton />
           </Modal.Header>
-          <Modal.Body>
-            <HistoryModalBody pageId={pageId} />
+          <Modal.Body
+            p={0}
+            style={{ height: "calc(100vh - 60px)", overflow: "hidden" }}
+          >
+            <HistoryModalMobile pageId={pageId} pageTitle={pageTitle} />
           </Modal.Body>
         </Modal.Content>
       </Modal.Root>
-    </>
+    );
+  }
+
+  return (
+    <Modal.Root
+      size={1400}
+      opened={isModalOpen}
+      onClose={() => setModalOpen(false)}
+    >
+      <Modal.Overlay />
+      <Modal.Content style={{ overflow: "hidden" }}>
+        <Modal.Header>
+          <Modal.Title>
+            <Text size="md" fw={500}>
+              {t("Page history")}
+            </Text>
+          </Modal.Title>
+          <Modal.CloseButton />
+        </Modal.Header>
+        <Modal.Body>
+          <HistoryModalBody pageId={pageId} />
+        </Modal.Body>
+      </Modal.Content>
+    </Modal.Root>
   );
 }

apps/client/src/features/page-history/components/history-view.tsx

@@ -1,29 +1,44 @@
 import { usePageHistoryQuery } from "@/features/page-history/queries/page-history-query";
 import { HistoryEditor } from "@/features/page-history/components/history-editor";
 import { useTranslation } from "react-i18next";
+import { useAtomValue } from "jotai";
+import {
+  activeHistoryIdAtom,
+  activeHistoryPrevIdAtom,
+} from "@/features/page-history/atoms/history-atoms";
 
-interface HistoryProps {
-  historyId: string;
-}
-
-function HistoryView({ historyId }: HistoryProps) {
+function HistoryView() {
   const { t } = useTranslation();
-  const { data, isLoading, isError } = usePageHistoryQuery(historyId);
+  const historyId = useAtomValue(activeHistoryIdAtom);
+  const prevHistoryId = useAtomValue(activeHistoryPrevIdAtom);
 
-  if (isLoading) {
+  const {
+    data,
+    isLoading: isLoadingCurrent,
+    isError: isErrorCurrent,
+  } = usePageHistoryQuery(historyId);
+  const {
+    data: prevData,
+    isLoading: isLoadingPrev,
+    isError: isErrorPrev,
+  } = usePageHistoryQuery(prevHistoryId);
+
+  if (isLoadingCurrent || isLoadingPrev) {
     return <></>;
   }
 
-  if (isError || !data) {
+  if (isErrorCurrent || !data) {
     return <div>{t("Error fetching page data.")}</div>;
   }
 
   return (
-    data && (
-      <div>
-        <HistoryEditor content={data.content} title={data.title} />
-      </div>
-    )
+    <div>
+      <HistoryEditor
+        content={data.content}
+        title={data.title}
+        previousContent={!isErrorPrev ? prevData?.content : undefined}
+      />
+    </div>
   );
 }
 

apps/client/src/features/page-history/hooks/index.ts

@@ -0,0 +1,3 @@
+export { useDiffNavigation } from "./use-diff-navigation";
+export { useHistoryRestore } from "./use-history-restore";
+export { useHistoryReset } from "./use-history-reset";

apps/client/src/features/page-history/hooks/use-diff-navigation.ts

@@ -0,0 +1,58 @@
+import { useAtomValue } from "jotai";
+import { RefObject, useCallback, useEffect, useState } from "react";
+import { diffCountsAtom } from "@/features/page-history/atoms/history-atoms";
+
+/**
+ * Manages navigation between diff changes in the history view.
+ * Provides prev/next handlers and auto-scrolls to the current change.
+ */
+export function useDiffNavigation(
+  scrollViewportRef: RefObject<HTMLDivElement>,
+) {
+  const diffCounts = useAtomValue(diffCountsAtom);
+  const [currentChangeIndex, setCurrentChangeIndex] = useState(0);
+
+  const scrollToChangeIndex = useCallback(
+    (index: number) => {
+      const viewport = scrollViewportRef.current;
+      if (!viewport || index < 1) return;
+
+      const element = viewport.querySelector(`[data-diff-index="${index}"]`);
+      if (element instanceof HTMLElement) {
+        const elementTop = element.offsetTop;
+        const viewportHeight = viewport.clientHeight;
+        const scrollTarget =
+          elementTop - viewportHeight / 2 + element.offsetHeight / 2;
+        viewport.scrollTo({ top: scrollTarget, behavior: "smooth" });
+      }
+    },
+    [scrollViewportRef],
+  );
+
+  useEffect(() => {
+    if (diffCounts && diffCounts.total > 0) {
+      setCurrentChangeIndex(1);
+      requestAnimationFrame(() => scrollToChangeIndex(1));
+    } else {
+      setCurrentChangeIndex(0);
+    }
+  }, [diffCounts, scrollToChangeIndex]);
+
+  const handlePrevChange = useCallback(() => {
+    if (!diffCounts || diffCounts.total === 0) return;
+    const newIndex =
+      currentChangeIndex <= 1 ? diffCounts.total : currentChangeIndex - 1;
+    setCurrentChangeIndex(newIndex);
+    scrollToChangeIndex(newIndex);
+  }, [diffCounts, currentChangeIndex, scrollToChangeIndex]);
+
+  const handleNextChange = useCallback(() => {
+    if (!diffCounts || diffCounts.total === 0) return;
+    const newIndex =
+      currentChangeIndex >= diffCounts.total ? 1 : currentChangeIndex + 1;
+    setCurrentChangeIndex(newIndex);
+    scrollToChangeIndex(newIndex);
+  }, [diffCounts, currentChangeIndex, scrollToChangeIndex]);
+
+  return { currentChangeIndex, handlePrevChange, handleNextChange };
+}

apps/client/src/features/page-history/hooks/use-history-reset.ts

@@ -0,0 +1,24 @@
+import { useAtom } from "jotai";
+import { useEffect } from "react";
+import {
+  activeHistoryIdAtom,
+  activeHistoryPrevIdAtom,
+  diffCountsAtom,
+} from "@/features/page-history/atoms/history-atoms";
+
+/**
+ * Resets history state when pageId changes.
+ * Clears active selection and diff counts.
+ */
+export function useHistoryReset(pageId: string) {
+  const [, setActiveHistoryId] = useAtom(activeHistoryIdAtom);
+  const [, setActiveHistoryPrevId] = useAtom(activeHistoryPrevIdAtom);
+  const [, setDiffCounts] = useAtom(diffCountsAtom);
+
+  useEffect(() => {
+    setActiveHistoryId("");
+    setActiveHistoryPrevId("");
+    // @ts-ignore
+    setDiffCounts(null);
+  }, [pageId, setActiveHistoryId, setActiveHistoryPrevId, setDiffCounts]);
+}

apps/client/src/features/page-history/hooks/use-history-restore.tsx

@@ -0,0 +1,78 @@
+import { useAtom, useAtomValue, useSetAtom } from "jotai";
+import { useCallback } from "react";
+import { useTranslation } from "react-i18next";
+import { Text } from "@mantine/core";
+import { modals } from "@mantine/modals";
+import { notifications } from "@mantine/notifications";
+import { useParams } from "react-router-dom";
+import {
+  activeHistoryIdAtom,
+  historyAtoms,
+} from "@/features/page-history/atoms/history-atoms";
+import { usePageHistoryQuery } from "@/features/page-history/queries/page-history-query";
+import {
+  pageEditorAtom,
+  titleEditorAtom,
+} from "@/features/editor/atoms/editor-atoms";
+import { useSpaceAbility } from "@/features/space/permissions/use-space-ability";
+import { useSpaceQuery } from "@/features/space/queries/space-query";
+import {
+  SpaceCaslAction,
+  SpaceCaslSubject,
+} from "@/features/space/permissions/permissions.type";
+
+export function useHistoryRestore() {
+  const { t } = useTranslation();
+
+  const activeHistoryId = useAtomValue(activeHistoryIdAtom);
+  const { data: activeHistoryData } = usePageHistoryQuery(activeHistoryId);
+
+  const mainEditor = useAtomValue(pageEditorAtom);
+  const mainEditorTitle = useAtomValue(titleEditorAtom);
+  const setHistoryModalOpen = useSetAtom(historyAtoms);
+
+  const { spaceSlug } = useParams();
+  const { data: space } = useSpaceQuery(spaceSlug);
+  const spaceAbility = useSpaceAbility(space?.membership?.permissions);
+
+  const canRestore = spaceAbility.can(
+    SpaceCaslAction.Manage,
+    SpaceCaslSubject.Page,
+  );
+
+  const handleRestore = useCallback(() => {
+    if (!activeHistoryData) return;
+
+    mainEditorTitle
+      .chain()
+      .clearContent()
+      .setContent(activeHistoryData.title, { emitUpdate: true })
+      .run();
+
+    mainEditor
+      .chain()
+      .clearContent()
+      .setContent(activeHistoryData.content)
+      .run();
+
+    setHistoryModalOpen(false);
+    notifications.show({ message: t("Successfully restored") });
+  }, [activeHistoryData, mainEditor, mainEditorTitle, setHistoryModalOpen, t]);
+
+  const confirmRestore = useCallback(() => {
+    modals.openConfirmModal({
+      title: t("Please confirm your action"),
+      children: (
+        <Text size="sm">
+          {t(
+            "Are you sure you want to restore this version? Any changes not versioned will be lost.",
+          )}
+        </Text>
+      ),
+      labels: { confirm: t("Confirm"), cancel: t("Cancel") },
+      onConfirm: handleRestore,
+    });
+  }, [t, handleRestore]);
+
+  return { canRestore, confirmRestore };
+}

apps/client/src/features/page-history/queries/page-history-query.ts

@@ -1,19 +1,38 @@
-import { useQuery, UseQueryResult } from "@tanstack/react-query";
+import {
+  InfiniteData,
+  useInfiniteQuery,
+  UseInfiniteQueryResult,
+  useQuery,
+  UseQueryResult,
+} from "@tanstack/react-query";
 import {
   getPageHistoryById,
   getPageHistoryList,
 } from "@/features/page-history/services/page-history-service";
 import { IPageHistory } from "@/features/page-history/types/page.types";
 import { IPagination } from "@/lib/types.ts";
+import { queryClient } from "@/main";
+
+const HISTORY_STALE_TIME = 60 * 60 * 1000;
+
+export function prefetchPageHistory(historyId: string) {
+  return queryClient.prefetchQuery({
+    queryKey: ["page-history", historyId],
+    queryFn: () => getPageHistoryById(historyId),
+    staleTime: HISTORY_STALE_TIME,
+  });
+}
 
 export function usePageHistoryListQuery(
   pageId: string,
-): UseQueryResult<IPagination<IPageHistory>, Error> {
-  return useQuery({
+): UseInfiniteQueryResult<InfiniteData<IPagination<IPageHistory>, unknown>> {
+  return useInfiniteQuery({
     queryKey: ["page-history-list", pageId],
-    queryFn: () => getPageHistoryList(pageId),
+    queryFn: ({ pageParam }) => getPageHistoryList(pageId, pageParam),
     enabled: !!pageId,
     gcTime: 0,
+    initialPageParam: undefined,
+    getNextPageParam: (lastPage) => lastPage.meta?.nextCursor ?? undefined,
   });
 }
 
@@ -24,6 +43,6 @@ export function usePageHistoryQuery(
     queryKey: ["page-history", historyId],
     queryFn: () => getPageHistoryById(historyId),
     enabled: !!historyId,
-    staleTime: 10 * 60 * 1000,
+    staleTime: HISTORY_STALE_TIME,
   });
 }

apps/client/src/features/page-history/services/page-history-service.ts

@@ -4,9 +4,11 @@ import { IPagination } from "@/lib/types.ts";
 
 export async function getPageHistoryList(
   pageId: string,
+  cursor?: string,
 ): Promise<IPagination<IPageHistory>> {
   const req = await api.post("/pages/history", {
     pageId,
+    cursor,
   });
   return req.data;
 }

apps/server/src/collaboration/listeners/history.listener.ts

@@ -3,6 +3,7 @@ import { OnEvent } from '@nestjs/event-emitter';
 import { PageHistoryRepo } from '@docmost/db/repos/page/page-history.repo';
 import { Page } from '@docmost/db/types/entity.types';
 import { isDeepStrictEqual } from 'node:util';
+import { EnvironmentService } from '../../integrations/environment/environment.service';
 
 export class UpdatedPageEvent {
   page: Page;
@@ -12,7 +13,10 @@ export class UpdatedPageEvent {
 export class HistoryListener {
   private readonly logger = new Logger(HistoryListener.name);
 
-  constructor(private readonly pageHistoryRepo: PageHistoryRepo) {}
+  constructor(
+    private readonly pageHistoryRepo: PageHistoryRepo,
+    private readonly environmentService: EnvironmentService,
+  ) {}
 
   @OnEvent('collab.page.updated')
   async handleCreatePageHistory(event: UpdatedPageEvent) {
@@ -20,7 +24,9 @@ export class HistoryListener {
 
     const pageCreationTime = new Date(page.createdAt).getTime();
     const currentTime = Date.now();
-    const FIVE_MINUTES = 5 * 60 * 1000;
+    const FIVE_MINUTES = this.environmentService.isDevelopment()
+      ? 60 * 1000
+      : 5 * 60 * 1000;
 
     if (currentTime - pageCreationTime < FIVE_MINUTES) {
       return;

package.json

@@ -60,6 +60,7 @@
     "bytes": "^3.1.2",
     "cross-env": "^7.0.3",
     "date-fns": "^4.1.0",
+    "diff": "8.0.3",
     "dompurify": "^3.2.6",
     "fractional-indexing-jittered": "^1.0.0",
     "highlight.js": "^11.11.1",
@@ -70,6 +71,7 @@
     "marked": "13.0.3",
     "ms": "3.0.0-canary.1",
     "qrcode": "^1.5.4",
+    "rfc6902": "5.1.2",
     "uuid": "^11.1.0",
     "y-indexeddb": "^9.0.12",
     "y-prosemirror": "1.3.7",
@@ -98,6 +100,7 @@
     "overrides": {
       "jsdom": "25.0.1",
       "jsonwebtoken": "9.0.3",
+      "prosemirror-changeset": "2.3.1",
       "y-prosemirror": "1.3.7"
     },
     "neverBuiltDependencies": []

packages/editor-ext/package.json

@@ -8,5 +8,6 @@
   },
   "main": "dist/index.js",
   "module": "./src/index.ts",
-  "types": "dist/index.d.ts"
+  "types": "dist/index.d.ts",
+  "dependencies": {}
 }

packages/editor-ext/src/index.ts

@@ -24,3 +24,4 @@ export * from "./lib/highlight";
 export * from "./lib/heading/heading";
 export * from "./lib/unique-id";
 export * from "./lib/shared-storage";
+export * from "./lib/recreate-transform";

packages/editor-ext/src/lib/docs/changeset.md

@@ -0,0 +1,145 @@
+# prosemirror-changeset
+
+This is a helper module that can turn a sequence of document changes
+into a set of insertions and deletions, for example to display them in
+a change-tracking interface. Such a set can be built up incrementally,
+in order to do such change tracking in a halfway performant way during
+live editing.
+
+This code is licensed under an [MIT
+licence](https://github.com/ProseMirror/prosemirror-changeset/blob/master/LICENSE).
+
+## Programming interface
+
+Insertions and deletions are represented as ‘spans’—ranges in the
+document. The deleted spans refer to the original document, whereas
+the inserted ones point into the current document.
+
+It is possible to associate arbitrary data values with such spans, for
+example to track the user that made the change, the timestamp at which
+it was made, or the step data necessary to invert it again.
+
+### class Change`<Data = any>`
+
+A replaced range with metadata associated with it.
+
+* **`fromA`**`: number`\
+  The start of the range deleted/replaced in the old document.
+
+* **`toA`**`: number`\
+  The end of the range in the old document.
+
+* **`fromB`**`: number`\
+  The start of the range inserted in the new document.
+
+* **`toB`**`: number`\
+  The end of the range in the new document.
+
+* **`deleted`**`: readonly Span[]`\
+  Data associated with the deleted content. The length of these
+  spans adds up to `this.toA - this.fromA`.
+
+* **`inserted`**`: readonly Span[]`\
+  Data associated with the inserted content. Length adds up to
+  `this.toB - this.fromB`.
+
+* `static `**`merge`**`<Data>(x: readonly Change[], y: readonly Change[], combine: fn(dataA: Data, dataB: Data) → Data) → readonly Change[]`\
+  This merges two changesets (the end document of x should be the
+  start document of y) into a single one spanning the start of x to
+  the end of y.
+
+
+### class Span`<Data = any>`
+
+Stores metadata for a part of a change.
+
+* **`length`**`: number`\
+  The length of this span.
+
+* **`data`**`: Data`\
+  The data associated with this span.
+
+
+### class ChangeSet`<Data = any>`
+
+A change set tracks the changes to a document from a given point
+in the past. It condenses a number of step maps down to a flat
+sequence of replacements, and simplifies replacments that
+partially undo themselves by comparing their content.
+
+* **`changes`**`: readonly Change[]`\
+  Replaced regions.
+
+* **`addSteps`**`(newDoc: Node, maps: readonly StepMap[], data: Data | readonly Data[]) → ChangeSet`\
+  Computes a new changeset by adding the given step maps and
+  metadata (either as an array, per-map, or as a single value to be
+  associated with all maps) to the current set. Will not mutate the
+  old set.
+
+  Note that due to simplification that happens after each add,
+  incrementally adding steps might create a different final set
+  than adding all those changes at once, since different document
+  tokens might be matched during simplification depending on the
+  boundaries of the current changed ranges.
+
+* **`startDoc`**`: Node`\
+  The starting document of the change set.
+
+* **`map`**`(f: fn(range: Span) → Data) → ChangeSet`\
+  Map the span's data values in the given set through a function
+  and construct a new set with the resulting data.
+
+* **`changedRange`**`(b: ChangeSet, maps?: readonly StepMap[]) → {from: number, to: number}`\
+  Compare two changesets and return the range in which they are
+  changed, if any. If the document changed between the maps, pass
+  the maps for the steps that changed it as second argument, and
+  make sure the method is called on the old set and passed the new
+  set. The returned positions will be in new document coordinates.
+
+* `static `**`create`**`<Data = any>(doc: Node, combine?: fn(dataA: Data, dataB: Data) → Data = (a, b) => a === b ? a : null as any, tokenEncoder?: TokenEncoder = DefaultEncoder) → ChangeSet`\
+  Create a changeset with the given base object and configuration.
+
+  The `combine` function is used to compare and combine metadata—it
+  should return null when metadata isn't compatible, and a combined
+  version for a merged range when it is.
+
+  When given, a token encoder determines how document tokens are
+  serialized and compared when diffing the content produced by
+  changes. The default is to just compare nodes by name and text
+  by character, ignoring marks and attributes.
+
+
+* **`simplifyChanges`**`(changes: readonly Change[], doc: Node) → Change[]`\
+  Simplifies a set of changes for presentation. This makes the
+  assumption that having both insertions and deletions within a word
+  is confusing, and, when such changes occur without a word boundary
+  between them, they should be expanded to cover the entire set of
+  words (in the new document) they touch. An exception is made for
+  single-character replacements.
+
+
+### interface TokenEncoder`<T>`
+
+A token encoder can be passed when creating a `ChangeSet` in order
+to influence the way the library runs its diffing algorithm. The
+encoder determines how document tokens (such as nodes and
+characters) are encoded and compared.
+
+Note that both the encoding and the comparison may run a lot, and
+doing non-trivial work in these functions could impact
+performance.
+
+* **`encodeCharacter`**`(char: number, marks: readonly Mark[]) → T`\
+  Encode a given character, with the given marks applied.
+
+* **`encodeNodeStart`**`(node: Node) → T`\
+  Encode the start of a node or, if this is a leaf node, the
+  entire node.
+
+* **`encodeNodeEnd`**`(node: Node) → T`\
+  Encode the end token for the given node. It is valid to encode
+  every end token in the same way.
+
+* **`compareTokens`**`(a: T, b: T) → boolean`\
+  Compare the given tokens. Should return true when they count as
+  equal.

packages/editor-ext/src/lib/docs/recreate.md

@@ -0,0 +1,30 @@
+# prosemirror-recreate-transform
+
+> reduced and modified fork of https://gitlab.com/mpapp-public/prosemirror-recreate-steps
+
+This is a non-core module of [ProseMirror](http://prosemirror.net).
+ProseMirror is a well-behaved rich semantic content editor based on
+contentEditable, with support for collaborative editing and custom
+document schemas.
+
+Every change to the document is recorded by ProseMirror as a step.
+This module allows recreating the steps needed to go from document
+A to B should these not be available otherwise. Recreating steps
+can be interesting for example in order to show the changes between
+two document versions without having access to the original steps.
+
+Recreating a `Transform` works this way:
+
+```js
+import { recreateTransform } from "@technik-sde/prosemirror-recreate-transform";
+
+let tr = recreateTransform(
+    startDoc, 
+    endDoc, 
+    {
+        complexSteps: true, // Whether step types other than ReplaceStep are allowed.
+        wordDiffs: false, // Whether diffs in text nodes should cover entire words.
+        simplifyDiffs: true // Whether steps should be merged, where possible
+    }
+);
+```

packages/editor-ext/src/lib/recreate-transform/copy.ts

@@ -0,0 +1,3 @@
+export function copy<T>(value: T): T {
+  return JSON.parse(JSON.stringify(value));
+}

packages/editor-ext/src/lib/recreate-transform/getFromPath.ts

@@ -0,0 +1,17 @@
+import { AnyObject } from "./types";
+
+/**
+ * get target value from json-pointer (e.g. /content/0/content)
+ * @param  {AnyObject} obj  object to resolve path into
+ * @param  {string}    path json-pointer
+ * @return {any} target value
+ */
+export function getFromPath(obj: AnyObject, path: string): any {
+  const pathParts = path.split("/");
+  pathParts.shift(); // remove root-entry
+  while (pathParts.length) {
+    const property = pathParts.shift();
+    obj = obj[property];
+  }
+  return obj;
+}

packages/editor-ext/src/lib/recreate-transform/getReplaceStep.ts

@@ -0,0 +1,29 @@
+import { ReplaceStep } from "@tiptap/pm/transform";
+import { Node } from "@tiptap/pm/model";
+
+export function getReplaceStep(fromDoc: Node, toDoc: Node) {
+  let start = toDoc.content.findDiffStart(fromDoc.content);
+  if (start === null) {
+    return false;
+  }
+
+  // @ts-ignore property access to content
+  let { a: endA, b: endB } = toDoc.content.findDiffEnd(fromDoc.content);
+  const overlap = start - Math.min(endA, endB);
+  if (overlap > 0) {
+    // If there is an overlap, there is some freedom of choice in how to calculate the
+    // start/end boundary. for an inserted/removed slice. We choose the extreme with
+    // the lowest depth value.
+    if (
+      fromDoc.resolve(start - overlap).depth <
+      toDoc.resolve(endA + overlap).depth
+    ) {
+      start -= overlap;
+    } else {
+      endA += overlap;
+      endB += overlap;
+    }
+  }
+
+  return new ReplaceStep(start, endB, toDoc.slice(start, endA));
+}

packages/editor-ext/src/lib/recreate-transform/index.ts

@@ -0,0 +1,4 @@
+// https://gitlab.com/mpapp-public/prosemirror-recreate-steps
+// https://github.com/sueddeutsche/prosemirror-recreate-transform
+export { recreateTransform, RecreateTransform } from "./recreateTransform";
+export type { Options } from "./recreateTransform";

packages/editor-ext/src/lib/recreate-transform/recreateTransform.ts

@@ -0,0 +1,279 @@
+import { Transform } from "@tiptap/pm/transform";
+import { Node, Schema } from "@tiptap/pm/model";
+import { applyPatch, createPatch, Operation } from "rfc6902";
+import { diffWordsWithSpace, diffChars } from "diff";
+import { AnyObject } from "./types";
+import { getReplaceStep } from "./getReplaceStep";
+import { simplifyTransform } from "./simplifyTransform";
+import { removeMarks } from "./removeMarks";
+import { getFromPath } from "./getFromPath";
+import { copy } from "./copy";
+
+export interface Options {
+  complexSteps?: boolean;
+  wordDiffs?: boolean;
+  simplifyDiff?: boolean;
+}
+
+export class RecreateTransform {
+  fromDoc: Node;
+  toDoc: Node;
+  complexSteps: boolean;
+  wordDiffs: boolean;
+  simplifyDiff: boolean;
+  schema: Schema;
+  tr: Transform;
+  /* current working document data, may get updated while recalculating node steps */
+  currentJSON: AnyObject;
+  /* final document as json data */
+  finalJSON: AnyObject;
+  ops: Array<Operation>;
+
+  constructor(fromDoc: Node, toDoc: Node, options: Options = {}) {
+    const o = {
+      complexSteps: true,
+      wordDiffs: false,
+      simplifyDiff: true,
+      ...options,
+    };
+
+    this.fromDoc = fromDoc;
+    this.toDoc = toDoc;
+    this.complexSteps = o.complexSteps; // Whether to return steps other than ReplaceSteps
+    this.wordDiffs = o.wordDiffs; // Whether to make text diffs cover entire words
+    this.simplifyDiff = o.simplifyDiff;
+    this.schema = fromDoc.type.schema;
+    this.tr = new Transform(fromDoc);
+  }
+
+  init() {
+    if (this.complexSteps) {
+      // For First steps: we create versions of the documents without marks as
+      // these will only confuse the diffing mechanism and marks won't cause
+      // any mapping changes anyway.
+      this.currentJSON = removeMarks(this.fromDoc).toJSON();
+      this.finalJSON = removeMarks(this.toDoc).toJSON();
+      this.ops = createPatch(this.currentJSON, this.finalJSON);
+      this.recreateChangeContentSteps();
+      this.recreateChangeMarkSteps();
+    } else {
+      // We don't differentiate between mark changes and other changes.
+      this.currentJSON = this.fromDoc.toJSON();
+      this.finalJSON = this.toDoc.toJSON();
+      this.ops = createPatch(this.currentJSON, this.finalJSON);
+      this.recreateChangeContentSteps();
+    }
+
+    if (this.simplifyDiff) {
+      this.tr = simplifyTransform(this.tr) || this.tr;
+    }
+
+    return this.tr;
+  }
+
+  /** convert json-diff to prosemirror steps */
+  recreateChangeContentSteps() {
+    // First step: find content changing steps.
+    let ops = [];
+    while (this.ops.length) {
+      // get next
+      let op = this.ops.shift();
+      ops.push(op);
+
+      let toDoc;
+      const afterStepJSON = copy(this.currentJSON); // working document receiving patches
+      const pathParts = op.path.split("/");
+
+      // collect operations until we receive a valid document:
+      // apply ops-patches until a valid prosemirror document is retrieved,
+      // then try to create a transformation step or retry with next operation
+      while (toDoc == null) {
+        applyPatch(afterStepJSON, [op]);
+
+        try {
+          toDoc = this.schema.nodeFromJSON(afterStepJSON);
+          toDoc.check();
+        } catch (error) {
+          toDoc = null;
+          if (this.ops.length > 0) {
+            op = this.ops.shift();
+            ops.push(op);
+          } else {
+            throw new Error(`No valid diff possible applying ${op.path}`);
+          }
+        }
+      }
+
+      // apply operation (ignoring afterStepJSON)
+      if (
+        this.complexSteps &&
+        ops.length === 1 &&
+        (pathParts.includes("attrs") || pathParts.includes("type"))
+      ) {
+        // Node markup is changing
+        this.addSetNodeMarkup(); // a lost update is ignored
+        ops = [];
+        // console.log("%cop", logStyle, "- update node", ops);
+      } else if (
+        ops.length === 1 &&
+        op.op === "replace" &&
+        pathParts[pathParts.length - 1] === "text"
+      ) {
+        // Text is being replaced, we apply text diffing to find the smallest possible diffs.
+        this.addReplaceTextSteps(op, afterStepJSON);
+        ops = [];
+        // console.log("%cop", logStyle, "- replace", ops);
+      } else if (this.addReplaceStep(toDoc, afterStepJSON)) {
+        // operations have been applied
+        ops = [];
+        // console.log("%cop", logStyle, "- other", ops);
+      }
+    }
+  }
+
+  /** update node with attrs and marks, may also change type */
+  addSetNodeMarkup() {
+    // first diff in document is supposed to be a node-change (in type and/or attributes)
+    // thus simply find the first change and apply a node change step, then recalculate the diff
+    // after updating the document
+    const fromDoc = this.schema.nodeFromJSON(this.currentJSON);
+    const toDoc = this.schema.nodeFromJSON(this.finalJSON);
+    const start = toDoc.content.findDiffStart(fromDoc.content);
+    // @note start is the same (first) position for current and target document
+    const fromNode = fromDoc.nodeAt(start);
+    const toNode = toDoc.nodeAt(start);
+
+    if (start != null) {
+      // @note this completly updates all attributes in one step, by completely replacing node
+      const nodeType = fromNode.type === toNode.type ? null : toNode.type;
+      try {
+        this.tr.setNodeMarkup(start, nodeType, toNode.attrs, toNode.marks);
+      } catch (e) {
+        // if nodetypes differ, the updated node-type and contents might not be compatible
+        // with schema and requires a replace
+        if (nodeType && e.message.includes("Invalid content")) {
+          // @todo add test-case for this scenario
+          this.tr.replaceWith(start, start + fromNode.nodeSize, toNode);
+        } else {
+          throw e;
+        }
+      }
+      this.currentJSON = removeMarks(this.tr.doc).toJSON();
+      // setting the node markup may have invalidated the following ops, so we calculate them again.
+      this.ops = createPatch(this.currentJSON, this.finalJSON);
+      return true;
+    }
+    return false;
+  }
+
+  recreateChangeMarkSteps() {
+    // Now the documents should be the same, except their marks, so everything should map 1:1.
+    // Second step: Iterate through the toDoc and make sure all marks are the same in tr.doc
+    this.toDoc.descendants((tNode, tPos) => {
+      if (!tNode.isInline) {
+        return true;
+      }
+
+      this.tr.doc.nodesBetween(tPos, tPos + tNode.nodeSize, (fNode, fPos) => {
+        if (!fNode.isInline) {
+          return true;
+        }
+        const from = Math.max(tPos, fPos);
+        const to = Math.min(tPos + tNode.nodeSize, fPos + fNode.nodeSize);
+        fNode.marks.forEach((nodeMark) => {
+          if (!nodeMark.isInSet(tNode.marks)) {
+            this.tr.removeMark(from, to, nodeMark);
+          }
+        });
+        tNode.marks.forEach((nodeMark) => {
+          if (!nodeMark.isInSet(fNode.marks)) {
+            this.tr.addMark(from, to, nodeMark);
+          }
+        });
+      });
+    });
+  }
+
+  /**
+   * retrieve and possibly apply replace-step based from doc changes
+   * From http://prosemirror.net/examples/footnote/
+   */
+  addReplaceStep(toDoc: Node, afterStepJSON: AnyObject) {
+    const fromDoc = this.schema.nodeFromJSON(this.currentJSON);
+    const step = getReplaceStep(fromDoc, toDoc);
+
+    if (!step) {
+      return false;
+    } else if (!this.tr.maybeStep(step).failed) {
+      this.currentJSON = afterStepJSON;
+      return true; // @change previously null
+    }
+
+    throw new Error("No valid step found.");
+  }
+
+  /** retrieve and possibly apply text replace-steps based from doc changes */
+  addReplaceTextSteps(op, afterStepJSON) {
+    // We find the position number of the first character in the string
+    const op1 = { ...op, value: "xx" };
+    const op2 = { ...op, value: "yy" };
+    const afterOP1JSON = copy(this.currentJSON);
+    const afterOP2JSON = copy(this.currentJSON);
+    applyPatch(afterOP1JSON, [op1]);
+    applyPatch(afterOP2JSON, [op2]);
+    const op1Doc = this.schema.nodeFromJSON(afterOP1JSON);
+    const op2Doc = this.schema.nodeFromJSON(afterOP2JSON);
+
+    // get text diffs
+    const finalText = op.value;
+    const currentText = getFromPath(this.currentJSON, op.path);
+    const textDiffs = this.wordDiffs
+      ? diffWordsWithSpace(currentText, finalText)
+      : diffChars(currentText, finalText);
+
+    let offset = op1Doc.content.findDiffStart(op2Doc.content);
+    const marks = op1Doc.resolve(offset + 1).marks();
+
+    while (textDiffs.length) {
+      const diff = textDiffs.shift();
+
+      if (diff.added) {
+        const textNode = this.schema
+          .nodeFromJSON({ type: "text", text: diff.value })
+          .mark(marks);
+
+        if (textDiffs.length && textDiffs[0].removed) {
+          const nextDiff = textDiffs.shift();
+          this.tr.replaceWith(offset, offset + nextDiff.value.length, textNode);
+        } else {
+          this.tr.insert(offset, textNode);
+        }
+        offset += diff.value.length;
+      } else if (diff.removed) {
+        if (textDiffs.length && textDiffs[0].added) {
+          const nextDiff = textDiffs.shift();
+          const textNode = this.schema
+            .nodeFromJSON({ type: "text", text: nextDiff.value })
+            .mark(marks);
+          this.tr.replaceWith(offset, offset + diff.value.length, textNode);
+          offset += nextDiff.value.length;
+        } else {
+          this.tr.delete(offset, offset + diff.value.length);
+        }
+      } else {
+        offset += diff.value.length;
+      }
+    }
+
+    this.currentJSON = afterStepJSON;
+  }
+}
+
+export function recreateTransform(
+  fromDoc: Node,
+  toDoc: Node,
+  options: Options = {},
+): Transform {
+  const recreator = new RecreateTransform(fromDoc, toDoc, options);
+  return recreator.init();
+}

packages/editor-ext/src/lib/recreate-transform/removeMarks.ts

@@ -0,0 +1,8 @@
+import { Transform } from "@tiptap/pm/transform";
+import { Node } from "@tiptap/pm/model";
+
+export function removeMarks(doc: Node) {
+  const tr = new Transform(doc);
+  tr.removeMark(0, doc.nodeSize - 2);
+  return tr.doc;
+}

packages/editor-ext/src/lib/recreate-transform/simplifyTransform.ts

@@ -0,0 +1,30 @@
+import { Transform, ReplaceStep, Step } from "@tiptap/pm/transform";
+import { getReplaceStep } from "./getReplaceStep";
+
+// join adjacent ReplaceSteps
+export function simplifyTransform(tr: Transform) {
+  if (!tr.steps.length) {
+    return undefined;
+  }
+
+  const newTr = new Transform(tr.docs[0]);
+  const oldSteps = tr.steps.slice();
+
+  while (oldSteps.length) {
+    let step = oldSteps.shift();
+    while (oldSteps.length && step.merge(oldSteps[0])) {
+      const addedStep = oldSteps.shift();
+      if (step instanceof ReplaceStep && addedStep instanceof ReplaceStep) {
+        step = getReplaceStep(
+          newTr.doc,
+          addedStep.apply(step.apply(newTr.doc).doc).doc,
+          // @ts-ignore
+        ) as Step<any>;
+      } else {
+        step = step.merge(addedStep);
+      }
+    }
+    newTr.step(step);
+  }
+  return newTr;
+}

packages/editor-ext/src/lib/recreate-transform/types.ts

@@ -0,0 +1,3 @@
+export interface AnyObject {
+    [p: string]: any;
+}

pnpm-lock.yaml

@@ -7,6 +7,7 @@ settings:
 overrides:
   jsdom: 25.0.1
   jsonwebtoken: 9.0.3
+  prosemirror-changeset: 2.3.1
   y-prosemirror: 1.3.7
 
 patchedDependencies:
@@ -141,6 +142,9 @@ importers:
       date-fns:
         specifier: ^4.1.0
         version: 4.1.0
+      diff:
+        specifier: 8.0.3
+        version: 8.0.3
       dompurify:
         specifier: ^3.2.6
         version: 3.2.6
@@ -171,6 +175,9 @@ importers:
       qrcode:
         specifier: ^1.5.4
         version: 1.5.4
+      rfc6902:
+        specifier: 5.1.2
+        version: 5.1.2
       uuid:
         specifier: ^11.1.0
         version: 11.1.0
@@ -6110,6 +6117,10 @@ packages:
     resolution: {integrity: sha512-uIFDxqpRZGZ6ThOk84hEfqWoHx2devRFvpTZcTHur85vImfaxUbTW9Ryh4CpCuDnToOP1CEtXKIgytHBPVff5A==}
     engines: {node: '>=0.3.1'}
 
+  diff@8.0.3:
+    resolution: {integrity: sha512-qejHi7bcSD4hQAZE0tNAawRK1ZtafHDmMTMkrrIGgSLl7hTnQHmKCeB45xAcbfTqK2zowkM3j3bHt/4b/ARbYQ==}
+    engines: {node: '>=0.3.1'}
+
   dijkstrajs@1.0.3:
     resolution: {integrity: sha512-qiSlmBq9+BCdCA/L46dw8Uy93mloxsPSbwnm5yrKn2vMPiy8KyAskTF6zuV/j5BMsmOGZDPs7KjU+mjb670kfA==}
 
@@ -9056,6 +9067,9 @@ packages:
     resolution: {integrity: sha512-g6QUff04oZpHs0eG5p83rFLhHeV00ug/Yf9nZM6fLeUrPguBTkTQOdpAWWspMh55TZfVQDPaN3NQJfbVRAxdIw==}
     engines: {iojs: '>=1.0.0', node: '>=0.10.0'}
 
+  rfc6902@5.1.2:
+    resolution: {integrity: sha512-zxcb+PWlE8PwX0tiKE6zP97THQ8/lHmeiwucRrJ3YFupWEmp25RmFSlB1dNTqjkovwqG4iq+u1gzJMBS3um8mA==}
+
   rfdc@1.3.1:
     resolution: {integrity: sha512-r5a3l5HzYlIC68TpmYKlxWjmOP6wiPJ1vWv2HeLhNsRZMrCkxeqxiHlQ21oXmQ4F3SiryXBHhAD7JZqvOJjFmg==}
 
@@ -16747,6 +16761,8 @@ snapshots:
 
   diff@5.2.0: {}
 
+  diff@8.0.3: {}
+
   dijkstrajs@1.0.3: {}
 
   dingbat-to-unicode@1.0.1: {}
@@ -20318,6 +20334,8 @@ snapshots:
 
   reusify@1.1.0: {}
 
+  rfc6902@5.1.2: {}
+
   rfdc@1.3.1: {}
 
   rimraf@3.0.2: