From 4e64e6b9eab529be14721fc294d9dac6e8e4846f Mon Sep 17 00:00:00 2001
From: BrianHung <brianhung@berkeley.edu>
Date: Wed, 11 Aug 2021 17:41:57 -0700
Subject: [PATCH] fix y-prosemirror autofocus

---
 src/lib.js                   | 7 ++++---
 src/plugins/cursor-plugin.js | 4 ++--
 src/plugins/sync-plugin.js   | 4 ++--
 3 files changed, 8 insertions(+), 7 deletions(-)

diff --git a/src/lib.js b/src/lib.js
index 812d09a9..7ef9b511 100644
--- a/src/lib.js
+++ b/src/lib.js
@@ -2,6 +2,7 @@ import { updateYFragment} from './plugins/sync-plugin.js' // eslint-disable-line
 import * as Y from 'yjs'
 import { EditorView } from 'prosemirror-view' // eslint-disable-line
 import { Node, Schema } from 'prosemirror-model' // eslint-disable-line
+import { Selection } from 'prosemirror-state' // eslint-disable-line
 import * as error from 'lib0/error.js'
 import * as map from 'lib0/map.js'
 import * as eventloop from 'lib0/eventloop.js'
@@ -47,9 +48,9 @@ export const setMeta = (view, key, value) => {
  * @param {ProsemirrorMapping} mapping
  * @return {any} relative position
  */
-export const absolutePositionToRelativePosition = (pos, type, mapping) => {
-  if (pos === 0) {
-    return Y.createRelativePositionFromTypeIndex(type, 0)
+export const absolutePositionToRelativePosition = (doc, pos, type, mapping) => {
+  if (pos <= Selection.atStart(doc).from) {
+    return Y.createRelativePositionFromTypeIndex(type, 0, -1)
   }
   let n = type._first === null ? null : /** @type {Y.ContentType} */ (type._first.content).type
   while (n !== null && type !== n) {
diff --git a/src/plugins/cursor-plugin.js b/src/plugins/cursor-plugin.js
index ce7bb39e..3a719556 100644
--- a/src/plugins/cursor-plugin.js
+++ b/src/plugins/cursor-plugin.js
@@ -114,11 +114,11 @@ export const yCursorPlugin = (awareness, { cursorBuilder = defaultCursorBuilder,
         /**
          * @type {Y.RelativePosition}
          */
-        const anchor = absolutePositionToRelativePosition(selection.anchor, ystate.type, ystate.binding.mapping)
+        const anchor = absolutePositionToRelativePosition(view.state.doc, selection.anchor, ystate.type, ystate.binding.mapping)
         /**
          * @type {Y.RelativePosition}
          */
-        const head = absolutePositionToRelativePosition(selection.head, ystate.type, ystate.binding.mapping)
+        const head = absolutePositionToRelativePosition(view.state.doc, selection.head, ystate.type, ystate.binding.mapping)
         if (current.cursor == null || !Y.compareRelativePositions(Y.createRelativePositionFromJSON(current.cursor.anchor), anchor) || !Y.compareRelativePositions(Y.createRelativePositionFromJSON(current.cursor.head), head)) {
           awareness.setLocalStateField(cursorStateField, {
             anchor, head
diff --git a/src/plugins/sync-plugin.js b/src/plugins/sync-plugin.js
index 7051bbd5..0a995839 100644
--- a/src/plugins/sync-plugin.js
+++ b/src/plugins/sync-plugin.js
@@ -169,8 +169,8 @@ const restoreRelativeSelection = (tr, relSel, binding) => {
 }
 
 export const getRelativeSelection = (pmbinding, state) => ({
-  anchor: absolutePositionToRelativePosition(state.selection.anchor, pmbinding.type, pmbinding.mapping),
-  head: absolutePositionToRelativePosition(state.selection.head, pmbinding.type, pmbinding.mapping)
+  anchor: absolutePositionToRelativePosition(state.doc, state.selection.anchor, pmbinding.type, pmbinding.mapping),
+  head: absolutePositionToRelativePosition(state.doc, state.selection.head, pmbinding.type, pmbinding.mapping)
 })
 
 /**