From db54e444387e5adf2e454cc1af4d51b1c73112d4 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Philipp=20Ku=CC=88hn?= <kontakt@philipp-kuehn.com>
Date: Tue, 27 Oct 2020 12:02:26 +0100
Subject: [PATCH] add ugly customSplitBlock command (WIP)

---
 packages/core/src/plugins/index.ts | 70 +++++++++++++++++++++++++++++-
 1 file changed, 68 insertions(+), 2 deletions(-)

diff --git a/packages/core/src/plugins/index.ts b/packages/core/src/plugins/index.ts
index 3f630521..e36ac40d 100644
--- a/packages/core/src/plugins/index.ts
+++ b/packages/core/src/plugins/index.ts
@@ -1,16 +1,82 @@
 import { keymap } from 'prosemirror-keymap'
-import { baseKeymap } from 'prosemirror-commands'
+import {
+  baseKeymap, chainCommands, newlineInCode, createParagraphNear, liftEmptyBlock, splitBlock,
+} from 'prosemirror-commands'
+import { canSplit } from 'prosemirror-transform'
 import { dropCursor } from 'prosemirror-dropcursor'
 import { gapCursor } from 'prosemirror-gapcursor'
 import { undoInputRule } from 'prosemirror-inputrules'
+import {
+  EditorState, NodeSelection, TextSelection, Transaction,
+} from 'prosemirror-state'
+import { ContentMatch, Fragment } from 'prosemirror-model'
 import editable from './editable'
 import focus from './focus'
 
+function defaultBlockAt(match: ContentMatch) {
+  for (let i = 0; i < match.edgeCount; i + 1) {
+    const { type } = match.edge(i)
+    // @ts-ignore
+    if (type.isTextblock && !type.hasRequiredAttrs()) return type
+  }
+  return null
+}
+
+// eslint-disable-next-line
+function customSplitBlock(state: EditorState, dispatch?: (tr: Transaction) => void) {
+  const { $from, $to } = state.selection
+  if (state.selection instanceof NodeSelection && state.selection.node.isBlock) {
+    if (!$from.parentOffset || !canSplit(state.doc, $from.pos)) return false
+    if (dispatch) dispatch(state.tr.split($from.pos).scrollIntoView())
+    return true
+  }
+
+  if (!$from.parent.isBlock) return false
+
+  if (dispatch) {
+    const atEnd = $to.parentOffset === $to.parent.content.size
+    const { tr } = state
+    if (state.selection instanceof TextSelection) tr.deleteSelection()
+    const deflt = $from.depth === 0 ? null : defaultBlockAt($from.node(-1).contentMatchAt($from.indexAfter(-1)))
+    let types = atEnd && deflt ? [{ type: deflt, attrs: $from.node().attrs }] : null
+    console.log(1, { types })
+    // let types = atEnd && deflt ? [{ type: deflt }] : null
+    // @ts-ignore
+    let can = canSplit(tr.doc, tr.mapping.map($from.pos), 1, types)
+    // @ts-ignore
+    if (!types && !can && canSplit(tr.doc, tr.mapping.map($from.pos), 1, deflt && [{ type: deflt }])) {
+      // @ts-ignore
+      types = [{ type: deflt, attrs: $from.node().attrs }]
+      console.log(2, { types })
+      // types = [{ type: deflt }]
+      can = true
+    }
+    if (can) {
+      // @ts-ignore
+      tr.split(tr.mapping.map($from.pos), 1, types)
+      if (!atEnd && !$from.parentOffset && $from.parent.type !== deflt
+      // @ts-ignore
+          && $from.node(-1).canReplace($from.index(-1), $from.indexAfter(-1), Fragment.from(deflt.create(), $from.parent))) { tr.setNodeMarkup(tr.mapping.map($from.before()), deflt) }
+    }
+    dispatch(tr.scrollIntoView())
+  }
+  return true
+}
+
 export default [
   () => dropCursor(),
   () => gapCursor(),
   () => keymap({ Backspace: undoInputRule }),
-  () => keymap(baseKeymap),
+  () => keymap({
+    ...baseKeymap,
+    Enter: chainCommands(
+      newlineInCode,
+      createParagraphNear,
+      liftEmptyBlock,
+      splitBlock,
+      // customSplitBlock,
+    ),
+  }),
   editable,
   focus,
 ]