From 42ef3a821b1eef1bec167aefba4633f5b8347a8b Mon Sep 17 00:00:00 2001
From: guchigow <lanov64@yandex.kz>
Date: Wed, 18 Dec 2024 18:58:27 +0500
Subject: [PATCH] #4533 - After inserting a nucleotide in the Text-editing
 mode, the cursor blinks in the wrong place

---
 .../src/application/editor/modes/SequenceMode.ts       | 10 ++++++++--
 .../render/renderers/sequence/SequenceRenderer.ts      |  4 ++++
 .../ketcher-core/src/domain/entities/BaseMonomer.ts    |  5 +++++
 3 files changed, 17 insertions(+), 2 deletions(-)

diff --git a/packages/ketcher-core/src/application/editor/modes/SequenceMode.ts b/packages/ketcher-core/src/application/editor/modes/SequenceMode.ts
index afebe22d5c..24ea7d2018 100644
--- a/packages/ketcher-core/src/application/editor/modes/SequenceMode.ts
+++ b/packages/ketcher-core/src/application/editor/modes/SequenceMode.ts
@@ -1040,8 +1040,7 @@ export class SequenceMode extends BaseMode {
     const currentSequence = SequenceRenderer.currentChain;
 
     const currentSequenceHasPhosphate =
-      currentSequence?.lastNonEmptyNode?.monomer?.monomerItem?.props?.Name ===
-      'Phosphate';
+      currentSequence?.lastNonEmptyNode?.monomer?.isPhosphate;
 
     let nextCaretPosition =
       SequenceRenderer.caretPosition + chainsCollection.length;
@@ -1050,6 +1049,13 @@ export class SequenceMode extends BaseMode {
       nextCaretPosition -= 1;
     }
 
+    const hasPhosphateAtChainEnd =
+      chainsCollection?.lastNode?.monomer?.isPhosphate;
+
+    if (!SequenceRenderer.isCaretAtChainEnd && hasPhosphateAtChainEnd) {
+      nextCaretPosition -= 1;
+    }
+
     const modelChanges = this.insertNewSequenceFragment(chainsCollection);
 
     modelChanges.addOperation(new ReinitializeModeOperation());
diff --git a/packages/ketcher-core/src/application/render/renderers/sequence/SequenceRenderer.ts b/packages/ketcher-core/src/application/render/renderers/sequence/SequenceRenderer.ts
index 48f9448f73..02de9ed942 100644
--- a/packages/ketcher-core/src/application/render/renderers/sequence/SequenceRenderer.ts
+++ b/packages/ketcher-core/src/application/render/renderers/sequence/SequenceRenderer.ts
@@ -945,4 +945,8 @@ export class SequenceRenderer {
       SequenceRenderer.chainsCollection.firstNode instanceof EmptySequenceNode
     );
   }
+
+  public static get isCaretAtChainEnd() {
+    return SequenceRenderer.currentEdittingNode instanceof EmptySequenceNode;
+  }
 }
diff --git a/packages/ketcher-core/src/domain/entities/BaseMonomer.ts b/packages/ketcher-core/src/domain/entities/BaseMonomer.ts
index 6b9f4ede91..1c686bee69 100644
--- a/packages/ketcher-core/src/domain/entities/BaseMonomer.ts
+++ b/packages/ketcher-core/src/domain/entities/BaseMonomer.ts
@@ -13,6 +13,7 @@ import assert from 'assert';
 import {
   IKetAttachmentPoint,
   IKetAttachmentPointType,
+  KetMonomerClass,
 } from 'application/formatters/types/ket';
 import { RnaSubChain } from 'domain/entities/monomer-chains/RnaSubChain';
 import { ChemSubChain } from 'domain/entities/monomer-chains/ChemSubChain';
@@ -329,6 +330,10 @@ export abstract class BaseMonomer extends DrawingEntity {
     return this.attachmentPointsToBonds[attachmentPointName] !== undefined;
   }
 
+  public get isPhosphate() {
+    return this.monomerItem?.props?.MonomerClass === KetMonomerClass.Phosphate;
+  }
+
   public get usedAttachmentPointsNamesList() {
     const list: AttachmentPointName[] = [];