From 5475ef2db3d85a66379e3e69e82a897896b66881 Mon Sep 17 00:00:00 2001
From: David Saz <david.saz.g@gmail.com>
Date: Tue, 5 May 2026 00:24:03 +0200
Subject: [PATCH] Feat/add ide opened file to chat context (#1106)

* feat(chat): add active editor file context and related functionality

* feat(chat): improve active editor file context handling and update translations

* feat(i18n): standardize quotation marks in file attachment messages

* update Korean translation for image removal action in file attachment

* feat(chat): refine active editor file handling and optimize broadcast logic

* fix(chat): stabilize VS Code editor context chips

---------

Signed-off-by: David Saz <david.saz.g@gmail.com>
Co-authored-by: Bohdan Triapitsyn <artmore@protonmail.com>
---
 packages/ui/src/components/chat/ChatInput.tsx | 172 +++++++--------
 .../ui/src/components/chat/FileAttachment.tsx | 199 ++++++++++++++++--
 packages/ui/src/lib/i18n/messages/en.ts       |   3 +
 packages/ui/src/lib/i18n/messages/es.ts       |   3 +
 packages/ui/src/lib/i18n/messages/ko.ts       |   3 +
 packages/ui/src/lib/i18n/messages/pt-BR.ts    |   3 +
 packages/ui/src/lib/i18n/messages/uk.ts       |   3 +
 packages/ui/src/lib/i18n/messages/zh-CN.ts    |   3 +
 packages/ui/src/stores/types/sessionTypes.ts  |   4 +-
 packages/ui/src/sync/input-store.ts           | 113 ++++++++++
 packages/vscode/src/ChatViewProvider.ts       | 111 ++++++++++
 packages/vscode/webview/main.tsx              |   8 +
 12 files changed, 528 insertions(+), 97 deletions(-)

diff --git a/packages/ui/src/components/chat/ChatInput.tsx b/packages/ui/src/components/chat/ChatInput.tsx
index da009be6..54a2f420 100644
--- a/packages/ui/src/components/chat/ChatInput.tsx
+++ b/packages/ui/src/components/chat/ChatInput.tsx
@@ -29,7 +29,7 @@ import { useUserMessageHistory } from '@/sync/sync-context';
 import { useInlineCommentDraftStore, type InlineCommentDraft } from '@/stores/useInlineCommentDraftStore';
 import { appendInlineComments } from '@/lib/messages/inlineComments';
 import { renderMagicPrompt } from '@/lib/magicPrompts';
-import { AttachedFilesList } from './FileAttachment';
+import { AttachedFilesList, AttachedVSCodeFileChips, ActiveEditorFileSuggestion } from './FileAttachment';
 import { QueuedMessageChips } from './QueuedMessageChips';
 import { FileMentionAutocomplete, type FileMentionHandle } from './FileMentionAutocomplete';
 import { CommandAutocomplete, type CommandAutocompleteHandle, type CommandInfo } from './CommandAutocomplete';
@@ -3677,95 +3677,101 @@ const ChatInputComponent: React.FC<ChatInputProps> = ({ onOpenSettings, scrollTo
                                 : undefined}
                         />
                     )}
-                    <div className={cn("relative overflow-hidden", isDesktopExpanded && 'flex flex-1 min-h-0 flex-col')}>
-                        {highlightedComposerContent && (
-                            <div
-                                aria-hidden
+                    <div className={cn("overflow-hidden", isDesktopExpanded && 'flex flex-1 min-h-0 flex-col')}>
+                        <div className="flex items-center gap-1 px-3 pt-1 flex-wrap relative z-10">
+                            <AttachedVSCodeFileChips />
+                            <ActiveEditorFileSuggestion />
+                        </div>
+                        <div className={cn("relative overflow-hidden", isDesktopExpanded && 'flex flex-1 min-h-0 flex-col')}>
+                            {highlightedComposerContent && (
+                                <div
+                                    aria-hidden
+                                    className={cn(
+                                        'pointer-events-none absolute inset-0 z-0 whitespace-pre-wrap break-words px-3 rounded-b-none',
+                                        isDesktopExpanded
+                                            ? 'h-full min-h-0 py-4'
+                                            : isMobile
+                                                ? 'py-2.5'
+                                                : 'pt-4 pb-2',
+                                        inputMode === 'shell' ? 'font-mono' : 'typography-markdown md:typography-ui-label',
+                                    )}
+                                    ref={composerHighlightRef}
+                                >
+                                    {highlightedComposerContent.map((part, index) => (
+                                        <span
+                                            key={`${index}-${part.text.length}`}
+                                            className={
+                                                part.mentionKind === 'file'
+                                                    ? 'text-[var(--status-info)]'
+                                                    : part.mentionKind === 'agent'
+                                                        ? 'text-[var(--status-success)]'
+                                                        : 'text-foreground'
+                                            }
+                                        >
+                                            {part.text}
+                                        </span>
+                                    ))}
+                                </div>
+                            )}
+                            <Textarea
+                                simple
+                                ref={textareaRef}
+                                data-chat-input="true"
+                                value={message}
+                                onChange={handleTextChange}
+                                onBeforeInput={handleBeforeInput}
+                                onKeyDown={handleKeyDown}
+                                onPaste={handlePaste}
+                                onDragEnter={handleDragEnter}
+                                onDragOver={handleDragOver}
+                                onDropCapture={handleDropCapture}
+                                onDrop={handleDrop}
+                                onDragEnd={handleDragEnd}
+                                onKeyUp={updateAutocompleteOverlayPosition}
+                                onClick={updateAutocompleteOverlayPosition}
+                                onScroll={(event) => {
+                                    updateAutocompleteOverlayPosition();
+                                    const scrollTop = event.currentTarget.scrollTop;
+                                    if (composerHighlightRef.current) {
+                                        composerHighlightRef.current.style.transform = `translateY(-${scrollTop}px)`;
+                                    }
+                                }}
+                                onSelect={(e) => {
+                                    const ta = e.currentTarget;
+                                    cursorPosRef.current = ta.selectionStart ?? 0;
+                                    updateAutocompleteOverlayPosition();
+                                }}
+                                placeholder={currentSessionId || newSessionDraftOpen
+                                    ? inputMode === 'shell'
+                                        ? t('chat.chatInput.placeholder.shell')
+                                        : t('chat.chatInput.placeholder.chat')
+                                    : t('chat.chatInput.placeholder.selectSession')}
+                                disabled={!currentSessionId && !newSessionDraftOpen}
+                                autoCorrect={isMobile ? "on" : "off"}
+                                autoCapitalize={isMobile ? "sentences" : "off"}
+                                spellCheck={isMobile || inputSpellcheckEnabled}
+                                fillContainer={isDesktopExpanded}
+                                outerClassName={cn('ring-0 bg-transparent shadow-none hover:bg-transparent focus-within:ring-0', isDesktopExpanded && 'flex-1 min-h-0')}
                                 className={cn(
-                                    'pointer-events-none absolute inset-0 z-0 whitespace-pre-wrap break-words px-3 rounded-b-none',
+                                    'min-h-[52px] resize-none border-0 px-3 rounded-b-none appearance-none hover:border-transparent bg-transparent relative z-10',
                                     isDesktopExpanded
                                         ? 'h-full min-h-0 py-4'
                                         : isMobile
                                             ? 'py-2.5'
                                             : 'pt-4 pb-2',
-                                    inputMode === 'shell' ? 'font-mono' : 'typography-markdown md:typography-ui-label',
+                                    inputMode === 'shell' && 'font-mono',
+                                    highlightedComposerContent && 'text-transparent caret-[var(--surface-foreground)]',
                                 )}
-                                ref={composerHighlightRef}
-                            >
-                                {highlightedComposerContent.map((part, index) => (
-                                    <span
-                                        key={`${index}-${part.text.length}`}
-                                        className={
-                                            part.mentionKind === 'file'
-                                                ? 'text-[var(--status-info)]'
-                                                : part.mentionKind === 'agent'
-                                                    ? 'text-[var(--status-success)]'
-                                                    : 'text-foreground'
-                                        }
-                                    >
-                                        {part.text}
-                                    </span>
-                                ))}
-                            </div>
-                        )}
-                        <Textarea
-                            simple
-                            ref={textareaRef}
-                            data-chat-input="true"
-                            value={message}
-                            onChange={handleTextChange}
-                            onBeforeInput={handleBeforeInput}
-                            onKeyDown={handleKeyDown}
-                            onPaste={handlePaste}
-                            onDragEnter={handleDragEnter}
-                            onDragOver={handleDragOver}
-                            onDropCapture={handleDropCapture}
-                            onDrop={handleDrop}
-                            onDragEnd={handleDragEnd}
-                            onKeyUp={updateAutocompleteOverlayPosition}
-                            onClick={updateAutocompleteOverlayPosition}
-                            onScroll={(event) => {
-                                updateAutocompleteOverlayPosition();
-                                const scrollTop = event.currentTarget.scrollTop;
-                                if (composerHighlightRef.current) {
-                                    composerHighlightRef.current.style.transform = `translateY(-${scrollTop}px)`;
-                                }
-                            }}
-                            onSelect={(e) => {
-                                const ta = e.currentTarget;
-                                cursorPosRef.current = ta.selectionStart ?? 0;
-                                updateAutocompleteOverlayPosition();
-                            }}
-                            placeholder={currentSessionId || newSessionDraftOpen
-                                ? inputMode === 'shell'
-                                    ? t('chat.chatInput.placeholder.shell')
-                                    : t('chat.chatInput.placeholder.chat')
-                                : t('chat.chatInput.placeholder.selectSession')}
-                            disabled={!currentSessionId && !newSessionDraftOpen}
-                            autoCorrect={isMobile ? "on" : "off"}
-                            autoCapitalize={isMobile ? "sentences" : "off"}
-                            spellCheck={isMobile || inputSpellcheckEnabled}
-                            fillContainer={isDesktopExpanded}
-                            outerClassName={cn('ring-0 bg-transparent shadow-none hover:bg-transparent focus-within:ring-0', isDesktopExpanded && 'flex-1 min-h-0')}
-                            className={cn(
-                                'min-h-[52px] resize-none border-0 px-3 rounded-b-none appearance-none hover:border-transparent bg-transparent relative z-10',
-                                isDesktopExpanded
-                                    ? 'h-full min-h-0 py-4'
-                                    : isMobile
-                                        ? 'py-2.5'
-                                        : 'pt-4 pb-2',
-                                inputMode === 'shell' && 'font-mono',
-                                highlightedComposerContent && 'text-transparent caret-[var(--surface-foreground)]',
-                            )}
-                            style={{
-                                flex: isDesktopExpanded ? '1 1 auto' : 'none',
-                                height: !isDesktopExpanded && textareaSize ? `${textareaSize.height}px` : undefined,
-                                maxHeight: !isDesktopExpanded && textareaSize ? `${textareaSize.maxHeight}px` : undefined,
-                                borderTopLeftRadius: chatInputRadius,
-                                borderTopRightRadius: chatInputRadius,
-                            }}
-                            rows={1}
-                        />
+                                style={{
+                                    flex: isDesktopExpanded ? '1 1 auto' : 'none',
+                                    height: !isDesktopExpanded && textareaSize ? `${textareaSize.height}px` : undefined,
+                                    maxHeight: !isDesktopExpanded && textareaSize ? `${textareaSize.maxHeight}px` : undefined,
+                                    borderTopLeftRadius: chatInputRadius,
+                                    borderTopRightRadius: chatInputRadius,
+                                }}
+                                rows={1}
+                            />
+                        </div>
                     </div>
                     <div
                         className={cn(
diff --git a/packages/ui/src/components/chat/FileAttachment.tsx b/packages/ui/src/components/chat/FileAttachment.tsx
index 9d7f38c9..1caecbb0 100644
--- a/packages/ui/src/components/chat/FileAttachment.tsx
+++ b/packages/ui/src/components/chat/FileAttachment.tsx
@@ -1,5 +1,5 @@
 import React, { useRef, memo } from 'react';
-import { RiAttachment2, RiCloseLine, RiFileImageLine, RiFileLine, RiFilePdfLine, RiGithubLine, RiGitPullRequestLine } from '@remixicon/react';
+import { RiAttachment2, RiCloseLine, RiFileImageLine, RiFileLine, RiFilePdfLine, RiGithubLine, RiGitPullRequestLine, RiAddLine, RiPushpin2Line } from '@remixicon/react';
 import { useInputStore } from '@/sync/input-store';
 import type { AttachedFile } from '@/sync/session-ui-store';
 import { useUIStore } from '@/stores/useUIStore';
@@ -202,13 +202,7 @@ const ImagePreview = memo(({ file, onRemove }: ImagePreviewProps) => {
 
 ImagePreview.displayName = 'ImagePreview';
 
-interface FileChipProps {
-  file: AttachedFile;
-  onRemove: () => void;
-}
-
-const FileChip = memo(({ file, onRemove }: FileChipProps) => {
-  const { t } = useI18n();
+const useFileDetails = (file: AttachedFile) => {
   const getFileExtension = (filename: string): string => {
     const parts = filename.split('.');
     return parts.length > 1 ? parts[parts.length - 1].toLowerCase() : '';
@@ -228,9 +222,21 @@ const FileChip = memo(({ file, onRemove }: FileChipProps) => {
     return filename || path;
   };
 
-  const displayName = extractFilename(file.filename);
-  const fileSize = formatFileSize(file.size);
-  const extension = getFileExtension(file.filename);
+  return {
+    displayName: extractFilename(file.filename),
+    fileSize: formatFileSize(file.size),
+    extension: getFileExtension(file.filename),
+  };
+};
+
+interface FileChipProps {
+  file: AttachedFile;
+  onRemove: () => void;
+}
+
+const FileChip = memo(({ file, onRemove }: FileChipProps) => {
+  const { t } = useI18n();
+  const { displayName, fileSize, extension } = useFileDetails(file);
 
   return (
     <button
@@ -265,11 +271,78 @@ const FileChip = memo(({ file, onRemove }: FileChipProps) => {
 
 FileChip.displayName = 'FileChip';
 
+const VSCodeFileChip = memo(({ file, onRemove }: FileChipProps) => {
+  const { t } = useI18n();
+  const { displayName, extension } = useFileDetails(file);
+  
+  // Detect selection-style attachments: ends with ":N" or ":N-M"
+  const isSelectionAttachment = /:\d+(?:-\d+)?$/.test(displayName);
+
+  return (
+    <button
+      type="button"
+      onClick={(e) => {
+        // Prevent click from bubbling if clicking the remove button
+        if ((e.target as HTMLElement).closest('[data-remove-button]')) {
+          return;
+        }
+      }}
+      className="inline-flex items-center gap-1 text-xs pr-1 rounded-sm border border-solid bg-transparent text-foreground not-italic hover:opacity-90 transition-colors text-left"
+      style={{ borderColor: 'var(--syntax-punctuation)' }}
+      title={file.vscodePath}
+    >
+      <span
+        data-remove-button
+        onClick={(e) => {
+          e.stopPropagation();
+          onRemove();
+        }}
+        className="flex items-center justify-center h-5 w-5 flex-shrink-0 hover:bg-[var(--interactive-hover)] rounded-full transition-colors cursor-pointer"
+        aria-label={t('chat.fileAttachment.activeEditor.remove')}
+        title={t('chat.fileAttachment.activeEditor.remove')}
+      >
+        <RiCloseLine className="h-4 w-4 text-muted-foreground" />
+      </span>
+        <FileTypeIcon filePath={file.filename} extension={extension} className="h-4 w-4" />
+        <span className={cn('text-foreground', isSelectionAttachment ? 'whitespace-nowrap' : 'truncate max-w-[200px]')}>
+          {displayName}
+        </span>
+    </button>
+  );
+});
+
+VSCodeFileChip.displayName = 'VSCodeFileChip';
+
+export const AttachedVSCodeFileChips = memo(() => {  
+  const attachedFiles = useInputStore((state) => state.attachedFiles);
+  const removeAttachedFile = useInputStore((state) => state.removeAttachedFile);
+
+  const vscodeFiles = attachedFiles.filter((file) => file.source === 'vscode');
+
+  if (vscodeFiles.length === 0) return null;
+
+  const images = vscodeFiles.filter((f) => f.mimeType.startsWith('image/'));
+  const otherFiles = vscodeFiles.filter((f) => !f.mimeType.startsWith('image/'));
+
+  return (
+    <div className="flex items-center gap-2 flex-wrap">
+      {images.map((file) => (
+        <ImagePreview key={file.id} file={file} onRemove={() => removeAttachedFile(file.id)} />
+      ))}
+      {otherFiles.map((file) => (
+        <VSCodeFileChip key={file.id} file={file} onRemove={() => removeAttachedFile(file.id)} />
+      ))}
+    </div>
+  );
+});
+
+AttachedVSCodeFileChips.displayName = 'AttachedVSCodeFileChips';
+
 export const AttachedFilesList = memo(() => {
   const attachedFiles = useInputStore((state) => state.attachedFiles);
   const removeAttachedFile = useInputStore((state) => state.removeAttachedFile);
 
-  const localFiles = attachedFiles.filter((file) => file.source !== 'server');
+  const localFiles = attachedFiles.filter((file) => file.source !== 'server' && file.source !== 'vscode');
 
   if (localFiles.length === 0) return null;
 
@@ -309,6 +382,105 @@ export const AttachedFilesList = memo(() => {
 
 AttachedFilesList.displayName = 'AttachedFilesList';
 
+export const ActiveEditorFileSuggestion = memo(() => {
+  const { t } = useI18n();
+  const activeEditorFile = useInputStore((s) => s.activeEditorFile);
+  const attachedFiles = useInputStore((s) => s.attachedFiles)
+  const addVSCodeFileAttachment = useInputStore((s) => s.addVSCodeFileAttachment)
+  const addVSCodeSelectionAttachment = useInputStore((s) => s.addVSCodeSelectionAttachment)
+  const isVSCodeRuntime = useIsVSCodeRuntime();
+
+  if (!isVSCodeRuntime || !activeEditorFile) return null;
+
+  const { filePath, fileName, relativePath, selection, fileSize } = activeEditorFile;
+
+  // Normalize to forward slashes for comparison
+  const isFileAttached = attachedFiles.some(
+    (f) => f.source === 'vscode' && f.vscodeSource === 'file' && (f.vscodePath || '') === filePath
+  )
+
+  // Compute selection label using a compact range (single line shown as "N" not "N-N")
+  let selectionRange = ''
+  if (selection) {
+    selectionRange = selection.startLine === selection.endLine
+      ? `${selection.startLine}`
+      : `${selection.startLine}-${selection.endLine}`
+  }
+  const selectionLabel = selection ? `${fileName}:${selectionRange}` : ''
+  const isSelectionAttached = !!selectionLabel && attachedFiles.some(
+    (f) => f.source === 'vscode' && f.vscodeSource === 'selection' && f.filename === selectionLabel && f.vscodePath === filePath
+  )
+
+  // Nothing to show — file is already attached and there's no (or already-attached) selection
+  if (isFileAttached && (!selection || isSelectionAttached)) return null;
+
+  const ext = fileName.split('.').pop() || '';
+  // Always show only the filename in the suggestion UI
+  const displayName = fileName;
+
+  const handleAddFile = () => {
+    addVSCodeFileAttachment(filePath, fileName, fileSize);
+  };
+
+  const handlePinSelection = async () => {
+    if (!selection) return;
+    const blob = new Blob([selection.text], { type: 'text/plain' });
+    const file = new File([blob], selectionLabel, { type: 'text/plain' });
+    await addVSCodeSelectionAttachment(filePath, file);
+  };
+
+  // If there is a selection, prefer showing the pin-selection UI only.
+  const showSelectionPin = !!selection && !isSelectionAttached;
+  const showFileAdd = !showSelectionPin && !isFileAttached;
+
+  if (!showSelectionPin && !showFileAdd) return null;
+
+  return (
+    <div className="inline-flex items-center">
+      {showSelectionPin && (
+        <div
+          className="inline-flex items-center gap-1 text-xs pr-1 rounded-sm italic text-muted-foreground border border-dashed bg-transparent"
+          style={{ borderColor: 'var(--syntax-punctuation)' }}
+          title={relativePath}
+        >
+          <button
+            type="button"
+            title={t('chat.fileAttachment.activeEditor.pinSelection')}
+            aria-label={t('chat.fileAttachment.activeEditor.pinSelection')}
+            onClick={() => { void handlePinSelection(); }}
+            className="flex items-center justify-center h-5 w-5 flex-shrink-0 hover:bg-[var(--interactive-hover)] rounded-full transition-colors cursor-pointer"
+          >
+            <RiPushpin2Line className="h-4 w-4" />
+          </button>
+          <FileTypeIcon filePath={fileName} extension={ext} className="h-4 w-4 flex-shrink-0" />
+          <span className="text-xs whitespace-nowrap">{`${displayName}:${selectionRange}`}</span>
+        </div>
+      )}
+      {showFileAdd && (
+        <div
+          className="inline-flex items-center gap-1 text-xs pr-1 rounded-sm italic text-muted-foreground border border-dashed bg-transparent"
+          style={{ borderColor: 'var(--syntax-punctuation)' }}
+          title={relativePath}
+        >
+          <button
+            type="button"
+            title={t('chat.fileAttachment.activeEditor.addFile', { name: displayName })}
+            aria-label={t('chat.fileAttachment.activeEditor.addFile', { name: displayName })}
+            onClick={handleAddFile}
+            className="flex items-center justify-center h-5 w-5 flex-shrink-0 hover:bg-[var(--interactive-hover)] rounded-full transition-colors cursor-pointer"
+          >
+            <RiAddLine className="h-4 w-4" />
+          </button>
+          <FileTypeIcon filePath={fileName} extension={ext} className="h-4 w-4 flex-shrink-0" />
+          <span className="text-xs truncate max-w-[220px]">{displayName}</span>
+        </div>
+      )}
+    </div>
+  );
+});
+
+ActiveEditorFileSuggestion.displayName = 'ActiveEditorFileSuggestion';
+
 interface FilePart {
   type: string;
   mime?: string;
@@ -423,6 +595,7 @@ export const MessageFilesDisplay = memo(({ files, onShowPopup, compact = false }
           <div className="flex flex-wrap gap-1.5">
             {otherFiles.map((file, index) => {
               const fileName = resolveDisplayName(file);
+              const ext = fileName.split('.').pop() || '';
               const sizeText = formatFileSize(file.size);
               const githubLinkKind = getGitHubLinkKind(file);
               return (
@@ -450,7 +623,7 @@ export const MessageFilesDisplay = memo(({ files, onShowPopup, compact = false }
                         {file.mime?.includes('pdf') ? (
                           <RiFilePdfLine className="text-muted-foreground h-3.5 w-3.5" />
                         ) : (
-                          <RiFileLine className="text-muted-foreground h-3.5 w-3.5" />
+                          <FileTypeIcon filePath={fileName} extension={ext} className="text-muted-foreground h-3.5 w-3.5" />
                         )}
                         <div className="overflow-hidden max-w-[140px]">
                           <span className="truncate block" title={fileName}>{fileName}</span>
diff --git a/packages/ui/src/lib/i18n/messages/en.ts b/packages/ui/src/lib/i18n/messages/en.ts
index 779662aa..f61b0e0f 100644
--- a/packages/ui/src/lib/i18n/messages/en.ts
+++ b/packages/ui/src/lib/i18n/messages/en.ts
@@ -1278,6 +1278,9 @@ export const dict = {
   'chat.fileAttachment.actions.attach': 'Attach files',
   'chat.fileAttachment.actions.removeNamed': 'Remove {name}',
   'chat.fileAttachment.actions.removeImage': 'Remove image',
+  'chat.fileAttachment.activeEditor.addFile': 'Add file:{name} to context',
+  'chat.fileAttachment.activeEditor.pinSelection': 'Pin selection to context',
+  'chat.fileAttachment.activeEditor.remove': 'Remove from context',
   'chat.pendingChanges.fileCountSingle': '{count} file',
   'chat.pendingChanges.fileCountPlural': '{count} files',
   'chat.pendingChanges.changedInWorkspace': 'changed in workspace',
diff --git a/packages/ui/src/lib/i18n/messages/es.ts b/packages/ui/src/lib/i18n/messages/es.ts
index 4931df1e..d8f35860 100644
--- a/packages/ui/src/lib/i18n/messages/es.ts
+++ b/packages/ui/src/lib/i18n/messages/es.ts
@@ -1244,6 +1244,9 @@ export const dict: Record<I18nKey, string> = {
   "chat.fileAttachment.actions.attach": "Adjuntar archivos",
   "chat.fileAttachment.actions.removeNamed": "Eliminar {name}",
   "chat.fileAttachment.actions.removeImage": "Eliminar imagen",
+  "chat.fileAttachment.activeEditor.addFile": "Agregar archivo:{name} al contexto",
+  "chat.fileAttachment.activeEditor.pinSelection": "Anclar selección al contexto",
+  "chat.fileAttachment.activeEditor.remove": "Quitar del contexto",
   "chat.pendingChanges.fileCountSingle": "{count} archivo",
   "chat.pendingChanges.fileCountPlural": "{count} archivos",
   "chat.pendingChanges.changedInWorkspace": "modificado en el espacio de trabajo",
diff --git a/packages/ui/src/lib/i18n/messages/ko.ts b/packages/ui/src/lib/i18n/messages/ko.ts
index 66c15393..8fa81700 100644
--- a/packages/ui/src/lib/i18n/messages/ko.ts
+++ b/packages/ui/src/lib/i18n/messages/ko.ts
@@ -1280,6 +1280,9 @@ export const dict: Record<I18nKey, string> = {
   'chat.fileAttachment.actions.attach': '파일 첨부',
   'chat.fileAttachment.actions.removeNamed': '{name} 제거',
   'chat.fileAttachment.actions.removeImage': '이미지 제거',
+  'chat.fileAttachment.activeEditor.addFile': '컨텍스트에 파일 추가:{name}',
+  'chat.fileAttachment.activeEditor.pinSelection': '컨텍스트에 선택 고정',
+  'chat.fileAttachment.activeEditor.remove': '컨텍스트에서 제거',
   'chat.pendingChanges.fileCountSingle': '{count} 파일',
   'chat.pendingChanges.fileCountPlural': '{count} 파일',
   'chat.pendingChanges.changedInWorkspace': '워크스페이스에서 변경됨',
diff --git a/packages/ui/src/lib/i18n/messages/pt-BR.ts b/packages/ui/src/lib/i18n/messages/pt-BR.ts
index b0faf229..3e400d79 100644
--- a/packages/ui/src/lib/i18n/messages/pt-BR.ts
+++ b/packages/ui/src/lib/i18n/messages/pt-BR.ts
@@ -1244,6 +1244,9 @@ export const dict: Record<I18nKey, string> = {
   "chat.fileAttachment.actions.attach": "Anexar arquivos",
   "chat.fileAttachment.actions.removeNamed": "Excluir {name}",
   "chat.fileAttachment.actions.removeImage": "Excluir imagem",
+  "chat.fileAttachment.activeEditor.addFile": "Adicionar arquivo:{name} ao contexto",
+  "chat.fileAttachment.activeEditor.pinSelection": "Fixar seleção no contexto",
+  "chat.fileAttachment.activeEditor.remove": "Remover do contexto",
   "chat.pendingChanges.fileCountSingle": "{count} arquivo",
   "chat.pendingChanges.fileCountPlural": "{count} arquivos",
   "chat.pendingChanges.changedInWorkspace": "modificado no workspace",
diff --git a/packages/ui/src/lib/i18n/messages/uk.ts b/packages/ui/src/lib/i18n/messages/uk.ts
index d9f144e4..f5a32f2f 100644
--- a/packages/ui/src/lib/i18n/messages/uk.ts
+++ b/packages/ui/src/lib/i18n/messages/uk.ts
@@ -1244,6 +1244,9 @@ export const dict: Record<I18nKey, string> = {
   "chat.fileAttachment.actions.attach": "Прикріпити файли",
   "chat.fileAttachment.actions.removeNamed": "Видалити {name}",
   "chat.fileAttachment.actions.removeImage": "Видалити зображення",
+  "chat.fileAttachment.activeEditor.addFile": "Додати файл:{name} до контексту",
+  "chat.fileAttachment.activeEditor.pinSelection": "Закріпити вибір у контексті",
+  "chat.fileAttachment.activeEditor.remove": "Видалити з контексту",
   "chat.pendingChanges.fileCountSingle": "Файл: {count}",
   "chat.pendingChanges.fileCountPlural": "Файлів: {count}",
   "chat.pendingChanges.changedInWorkspace": "змінено в гілці",
diff --git a/packages/ui/src/lib/i18n/messages/zh-CN.ts b/packages/ui/src/lib/i18n/messages/zh-CN.ts
index a154c846..5183712a 100644
--- a/packages/ui/src/lib/i18n/messages/zh-CN.ts
+++ b/packages/ui/src/lib/i18n/messages/zh-CN.ts
@@ -1244,6 +1244,9 @@ export const dict: Record<I18nKey, string> = {
   'chat.fileAttachment.actions.attach': '附加文件',
   'chat.fileAttachment.actions.removeNamed': '移除 {name}',
   'chat.fileAttachment.actions.removeImage': '移除图片',
+  'chat.fileAttachment.activeEditor.addFile': '将文件添加到上下文:{name}',
+  'chat.fileAttachment.activeEditor.pinSelection': '将选择固定到上下文',
+  'chat.fileAttachment.activeEditor.remove': '从上下文中移除',
   'chat.pendingChanges.fileCountSingle': '{count} 个文件',
   'chat.pendingChanges.fileCountPlural': '{count} 个文件',
   'chat.pendingChanges.changedInWorkspace': '工作区中有变更',
diff --git a/packages/ui/src/stores/types/sessionTypes.ts b/packages/ui/src/stores/types/sessionTypes.ts
index ba1b938f..d2827ff4 100644
--- a/packages/ui/src/stores/types/sessionTypes.ts
+++ b/packages/ui/src/stores/types/sessionTypes.ts
@@ -21,8 +21,10 @@ export interface AttachedFile {
     mimeType: string;
     filename: string;
     size: number;
-    source: "local" | "server";
+    source: "local" | "server" | "vscode";
     serverPath?: string;
+    vscodePath?: string;
+    vscodeSource?: 'file' | 'selection';
 }
 
 export type EditPermissionMode = 'allow' | 'ask' | 'deny' | 'full';
diff --git a/packages/ui/src/sync/input-store.ts b/packages/ui/src/sync/input-store.ts
index cc61897e..284d43b7 100644
--- a/packages/ui/src/sync/input-store.ts
+++ b/packages/ui/src/sync/input-store.ts
@@ -6,17 +6,65 @@
 import { create } from "zustand"
 import type { AttachedFile } from "@/stores/types/sessionTypes"
 
+const FILE_URI_PREFIX = "file://"
+const pendingVSCodeSelectionKeys = new Set<string>()
+
+const encodeFilePath = (filepath: string): string => {
+  let normalized = filepath.replace(/\\/g, "/")
+  if (/^[A-Za-z]:/.test(normalized)) {
+    normalized = `/${normalized}`
+  }
+  return normalized
+    .split("/")
+    .map((segment, index) => {
+      if (index === 1 && /^[A-Za-z]:$/.test(segment)) return segment
+      return encodeURIComponent(segment)
+    })
+    .join("/")
+}
+
+const toFileUrl = (filepath: string): string => {
+  const normalized = filepath.replace(/\\/g, "/").trim()
+  if (normalized.toLowerCase().startsWith(FILE_URI_PREFIX)) {
+    return normalized
+  }
+  return `${FILE_URI_PREFIX}${encodeFilePath(normalized)}`
+}
+
+const getVSCodeSelectionKey = (path: string, filename: string): string => `${path}\u0000${filename}`
+
+const isSameVSCodeActiveEditorFile = (a: VSCodeActiveEditorFile | null, b: VSCodeActiveEditorFile | null): boolean => {
+  if (a === b) return true
+  if (!a || !b) return false
+  return a.filePath === b.filePath
+    && a.fileName === b.fileName
+    && a.relativePath === b.relativePath
+    && a.fileSize === b.fileSize
+    && a.selection?.startLine === b.selection?.startLine
+    && a.selection?.endLine === b.selection?.endLine
+    && a.selection?.text === b.selection?.text
+}
+
 export type SyntheticContextPart = {
   text: string
   attachments?: AttachedFile[]
   synthetic?: boolean
 }
 
+export type VSCodeActiveEditorFile = {
+  filePath: string
+  fileName: string
+  relativePath: string
+  fileSize: number | null
+  selection: { startLine: number; endLine: number; text: string } | null
+}
+
 export type InputState = {
   pendingInputText: string | null
   pendingInputMode: "replace" | "append" | "append-inline"
   pendingSyntheticParts: SyntheticContextPart[] | null
   attachedFiles: AttachedFile[]
+  activeEditorFile: VSCodeActiveEditorFile | null
 
   setPendingInputText: (text: string | null, mode?: "replace" | "append" | "append-inline") => void
   consumePendingInputText: () => { text: string; mode: "replace" | "append" | "append-inline" } | null
@@ -25,6 +73,9 @@ export type InputState = {
   addAttachedFile: (file: File) => Promise<void>
   removeAttachedFile: (id: string) => void
   clearAttachedFiles: () => void
+  addVSCodeFileAttachment: (path: string, name: string, fileSize: number | null) => void
+  addVSCodeSelectionAttachment: (path: string, file: File) => Promise<void>
+  setActiveEditorFile: (file: VSCodeActiveEditorFile | null) => void
 }
 
 export const useInputStore = create<InputState>()((set, get) => ({
@@ -32,6 +83,7 @@ export const useInputStore = create<InputState>()((set, get) => ({
   pendingInputMode: "replace",
   pendingSyntheticParts: null,
   attachedFiles: [],
+  activeEditorFile: null,
 
   setPendingInputText: (text, mode = "replace") =>
     set({ pendingInputText: text, pendingInputMode: mode }),
@@ -76,4 +128,65 @@ export const useInputStore = create<InputState>()((set, get) => ({
     set((s) => ({ attachedFiles: s.attachedFiles.filter((f) => f.id !== id) })),
 
   clearAttachedFiles: () => set({ attachedFiles: [] }),
+
+  addVSCodeFileAttachment: (path: string, name: string, fileSize: number | null) => {
+    const id = `${Date.now()}-${Math.random().toString(36).slice(2)}`
+    const isDuplicate = get().attachedFiles.some(
+      (f) => f.source === 'vscode' && f.vscodeSource === 'file' && (f.vscodePath || '') === path
+    )
+    if (isDuplicate) return
+    const dataUrl = toFileUrl(path)
+    // `file://` URLs are the same contract used by server-source attachments.
+    // The submission path passes `dataUrl` as `url` directly to the OpenCode
+    // server, which resolves `file://` paths natively. No base64 encoding needed.
+    const attached: AttachedFile = {
+      id,
+      file: new File([], name, { type: 'text/plain' }),
+      dataUrl,
+      mimeType: 'text/plain',
+      filename: name,
+      size: fileSize || 0,
+      source: 'vscode',
+      vscodePath: path,
+      vscodeSource: 'file',
+    }
+    set((s) => ({ attachedFiles: [...s.attachedFiles, attached] }))
+  },
+
+  addVSCodeSelectionAttachment: async (path: string, file: File) => {
+    const id = `${Date.now()}-${Math.random().toString(36).slice(2)}`
+    const selectionKey = getVSCodeSelectionKey(path, file.name)
+    const isDuplicate = get().attachedFiles.some(
+      (f) => f.source === 'vscode' && f.vscodeSource === 'selection' && f.filename === file.name && f.vscodePath === path
+    )
+    if (isDuplicate || pendingVSCodeSelectionKeys.has(selectionKey)) return
+    pendingVSCodeSelectionKeys.add(selectionKey)
+    let dataUrl: string
+    try {
+      dataUrl = await new Promise<string>((resolve) => {
+        const reader = new FileReader()
+        reader.onload = () => resolve(reader.result as string)
+        reader.readAsDataURL(file)
+      })
+    } finally {
+      pendingVSCodeSelectionKeys.delete(selectionKey)
+    }
+    const attached: AttachedFile = {
+      id,
+      file,
+      dataUrl,
+      mimeType: file.type,
+      filename: file.name,
+      size: file.size,
+      source: 'vscode',
+      vscodePath: path,
+      vscodeSource: 'selection',
+    }
+    set((s) => ({ attachedFiles: [...s.attachedFiles, attached] }))
+  },
+
+  setActiveEditorFile: (file) => {
+    if (isSameVSCodeActiveEditorFile(get().activeEditorFile, file)) return
+    set({ activeEditorFile: file })
+  },
 }))
diff --git a/packages/vscode/src/ChatViewProvider.ts b/packages/vscode/src/ChatViewProvider.ts
index 7f2963d4..e8b1b395 100644
--- a/packages/vscode/src/ChatViewProvider.ts
+++ b/packages/vscode/src/ChatViewProvider.ts
@@ -8,6 +8,26 @@ import { openSseProxy } from './sseProxy';
 import { resolveWebviewDevServerUrl } from './webviewDevServer';
 import { normalizeWindowsDriveLetter } from './pathUtils';
 
+type ActiveEditorFilePayload = {
+  filePath: string;
+  fileName: string;
+  relativePath: string;
+  fileSize: number | null;
+  selection: { startLine: number; endLine: number; text: string } | null;
+};
+
+const isSameActiveEditorFilePayload = (a: ActiveEditorFilePayload | null, b: ActiveEditorFilePayload | null): boolean => {
+  if (a === b) return true;
+  if (!a || !b) return false;
+  return a.filePath === b.filePath
+    && a.fileName === b.fileName
+    && a.relativePath === b.relativePath
+    && a.fileSize === b.fileSize
+    && a.selection?.startLine === b.selection?.startLine
+    && a.selection?.endLine === b.selection?.endLine
+    && a.selection?.text === b.selection?.text;
+};
+
 export class ChatViewProvider implements vscode.WebviewViewProvider {
   public static readonly viewType = 'openchamber.chatView';
 
@@ -23,6 +43,9 @@ export class ChatViewProvider implements vscode.WebviewViewProvider {
   private _sseCounter = 0;
   private _sseStreams = new Map<string, AbortController>();
   private readonly _webviewDevServerUrl: string | null;
+  private _broadcastSelectionDebounce: ReturnType<typeof setTimeout> | undefined;
+  private _clearActiveEditorFileTimer: ReturnType<typeof setTimeout> | undefined;
+  private _lastActiveEditorFilePayload: ActiveEditorFilePayload | null = null;
 
   // Message delivery confirmation and retry
   private readonly _pendingMessages = new Set<string>();
@@ -48,6 +71,11 @@ export class ChatViewProvider implements vscode.WebviewViewProvider {
     private readonly _openCodeManager?: OpenCodeManager
   ) {
     this._webviewDevServerUrl = resolveWebviewDevServerUrl(this._context);
+
+    this._context.subscriptions.push(
+      vscode.window.onDidChangeActiveTextEditor(() => void this._broadcastActiveEditorFile()),
+      vscode.window.onDidChangeTextEditorSelection(() => this._scheduleBroadcast()),
+    );
   }
 
   public resolveWebviewView(
@@ -70,6 +98,10 @@ export class ChatViewProvider implements vscode.WebviewViewProvider {
     // Send cached connection status and API URL (may have been set before webview was resolved)
     this._sendCachedState();
 
+    // Send current active editor file state to the new webview
+    this._lastActiveEditorFilePayload = null;
+    void this._broadcastActiveEditorFile();
+
     webviewView.onDidDispose(() => {
       this._clearPendingMessages();
     });
@@ -304,6 +336,85 @@ export class ChatViewProvider implements vscode.WebviewViewProvider {
     });
   }
 
+  private _scheduleBroadcast(): void {
+    if (this._broadcastSelectionDebounce !== undefined) {
+      clearTimeout(this._broadcastSelectionDebounce);
+    }
+    this._broadcastSelectionDebounce = setTimeout(() => {
+      this._broadcastSelectionDebounce = undefined;
+      void this._broadcastActiveEditorFile();
+    }, 150);
+  }
+
+  private _scheduleClearActiveEditorFile(): void {
+    if (this._clearActiveEditorFileTimer !== undefined) {
+      clearTimeout(this._clearActiveEditorFileTimer);
+    }
+    this._clearActiveEditorFileTimer = setTimeout(() => {
+      this._clearActiveEditorFileTimer = undefined;
+      if (!this._view || this._lastActiveEditorFilePayload === null) {
+        return;
+      }
+      this._lastActiveEditorFilePayload = null;
+      this._view.webview.postMessage({
+        type: 'command',
+        command: 'activeEditorFile',
+        payload: null,
+      });
+    }, 200);
+  }
+
+  private async _broadcastActiveEditorFile() {
+    if (!this._view) {
+      return;
+    }
+
+    const editor = vscode.window.activeTextEditor;
+    if (!editor || editor.document.uri.scheme !== 'file') {
+      this._scheduleClearActiveEditorFile();
+      return;
+    }
+
+    if (this._clearActiveEditorFileTimer !== undefined) {
+      clearTimeout(this._clearActiveEditorFileTimer);
+      this._clearActiveEditorFileTimer = undefined;
+    }
+
+    const filePath = normalizeWindowsDriveLetter(editor.document.uri.fsPath);
+    const rawFileName = editor.document.uri.fsPath;
+    const fileName = rawFileName.replace(/\\/g, '/').split('/').pop() || '';
+    const relativePath = vscode.workspace.asRelativePath(editor.document.uri, false);
+
+    let fileSize: number | null = null;
+    try {
+      const stat = await vscode.workspace.fs.stat(editor.document.uri);
+      fileSize = stat.size;
+    } catch {
+      // File may not be saved yet or inaccessible
+    }
+
+    let selection: { startLine: number; endLine: number; text: string } | null = null;
+    if (!editor.selection.isEmpty) {
+      selection = {
+        startLine: editor.selection.start.line + 1,
+        endLine: editor.selection.end.line + 1,
+        text: editor.document.getText(editor.selection),
+      };
+    }
+
+    const payload: ActiveEditorFilePayload = { filePath, fileName, relativePath, fileSize, selection };
+    if (isSameActiveEditorFilePayload(this._lastActiveEditorFilePayload, payload)) {
+      return;
+    }
+    this._lastActiveEditorFilePayload = payload;
+
+    this._view.webview.postMessage({
+      type: 'command',
+      command: 'activeEditorFile',
+      payload,
+    });
+  }
+
   private _buildSseHeaders(extra?: Record<string, string>): Record<string, string> {
     return {
       Accept: 'text/event-stream',
diff --git a/packages/vscode/webview/main.tsx b/packages/vscode/webview/main.tsx
index 1ab4cbd4..8a121bb1 100644
--- a/packages/vscode/webview/main.tsx
+++ b/packages/vscode/webview/main.tsx
@@ -8,6 +8,7 @@ import {
   type VSCodeThemeKind,
   type VSCodeThemePayload,
 } from '@openchamber/ui/lib/theme/vscode/adapter';
+import type { VSCodeActiveEditorFile } from '@/sync/input-store';
 
 type ConnectionStatus = 'connecting' | 'connected' | 'error' | 'disconnected';
 type PanelType = 'chat' | 'agentManager';
@@ -1234,6 +1235,13 @@ onCommand('settingsSynced', () => {
   });
 });
 
+// Listen for active editor file changes from the extension
+onCommand('activeEditorFile', (payload) => {
+  import('@/sync/input-store').then(({ useInputStore }) => {
+    useInputStore.getState().setActiveEditorFile((payload as VSCodeActiveEditorFile | null) ?? null);
+  });
+});
+
 import('@/main')
   .then(async () => {
     await waitForUiMount();