diff --git a/backend/export.py b/backend/export.py
new file mode 100644
index 0000000..c6219b4
--- /dev/null
+++ b/backend/export.py
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+"""
+HTML Export Module for NoteDiscovery
+Generates standalone HTML files for notes with embedded images and styling.
+Used by both /api/export (download) and /public (sharing) endpoints.
+"""
+
+import base64
+import re
+from pathlib import Path
+from typing import Optional
+import mimetypes
+
+
+def get_image_as_base64(image_path: Path) -> Optional[str]:
+ """Read an image file and return it as a base64 data URL."""
+ if not image_path.exists() or not image_path.is_file():
+ return None
+
+ # Get MIME type
+ mime_type, _ = mimetypes.guess_type(str(image_path))
+ if not mime_type or not mime_type.startswith('image/'):
+ return None
+
+ try:
+ with open(image_path, 'rb') as f:
+ image_data = f.read()
+ base64_data = base64.b64encode(image_data).decode('utf-8')
+ return f"data:{mime_type};base64,{base64_data}"
+ except Exception as e:
+ print(f"Failed to read image {image_path}: {e}")
+ return None
+
+
+def strip_frontmatter(content: str) -> str:
+ """
+ Remove YAML frontmatter from markdown content.
+ Frontmatter is delimited by --- at the start and end.
+ """
+ if not content.strip().startswith('---'):
+ return content
+
+ lines = content.split('\n')
+ if lines[0].strip() != '---':
+ return content
+
+ # Find closing ---
+ end_idx = -1
+ for i in range(1, len(lines)):
+ if lines[i].strip() == '---':
+ end_idx = i
+ break
+
+ if end_idx == -1:
+ return content
+
+ # Remove frontmatter and return the rest
+ return '\n'.join(lines[end_idx + 1:]).strip()
+
+
+def find_image_in_attachments(image_name: str, note_folder: Path, notes_dir: Path) -> Optional[Path]:
+ """
+ Search for an image file in common attachment locations.
+ Returns the resolved path if found, None otherwise.
+ """
+ # Common locations to search for images (fast path)
+ search_paths = [
+ note_folder / image_name, # Same folder as note
+ note_folder / '_attachments' / image_name, # Note's _attachments folder
+ notes_dir / '_attachments' / image_name, # Root _attachments folder
+ ]
+
+ # Also search in parent folders' _attachments (for nested notes)
+ current = note_folder
+ while current != notes_dir and current.parent != current:
+ search_paths.append(current / '_attachments' / image_name)
+ current = current.parent
+
+ for path in search_paths:
+ resolved = path.resolve()
+ if resolved.exists() and resolved.is_file():
+ # Security: ensure path is within notes_dir
+ try:
+ resolved.relative_to(notes_dir.resolve())
+ return resolved
+ except ValueError:
+ continue
+
+ # Fallback: search all _attachments folders recursively (slower but thorough)
+ # This handles cross-folder image references like in Obsidian
+ try:
+ for attachment_folder in notes_dir.rglob('_attachments'):
+ if attachment_folder.is_dir():
+ candidate = attachment_folder / image_name
+ if candidate.exists() and candidate.is_file():
+ try:
+ candidate.resolve().relative_to(notes_dir.resolve())
+ return candidate.resolve()
+ except ValueError:
+ continue
+ except Exception:
+ pass # Ignore errors in recursive search
+
+ return None
+
+
+def embed_images_as_base64(markdown_content: str, note_folder: Path, notes_dir: Path) -> str:
+ """
+ Find all image references in markdown and embed them as base64.
+ Handles:
+ - Standard markdown images: 
+ - Wikilink images: ![[image.png]] or ![[image.png|alt text]]
+ """
+
+ # First, handle wikilink images: ![[image.png]] or ![[image.png|alt text]]
+ wikilink_img_pattern = r'!\[\[([^\]|]+)(?:\|([^\]]+))?\]\]'
+
+ def replace_wikilink_image(match):
+ image_name = match.group(1).strip()
+ alt_text = match.group(2).strip() if match.group(2) else image_name.split('/')[-1].rsplit('.', 1)[0]
+
+ # Find the image
+ resolved_path = find_image_in_attachments(image_name, note_folder, notes_dir)
+
+ if resolved_path:
+ base64_url = get_image_as_base64(resolved_path)
+ if base64_url:
+ return f''
+
+ # Image not found, convert to placeholder
+ return f'![{alt_text}]()'
+
+ markdown_content = re.sub(wikilink_img_pattern, replace_wikilink_image, markdown_content)
+
+ # Then, handle standard markdown images: 
+ img_pattern = r'!\[([^\]]*)\]\(([^)]+)\)'
+
+ def replace_image(match):
+ alt_text = match.group(1)
+ img_path = match.group(2)
+
+ # Skip external URLs and already-embedded base64
+ if img_path.startswith(('http://', 'https://', 'data:')):
+ return match.group(0)
+
+ # Skip empty paths (from failed wikilink conversion)
+ if not img_path:
+ return match.group(0)
+
+ # Handle /api/images/ paths (convert to filesystem paths)
+ if img_path.startswith('/api/images/'):
+ # Strip the /api/images/ prefix to get the relative path within notes_dir
+ relative_path = img_path[len('/api/images/'):]
+ resolved_path = (notes_dir / relative_path).resolve()
+ else:
+ # Try to resolve the image path relative to note folder
+ resolved_path = (note_folder / img_path).resolve()
+
+ # If not found, try the attachment search
+ if not resolved_path.exists():
+ # Extract just the filename and search
+ image_name = Path(img_path).name
+ resolved_path = find_image_in_attachments(image_name, note_folder, notes_dir)
+ if not resolved_path:
+ return match.group(0) # Keep original if not found
+
+ # Security: ensure path is within notes_dir
+ try:
+ resolved_path.relative_to(notes_dir.resolve())
+ except ValueError:
+ # Path is outside notes_dir, skip
+ return match.group(0)
+
+ # Get base64 data
+ base64_url = get_image_as_base64(resolved_path)
+ if base64_url:
+ return f''
+
+ # Image not found, keep original
+ return match.group(0)
+
+ markdown_content = re.sub(img_pattern, replace_image, markdown_content)
+
+ return markdown_content
+
+
+def convert_wikilinks_to_html(markdown_content: str) -> str:
+ """
+ Convert wikilinks [[note]] or [[note|display text]] to HTML links.
+ In standalone export mode, these are non-functional decorative links.
+ """
+ # Pattern for wikilinks: [[target]] or [[target|display text]]
+ # But NOT image wikilinks (those start with !)
+ wikilink_pattern = r'(?{display}'
+
+ return re.sub(wikilink_pattern, replace_wikilink, markdown_content)
+
+
+def generate_export_html(
+ title: str,
+ content: str,
+ theme_css: str,
+ is_dark: bool = False
+) -> str:
+ """
+ Generate a standalone HTML document for a note.
+ Uses marked.js for client-side markdown rendering.
+
+ Args:
+ title: The note title (for and display)
+ content: Raw markdown content (images should already be base64 embedded)
+ theme_css: CSS content for theming
+ is_dark: Whether using a dark theme (for Mermaid/Highlight.js)
+
+ Returns:
+ Complete HTML document as string
+ """
+ # Escape content for JavaScript string
+ escaped_content = (
+ content
+ .replace('\\', '\\\\')
+ .replace('`', '\\`')
+ .replace('$', '\\$')
+ .replace('</', '<\\/') # Prevent </script> breaking
+ )
+
+ highlight_theme = 'github-dark' if is_dark else 'github'
+ mermaid_theme = 'dark' if is_dark else 'default'
+
+ html = f'''<!DOCTYPE html>
+<html lang="en">
+<head>
+ <meta charset="UTF-8">
+ <meta name="viewport" content="width=device-width, initial-scale=1.0">
+ <title>{title}
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