isImageDocumentPath function

bool isImageDocumentPath(String? path)

Whether path points at an image document (vs. a PDF), detected purely by file extension.

This is the shared signal every platform view + headless openDocument uses to decide whether to open the path as an image document. Pass the original document path (e.g. assets/photo.png, /tmp/x.jpg, https://host/img.PNG?token=abc) — query strings and fragments are stripped before the extension is read, and matching is case-insensitive.

Returns false for null/empty paths and for anything without a recognised image extension (PDFs and unknown types load as PDF documents).

Implementation

bool isImageDocumentPath(String? path) {
  if (path == null || path.isEmpty) return false;

  // Drop query/fragment so remote URLs like `img.png?token=…` still match, but
  // only for actual URLs — a local file whose name contains `?` or `#` must
  // keep those characters so its extension is read correctly.
  var cleaned = path;
  if (_hasUrlScheme(cleaned)) {
    final queryIndex = cleaned.indexOf('?');
    if (queryIndex != -1) cleaned = cleaned.substring(0, queryIndex);
    final fragmentIndex = cleaned.indexOf('#');
    if (fragmentIndex != -1) cleaned = cleaned.substring(0, fragmentIndex);
  }

  final dotIndex = cleaned.lastIndexOf('.');
  if (dotIndex == -1 || dotIndex == cleaned.length - 1) return false;

  final extension = cleaned.substring(dotIndex + 1).toLowerCase();
  return kImageDocumentExtensions.contains(extension);
}