meshcore-open/lib/helpers/gif_helper.dart
2026-04-09 09:57:46 -07:00

38 lines
1.4 KiB
Dart

class GifHelper {
/// Parse a known GIF format, which can be any of:
/// g:GIFID
/// https://media.giphy.com/media/GIFID/giphy.gif
/// https://giphy.com/gifs/Optional-title-with-dashes-GIFID
///
/// GIFID is a Giphy GIF ID. The https:// is optional (and
/// can also be http://). The giphy.com/gifs form can also
/// include a trailing slash.
///
/// Returns null if text is not a valid GIF format
static String? parseGif(String text) {
final trimmed = text.trim();
final match = RegExp(r'^g:([A-Za-z0-9_-]+)$').firstMatch(trimmed);
if (match != null) {
return match.group(1);
}
final directUrlMatch = RegExp(
r'^(?:https?:\/\/)?media\.giphy\.com\/media\/([A-Za-z0-9_-]+)\/giphy\.gif$',
).firstMatch(trimmed);
if (directUrlMatch != null) {
return directUrlMatch.group(1);
}
// Giphy understands page URLs with just the ID, or any string and a
// dash before the ID, and redirects to a page with a dash-separated
// title, a dash, and the ID. IDs in this form *probably* can't
// contain dashes.
final pageMatch = RegExp(
r'^(?:https?:\/\/)?giphy\.com\/gifs\/(?:[^/?]*-)?([A-Za-z0-9_]+)\/?$',
).firstMatch(trimmed);
return pageMatch?.group(1);
}
/// Encode a GIF in a format that parseGif() can parse.
static String encodeGif(String gifId) {
return 'g:$gifId';
}
}