moxxy/lib/service/helpers.dart

101 lines
2.6 KiB
Dart

import 'dart:io';
import 'dart:ui';
import 'package:flutter/foundation.dart';
import 'package:moxxmpp/moxxmpp.dart';
import 'package:moxxyv2/i18n/strings.g.dart';
import 'package:native_imaging/native_imaging.dart' as native;
Future<String?> _generateBlurhashThumbnailImpl(String path) async {
await native.init();
final bytes = await File(path).readAsBytes();
native.Image image;
int width;
int height;
try {
final dartCodec = await instantiateImageCodec(bytes);
final dartFrame = await dartCodec.getNextFrame();
final rgbaData = await dartFrame.image.toByteData();
if (rgbaData == null) return null;
width = dartFrame.image.width;
height = dartFrame.image.height;
dartFrame.image.dispose();
dartCodec.dispose();
image = native.Image.fromRGBA(
width,
height,
Uint8List.view(
rgbaData.buffer,
rgbaData.offsetInBytes,
rgbaData.lengthInBytes,
),
);
} catch (_) {
// TODO(PapaTutuWawa): Log error
return null;
}
// Scale the image down as recommended by
// https://github.com/woltapp/blurhash#how-fast-is-encoding-decoding
final scaled = image.resample(
20,
(height * (width / height)).toInt(),
native.Transform.bilinear,
);
// Calculate the blurhash
final blurhash = scaled.toBlurhash(3, 3);
// Free resources
image.free();
scaled.free();
return blurhash;
}
/// Generate a blurhash thumbnail using native_imaging.
Future<String?> generateBlurhashThumbnail(String path) async {
return compute(_generateBlurhashThumbnailImpl, path);
}
/// Turn a XmppError into its corresponding translated string.
String xmppErrorToTranslatableString(XmppError error) {
if (error is StartTLSFailedError) {
return t.errors.login.startTlsFailed;
} else if (error is SaslFailedError) {
return t.errors.login.saslFailed;
} else if (error is NoConnectionError) {
return t.errors.login.noConnection;
}
return t.errors.login.unspecified;
}
String getStickerHashKeyType(Map<String, String> hashes) {
if (hashes.containsKey('blake2b-512')) {
return 'blake2b-512';
} else if (hashes.containsKey('blake2b-512')) {
return 'blake2b-256';
} else if (hashes.containsKey('sha3-512')) {
return 'sha3-512';
} else if (hashes.containsKey('sha3-256')) {
return 'sha3-256';
} else if (hashes.containsKey('sha3-256')) {
return 'sha-512';
} else if (hashes.containsKey('sha-256')) {
return 'sha-256';
}
assert(false, 'No valid hash found');
return '';
}
String getStickerHashKey(Map<String, String> hashes) {
final key = getStickerHashKeyType(hashes);
return '$key:${hashes[key]}';
}