feat(xep): Improve API using enhanced enums

packages/moxxmpp/lib/src/xeps/xep_0300.dart

@@ -4,44 +4,38 @@ import 'package:moxxmpp/src/managers/namespaces.dart';
 import 'package:moxxmpp/src/namespaces.dart';
 import 'package:moxxmpp/src/stringxml.dart';
 
-XMLNode constructHashElement(String algo, String base64Hash) {
+XMLNode constructHashElement(HashFunction hash, String value) {
   return XMLNode.xmlns(
     tag: 'hash',
     xmlns: hashXmlns,
-    attributes: {'algo': algo},
-    text: base64Hash,
+    attributes: {'algo': hash.toName()},
+    text: value,
   );
 }
 
 enum HashFunction {
+  /// SHA-256
   sha256,
+
+  /// SHA-256
   sha512,
+
+  /// SHA3-256
   sha3_256,
+
+  /// SHA3-512
   sha3_512,
+
+  /// BLAKE2b-256
   blake2b256,
-  blake2b512,
-}
 
-extension HashNameToEnumExtension on HashFunction {
-  String toName() {
-    switch (this) {
-      case HashFunction.sha256:
-        return hashSha256;
-      case HashFunction.sha512:
-        return hashSha512;
-      case HashFunction.sha3_256:
-        return hashSha3512;
-      case HashFunction.sha3_512:
-        return hashSha3512;
-      case HashFunction.blake2b256:
-        return hashBlake2b256;
-      case HashFunction.blake2b512:
-        return hashBlake2b512;
-    }
-  }
-}
+  /// BLAKE2b-512
+  blake2b512;
 
-HashFunction hashFunctionFromName(String name) {
+  /// Get a HashFunction from its name [name] according to either
+  /// - IANA's hash name register (http://www.iana.org/assignments/hash-function-text-names/hash-function-text-names.xhtml)
+  /// - XEP-0300
+  factory HashFunction.fromName(String name) {
     switch (name) {
       case hashSha256:
         return HashFunction.sha256;
@@ -58,6 +52,25 @@ HashFunction hashFunctionFromName(String name) {
     }
 
     throw Exception();
+  }
+
+  /// Return the hash function's name according to IANA's hash name register or XEP-0300.
+  String toName() {
+    switch (this) {
+      case HashFunction.sha256:
+        return hashSha256;
+      case HashFunction.sha512:
+        return hashSha512;
+      case HashFunction.sha3_256:
+        return hashSha3512;
+      case HashFunction.sha3_512:
+        return hashSha3512;
+      case HashFunction.blake2b256:
+        return hashBlake2b256;
+      case HashFunction.blake2b512:
+        return hashBlake2b512;
+    }
+  }
 }
 
 class CryptographicHashManager extends XmppManagerBase {

packages/moxxmpp/lib/src/xeps/xep_0446.dart

@@ -13,7 +13,7 @@ class FileMetadataData {
     this.name,
     this.size,
     required this.thumbnails,
-    Map<String, String>? hashes,
+    Map<HashFunction, String>? hashes,
   }) : hashes = hashes ?? const {};
 
   /// Parse [node] as a FileMetadataData element.
@@ -31,9 +31,11 @@ class FileMetadataData {
     final size =
         sizeElement != null ? int.parse(sizeElement.innerText()) : null;
 
-    final hashes = <String, String>{};
+    final hashes = <HashFunction, String>{};
     for (final e in node.findTags('hash')) {
-      hashes[e.attributes['algo']! as String] = e.innerText();
+      final hashFunction =
+          HashFunction.fromName(e.attributes['algo']! as String);
+      hashes[hashFunction] = e.innerText();
     }
 
     // Thumbnails
@@ -75,7 +77,7 @@ class FileMetadataData {
   final int? height;
   final List<Thumbnail> thumbnails;
   final String? desc;
-  final Map<String, String> hashes;
+  final Map<HashFunction, String> hashes;
   final int? length;
   final String? name;
   final int? size;

packages/moxxmpp/lib/src/xeps/xep_0448.dart

@@ -8,23 +8,9 @@ import 'package:moxxmpp/src/xeps/xep_0447.dart';
 enum SFSEncryptionType {
   aes128GcmNoPadding,
   aes256GcmNoPadding,
-  aes256CbcPkcs7,
-}
+  aes256CbcPkcs7;
 
-extension SFSEncryptionTypeNamespaceExtension on SFSEncryptionType {
-  String toNamespace() {
-    switch (this) {
-      case SFSEncryptionType.aes128GcmNoPadding:
-        return sfsEncryptionAes128GcmNoPaddingXmlns;
-      case SFSEncryptionType.aes256GcmNoPadding:
-        return sfsEncryptionAes256GcmNoPaddingXmlns;
-      case SFSEncryptionType.aes256CbcPkcs7:
-        return sfsEncryptionAes256CbcPkcs7Xmlns;
-    }
-  }
-}
-
-SFSEncryptionType encryptionTypeFromNamespace(String xmlns) {
+  factory SFSEncryptionType.fromNamespace(String xmlns) {
     switch (xmlns) {
       case sfsEncryptionAes128GcmNoPaddingXmlns:
         return SFSEncryptionType.aes128GcmNoPadding;
@@ -35,6 +21,18 @@ SFSEncryptionType encryptionTypeFromNamespace(String xmlns) {
     }
 
     throw Exception();
+  }
+
+  String toNamespace() {
+    switch (this) {
+      case SFSEncryptionType.aes128GcmNoPadding:
+        return sfsEncryptionAes128GcmNoPaddingXmlns;
+      case SFSEncryptionType.aes256GcmNoPadding:
+        return sfsEncryptionAes256GcmNoPaddingXmlns;
+      case SFSEncryptionType.aes256CbcPkcs7:
+        return sfsEncryptionAes256CbcPkcs7Xmlns;
+    }
+  }
 }
 
 class StatelessFileSharingEncryptedSource extends StatelessFileSharingSource {
@@ -63,13 +61,15 @@ class StatelessFileSharingEncryptedSource extends StatelessFileSharingSource {
     )!;
 
     // Find hashes
-    final hashes = <String, String>{};
+    final hashes = <HashFunction, String>{};
     for (final hash in element.findTags('hash', xmlns: hashXmlns)) {
-      hashes[hash.attributes['algo']! as String] = hash.text!;
+      final hashFunction =
+          HashFunction.fromName(hash.attributes['algo']! as String);
+      hashes[hashFunction] = hash.text!;
     }
 
     return StatelessFileSharingEncryptedSource(
-      encryptionTypeFromNamespace(element.attributes['cipher']! as String),
+      SFSEncryptionType.fromNamespace(element.attributes['cipher']! as String),
       key,
       iv,
       hashes,
@@ -80,7 +80,7 @@ class StatelessFileSharingEncryptedSource extends StatelessFileSharingSource {
   final List<int> key;
   final List<int> iv;
   final SFSEncryptionType encryption;
-  final Map<String, String> hashes;
+  final Map<HashFunction, String> hashes;
   final StatelessFileSharingUrlSource source;
 
   @override

packages/moxxmpp/lib/src/xeps/xep_0449.dart

@@ -87,7 +87,7 @@ class StickerPack {
     var hashValue = '';
     if (hashAvailable) {
       final hash = node.firstTag('hash', xmlns: hashXmlns)!;
-      hashAlgorithm = hashFunctionFromName(hash.attributes['algo']! as String);
+      hashAlgorithm = HashFunction.fromName(hash.attributes['algo']! as String);
       hashValue = hash.innerText();
     }
 
@@ -144,7 +144,7 @@ class StickerPack {
           text: summary,
         ),
         constructHashElement(
-          hashAlgorithm.toName(),
+          hashAlgorithm,
           hashValue,
         ),
 
@@ -193,7 +193,7 @@ class StickerPack {
       final hashes = List<List<int>>.empty(growable: true);
       for (final hash in sticker.metadata.hashes.keys) {
         hashes.add([
-          ...utf8.encode(hash),
+          ...utf8.encode(hash.toName()),
           0x1f,
           ...utf8.encode(sticker.metadata.hashes[hash]!),
           0x1f,