Add managed server profiles and account login

dotnet/src/VoiceCat.Core/ServerProfile.cs

@@ -0,0 +1,66 @@
+using System.Text.Json;
+using System.Text.Json.Serialization;
+
+namespace VoiceCat.Core;
+
+public enum ServerAuthentication { Guest, Account }
+
+public sealed record ServerProfile(Guid Id, string Host, ushort Port, ServerAuthentication Authentication, string? Username, string? Nickname)
+{
+    public static ServerProfile Create(string host, ushort port, ServerAuthentication authentication, string? username = null, string? nickname = null, Guid? id = null)
+    {
+        host = host.Trim(); username = Normalize(username); nickname = Normalize(nickname);
+        if (host.Length == 0) throw new ArgumentException("Server host is required.", nameof(host));
+        if (port == 0) throw new ArgumentOutOfRangeException(nameof(port));
+        if (authentication == ServerAuthentication.Account && username is null) throw new ArgumentException("Username is required for account authentication.", nameof(username));
+        return new(id.GetValueOrDefault(Guid.NewGuid()), host, port, authentication,
+            authentication == ServerAuthentication.Account ? username : null,
+            authentication == ServerAuthentication.Guest ? nickname : null);
+    }
+
+    [JsonIgnore]
+    public string DisplayName => Authentication == ServerAuthentication.Account
+        ? $"{Username}@{Host}:{Port}"
+        : $"{Host}:{Port} (Guest{(Nickname is null ? "" : $": {Nickname}")})";
+
+    internal bool IsValid => Id != Guid.Empty && !string.IsNullOrWhiteSpace(Host) && Port != 0 &&
+        (Authentication == ServerAuthentication.Guest || !string.IsNullOrWhiteSpace(Username));
+
+    private static string? Normalize(string? value) => string.IsNullOrWhiteSpace(value) ? null : value.Trim();
+}
+
+public sealed class ServerProfileStore(string path)
+{
+    private static readonly JsonSerializerOptions Json = new()
+    {
+        Converters = { new JsonStringEnumConverter() },
+        PropertyNamingPolicy = JsonNamingPolicy.CamelCase,
+        WriteIndented = true
+    };
+
+    public IReadOnlyList<ServerProfile> Load()
+    {
+        try
+        {
+            if (!File.Exists(path)) return [];
+            return (JsonSerializer.Deserialize<ServerProfile[]>(File.ReadAllBytes(path), Json) ?? [])
+                .Where(profile => profile.IsValid).ToArray();
+        }
+        catch (Exception exception) when (exception is IOException or UnauthorizedAccessException or JsonException) { return []; }
+    }
+
+    public void Save(IEnumerable<ServerProfile> profiles)
+    {
+        ArgumentNullException.ThrowIfNull(profiles);
+        ServerProfile[] valid = profiles.Where(profile => profile is not null && profile.IsValid).ToArray();
+        string fullPath = Path.GetFullPath(path);
+        Directory.CreateDirectory(Path.GetDirectoryName(fullPath)!);
+        string temporary = fullPath + "." + Guid.NewGuid().ToString("N") + ".tmp";
+        try
+        {
+            File.WriteAllBytes(temporary, JsonSerializer.SerializeToUtf8Bytes(valid, Json));
+            File.Move(temporary, fullPath, true);
+        }
+        finally { if (File.Exists(temporary)) File.Delete(temporary); }
+    }
+}