Files
Relay/RelayClient/MainPage.xaml.cs

568 lines
18 KiB
C#

using RelayClient.Crypto;
using WebSocketSharp;
using System.Text.Json;
using System.Text.Json.Serialization;
using RelayShared.Rtc;
using RelayShared.Services;
namespace RelayClient;
public partial class MainPage : ContentPage
{
private readonly string _username;
private readonly WebSocket _wsc;
private string? _serverPublicKey;
private string? _currentChannelId;
private string? _currentChannelName;
private readonly Dictionary<string, List<ChatMessage>> _messagesByChannel = new();
private readonly List<ChannelItem> _channels = [];
public MainPage(string username)
{
InitializeComponent();
_username = username;
UserLabel.Text = $"Logged in as: {_username}";
if (!KeyStorage.HasKeys(_username))
{
var keys = E2EeHelper.GenerateRsaKeyPair();
KeyStorage.SavePrivateKey(_username, keys.privateKey);
KeyStorage.SavePublicKey(_username, keys.publicKey);
}
_wsc = new WebSocket("ws://localhost:1337/");
_wsc.OnMessage += WscOnMessage;
_wsc.Connect();
var publicKey = KeyStorage.LoadPublicKey(_username);
_wsc.Send($"REGISTER_KEY|{_username}|{publicKey}");
_wsc.Send("GET_SERVER_KEY");
_wsc.Send("GET_CHANNELS");
hybridWebView.SetInvokeJavaScriptTarget(this);
ServerAPI.setupClient();
}
private void SendButton_OnClicked(object? sender, EventArgs e)
{
SendMessage();
}
private void MessageEntry_OnCompleted(object? sender, EventArgs e)
{
SendMessage();
}
private void SendMessage()
{
var text = MessageEntry.Text?.Trim();
if (string.IsNullOrWhiteSpace(text))
return;
if (string.IsNullOrWhiteSpace(_serverPublicKey))
{
Console.WriteLine("Server public key not loaded yet.");
return;
}
if (string.IsNullOrWhiteSpace(_currentChannelId))
{
Console.WriteLine("No channel selected yet.");
return;
}
var encrypted = E2EeHelper.EncryptForRecipient(text, _serverPublicKey);
var payload = new SocketEncryptedMessage
{
ChannelId = _currentChannelId!,
Type = SignalType.ClientEncryptedChat,
SenderUsername = _username,
CipherText = encrypted.CipherText,
Nonce = encrypted.Nonce,
Tag = encrypted.Tag,
EncryptedKey = encrypted.EncryptedKey
};
var json = JsonSerializer.Serialize(payload);
_wsc.Send(json);
Console.WriteLine($"[{_username}] sent encrypted message.");
MessageEntry.Text = string.Empty;
MessageEntry.Focus();
}
private void WscOnMessage(object? sender, MessageEventArgs e)
{
if (e.Data.StartsWith("SERVER:REGISTERED_KEY:"))
{
Console.WriteLine(e.Data);
return;
}
// SafeSendRawToWebView($"[{_username}] RAW WS DATA: {e.Data}");
Console.WriteLine($"[{_username}] RAW WS DATA: {e.Data}");
try
{
using var doc = JsonDocument.Parse(e.Data);
var root = doc.RootElement;
if (!root.TryGetProperty("Type", out var typeElement))
return;
var type = (SignalType)typeElement.GetInt32();
if (type == SignalType.ChannelList)
{
var channelList = JsonSerializer.Deserialize<SocketChannelList>(e.Data);
if (channelList is null)
return;
_channels.Clear();
_channels.AddRange(channelList.Channels.OrderBy(c => c.CreatedAt));
var defaultChannel = _channels
.Where(c => c.Name.Equals("welcome", StringComparison.OrdinalIgnoreCase))
.OrderBy(c => c.CreatedAt)
.FirstOrDefault()
?? _channels.OrderBy(c => c.CreatedAt).FirstOrDefault();
if (defaultChannel is not null)
{
_currentChannelId = defaultChannel.ChannelId;
_currentChannelName = defaultChannel.Name;
MainThread.BeginInvokeOnMainThread(async () =>
{
ChannelLabel.Text = $"#{_currentChannelName}";
RenderChannelList();
await PushRtcContextToJsAsync();
});
_wsc.Send($"GET_HISTORY|{_username}|{_currentChannelId}");
}
return;
}
if (type == SignalType.ServerPublicKey)
{
var serverKeyMessage = JsonSerializer.Deserialize<ServerPublicKeyMessage>(e.Data);
if (serverKeyMessage is not null)
{
_serverPublicKey = serverKeyMessage.PublicKey;
Console.WriteLine($"[{_username}] loaded server public key.");
}
return;
}
if (type == SignalType.EncryptedSignal)
{
var payload = JsonSerializer.Deserialize<SocketRtcSignalMessage>(e.Data);
if (payload is null)
return;
if (payload.ChannelId != _currentChannelId)
return;
if (payload.SenderUsername == _username)
return;
var privateKey = KeyStorage.LoadPrivateKey(_username);
var decryptedJson = E2EeHelper.DecryptForRecipient(
new EncryptedPayload
{
CipherText = payload.CipherText,
Nonce = payload.Nonce,
Tag = payload.Tag,
EncryptedKey = payload.EncryptedKey
},
privateKey
);
var rtcSignal = JsonSerializer.Deserialize<RtcSignalMessage>(decryptedJson);
if (rtcSignal is null)
return;
if (!string.IsNullOrWhiteSpace(rtcSignal.To) &&
!string.Equals(rtcSignal.To, _username, StringComparison.OrdinalIgnoreCase))
{
SafeSendRawToWebView($"Ignoring RTC signal meant for {rtcSignal.To}");
return;
}
SafeSendRawToWebView("Received encrypted RTC signal: " + decryptedJson);
MainThread.BeginInvokeOnMainThread(async () =>
{
await SendRtcSignalToJsAsync(decryptedJson);
});
return;
}
if (type != SignalType.EncryptedChat)
return;
var pyload = JsonSerializer.Deserialize<SocketEncryptedMessage>(e.Data);
if (pyload is null)
return;
if (pyload.RecipientUsername != _username)
return;
Console.WriteLine($"[{_username}] received encrypted payload for {pyload.RecipientUsername}");
var privKey = KeyStorage.LoadPrivateKey(_username);
var decryptedText = E2EeHelper.DecryptForRecipient(
new EncryptedPayload
{
CipherText = pyload.CipherText,
Nonce = pyload.Nonce,
Tag = pyload.Tag,
EncryptedKey = pyload.EncryptedKey
},
privKey
);
Console.WriteLine($"[{_username}] decrypted message from {pyload.SenderUsername}: {decryptedText}");
var message = new ChatMessage
{
SenderUsername = pyload.SenderUsername,
Text = decryptedText,
Timestamp = DateTime.Now
};
if (!_messagesByChannel.ContainsKey(pyload.ChannelId))
{
_messagesByChannel[pyload.ChannelId] = [];
}
_messagesByChannel[pyload.ChannelId].Add(message);
if (pyload.ChannelId == _currentChannelId)
{
MainThread.BeginInvokeOnMainThread(() =>
{
RenderSingleMessage(message);
});
}
}
catch (Exception ex)
{
Console.WriteLine($"[{_username}] failed to process websocket message: {ex.Message}");
}
}
protected override void OnDisappearing()
{
_wsc.OnMessage -= WscOnMessage;
_wsc.Close();
base.OnDisappearing();
}
private void RenderChannelList()
{
SidebarList.Children.Clear();
foreach (var channel in _channels.OrderBy(c => c.CreatedAt))
{
var button = new ChannelButton
{
Text = $"#{channel.Name}",
Type = channel.Type,
Group = channel.Group
};
button.Clicked += (_, _) =>
{
_currentChannelId = channel.ChannelId;
_currentChannelName = channel.Name;
MainThread.BeginInvokeOnMainThread(async () =>
{
await PushRtcContextToJsAsync();
if (channel.Type == ChannelType.Voice)
{
SwapView();
_ = JoinRtcChannel(); //TODO: Join voice calls when clicking channel rather than a separate button
}
});
ChannelLabel.Text = $"#{_currentChannelName}";
RenderCurrentChannelMessages();
if (!_messagesByChannel.ContainsKey(channel.ChannelId))
{
_wsc.Send($"GET_HISTORY|{_username}|{channel.ChannelId}");
}
};
SidebarList.Children.Add(button);
}
}
private void RenderCurrentChannelMessages()
{
MessagesLayout.Children.Clear();
if (_currentChannelId is null)
return;
if (!_messagesByChannel.TryGetValue(_currentChannelId, out var messages))
return;
foreach (var message in messages.OrderBy(m => m.Timestamp))
{
RenderSingleMessage(message);
}
}
private async void RenderSingleMessage(ChatMessage message)
{
bool isOwnMessage = message.SenderUsername == _username;
var bubble = new Border
{
StrokeThickness = 1,
Padding = 10,
Margin = isOwnMessage
? new Thickness(40, 0, 0, 0)
: new Thickness(0, 0, 40, 0),
HorizontalOptions = isOwnMessage
? LayoutOptions.End
: LayoutOptions.Start,
Content = new VerticalStackLayout
{
Spacing = 2,
Children =
{
new Label { Text = message.SenderUsername, FontAttributes = FontAttributes.Bold, FontSize = 12 },
new Label { Text = message.Text, FontSize = 14 },
new Label { Text = message.Timestamp.ToString("h:mm tt"), FontSize = 10 }
}
}
};
MessagesLayout.Children.Add(bubble);
await MessagesScrollView.ScrollToAsync(MessagesLayout, ScrollToPosition.End, true);
}
private void SwapView()
{
if (RtcView.IsVisible)
{
MessagesScrollView.IsVisible = true;
RtcView.IsVisible = false;
ViewSwapped.Text = "Swap to Web View";
}
else
{
MessagesScrollView.IsVisible = false;
RtcView.IsVisible = true;
ViewSwapped.Text = "Swap to Message View";
}
}
private void SwapView_OnClicked(object? sender, EventArgs e)
{
SwapView();
}
#region RTC Functions
public Task JoinRtcChannel()
{
if (string.IsNullOrWhiteSpace(_currentChannelId))
return Task.CompletedTask;
_wsc.Send($"RTC_JOIN_CHANNEL|{_username}|{_currentChannelId}");
return Task.CompletedTask;
}
public void LeaveRtcChannel()
{
if (string.IsNullOrWhiteSpace(_currentChannelId))
return;
_wsc.Send($"RTC_LEAVE_CHANNEL|{_username}|{_currentChannelId}");
}
public void SendRtcSignal(string json)
{
if (string.IsNullOrWhiteSpace(_serverPublicKey))
{
SafeSendRawToWebView("SendRtcSignal failed: server public key not loaded.");
return;
}
RtcSignalMessage? rtcSignal;
try
{
rtcSignal = JsonSerializer.Deserialize<RtcSignalMessage>(json);
}
catch (Exception ex)
{
SafeSendRawToWebView("SendRtcSignal failed to parse RTC signal: " + ex.Message);
return;
}
if (rtcSignal is null)
return;
if (string.IsNullOrWhiteSpace(rtcSignal.ChannelId))
rtcSignal.ChannelId = _currentChannelId;
if (string.IsNullOrWhiteSpace(rtcSignal.From))
rtcSignal.From = _username;
if (string.IsNullOrWhiteSpace(rtcSignal.ChannelId))
{
SafeSendRawToWebView("SendRtcSignal failed: missing channel id.");
return;
}
var outgoingJson = JsonSerializer.Serialize(rtcSignal);
try
{
var encrypted = E2EeHelper.EncryptForRecipient(outgoingJson, _serverPublicKey);
var payload = new SocketRtcSignalMessage
{
Type = SignalType.EncryptedSignal,
SenderUsername = _username,
ChannelId = rtcSignal.ChannelId,
CipherText = encrypted.CipherText,
Nonce = encrypted.Nonce,
Tag = encrypted.Tag,
EncryptedKey = encrypted.EncryptedKey
};
_wsc.Send(JsonSerializer.Serialize(payload));
SafeSendRawToWebView($"SendRtcSignal sent: {rtcSignal.Type} -> {rtcSignal.To}");
}
catch (Exception ex)
{
SafeSendRawToWebView("SendRtcSignal failed: " + ex.Message);
}
}
public async Task<string> GetRtcParticipants()
{
if (string.IsNullOrWhiteSpace(_currentChannelId))
return "[]";
var participants = await ServerAPI.GetRtcParticipantsAsync(_currentChannelId);
return JsonSerializer.Serialize(participants ?? []);
}
private Task SendRtcSignalToJsAsync(string rawJson)
{
MainThread.BeginInvokeOnMainThread(async () =>
{
try
{
var jsArg = JsonSerializer.Serialize(rawJson);
await hybridWebView.EvaluateJavaScriptAsync($@"
try {{
window.HybridWebView.SendRawMessage('C# eval entered');
if (!window.RelaySocket) {{
window.HybridWebView.SendRawMessage('window.RelaySocket missing');
}} else if (typeof window.RelaySocket.receiveRtcSignal !== 'function') {{
window.HybridWebView.SendRawMessage('RelaySocket.receiveRtcSignal missing');
}} else {{
window.HybridWebView.SendRawMessage('Calling RelaySocket.receiveRtcSignal');
window.RelaySocket.receiveRtcSignal({jsArg});
}}
}} catch (err) {{
window.HybridWebView.SendRawMessage('RTC JS dispatch failed: ' + err);
}}
");
}
catch (Exception ex)
{
SafeSendRawToWebView("SendRtcSignalToJsAsync failed: " + ex.Message);
}
});
return Task.CompletedTask;
}
private async Task PushRtcContextToJsAsync()
{
var usernameJson = JsonSerializer.Serialize(_username);
var channelIdJson = JsonSerializer.Serialize(_currentChannelId);
await hybridWebView.EvaluateJavaScriptAsync($"window.setUsername({usernameJson})");
await hybridWebView.EvaluateJavaScriptAsync($"window.setChannelId({channelIdJson})");
Console.WriteLine($"[{_username}] pushed RTC context into HybridWebView.");
}
#endregion
private async void OnHybridWebViewRawMessageReceived(object sender, HybridWebViewRawMessageReceivedEventArgs e)
{
if (e.Message == "rtc_page_ready")
{
await PushRtcContextToJsAsync();
return;
}
SafeSendRawToWebView($"JS RAW -> C#: {e.Message}");
}
private void SafeSendRawToWebView(string message)
{
MainThread.BeginInvokeOnMainThread(() =>
{
try
{
hybridWebView.SendRawMessage(message);
}
catch (Exception ex)
{
Console.WriteLine($"[{_username}] failed to send raw message to HybridWebView: {ex.Message}");
}
});
}
public class ChannelButton : Button
{
public ChannelType Type { get; set; }
public string Group { get; set; }
}
[JsonSourceGenerationOptions(WriteIndented = false)]
[JsonSerializable(typeof(RtcDescription))]
[JsonSerializable(typeof(List<RtcSignalMessage>))]
[JsonSerializable(typeof(IceCandidate))]
[JsonSerializable(typeof(List<IceCandidate>))]
[JsonSerializable(typeof(string))]
internal partial class HybridJSType : JsonSerializerContext
{
// This type's attributes specify JSON serialization info to preserve type structure
// for trimmed builds.
}
}