feat(chat): enhance chat UI with new features and visual improvements

- Added new attributes for chat colors including rail, date rules, and unread markers.
- Enhanced ChatLine class to support colored segments for continuation lines and horizontal separator rules.
- Introduced a WelcomeBanner class to display a splash screen when no channel is selected.
- Implemented NickColorHelper for deterministic per-nick colors, ensuring consistent user color representation.
- Updated ChannelListSource to highlight channels with unread messages and mentions.
- Improved MainWindow to include a spinner for transitional connection states and display activity in the status bar.
- Added unit tests for NickColorHelper to ensure stable and predictable color indexing.

src/EchoHub.Client/UI/Chat/ChatColors.cs

@@ -21,6 +21,15 @@ public static partial class ChatColors
     public static readonly Attribute AudioAttr = new(new Color(180, 100, 255), Color.None);
     public static readonly Attribute FileAttr = new(new Color(100, 180, 255), Color.None);
 
+    /// <summary>The dim vertical rail (│) separating the nick column from message text.</summary>
+    public static readonly Attribute RailAttr = new(new Color(95, 95, 95), Color.None);
+
+    /// <summary>Horizontal date-separator rules (── Wed, Jul 16 ──…).</summary>
+    public static readonly Attribute DateRuleAttr = new(new Color(120, 120, 120), Color.None);
+
+    /// <summary>The irssi-style "new messages" unread marker rule.</summary>
+    public static readonly Attribute UnreadMarkerAttr = new(new Color(230, 140, 60), Color.None);
+
     /// <summary>
     /// Split text around @mentions and #channels, giving each the appropriate accent color.
     /// Non-special text uses the provided default color.

src/EchoHub.Client/UI/Chat/ChatLine.cs

@@ -23,6 +23,25 @@ public partial class ChatLine
     /// <summary>Number of spaces to prepend on continuation lines when this line is word-wrapped.</summary>
     public int ContinuationIndent { get; set; }
 
+    /// <summary>
+    /// Colored segments to prepend on continuation lines instead of plain spaces
+    /// (e.g. the nick-column rail "                   │ "). When set, takes
+    /// precedence over <see cref="ContinuationIndent"/>.
+    /// </summary>
+    public List<ChatSegment>? ContinuationPrefixSegments { get; set; }
+
+    /// <summary>
+    /// When set, this line is a horizontal separator rule (date change, unread marker).
+    /// The view regenerates it to the current viewport width instead of word-wrapping.
+    /// </summary>
+    public string? RuleLabel { get; set; }
+
+    /// <summary>Color for a rule line; null falls back to <see cref="ChatColors.DateRuleAttr"/>.</summary>
+    public Attribute? RuleAttr { get; set; }
+
+    /// <summary>True for the "new messages" unread-marker rule so it can be removed on channel switch.</summary>
+    public bool IsUnreadMarker { get; set; }
+
     public ChatLine(string plainText)
     {
         Segments = [new ChatSegment(plainText, null)];
@@ -43,9 +62,14 @@ public partial class ChatLine
     /// </summary>
     public List<ChatLine> Wrap(int width, int continuationIndent = 0)
     {
-        if (width <= 0 || TextLength <= width)
+        // Rules are regenerated to viewport width by the view; never word-wrap them.
+        if (RuleLabel is not null || width <= 0 || TextLength <= width)
             return [this];
 
+        var prefixSegments = ContinuationPrefixSegments;
+        if (prefixSegments is not null)
+            continuationIndent = prefixSegments.Sum(s => s.Text.GetColumns());
+
         var tokens = new List<(string grapheme, Attribute? color)>();
         foreach (var segment in Segments)
             foreach (var g in GraphemeHelper.GetGraphemes(segment.Text))
@@ -91,8 +115,13 @@ public partial class ChatLine
             }
 
             var segments = new List<ChatSegment>();
-            if (!firstLine && continuationIndent > 0)
+            if (!firstLine)
+            {
+                if (prefixSegments is not null)
+                    segments.AddRange(prefixSegments);
+                else if (continuationIndent > 0)
                     segments.Add(new ChatSegment(new string(' ', continuationIndent), null));
+            }
 
             // Rebuild segments by grouping consecutive same-color tokens.
             var sb = new StringBuilder();
@@ -120,6 +149,7 @@ public partial class ChatLine
             return [this];
 
         // Propagate metadata to all wrapped lines so they remain clickable
+        // and keep the mention highlight across continuation lines
         foreach (var wrapped in results)
         {
             wrapped.AttachmentUrl = AttachmentUrl;
@@ -127,6 +157,7 @@ public partial class ChatLine
             wrapped.AttachmentKind = AttachmentKind;
             wrapped.MessageId = MessageId;
             wrapped.SenderUsername = SenderUsername;
+            wrapped.IsMention = IsMention;
         }
 
         return results;

src/EchoHub.Client/UI/Chat/ChatMessageManager.cs

@@ -1,3 +1,4 @@
+using System.Text;
 using System.Text.RegularExpressions;
 using EchoHub.Client.UI.Helpers;
 using EchoHub.Core.DTOs;
@@ -15,8 +16,18 @@ namespace EchoHub.Client.UI.Chat;
 /// </summary>
 public sealed class ChatMessageManager
 {
+    /// <summary>Columns reserved for the right-aligned nick column (WeeChat-style).</summary>
+    public const int NickColWidth = 12;
+
+    /// <summary>Columns before message text starts: "HH:mm " + nick column + " │ ".</summary>
+    public const int ContentIndentCols = 6 + NickColWidth + 3;
+
     private readonly Dictionary<string, List<ChatLine>> _channelMessages = [];
     private readonly Dictionary<string, int> _channelUnread = [];
+    private readonly Dictionary<string, DateTime> _channelLastDate = [];
+    private readonly HashSet<string> _markedChannels = [];
+    private readonly Dictionary<string, Guid> _markerAnchor = [];
+    private readonly HashSet<string> _mentionChannels = [];
 
     private string _currentUser = string.Empty;
     private string _currentChannel = string.Empty;
@@ -33,7 +44,16 @@ public sealed class ChatMessageManager
     public string CurrentChannel
     {
         get => _currentChannel;
-        set => _currentChannel = value;
+        set
+        {
+            if (_currentChannel == value)
+                return;
+
+            // Leaving a channel consumes its "new messages" marker so the next
+            // unread burst gets a fresh one (irssi behavior).
+            RemoveUnreadMarker(_currentChannel);
+            _currentChannel = value;
+        }
     }
 
     public string CurrentUser => _currentUser;
@@ -57,10 +77,14 @@ public sealed class ChatMessageManager
     public void ClearUnread(string channelName)
     {
         _channelUnread[channelName] = 0;
+        _mentionChannels.Remove(channelName);
     }
 
     internal Dictionary<string, int> GetUnreadCounts() => _channelUnread;
 
+    /// <summary>Channels with an unread @mention of the current user (cleared by <see cref="ClearUnread"/>).</summary>
+    public IReadOnlySet<string> MentionChannels => _mentionChannels;
+
     // ── Mutations ────────────────────────────────────────────────────
 
     /// <summary>
@@ -75,19 +99,36 @@ public sealed class ChatMessageManager
             _channelMessages[message.ChannelName] = messages;
         }
 
+        // Day boundary → horizontal date rule
+        var msgDate = message.SentAt.ToLocalTime().Date;
+        if (!_channelLastDate.TryGetValue(message.ChannelName, out var lastDate) || lastDate != msgDate)
+        {
+            messages.Add(DateRule(msgDate));
+            _channelLastDate[message.ChannelName] = msgDate;
+        }
+
+        var isCurrent = message.ChannelName == _currentChannel;
+
+        // First unread message in an inactive channel → "new messages" marker,
+        // anchored to this message so a history reload can re-place it
+        if (!isCurrent && _markedChannels.Add(message.ChannelName))
+        {
+            messages.Add(UnreadMarkerRule());
+            _markerAnchor[message.ChannelName] = message.Id;
+        }
+
         foreach (var line in lines)
             messages.Add(line);
 
-        if (message.ChannelName == _currentChannel)
+        if (!isCurrent)
-        {
-            MessagesChanged?.Invoke(message.ChannelName);
-        }
-        else
         {
             _channelUnread.TryGetValue(message.ChannelName, out var count);
             _channelUnread[message.ChannelName] = count + 1;
-            MessagesChanged?.Invoke(message.ChannelName);
+            if (lines.Any(l => l.IsMention))
+                _mentionChannels.Add(message.ChannelName);
         }
+
+        MessagesChanged?.Invoke(message.ChannelName);
     }
 
     /// <summary>
@@ -101,24 +142,20 @@ public sealed class ChatMessageManager
             _channelMessages[channelName] = messages;
         }
 
-        var time = FormatDateTime(DateTimeOffset.Now);
+        var time = FormatTime(DateTimeOffset.Now);
         var textLines = text.Split('\n');
 
-        messages.Add(new ChatLine(
+        var header = SystemHeaderSegments(time);
-        [
+        header.Add(new(textLines[0].TrimEnd('\r'), ChatColors.SystemAttr));
-            new($"[{time}] ", ChatColors.TimestampAttr),
+        messages.Add(new ChatLine(header) { ContinuationPrefixSegments = RailPrefix() });
-            new($"** {textLines[0].TrimEnd('\r')}", ChatColors.SystemAttr)
-        ]));
 
-        var indent = new string(' ', $"[{time}] ** ".Length);
         for (int i = 1; i < textLines.Length; i++)
         {
             var line = textLines[i].TrimEnd('\r');
             if (string.IsNullOrWhiteSpace(line)) continue;
-            messages.Add(new ChatLine(
+            var segments = RailPrefix();
-            [
+            segments.Add(new(line, ChatColors.SystemAttr));
-                new($"{indent}{line}", ChatColors.SystemAttr)
+            messages.Add(new ChatLine(segments) { ContinuationPrefixSegments = RailPrefix() });
-            ]));
         }
 
         if (channelName == _currentChannel)
@@ -130,19 +167,16 @@ public sealed class ChatMessageManager
     /// </summary>
     public void AddStatusMessage(string channelName, string username, string status)
     {
-        var time = FormatDateTime(DateTimeOffset.Now);
+        var time = FormatTime(DateTimeOffset.Now);
-        var segments = new List<ChatSegment>
+        var segments = SystemHeaderSegments(time);
-        {
+        segments.Add(new($"{username} is now {status}", ChatColors.SystemAttr));
-            new($"[{time}] ", ChatColors.TimestampAttr),
-            new($"** {username} is now {status}", ChatColors.SystemAttr)
-        };
 
         if (!_channelMessages.TryGetValue(channelName, out var messages))
         {
             messages = [];
             _channelMessages[channelName] = messages;
         }
-        messages.Add(new ChatLine(segments));
+        messages.Add(new ChatLine(segments) { ContinuationPrefixSegments = RailPrefix() });
 
         if (channelName == _currentChannel)
             MessagesChanged?.Invoke(channelName);
@@ -169,6 +203,9 @@ public sealed class ChatMessageManager
         if (_channelMessages.TryGetValue(channelName, out var messages))
         {
             messages.Clear();
+            _channelLastDate.Remove(channelName);
+            _markedChannels.Remove(channelName);
+            _markerAnchor.Remove(channelName);
             if (channelName == _currentChannel)
                 MessagesChanged?.Invoke(channelName);
         }
@@ -179,9 +216,35 @@ public sealed class ChatMessageManager
     /// </summary>
     public void LoadHistory(string channelName, List<MessageDto> messages)
     {
-        var formatted = messages.SelectMany(FormatMessage).ToList();
+        var formatted = FormatWithDateRules(messages, out var lastDate);
+
+        // Re-place the "new messages" marker at its anchor — channel selection
+        // reloads history, which would otherwise wipe the marker right when the
+        // user switches in to read the unread backlog.
+        if (_markedChannels.Contains(channelName))
+        {
+            var anchorIdx = _markerAnchor.TryGetValue(channelName, out var anchorId)
+                ? formatted.FindIndex(l => l.MessageId == anchorId)
+                : -1;
+            if (anchorIdx >= 0)
+            {
+                formatted.Insert(anchorIdx, UnreadMarkerRule());
+            }
+            else
+            {
+                // Anchor fell outside the fetched history window — drop the marker
+                _markedChannels.Remove(channelName);
+                _markerAnchor.Remove(channelName);
+            }
+        }
+
         _channelMessages[channelName] = formatted;
 
+        if (lastDate is { } date)
+            _channelLastDate[channelName] = date;
+        else
+            _channelLastDate.Remove(channelName);
+
         if (channelName == _currentChannel)
             MessagesChanged?.Invoke(channelName);
     }
@@ -200,14 +263,23 @@ public sealed class ChatMessageManager
             .Select(l => l.MessageId!.Value)
             .ToHashSet();
 
-        var newLines = olderMessages
+        var fresh = olderMessages.Where(m => !existingIds.Contains(m.Id)).ToList();
-            .Where(m => !existingIds.Contains(m.Id))
+        var newLines = FormatWithDateRules(fresh, out var lastBatchDate);
-            .SelectMany(FormatMessage)
-            .ToList();
 
         if (newLines.Count == 0)
             return;
 
+        // The buffer's leading date rule is redundant when the prepended batch
+        // ends on the same day — the batch already carries that day's rule.
+        if (lastBatchDate is { } batchDate
+            && existing.Count > 0
+            && existing[0].RuleLabel is { } label
+            && !existing[0].IsUnreadMarker
+            && label == DateRuleLabel(batchDate))
+        {
+            existing.RemoveAt(0);
+        }
+
         existing.InsertRange(0, newLines);
 
         if (channelName == _currentChannel)
@@ -226,6 +298,10 @@ public sealed class ChatMessageManager
     {
         _channelMessages.Clear();
         _channelUnread.Clear();
+        _channelLastDate.Clear();
+        _markedChannels.Clear();
+        _markerAnchor.Clear();
+        _mentionChannels.Clear();
         _currentChannel = string.Empty;
         _currentUser = string.Empty;
     }
@@ -234,12 +310,9 @@ public sealed class ChatMessageManager
 
     private List<ChatLine> FormatMessage(MessageDto message)
     {
-        var time = FormatDateTime(message.SentAt);
+        var time = FormatTime(message.SentAt);
-        var senderName = message.SenderUsername + ":";
+        var senderColor = HexColorHelper.ParseHexColor(message.SenderNicknameColor)
-        var senderColor = HexColorHelper.ParseHexColor(message.SenderNicknameColor);
+            ?? NickColorHelper.GetAttribute(message.SenderUsername);
-
-        var indent = new string(' ', $"[{time}] {senderName} ".Length);
-        var pad = new string(' ', 7);
 
         var lines = new List<ChatLine>();
         var hasContent = !string.IsNullOrWhiteSpace(message.Content);
@@ -250,9 +323,17 @@ public sealed class ChatMessageManager
         {
             var displayContent = EmojiHelper.ReplaceEmoji(message.Content);
             var contentLines = displayContent.Split('\n');
-            lines.Add(BuildChatLineWithMentions(time, senderName, senderColor, $" {contentLines[0].TrimEnd('\r')}"));
+
+            var header = HeaderSegments(time, message.SenderUsername, senderColor);
+            header.AddRange(ChatColors.SplitMentions(contentLines[0].TrimEnd('\r')));
+            lines.Add(new ChatLine(header));
+
             for (int i = 1; i < contentLines.Length; i++)
-                lines.Add(new ChatLine(ChatColors.SplitMentions($"{indent}{contentLines[i].TrimEnd('\r')}")));
+            {
+                var segments = RailPrefix();
+                segments.AddRange(ChatColors.SplitMentions(contentLines[i].TrimEnd('\r')));
+                lines.Add(new ChatLine(segments));
+            }
         }
         else
         {
@@ -262,13 +343,15 @@ public sealed class ChatMessageManager
                 1 => $"[{attachments[0].Kind.ToString().ToLowerInvariant()}]",
                 _ => $"[{attachments.Count} attachments]",
             };
-            lines.Add(BuildChatLine(time, senderName, senderColor, summary));
+            var header = HeaderSegments(time, message.SenderUsername, senderColor);
+            header.Add(new(summary, null));
+            lines.Add(new ChatLine(header));
         }
 
         foreach (var l in lines)
-            l.ContinuationIndent = indent.Length;
+            l.ContinuationPrefixSegments = RailPrefix();
 
-        // One block per attachment
+        // One block per attachment — every block hangs off the nick-column rail
         foreach (var attachment in attachments)
         {
             switch (attachment.Kind)
@@ -279,24 +362,27 @@ public sealed class ChatMessageManager
                         foreach (var artLine in attachment.AsciiPreview.Split('\n'))
                         {
                             var trimmed = artLine.TrimEnd('\r');
-                            lines.Add(ChatLine.HasColorTags(trimmed)
+                            var segments = RailPrefix();
-                                ? ChatLine.FromColoredText(pad + trimmed)
+                            if (ChatLine.HasColorTags(trimmed))
-                                : new ChatLine($"{pad}{trimmed}"));
+                                segments.AddRange(ChatLine.FromColoredText(trimmed).Segments);
+                            else
+                                segments.Add(new(trimmed, null));
+                            lines.Add(new ChatLine(segments));
                         }
                     }
-                    lines.Add(AttachmentActionLine(pad,
+                    lines.Add(AttachmentActionLine(
                         $"[↓ save original] {attachment.FileName} [{FormatFileSize(attachment.FileSize)}]",
                         ChatColors.FileAttr, attachment));
                     break;
 
                 case Core.Models.AttachmentKind.Audio:
-                    lines.Add(AttachmentActionLine(pad,
+                    lines.Add(AttachmentActionLine(
                         $"♪ [Audio: {attachment.FileName}] [{FormatFileSize(attachment.FileSize)}]",
                         ChatColors.AudioAttr, attachment));
                     break;
 
                 default:
-                    lines.Add(AttachmentActionLine(pad,
+                    lines.Add(AttachmentActionLine(
                         $"[File: {attachment.FileName}] [{FormatFileSize(attachment.FileSize)}]",
                         ChatColors.FileAttr, attachment));
                     break;
@@ -308,7 +394,7 @@ public sealed class ChatMessageManager
         {
             var chatWidth = _chatWidth > 0 ? _chatWidth : 80;
             foreach (var embed in message.Embeds)
-                lines.AddRange(FormatEmbed(embed, indent, chatWidth));
+                lines.AddRange(FormatEmbed(embed, chatWidth));
         }
 
         foreach (var line in lines)
@@ -334,71 +420,142 @@ public sealed class ChatMessageManager
     /// Builds a clickable attachment line carrying the metadata the message list uses to
     /// route activation (play audio, download file, save original image).
     /// </summary>
-    private static ChatLine AttachmentActionLine(string pad, string text, Attribute color, AttachmentDto attachment)
+    private static ChatLine AttachmentActionLine(string text, Attribute color, AttachmentDto attachment)
     {
-        var line = new ChatLine(new List<ChatSegment>
+        var segments = RailPrefix();
+        segments.Add(new(text, color));
+        return new ChatLine(segments)
         {
-            new(pad, null),
+            AttachmentUrl = attachment.Url,
-            new(text, color),
+            AttachmentFileName = attachment.FileName,
-        });
+            AttachmentKind = attachment.Kind,
-        line.AttachmentUrl = attachment.Url;
+            ContinuationPrefixSegments = RailPrefix(),
-        line.AttachmentFileName = attachment.FileName;
-        line.AttachmentKind = attachment.Kind;
-        return line;
-    }
-
-    private static ChatLine BuildChatLine(string time, string senderName, Attribute? senderColor, string suffix)
-    {
-        var segments = new List<ChatSegment>
-        {
-            new($"[{time}] ", ChatColors.TimestampAttr),
-            new(senderName, senderColor),
-            new(suffix, null)
         };
-        return new ChatLine(segments);
     }
 
-    private static ChatLine BuildChatLineColored(string time, string senderName, Attribute? senderColor, string suffix, Attribute suffixColor)
+    /// <summary>
+    /// Leading segments of a message header line: dim "HH:mm ", the right-aligned
+    /// nick column, and the " │ " rail. Message text follows at <see cref="ContentIndentCols"/>.
+    /// </summary>
+    private static List<ChatSegment> HeaderSegments(string time, string nick, Attribute? nickColor) =>
+    [
+        new($"{time} ", ChatColors.TimestampAttr),
+        new(PadNick(nick), nickColor),
+        new(" │ ", ChatColors.RailAttr),
+    ];
+
+    /// <summary>Header variant for system/status lines: "--" in the nick column.</summary>
+    private static List<ChatSegment> SystemHeaderSegments(string time) =>
+    [
+        new($"{time} ", ChatColors.TimestampAttr),
+        new(PadNick("--"), ChatColors.TimestampAttr),
+        new(" │ ", ChatColors.RailAttr),
+    ];
+
+    /// <summary>
+    /// Indent segments aligning continuation/attachment/embed lines under the message
+    /// text, extending the │ rail. Returns a fresh mutable list each call.
+    /// </summary>
+    private static List<ChatSegment> RailPrefix() =>
+    [
+        new(new string(' ', 6 + NickColWidth + 1), null),
+        new("│ ", ChatColors.RailAttr),
+    ];
+
+    /// <summary>
+    /// Right-aligns a nick into the fixed nick column, truncating over-long nicks
+    /// with an ellipsis. Grapheme/column aware.
+    /// </summary>
+    internal static string PadNick(string nick)
     {
-        var segments = new List<ChatSegment>
+        var cols = nick.GetColumns();
+        if (cols > NickColWidth)
         {
-            new($"[{time}] ", ChatColors.TimestampAttr),
+            var sb = new StringBuilder();
-            new(senderName, senderColor),
+            int used = 0;
-            new(suffix, suffixColor)
+            foreach (var g in GraphemeHelper.GetGraphemes(nick))
+            {
+                var gCols = Math.Max(g.GetColumns(), 1);
+                if (used + gCols > NickColWidth - 1) break;
+                sb.Append(g);
+                used += gCols;
+            }
+            sb.Append('…');
+            nick = sb.ToString();
+            cols = used + 1;
+        }
+        return new string(' ', NickColWidth - cols) + nick;
+    }
+
+    internal static string DateRuleLabel(DateTime date) => date.ToString("ddd, MMM d yyyy");
+
+    private static ChatLine DateRule(DateTime date)
+    {
+        var label = DateRuleLabel(date);
+        return new ChatLine([new($"── {label} ──", ChatColors.DateRuleAttr)])
+        {
+            RuleLabel = label,
+            RuleAttr = ChatColors.DateRuleAttr,
         };
-        return new ChatLine(segments);
     }
 
-    private static ChatLine BuildChatLineWithMentions(string time, string senderName, Attribute? senderColor, string suffix)
+    private static ChatLine UnreadMarkerRule() =>
+        new([new("── new messages ──", ChatColors.UnreadMarkerAttr)])
         {
-        var segments = new List<ChatSegment>
+            RuleLabel = "new messages",
-        {
+            RuleAttr = ChatColors.UnreadMarkerAttr,
-            new($"[{time}] ", ChatColors.TimestampAttr),
+            IsUnreadMarker = true,
-            new(senderName, senderColor),
         };
-        segments.AddRange(ChatColors.SplitMentions(suffix));
+
-        return new ChatLine(segments);
+    private void RemoveUnreadMarker(string channel)
+    {
+        if (string.IsNullOrEmpty(channel) || !_markedChannels.Remove(channel))
+            return;
+
+        _markerAnchor.Remove(channel);
+        if (_channelMessages.TryGetValue(channel, out var messages))
+            messages.RemoveAll(l => l.IsUnreadMarker);
     }
 
-    private static List<ChatLine> FormatEmbed(EmbedDto embed, string indent, int chatWidth)
+    /// <summary>
+    /// Formats a chronological batch of messages, inserting a date rule before the
+    /// first message and at every day boundary. Outputs the batch's last local date.
+    /// </summary>
+    private List<ChatLine> FormatWithDateRules(List<MessageDto> messages, out DateTime? lastDate)
+    {
+        var lines = new List<ChatLine>();
+        lastDate = null;
+
+        foreach (var message in messages)
+        {
+            var date = message.SentAt.ToLocalTime().Date;
+            if (lastDate != date)
+            {
+                lines.Add(DateRule(date));
+                lastDate = date;
+            }
+            lines.AddRange(FormatMessage(message));
+        }
+
+        return lines;
+    }
+
+    private static List<ChatLine> FormatEmbed(EmbedDto embed, int chatWidth)
     {
         var lines = new List<ChatLine>();
         const string border = "\u258f "; // ▏ + space
         const int borderCols = 2;
-        int indentCols = indent.GetColumns();
+        int textWidth = chatWidth - ContentIndentCols - borderCols;
-        int textWidth = chatWidth - indentCols - borderCols;
         if (textWidth < 20) textWidth = 20;
 
         var borderAttr = HexColorHelper.ParseHexColor(embed.ThemeColor) ?? ChatColors.EmbedBorderAttr;
 
         void AddTextLine(string text, Attribute? color)
         {
-            lines.Add(new ChatLine(
+            var segments = RailPrefix();
-            [
+            segments.Add(new ChatSegment(border, borderAttr));
-                new ChatSegment(indent, null),
+            segments.Add(new ChatSegment(text, color));
-                new ChatSegment(border, borderAttr),
+            lines.Add(new ChatLine(segments));
-                new ChatSegment(text, color)
-            ]));
         }
 
         if (!string.IsNullOrWhiteSpace(embed.SiteName))
@@ -449,20 +606,11 @@ public sealed class ChatMessageManager
         return result;
     }
 
-    private static string FormatDateTime(DateTimeOffset timestamp)
+    // Timestamps are compact HH:mm — the calendar day is carried by date rules,
-    {
+    // inserted at every local-day boundary. Convert to local first so a message
-        // Server timestamps arrive in UTC; convert to local before deciding the calendar day,
+    // near midnight lands under the right date rule.
-        // otherwise a "today" message near midnight is misclassified against the local date.
+    private static string FormatTime(DateTimeOffset timestamp) =>
-        var local = timestamp.ToLocalTime();
+        timestamp.ToLocalTime().ToString("HH:mm");
-
-        // Today's messages show a compact date + short time; older messages fall back to the
-        // culture's general short date/time. Both always include the date so new messages
-        // are never left date-less.
-        if (local.Date == DateTimeOffset.Now.Date)
-            return $"{local:d} {local:t}";
-
-        return local.ToString("g");
-    }
 
     internal static string FormatFileSize(long? bytes)
     {

src/EchoHub.Client/UI/Chat/WelcomeBanner.cs

@@ -0,0 +1,103 @@
+using Terminal.Gui.Drawing;
+using Terminal.Gui.Text;
+using Attribute = Terminal.Gui.Drawing.Attribute;
+
+namespace EchoHub.Client.UI.Chat;
+
+/// <summary>
+/// The MOTD-style splash rendered into the chat pane when no channel is selected —
+/// a gold-gradient ASCII logo with version and key hints, in the spirit of classic
+/// IRC client greetings.
+/// </summary>
+internal static class WelcomeBanner
+{
+    // "ECHOHUB" in FIGlet ANSI-Shadow (58 columns)
+    private static readonly string[] BigLogo =
+    [
+        "███████╗ ██████╗██╗  ██╗ ██████╗ ██╗  ██╗██╗   ██╗██████╗ ",
+        "██╔════╝██╔════╝██║  ██║██╔═══██╗██║  ██║██║   ██║██╔══██╗",
+        "█████╗  ██║     ███████║██║   ██║███████║██║   ██║██████╔╝",
+        "██╔══╝  ██║     ██╔══██║██║   ██║██╔══██║██║   ██║██╔══██╗",
+        "███████╗╚██████╗██║  ██║╚██████╔╝██║  ██║╚██████╔╝██████╔╝",
+        "╚══════╝ ╚═════╝╚═╝  ╚═╝ ╚═════╝ ╚═╝  ╚═╝ ╚═════╝ ╚═════╝ ",
+    ];
+
+    // Compact box-drawing fallback for narrow panes (21 columns)
+    private static readonly string[] SmallLogo =
+    [
+        "┌─┐┌─┐┬ ┬┌─┐┬ ┬┬ ┬┌┐ ",
+        "├┤ │  ├─┤│ │├─┤│ │├┴┐",
+        "└─┘└─┘┴ ┴└─┘┴ ┴└─┘└─┘",
+    ];
+
+    // Vertical gold gradient, bright at the top fading to bronze — matches the
+    // EchoHub brand color used in the status bar.
+    private static readonly Color[] Gradient =
+    [
+        new(255, 215, 105),
+        new(245, 199, 89),
+        new(232, 183, 74),
+        new(216, 165, 60),
+        new(198, 146, 48),
+        new(178, 128, 38),
+    ];
+
+    private static readonly Attribute HintKeyAttr = new(new Color(140, 170, 200), Color.None);
+    private static readonly Attribute HintTextAttr = new(new Color(120, 120, 120), Color.None);
+    private static readonly Attribute TaglineAttr = new(new Color(160, 160, 160), Color.None);
+
+    private static readonly (string Key, string Hint)[] Hints =
+    [
+        ("Server → Connect", "join a server"),
+        ("Ctrl+K          ", "search channels & users"),
+        ("F2              ", "toggle the users panel"),
+        ("/help           ", "all commands"),
+    ];
+
+    /// <summary>
+    /// Builds banner lines centered for the given viewport width.
+    /// </summary>
+    public static List<ChatLine> Build(int width, string version)
+    {
+        var logo = width >= BigLogo[0].GetColumns() + 2 ? BigLogo : SmallLogo;
+        int logoWidth = logo[0].GetColumns();
+        var pad = new string(' ', Math.Max((width - logoWidth) / 2, 0));
+
+        var lines = new List<ChatLine> { new(""), new("") };
+
+        for (int i = 0; i < logo.Length; i++)
+        {
+            // Scale the gradient across however many rows the chosen logo has
+            var color = Gradient[Math.Min(i * Gradient.Length / logo.Length, Gradient.Length - 1)];
+            lines.Add(new ChatLine([
+                new ChatSegment(pad, null),
+                new ChatSegment(logo[i], new Attribute(color, Color.None)),
+            ]));
+        }
+
+        lines.Add(new ChatLine(""));
+
+        var tagline = $"v{version} — terminal chat with that old IRC soul";
+        lines.Add(Centered(tagline, width, TaglineAttr));
+        lines.Add(new ChatLine(""));
+
+        int hintWidth = Hints.Max(h => h.Key.Length + 2 + h.Hint.Length);
+        var hintPad = new string(' ', Math.Max((width - hintWidth) / 2, 0));
+        foreach (var (key, hint) in Hints)
+        {
+            lines.Add(new ChatLine([
+                new ChatSegment(hintPad, null),
+                new ChatSegment(key, HintKeyAttr),
+                new ChatSegment("  " + hint, HintTextAttr),
+            ]));
+        }
+
+        return lines;
+    }
+
+    private static ChatLine Centered(string text, int width, Attribute attr)
+    {
+        var pad = new string(' ', Math.Max((width - text.GetColumns()) / 2, 0));
+        return new ChatLine([new ChatSegment(pad, null), new ChatSegment(text, attr)]);
+    }
+}

src/EchoHub.Client/UI/Helpers/NickColorHelper.cs

@@ -0,0 +1,60 @@
+using Terminal.Gui.Drawing;
+using Attribute = Terminal.Gui.Drawing.Attribute;
+
+namespace EchoHub.Client.UI.Helpers;
+
+/// <summary>
+/// Deterministic per-nick colors for users who haven't picked a nickname color.
+/// The same nick always maps to the same palette entry (classic IRC client behavior),
+/// so a busy channel stays scannable without any configuration.
+/// </summary>
+public static class NickColorHelper
+{
+    // Medium-saturation truecolor values chosen to stay readable on both dark and
+    // light backgrounds. Order matters: changing it re-colors everyone.
+    private static readonly Attribute[] Palette =
+    [
+        new(new Color(224, 108, 117), Color.None), // soft red
+        new(new Color(152, 195, 121), Color.None), // green
+        new(new Color(229, 192, 123), Color.None), // sand
+        new(new Color(97, 175, 239), Color.None),  // blue
+        new(new Color(198, 120, 221), Color.None), // magenta
+        new(new Color(86, 182, 194), Color.None),  // teal
+        new(new Color(255, 160, 122), Color.None), // salmon
+        new(new Color(130, 170, 255), Color.None), // periwinkle
+        new(new Color(195, 232, 141), Color.None), // lime
+        new(new Color(137, 221, 255), Color.None), // sky
+        new(new Color(255, 203, 107), Color.None), // amber
+        new(new Color(240, 130, 170), Color.None), // rose
+    ];
+
+    /// <summary>
+    /// Stable palette index for a nick: case-insensitive FNV-1a over the nick,
+    /// reduced modulo <paramref name="paletteSize"/>. Pure function (no Terminal.Gui
+    /// types) so it is unit-testable without a display driver.
+    /// </summary>
+    public static int GetPaletteIndex(string nick, int paletteSize)
+    {
+        if (paletteSize <= 0)
+            return 0;
+
+        const uint fnvOffset = 2166136261;
+        const uint fnvPrime = 16777619;
+
+        uint hash = fnvOffset;
+        foreach (var ch in nick)
+        {
+            hash ^= char.ToLowerInvariant(ch);
+            hash *= fnvPrime;
+        }
+
+        return (int)(hash % (uint)paletteSize);
+    }
+
+    /// <summary>
+    /// The color attribute for a nick. Used as a fallback when the user has no
+    /// explicit nickname color set.
+    /// </summary>
+    public static Attribute GetAttribute(string nick) =>
+        Palette[GetPaletteIndex(nick, Palette.Length)];
+}

src/EchoHub.Client/UI/ListSources/ChannelListSource.cs

@@ -17,6 +17,7 @@ public class ChannelListSource : IListDataSource
     private readonly List<string> _channelNames = [];
     private readonly Dictionary<string, int> _unreadCounts = [];
     private readonly HashSet<string> _protectedChannels = [];
+    private readonly HashSet<string> _mentionChannels = [];
     private string _activeChannel = string.Empty;
 
     public event NotifyCollectionChangedEventHandler? CollectionChanged;
@@ -28,9 +29,10 @@ public class ChannelListSource : IListDataSource
     private static readonly Attribute UnreadAttr = new(Color.BrightCyan, Color.None);
     private static readonly Attribute NormalAttr = new(Color.DarkGray, Color.None);
     private static readonly Attribute BadgeAttr = new(Color.BrightYellow, Color.None);
+    private static readonly Attribute MentionAttr = new(new Color(230, 140, 60), Color.None);
 
     public void Update(List<string> channels, Dictionary<string, int> unread, string activeChannel,
-        IReadOnlySet<string>? protectedChannels = null)
+        IReadOnlySet<string>? protectedChannels = null, IReadOnlySet<string>? mentionChannels = null)
     {
         _channelNames.Clear();
         _channelNames.AddRange(channels);
@@ -40,6 +42,9 @@ public class ChannelListSource : IListDataSource
         _protectedChannels.Clear();
         if (protectedChannels is not null)
             _protectedChannels.UnionWith(protectedChannels);
+        _mentionChannels.Clear();
+        if (mentionChannels is not null)
+            _mentionChannels.UnionWith(mentionChannels);
         _activeChannel = activeChannel;
         MaxItemLength = channels.Count > 0 ? channels.Max(c => c.Length + 6) : 0;
         if (!SuspendCollectionChangedEvent)
@@ -82,12 +87,18 @@ public class ChannelListSource : IListDataSource
             listView.SetAttribute(Resolve(isActive ? ActiveAttr : NormalAttr));
             drawnChars = RenderHelpers.WriteText(listView, prefix, drawnChars, width);
 
-            listView.SetAttribute(Resolve(isActive ? ActiveAttr : hasUnread ? UnreadAttr : NormalAttr));
+            // Mentions escalate above plain unread: the whole entry turns orange
+            var hasMention = _mentionChannels.Contains(name);
+            var nameAttr = isActive ? ActiveAttr
+                : hasMention ? MentionAttr
+                : hasUnread ? UnreadAttr
+                : NormalAttr;
+            listView.SetAttribute(Resolve(nameAttr));
             drawnChars = RenderHelpers.WriteText(listView, channelText, drawnChars, width);
 
             if (hasUnread)
             {
-                listView.SetAttribute(Resolve(BadgeAttr));
+                listView.SetAttribute(Resolve(hasMention ? MentionAttr : BadgeAttr));
                 drawnChars = RenderHelpers.WriteText(listView, badge, drawnChars, width);
             }
         }

src/EchoHub.Client/UI/MainWindow.cs

@@ -319,6 +319,12 @@ public sealed partial class MainWindow : Runnable
         _statusLabel.DrawingContent += OnStatusBarDrawContent;
         Add(_statusLabel);
 
+        // Rounded borders for a softer, modern frame look
+        channelsFrame.BorderStyle = LineStyle.Rounded;
+        _chatFrame.BorderStyle = LineStyle.Rounded;
+        _inputFrame.BorderStyle = LineStyle.Rounded;
+        _usersFrame.BorderStyle = LineStyle.Rounded;
+
         // Apply our custom color schemes to all views
         ApplyColorSchemes();
 
@@ -1016,6 +1022,7 @@ public sealed partial class MainWindow : Runnable
     public void UpdateStatusBar(string status)
     {
         _connectionStatus = status;
+        UpdateSpinner();
         _statusLabel.SetNeedsDraw();
     }
 
@@ -1023,6 +1030,38 @@ public sealed partial class MainWindow : Runnable
     private static readonly Attribute StatusDisconnectedAttr = new(new Color(220, 50, 50), Color.None);
     private static readonly Attribute StatusTransitionalAttr = new(new Color(220, 180, 0), Color.None);
     private static readonly Attribute StatusBrandAttr = new(new Color(218, 165, 32), Color.None);
+    private static readonly Attribute StatusActivityAttr = new(new Color(80, 200, 220), Color.None);
+    private static readonly Attribute StatusMentionAttr = new(new Color(230, 140, 60), Color.None);
+
+    // Braille spinner shown while the connection is in a transitional state
+    private static readonly string[] SpinnerFrames = ["⠋", "⠙", "⠹", "⠸", "⠼", "⠴", "⠦", "⠧", "⠇", "⠏"];
+    private object? _spinnerToken;
+    private int _spinnerFrame;
+
+    private bool IsTransitionalStatus => _connectionStatus is not ("Connected" or "Disconnected");
+
+    /// <summary>
+    /// Starts the spinner timer when entering a transitional connection state
+    /// (Connecting, Reconnecting, …); the timer stops itself once the state settles.
+    /// </summary>
+    private void UpdateSpinner()
+    {
+        if (!IsTransitionalStatus || _spinnerToken is not null)
+            return;
+
+        _spinnerToken = _app.AddTimeout(TimeSpan.FromMilliseconds(120), () =>
+        {
+            if (!IsTransitionalStatus)
+            {
+                _spinnerToken = null;
+                return false;
+            }
+
+            _spinnerFrame = (_spinnerFrame + 1) % SpinnerFrames.Length;
+            _statusLabel.SetNeedsDraw();
+            return true;
+        });
+    }
 
     private void OnStatusBarDrawContent(object? sender, DrawEventArgs e)
     {
@@ -1054,13 +1093,15 @@ public sealed partial class MainWindow : Runnable
         Write(" EchoHub", Resolve(StatusBrandAttr));
         Write($" \u2502 v{AppVersion} \u2502 ", normalAttr);
 
-        // Connection state with color
+        // Connection state with color; transitional states get an animated spinner
         var statusAttr = _connectionStatus switch
         {
             "Connected" => StatusConnectedAttr,
             "Disconnected" => StatusDisconnectedAttr,
             _ => StatusTransitionalAttr // Connecting, Reconnecting, Authenticating, etc.
         };
+        if (IsTransitionalStatus)
+            Write($"{SpinnerFrames[_spinnerFrame]} ", statusAttr);
         Write(_connectionStatus, Resolve(statusAttr));
 
         // User
@@ -1079,6 +1120,28 @@ public sealed partial class MainWindow : Runnable
             Write($" \u2502 #{currentChannel} - {typeSuffix}", normalAttr);
         }
 
+        // Activity segment (irssi-style): channels with unread messages,
+        // mention-channels highlighted in orange
+        var activity = _messageManager.GetUnreadCounts()
+            .Where(kv => kv.Value > 0)
+            .Select(kv => kv.Key)
+            .OrderBy(n => n, StringComparer.OrdinalIgnoreCase)
+            .ToList();
+        if (activity.Count > 0)
+        {
+            const int maxShown = 4;
+            Write(" \u2502 Act: ", normalAttr);
+            var mentions = _messageManager.MentionChannels;
+            for (int i = 0; i < activity.Count && i < maxShown; i++)
+            {
+                if (i > 0)
+                    Write(",", normalAttr);
+                Write($"#{activity[i]}", mentions.Contains(activity[i]) ? StatusMentionAttr : StatusActivityAttr);
+            }
+            if (activity.Count > maxShown)
+                Write($" +{activity.Count - maxShown}", normalAttr);
+        }
+
         // Fill remaining space
         _statusLabel.SetAttribute(normalAttr);
         while (col < width)
@@ -1180,9 +1243,6 @@ public sealed partial class MainWindow : Runnable
     }
 
     private void RefreshMessages()
-    {
-        var messages = _messageManager.GetMessages(_messageManager.CurrentChannel);
-        if (messages is not null)
     {
         var width = _messageList.Viewport.Width;
 
@@ -1193,13 +1253,21 @@ public sealed partial class MainWindow : Runnable
         else
             width = _lastChatWidth;
 
+        var messages = _messageManager.GetMessages(_messageManager.CurrentChannel);
+        if (messages is not null)
+        {
             var source = new ChatListSource();
 
             if (width > 0)
             {
                 foreach (var line in messages)
+                {
+                    if (line.RuleLabel is not null)
+                        source.Add(ExpandRule(line, width));
+                    else
                         source.AddRange(line.Wrap(width, line.ContinuationIndent));
                 }
+            }
             else
             {
                 source.AddRange(messages);
@@ -1211,16 +1279,36 @@ public sealed partial class MainWindow : Runnable
         }
         else
         {
-            _messageList.Source = new ChatListSource();
+            // No channel selected — greet with the MOTD-style splash
+            var source = new ChatListSource();
+            if (width > 0)
+                source.AddRange(WelcomeBanner.Build(width, AppVersion));
+            _messageList.Source = source;
         }
     }
 
+    /// <summary>
+    /// Regenerates a separator rule (date change / unread marker) to span the
+    /// current viewport width: "── label ────────…".
+    /// </summary>
+    private static ChatLine ExpandRule(ChatLine line, int width)
+    {
+        var attr = line.RuleAttr ?? ChatColors.DateRuleAttr;
+        var label = line.RuleLabel!;
+        var tailLen = Math.Max(width - 4 - label.GetColumns() - 1, 2);
+        return new ChatLine([new ChatSegment($"── {label} {new string('─', tailLen)}", attr)])
+        {
+            IsUnreadMarker = line.IsUnreadMarker,
+        };
+    }
+
     /// <summary>
     /// Refresh the channel list view, showing unread counts next to channel names.
     /// </summary>
     private void RefreshChannelList()
     {
-        _channelListSource.Update(_channelNames, _messageManager.GetUnreadCounts(), _messageManager.CurrentChannel, _channelProtected);
+        _channelListSource.Update(_channelNames, _messageManager.GetUnreadCounts(), _messageManager.CurrentChannel,
+            _channelProtected, _messageManager.MentionChannels);
         _channelList.Source = _channelListSource;
 
         // Restore selection to current channel
@@ -1296,8 +1384,11 @@ public sealed partial class MainWindow : Runnable
             var text = roleTag.Length > 0
                 ? $"{statusIcon} {roleTag} {name}"
                 : $"{statusIcon} {name}";
-            var nameColor = HexColorHelper.ParseHexColor(u.NicknameColor);
+            // Fall back to the deterministic per-nick palette so user-list colors
-            return (text, nameColor, u.Username);
+            // match the same user's messages in chat.
+            var nameColor = HexColorHelper.ParseHexColor(u.NicknameColor)
+                ?? NickColorHelper.GetAttribute(u.Username);
+            return (text, (Attribute?)nameColor, u.Username);
         }).ToList();
 
         _usersListSource.Update(displayItems);

src/EchoHub.Tests/NickColorHelperTests.cs

@@ -0,0 +1,55 @@
+using EchoHub.Client.UI.Helpers;
+using Xunit;
+
+namespace EchoHub.Tests;
+
+/// <summary>
+/// Tests for the deterministic nick→palette-index hash.
+/// Note: GetAttribute (Terminal.Gui Attribute) is excluded — Terminal.Gui's module
+/// initializer requires a display driver unavailable in CI.
+/// </summary>
+public class NickColorHelperTests
+{
+    [Fact]
+    public void GetPaletteIndex_SameNick_IsStable()
+    {
+        var first = NickColorHelper.GetPaletteIndex("alice", 12);
+        var second = NickColorHelper.GetPaletteIndex("alice", 12);
+        Assert.Equal(first, second);
+    }
+
+    [Fact]
+    public void GetPaletteIndex_IsCaseInsensitive()
+    {
+        Assert.Equal(
+            NickColorHelper.GetPaletteIndex("Alice", 12),
+            NickColorHelper.GetPaletteIndex("aLICE", 12));
+    }
+
+    [Theory]
+    [InlineData("alice")]
+    [InlineData("bob")]
+    [InlineData("charlie_long_nickname")]
+    [InlineData("")]
+    [InlineData("émile")]
+    public void GetPaletteIndex_AlwaysWithinRange(string nick)
+    {
+        var index = NickColorHelper.GetPaletteIndex(nick, 12);
+        Assert.InRange(index, 0, 11);
+    }
+
+    [Fact]
+    public void GetPaletteIndex_DistributesAcrossPalette()
+    {
+        // Not a strict uniformity test — just that the hash isn't degenerate
+        var nicks = new[] { "alice", "bob", "carol", "dave", "erin", "frank", "grace", "heidi" };
+        var distinct = nicks.Select(n => NickColorHelper.GetPaletteIndex(n, 12)).Distinct().Count();
+        Assert.True(distinct >= 3, $"Expected at least 3 distinct palette slots, got {distinct}");
+    }
+
+    [Fact]
+    public void GetPaletteIndex_NonPositivePaletteSize_ReturnsZero()
+    {
+        Assert.Equal(0, NickColorHelper.GetPaletteIndex("alice", 0));
+    }
+}