feat: add /ping and /status diagnostics commands

Author: HandyS11

src/RustPlusBot.Features.Commands/Modules/DiagnosticsModule.cs

@@ -0,0 +1,74 @@
+using System.Diagnostics;
+using System.Globalization;
+using Discord;
+using Discord.Interactions;
+using Microsoft.Extensions.DependencyInjection;
+using RustPlusBot.Features.Commands.Formatting;
+using RustPlusBot.Features.Commands.Hosting;
+using RustPlusBot.Persistence.Connections;
+using RustPlusBot.Persistence.Servers;
+
+namespace RustPlusBot.Features.Commands.Modules;
+
+/// <summary>Read-only diagnostics: /ping and /status.</summary>
+/// <param name="scopeFactory">Creates a short-lived DI scope per interaction.</param>
+public sealed class DiagnosticsModule(IServiceScopeFactory scopeFactory)
+    : InteractionModuleBase<SocketInteractionContext>
+{
+    /// <summary>Reports Discord gateway latency and the REST ack round-trip.</summary>
+    [SlashCommand("ping", "Show the bot's Discord latency")]
+    public async Task PingAsync()
+    {
+        var stopwatch = Stopwatch.StartNew();
+        await DeferAsync(ephemeral: true).ConfigureAwait(false);
+        stopwatch.Stop();
+
+        var text = string.Create(CultureInfo.InvariantCulture,
+            $"Pong! Gateway: {Context.Client.Latency} ms · Response: {stopwatch.ElapsedMilliseconds} ms");
+        await FollowupAsync(text, ephemeral: true).ConfigureAwait(false);
+    }
+
+    /// <summary>Shows uptime, latency, per-server connection status, and counts.</summary>
+    [SlashCommand("status", "Show bot health and connection status")]
+    public async Task StatusAsync()
+    {
+        if (Context.Guild is null)
+        {
+            await RespondAsync("This command must be used in a server.", ephemeral: true).ConfigureAwait(false);
+            return;
+        }
+
+        await DeferAsync(ephemeral: true).ConfigureAwait(false);
+        var scope = scopeFactory.CreateAsyncScope();
+        await using (scope.ConfigureAwait(false))
+        {
+            var uptime = scope.ServiceProvider.GetRequiredService<BotUptime>();
+            var servers = scope.ServiceProvider.GetRequiredService<IServerService>();
+            var connections = scope.ServiceProvider.GetRequiredService<IConnectionStore>();
+
+            var known = await servers.ListAsync(Context.Guild.Id).ConfigureAwait(false);
+
+            var embed = new EmbedBuilder()
+                .WithTitle("Bot status")
+                .AddField("Uptime", DurationFormat.Compact(uptime.Elapsed), inline: true)
+                .AddField("Gateway latency",
+                    string.Create(CultureInfo.InvariantCulture, $"{Context.Client.Latency} ms"), inline: true)
+                .AddField("Guilds",
+                    Context.Client.Guilds.Count.ToString(CultureInfo.InvariantCulture), inline: true)
+                .AddField("Servers (this guild)",
+                    known.Count.ToString(CultureInfo.InvariantCulture), inline: true);
+
+            foreach (var server in known)
+            {
+                var state = await connections.GetStateAsync(Context.Guild.Id, server.Id).ConfigureAwait(false);
+                var line = state is null
+                    ? "unknown"
+                    : string.Create(CultureInfo.InvariantCulture,
+                        $"{state.Status} · {state.PlayerCount?.ToString(CultureInfo.InvariantCulture) ?? "?"} players");
+                embed.AddField(server.Name, line);
+            }
+
+            await FollowupAsync(ephemeral: true, embed: embed.Build()).ConfigureAwait(false);
+        }
+    }
+}