Added release notifications to data/bot.yml Notifications are sent to all owners in dms

src/NadekoBot/Modules/Administration/Self/CheckForUpdatesService.cs

@@ -0,0 +1,153 @@
+using System.Net.Http.Json;
+using System.Text;
+using NadekoBot.Common.ModuleBehaviors;
+
+namespace NadekoBot.Modules.Administration.Self;
+
+public sealed class CheckForUpdatesService : INService, IReadyExecutor
+{
+    private readonly BotConfigService _bcs;
+    private readonly IBotCredsProvider _bcp;
+    private readonly IHttpClientFactory _httpFactory;
+    private readonly DiscordSocketClient _client;
+    private readonly IEmbedBuilderService _ebs;
+
+    public CheckForUpdatesService(BotConfigService bcs, IBotCredsProvider bcp, IHttpClientFactory httpFactory,
+        DiscordSocketClient client, IEmbedBuilderService ebs)
+    {
+        _bcs = bcs;
+        _bcp = bcp;
+        _httpFactory = httpFactory;
+        _client = client;
+        _ebs = ebs;
+    }
+    
+    public async Task OnReadyAsync()
+    {
+        if (_client.ShardId != 0)
+            return;
+        
+        using var timer = new PeriodicTimer(TimeSpan.FromSeconds(15));
+        while (await timer.WaitForNextTickAsync())
+        {
+            var conf = _bcs.Data;
+
+            if (!conf.CheckForUpdates)
+                continue;
+            
+            try
+            {
+                const string URL = "https://cdn.nadeko.bot/cmds/versions.json";
+                using var http = _httpFactory.CreateClient();
+                var versions = await http.GetFromJsonAsync<string[]>(URL);
+
+                if (versions is null)
+                    continue;
+                
+                var latest = versions[0];
+                var latestVersion = Version.Parse(latest);
+                var lastKnownVersion = GetLastKnownVersion();
+
+                if (lastKnownVersion is null)
+                {
+                    UpdateLastKnownVersion(latestVersion);
+                    continue;
+                }
+                
+                if (latestVersion > lastKnownVersion)
+                {
+                    UpdateLastKnownVersion(latestVersion);
+                    
+                    // pull changelog
+                    var changelog = await http.GetStringAsync("https://gitlab.com/Kwoth/nadekobot/-/raw/v4/CHANGELOG.md");
+
+                    var thisVersionChangelog = GetVersionChangelog(latestVersion, changelog);
+
+                    if (string.IsNullOrWhiteSpace(thisVersionChangelog))
+                    {
+                        Log.Warning("New version {BotVersion} was found but changelog is unavailable",
+                            thisVersionChangelog);
+                        continue;
+                    }
+
+                    var creds = _bcp.GetCreds();
+                    await creds.OwnerIds
+                        .Select(async x =>
+                        {
+                            var user = await _client.GetUserAsync(x);
+                            if (user is null)
+                                return;
+
+                            var eb = _ebs.Create()
+                                .WithOkColor()
+                                .WithAuthor($"NadekoBot v{latestVersion} Released!")
+                                .WithTitle("Changelog")
+                                .WithUrl("https://gitlab.com/Kwoth/nadekobot/-/blob/v4/CHANGELOG.md")
+                                .WithDescription(thisVersionChangelog.TrimTo(4096))
+                                .WithFooter("You may disable these messages by typing '.conf bot checkforupdates false'");
+
+                            await user.EmbedAsync(eb);
+                        }).WhenAll();
+                }
+            }
+            catch (Exception ex)
+            {
+                Log.Error(ex, "Error while checking for new bot release: {ErrorMessage}", ex.Message);
+            }
+        }
+    }
+
+    private string? GetVersionChangelog(Version latestVersion, string changelog)
+    {
+        var clSpan = changelog.AsSpan();
+
+        var sb = new StringBuilder();
+        var started = false;
+        foreach (var line in clSpan.EnumerateLines())
+        {
+            // if we're at the current version, keep reading lines and adding to the output
+            if (started)
+            {
+                // if we got to previous version, end
+                if (line.StartsWith("## ["))
+                    break;
+                
+                // if we're reading a new segment, reformat it to print it better to discord
+                if (line.StartsWith("### "))
+                {
+                    sb.AppendLine(Format.Bold(line.ToString()));
+                }
+                else
+                {
+                    sb.AppendLine(line.ToString());
+                }
+
+                continue;
+            }
+
+            if (line.StartsWith($"## [{latestVersion.ToString()}]"))
+            {
+                started = true;
+                continue;
+            }
+        }
+
+        return sb.ToString();
+    }
+
+    private const string LAST_KNOWN_VERSION_PATH = "data/last_known_version.txt";
+    private Version? GetLastKnownVersion()
+    {
+        if (!File.Exists(LAST_KNOWN_VERSION_PATH))
+            return null;
+        
+        return Version.TryParse(File.ReadAllText(LAST_KNOWN_VERSION_PATH), out var ver)
+            ? ver
+            : null;
+    }
+
+    private void UpdateLastKnownVersion(Version version)
+    {
+        File.WriteAllText("data/last_known_version.txt", version.ToString());
+    }
+}