feat: notification digests via SMTP

Adds a periodic inbox-summary email per opted-in user. SMTP is configured via appsettings (Smtp section); the digest is built from existing analytics (health score, top senders, recommendations) and sent by a new hourly DigestWorker, mirroring the GmailSyncWorker pattern. Frequency and send hour are configurable (Digest section). Backend: IEmailSender (SmtpEmailSender, MailKit), IDigestService, DigestWorker, new User.DigestEnabled/LastDigestSentUtc fields + migration, SettingsController for the per-user toggle and a send-now test endpoint, all scoped to the authenticated UserId. Frontend: SettingsApi + a bell/no-bell toggle button in the topbar. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
2026-06-30 22:11:39 +02:00
parent 9bd3799fbc
commit 0163165beb
17 changed files with 1113 additions and 0 deletions
@@ -0,0 +1,65 @@
+using System.Text;
+using InboxIntel.Application.Abstractions;
+using InboxIntel.Infrastructure.Persistence;
+using Microsoft.EntityFrameworkCore;
+
+namespace InboxIntel.Infrastructure.Notifications;
+
+/// <summary>Builds an HTML inbox-summary email and sends it via <see cref="IEmailSender"/>.</summary>
+public class DigestService : IDigestService
+{
+    private readonly AppDbContext _db;
+    private readonly IAnalyticsService _analytics;
+    private readonly IEmailSender _emailSender;
+
+    public DigestService(AppDbContext db, IAnalyticsService analytics, IEmailSender emailSender)
+    {
+        _db = db;
+        _analytics = analytics;
+        _emailSender = emailSender;
+    }
+
+    public async Task SendDigestAsync(Guid userId, CancellationToken ct = default)
+    {
+        var user = await _db.Users.FirstOrDefaultAsync(u => u.Id == userId, ct);
+        if (user is null || string.IsNullOrWhiteSpace(user.Email)) return;
+
+        var dashboard = await _analytics.GetDashboardAsync(userId, ct);
+        var html = BuildHtml(dashboard);
+
+        await _emailSender.SendAsync(user.Email, "Your InboxIntel digest", html, ct);
+
+        user.LastDigestSentUtc = DateTimeOffset.UtcNow;
+        await _db.SaveChangesAsync(ct);
+    }
+
+    private static string BuildHtml(Application.DTOs.DashboardSummaryDto d)
+    {
+        var sb = new StringBuilder();
+        sb.Append("<div style=\"font-family:sans-serif;max-width:480px\">");
+        sb.Append("<h2>Your inbox this week</h2>");
+        sb.Append($"<p><strong>{d.Health.Score}/100</strong> inbox health (grade {d.Health.Grade})</p>");
+        sb.Append($"<p>{d.UnreadEmails:N0} unread of {d.TotalEmails:N0} total emails</p>");
+        if (d.Health.SafeToUnsubscribeCount > 0)
+            sb.Append($"<p>{d.Health.SafeToUnsubscribeCount} senders are safe to unsubscribe from.</p>");
+
+        if (d.TopSenders.Count > 0)
+        {
+            sb.Append("<h3>Top senders</h3><ul>");
+            foreach (var s in d.TopSenders.Take(5))
+                sb.Append($"<li>{System.Net.WebUtility.HtmlEncode(s.DisplayName ?? s.Address)} — {s.EmailCount:N0} emails</li>");
+            sb.Append("</ul>");
+        }
+
+        if (d.Health.Recommendations.Count > 0)
+        {
+            sb.Append("<h3>Recommendations</h3><ul>");
+            foreach (var r in d.Health.Recommendations)
+                sb.Append($"<li>{System.Net.WebUtility.HtmlEncode(r)}</li>");
+            sb.Append("</ul>");
+        }
+
+        sb.Append("</div>");
+        return sb.ToString();
+    }
+}