support PWA notification.

API/ROLAC.API/Controllers/NotificationsController.cs

@@ -1,6 +1,7 @@
 using Microsoft.AspNetCore.Authorization;
 using Microsoft.AspNetCore.Mvc;
 using Microsoft.EntityFrameworkCore;
+using ROLAC.API.Authorization;
 using ROLAC.API.Data;
 using ROLAC.API.DTOs.Notifications;
 using ROLAC.API.Services.Logging;
@@ -20,15 +21,17 @@ public sealed class NotificationsController : ControllerBase
 {
     private readonly IEmailService _email;
     private readonly ILineNotificationService _line;
+    private readonly IWebPushService _webPush;
     private readonly AppDbContext _db;
     private readonly CurrentUserAccessor _currentUser;
 
     public NotificationsController(
-        IEmailService email, ILineNotificationService line,
+        IEmailService email, ILineNotificationService line, IWebPushService webPush,
         AppDbContext db, CurrentUserAccessor currentUser)
     {
         _email = email;
         _line = line;
+        _webPush = webPush;
         _db = db;
         _currentUser = currentUser;
     }
@@ -92,4 +95,14 @@ public sealed class NotificationsController : ControllerBase
             HtmlBody: request.HtmlBody,
             Attachments: null,
             SentByUserId: _currentUser.UserIdOrSystem), ct));
+
+    // Manual one-to-(few) Web Push send. Guarded by Settings:Write (sending is an admin capability);
+    // the Member Management "send push" test action calls this for a single member.
+    [HttpPost("send-webpush")]
+    [HasPermission(Modules.Settings, PermissionActions.Write)]
+    public async Task<IActionResult> SendWebPush([FromBody] SendWebPushRequest request, CancellationToken ct)
+        => Ok(await _webPush.SendToMembersAsync(
+            request.MemberIds ?? [],
+            new WebPushPayload(request.Title, request.Body, request.Url),
+            _currentUser.UserIdOrSystem, ct));
 }

API/ROLAC.API/Controllers/PushSubscriptionsController.cs

@@ -0,0 +1,110 @@
+using Microsoft.AspNetCore.Authorization;
+using Microsoft.AspNetCore.Mvc;
+using Microsoft.EntityFrameworkCore;
+using ROLAC.API.Data;
+using ROLAC.API.DTOs.Push;
+using ROLAC.API.Entities.Notifications;
+using ROLAC.API.Services.Logging;
+using ROLAC.API.Services.Notifications;
+
+namespace ROLAC.API.Controllers;
+
+/// <summary>
+/// Self-service Web Push subscription management for the logged-in member: hand out the VAPID public
+/// key, store the browser's subscription, and remove it on opt-out. Subscriptions are keyed to the
+/// caller's linked Member, so an admin-only account (no MemberId) cannot subscribe.
+/// </summary>
+[ApiController]
+[Route("api/push")]
+[Authorize]
+public sealed class PushSubscriptionsController : ControllerBase
+{
+    private readonly AppDbContext _db;
+    private readonly INotificationSettingsService _settings;
+    private readonly IWebPushService _webPush;
+    private readonly CurrentUserAccessor _currentUser;
+
+    public PushSubscriptionsController(
+        AppDbContext db, INotificationSettingsService settings,
+        IWebPushService webPush, CurrentUserAccessor currentUser)
+    {
+        _db = db;
+        _settings = settings;
+        _webPush = webPush;
+        _currentUser = currentUser;
+    }
+
+    [HttpGet("vapid-public-key")]
+    public IActionResult VapidPublicKey()
+        => Ok(new { publicKey = _settings.GetWebPush().PublicKey });
+
+    [HttpPost("subscriptions")]
+    public async Task<IActionResult> Subscribe([FromBody] PushSubscriptionRequest request, CancellationToken ct)
+    {
+        var memberId = await CurrentMemberIdAsync(ct);
+        if (memberId is null)
+            return Conflict(new { message = "This account is not linked to a member, so it cannot receive push notifications." });
+
+        var existing = await _db.WebPushSubscriptions
+            .FirstOrDefaultAsync(subscription => subscription.Endpoint == request.Endpoint, ct);
+
+        if (existing is null)
+        {
+            _db.WebPushSubscriptions.Add(new WebPushSubscription
+            {
+                MemberId  = memberId.Value,
+                Endpoint  = request.Endpoint,
+                P256dh    = request.Keys.P256dh,
+                Auth      = request.Keys.Auth,
+                UserAgent = request.UserAgent,
+                CreatedAt = DateTime.UtcNow,
+            });
+        }
+        else
+        {
+            // Same endpoint re-subscribed (e.g. keys rotated, or now a different member on this browser).
+            existing.MemberId  = memberId.Value;
+            existing.P256dh    = request.Keys.P256dh;
+            existing.Auth      = request.Keys.Auth;
+            existing.UserAgent = request.UserAgent;
+        }
+
+        await _db.SaveChangesAsync(ct);
+        return NoContent();
+    }
+
+    [HttpDelete("subscriptions")]
+    public async Task<IActionResult> Unsubscribe([FromBody] PushUnsubscribeRequest request, CancellationToken ct)
+    {
+        var subscription = await _db.WebPushSubscriptions
+            .FirstOrDefaultAsync(s => s.Endpoint == request.Endpoint, ct);
+        if (subscription is not null)
+        {
+            _db.WebPushSubscriptions.Remove(subscription);
+            await _db.SaveChangesAsync(ct);
+        }
+        return NoContent();
+    }
+
+    // Sends a canned push to the caller's own devices so they can confirm notifications work.
+    [HttpPost("test")]
+    public async Task<IActionResult> SendTestToSelf(CancellationToken ct)
+    {
+        var memberId = await CurrentMemberIdAsync(ct);
+        if (memberId is null)
+            return Conflict(new { message = "This account is not linked to a member, so it cannot receive push notifications." });
+
+        var result = await _webPush.SendToMembersAsync(
+            new[] { memberId.Value },
+            new WebPushPayload("River of Life", "通知測試成功！This is a test notification.", "/user-portal/account"),
+            _currentUser.UserIdOrSystem, ct);
+        return Ok(result);
+    }
+
+    private async Task<int?> CurrentMemberIdAsync(CancellationToken ct)
+    {
+        var userId = _currentUser.UserId;
+        if (string.IsNullOrEmpty(userId)) return null;
+        return await _db.Users.Where(user => user.Id == userId).Select(user => user.MemberId).FirstOrDefaultAsync(ct);
+    }
+}

API/ROLAC.API/DTOs/Notifications/NotificationRequests.cs

@@ -5,3 +5,6 @@ public sealed record UpdateGroupRequest(string? Name, bool IsActive);
 public sealed record SendLineRequest(string Body, int[]? MemberIds, int[]? GroupIds);
 
 public sealed record SendEmailRequest(string Subject, string HtmlBody, int[]? MemberIds, string[]? Addresses);
+
+/// <summary>Admin manual Web Push send to one or more members (used by the Member Management test action).</summary>
+public sealed record SendWebPushRequest(int[]? MemberIds, string Title, string Body, string? Url);

API/ROLAC.API/DTOs/Push/PushSubscriptionDtos.cs

@@ -0,0 +1,9 @@
+namespace ROLAC.API.DTOs.Push;
+
+/// <summary>The PushSubscription a browser produces, posted when a member enables notifications.</summary>
+public sealed record PushSubscriptionRequest(string Endpoint, PushSubscriptionKeys Keys, string? UserAgent);
+
+public sealed record PushSubscriptionKeys(string P256dh, string Auth);
+
+/// <summary>Identifies the subscription to remove when a member disables notifications.</summary>
+public sealed record PushUnsubscribeRequest(string Endpoint);

API/ROLAC.API/Data/AppDbContext.cs

@@ -38,6 +38,7 @@ public class AppDbContext : IdentityDbContext<AppUser, AppRole, string>
     public DbSet<LineBindingCode>      LineBindingCodes      => Set<LineBindingCode>();
     public DbSet<MessagingGroup>       MessagingGroups       => Set<MessagingGroup>();
     public DbSet<NotificationLog>      NotificationLogs      => Set<NotificationLog>();
+    public DbSet<WebPushSubscription>  WebPushSubscriptions  => Set<WebPushSubscription>();
 
     public DbSet<SiteSetting>          SiteSettings          => Set<SiteSetting>();
     public DbSet<NotificationSetting>  NotificationSettings  => Set<NotificationSetting>();
@@ -560,6 +561,18 @@ public class AppDbContext : IdentityDbContext<AppUser, AppRole, string>
                   .HasForeignKey(e => e.MessagingGroupId).OnDelete(DeleteBehavior.SetNull);
         });
 
+        builder.Entity<WebPushSubscription>(entity =>
+        {
+            entity.Property(e => e.Endpoint).HasMaxLength(2000).IsRequired();
+            entity.Property(e => e.P256dh).HasMaxLength(200).IsRequired();
+            entity.Property(e => e.Auth).HasMaxLength(100).IsRequired();
+            entity.Property(e => e.UserAgent).HasMaxLength(400);
+            entity.HasIndex(e => e.Endpoint).IsUnique();
+            entity.HasIndex(e => e.MemberId);
+            entity.HasOne(e => e.Member).WithMany()
+                  .HasForeignKey(e => e.MemberId).OnDelete(DeleteBehavior.Cascade);
+        });
+
         // ── SystemLog / AuditLog (append-only) ───────────────────────────────
         // Mapped here for SCHEMA only — there are deliberately no DbSets on this
         // context, so business code can't write logs through the audited context.

API/ROLAC.API/Data/DbSeeder.cs

@@ -474,6 +474,20 @@ public static class DbSeeder
             });
             await db.SaveChangesAsync();
         }
+
+        // Generate the VAPID key pair once so Web Push works out of the box. Persisted on the
+        // singleton row; the public key is handed to browsers, the private key signs each push.
+        var row = await db.NotificationSettings.OrderBy(s => s.Id).FirstAsync();
+        if (string.IsNullOrWhiteSpace(row.VapidPublicKey))
+        {
+            var keys = WebPush.VapidHelper.GenerateVapidKeys();
+            row.VapidPublicKey  = keys.PublicKey;
+            row.VapidPrivateKey = keys.PrivateKey;
+            if (string.IsNullOrWhiteSpace(row.VapidSubject))
+                row.VapidSubject = "mailto:admin@rolac.local";
+            row.EnableWebPush = true;
+            await db.SaveChangesAsync();
+        }
     }
 
     /// <summary>

API/ROLAC.API/Entities/NotificationSetting.cs

@@ -29,4 +29,12 @@ public class NotificationSetting : AuditableEntity, IAuditable
     public bool   EnableLine             { get; set; }
     public string LineChannelAccessToken { get; set; } = "";
     public string LineChannelSecret      { get; set; } = "";
+
+    // ── Web Push (PWA browser notifications) ───────────────────────────────────
+    // VAPID keys identify this server to the push services. The pair is generated once on first
+    // startup if empty; the public key is safe to hand to the browser, the private key is a secret.
+    public bool   EnableWebPush   { get; set; }
+    public string VapidPublicKey  { get; set; } = "";
+    public string VapidPrivateKey { get; set; } = "";
+    public string VapidSubject    { get; set; } = "";   // "mailto:..." or the site URL
 }

API/ROLAC.API/Entities/Notifications/WebPushSubscription.cs

@@ -0,0 +1,33 @@
+using ROLAC.API.Entities;
+
+namespace ROLAC.API.Entities.Notifications;
+
+/// <summary>
+/// A browser/device Web Push subscription owned by a member. Unlike <see cref="MemberChannelBinding"/>
+/// (one external id per channel), web push needs the endpoint URL plus two keys, and a member can
+/// have several — one per device/browser they enable notifications on. Targeting a member resolves
+/// all of their subscriptions.
+/// </summary>
+public class WebPushSubscription
+{
+    public int      Id         { get; set; }
+    public int      MemberId   { get; set; }
+    public Member?  Member     { get; set; }
+
+    /// <summary>The push service endpoint URL (unique per subscription).</summary>
+    public string   Endpoint   { get; set; } = null!;
+
+    /// <summary>The subscription's P-256 ECDH public key (base64url).</summary>
+    public string   P256dh     { get; set; } = null!;
+
+    /// <summary>The subscription's auth secret (base64url).</summary>
+    public string   Auth       { get; set; } = null!;
+
+    /// <summary>The originating user agent, kept for display/debugging.</summary>
+    public string?  UserAgent  { get; set; }
+
+    public DateTime CreatedAt  { get; set; }
+
+    /// <summary>Last time a push to this subscription succeeded.</summary>
+    public DateTime? LastUsedAt { get; set; }
+}

API/ROLAC.API/Migrations/AppDbContextModelSnapshot.cs

@@ -1704,6 +1704,9 @@ namespace ROLAC.API.Migrations
                     b.Property<bool>("EnableLine")
                         .HasColumnType("boolean");
 
+                    b.Property<bool>("EnableWebPush")
+                        .HasColumnType("boolean");
+
                     b.Property<string>("FromAddress")
                         .IsRequired()
                         .HasMaxLength(200)
@@ -1753,6 +1756,18 @@ namespace ROLAC.API.Migrations
                         .HasMaxLength(450)
                         .HasColumnType("character varying(450)");
 
+                    b.Property<string>("VapidPrivateKey")
+                        .IsRequired()
+                        .HasColumnType("text");
+
+                    b.Property<string>("VapidPublicKey")
+                        .IsRequired()
+                        .HasColumnType("text");
+
+                    b.Property<string>("VapidSubject")
+                        .IsRequired()
+                        .HasColumnType("text");
+
                     b.HasKey("Id");
 
                     b.ToTable("NotificationSettings");
@@ -1926,6 +1941,52 @@ namespace ROLAC.API.Migrations
                     b.ToTable("NotificationLogs");
                 });
 
+            modelBuilder.Entity("ROLAC.API.Entities.Notifications.WebPushSubscription", b =>
+                {
+                    b.Property<int>("Id")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("integer");
+
+                    NpgsqlPropertyBuilderExtensions.UseIdentityByDefaultColumn(b.Property<int>("Id"));
+
+                    b.Property<string>("Auth")
+                        .IsRequired()
+                        .HasMaxLength(100)
+                        .HasColumnType("character varying(100)");
+
+                    b.Property<DateTime>("CreatedAt")
+                        .HasColumnType("timestamp with time zone");
+
+                    b.Property<string>("Endpoint")
+                        .IsRequired()
+                        .HasMaxLength(2000)
+                        .HasColumnType("character varying(2000)");
+
+                    b.Property<DateTime?>("LastUsedAt")
+                        .HasColumnType("timestamp with time zone");
+
+                    b.Property<int>("MemberId")
+                        .HasColumnType("integer");
+
+                    b.Property<string>("P256dh")
+                        .IsRequired()
+                        .HasMaxLength(200)
+                        .HasColumnType("character varying(200)");
+
+                    b.Property<string>("UserAgent")
+                        .HasMaxLength(400)
+                        .HasColumnType("character varying(400)");
+
+                    b.HasKey("Id");
+
+                    b.HasIndex("Endpoint")
+                        .IsUnique();
+
+                    b.HasIndex("MemberId");
+
+                    b.ToTable("WebPushSubscriptions");
+                });
+
             modelBuilder.Entity("ROLAC.API.Entities.OfferingSession", b =>
                 {
                     b.Property<int>("Id")
@@ -2599,6 +2660,17 @@ namespace ROLAC.API.Migrations
                     b.Navigation("MessagingGroup");
                 });
 
+            modelBuilder.Entity("ROLAC.API.Entities.Notifications.WebPushSubscription", b =>
+                {
+                    b.HasOne("ROLAC.API.Entities.Member", "Member")
+                        .WithMany()
+                        .HasForeignKey("MemberId")
+                        .OnDelete(DeleteBehavior.Cascade)
+                        .IsRequired();
+
+                    b.Navigation("Member");
+                });
+
             modelBuilder.Entity("ROLAC.API.Entities.Payee1099", b =>
                 {
                     b.HasOne("ROLAC.API.Entities.Member", "Member")

API/ROLAC.API/Program.cs

@@ -188,6 +188,10 @@ builder.Services.AddScoped<ROLAC.API.Services.Notifications.ILineNotificationSer
                            ROLAC.API.Services.Notifications.LineNotificationService>();
 builder.Services.AddHttpClient<ROLAC.API.Services.Notifications.IMessageChannel,
                                ROLAC.API.Services.Notifications.LineMessageChannel>();
+builder.Services.AddScoped<ROLAC.API.Services.Notifications.IWebPushSender,
+                           ROLAC.API.Services.Notifications.WebPushSender>();
+builder.Services.AddScoped<ROLAC.API.Services.Notifications.IWebPushService,
+                           ROLAC.API.Services.Notifications.WebPushService>();
 
 // ── AI assist (expense translation + category suggestion) ──────────────────
 // Backend proxy so the API key stays server-side. Provider + model + key come from the

API/ROLAC.API/ROLAC.API.csproj

@@ -26,6 +26,7 @@
 
 		<PackageReference Include="Npgsql.EntityFrameworkCore.PostgreSQL" Version="8.0.11" />
 		<PackageReference Include="Swashbuckle.AspNetCore" Version="6.6.2" />
+		<PackageReference Include="WebPush" Version="1.0.12" />
 	</ItemGroup>
 
 </Project>

API/ROLAC.API/Services/Notifications/IWebPushSender.cs

@@ -0,0 +1,19 @@
+namespace ROLAC.API.Services.Notifications;
+
+/// <summary>The three fields a browser hands over when it creates a push subscription.</summary>
+public sealed record WebPushTarget(string Endpoint, string P256dh, string Auth);
+
+/// <summary>
+/// Outcome of pushing to one subscription. <see cref="IsExpired"/> is true when the push service
+/// reported the subscription is gone (HTTP 404/410) so the caller can prune it.
+/// </summary>
+public sealed record WebPushSendResult(bool Success, bool IsExpired, string? Error);
+
+/// <summary>
+/// Thin wrapper over the WebPush library's encrypt-and-POST so that <see cref="WebPushService"/>'s
+/// recipient resolution, pruning, and logging can be unit-tested without a real push service.
+/// </summary>
+public interface IWebPushSender
+{
+    Task<WebPushSendResult> SendAsync(WebPushTarget target, string payloadJson, CancellationToken ct = default);
+}

API/ROLAC.API/Services/Notifications/IWebPushService.cs

@@ -0,0 +1,13 @@
+namespace ROLAC.API.Services.Notifications;
+
+/// <summary>
+/// The Web Push channel — peer to <see cref="IEmailService"/> and <see cref="ILineNotificationService"/>.
+/// Resolves every device subscription of the target members and pushes one notification to each,
+/// pruning subscriptions the push service reports as gone and writing a NotificationLog per send.
+/// </summary>
+public interface IWebPushService
+{
+    Task<NotificationResult> SendToMembersAsync(
+        IReadOnlyCollection<int> memberIds, WebPushPayload payload,
+        string sentByUserId, CancellationToken ct = default);
+}

API/ROLAC.API/Services/Notifications/NotificationModels.cs

@@ -3,8 +3,9 @@ namespace ROLAC.API.Services.Notifications;
 /// <summary>Canonical channel discriminators stored in NotificationLog.Channel.</summary>
 public static class NotificationChannels
 {
-    public const string Email = "email";
-    public const string Line  = "line";
+    public const string Email   = "email";
+    public const string Line    = "line";
+    public const string WebPush = "webpush";
 }
 
 /// <summary>Canonical target-type discriminators stored in NotificationLog.TargetType.</summary>
@@ -36,6 +37,12 @@ public sealed record NotificationResult(
 /// <summary>A file attached to an outbound email.</summary>
 public sealed record EmailAttachment(string FileName, string ContentType, byte[] Content);
 
+/// <summary>
+/// The content of a single Web Push notification. <see cref="Url"/> is the in-app path to open when
+/// the notification is clicked; <see cref="Tag"/> lets a newer notification replace an older one.
+/// </summary>
+public sealed record WebPushPayload(string Title, string Body, string? Url = null, string? Tag = null);
+
 /// <summary>
 /// A request to send one email to a set of members (resolved via Member.Email) and/or raw
 /// addresses. The caller supplies the final HTML body — no templating in this phase.

API/ROLAC.API/Services/Notifications/NotificationOptions.cs

@@ -18,3 +18,11 @@ public sealed class LineOptions
     public string ChannelAccessToken { get; set; } = "";
     public string ChannelSecret      { get; set; } = "";
 }
+
+/// <summary>VAPID settings for Web Push. Sourced from the NotificationSetting row at runtime.</summary>
+public sealed class WebPushOptions
+{
+    public string PublicKey  { get; set; } = "";
+    public string PrivateKey { get; set; } = "";
+    public string Subject    { get; set; } = "";
+}

API/ROLAC.API/Services/Notifications/NotificationSettingsService.cs

@@ -15,6 +15,7 @@ public interface INotificationSettingsService
 {
     SmtpOptions GetSmtp();
     LineOptions GetLine();
+    WebPushOptions GetWebPush();
     void Reload();
 }
 
@@ -27,6 +28,7 @@ public sealed class NotificationSettingsService : INotificationSettingsService
 
     private SmtpOptions? _smtp;
     private LineOptions? _line;
+    private WebPushOptions? _webPush;
 
     public NotificationSettingsService(
         IServiceScopeFactory scopeFactory,
@@ -50,12 +52,19 @@ public sealed class NotificationSettingsService : INotificationSettingsService
         return _line!;
     }
 
+    public WebPushOptions GetWebPush()
+    {
+        EnsureLoaded();
+        return _webPush!;
+    }
+
     public void Reload()
     {
         lock (_gate)
         {
             _smtp = null;
             _line = null;
+            _webPush = null;
         }
     }
 
@@ -63,7 +72,7 @@ public sealed class NotificationSettingsService : INotificationSettingsService
     {
         lock (_gate)
         {
-            if (_smtp is not null && _line is not null)
+            if (_smtp is not null && _line is not null && _webPush is not null)
                 return;
 
             using var scope = _scopeFactory.CreateScope();
@@ -72,9 +81,11 @@ public sealed class NotificationSettingsService : INotificationSettingsService
 
             if (row is null)
             {
-                // Not seeded yet — use the appsettings values so sends still work.
+                // Not seeded yet — use the appsettings values so sends still work. Web push has no
+                // appsettings fallback; it stays disabled until the row exists with VAPID keys.
                 _smtp = _smtpFallback.Value;
                 _line = _lineFallback.Value;
+                _webPush = new WebPushOptions();
                 return;
             }
 
@@ -93,6 +104,12 @@ public sealed class NotificationSettingsService : INotificationSettingsService
                 ChannelAccessToken = row.LineChannelAccessToken,
                 ChannelSecret      = row.LineChannelSecret,
             };
+            _webPush = new WebPushOptions
+            {
+                PublicKey  = row.VapidPublicKey,
+                PrivateKey = row.VapidPrivateKey,
+                Subject    = row.VapidSubject,
+            };
         }
     }
 }

API/ROLAC.API/Services/Notifications/WebPushSender.cs

@@ -0,0 +1,40 @@
+using System.Net;
+using WebPush;
+
+namespace ROLAC.API.Services.Notifications;
+
+/// <summary>
+/// Sends one encrypted Web Push message via the WebPush library, signing with the VAPID keys from
+/// the notification settings. Translates a "subscription gone" (404/410) response into
+/// <see cref="WebPushSendResult.IsExpired"/> so the caller prunes the dead subscription.
+/// </summary>
+public sealed class WebPushSender : IWebPushSender
+{
+    private readonly INotificationSettingsService _settings;
+    private readonly WebPushClient _client = new();
+
+    public WebPushSender(INotificationSettingsService settings) => _settings = settings;
+
+    public async Task<WebPushSendResult> SendAsync(
+        WebPushTarget target, string payloadJson, CancellationToken ct = default)
+    {
+        var options = _settings.GetWebPush();
+        if (string.IsNullOrWhiteSpace(options.PublicKey) || string.IsNullOrWhiteSpace(options.PrivateKey))
+            return new WebPushSendResult(Success: false, IsExpired: false, Error: "Web Push is not configured (missing VAPID keys).");
+
+        var subject = string.IsNullOrWhiteSpace(options.Subject) ? "mailto:admin@rolac.local" : options.Subject;
+        var vapid = new VapidDetails(subject, options.PublicKey, options.PrivateKey);
+        var subscription = new PushSubscription(target.Endpoint, target.P256dh, target.Auth);
+
+        try
+        {
+            await _client.SendNotificationAsync(subscription, payloadJson, vapid, ct);
+            return new WebPushSendResult(Success: true, IsExpired: false, Error: null);
+        }
+        catch (WebPushException ex)
+        {
+            var expired = ex.StatusCode is HttpStatusCode.NotFound or HttpStatusCode.Gone;
+            return new WebPushSendResult(Success: false, IsExpired: expired, Error: ex.Message);
+        }
+    }
+}

API/ROLAC.API/Services/Notifications/WebPushService.cs

@@ -0,0 +1,111 @@
+using System.Text.Json;
+using Microsoft.EntityFrameworkCore;
+using ROLAC.API.Data;
+using ROLAC.API.Entities.Notifications;
+using ROLAC.API.Services.Logging;
+
+namespace ROLAC.API.Services.Notifications;
+
+/// <summary>
+/// Resolves the target members' device subscriptions, pushes one notification to each via the
+/// <see cref="IWebPushSender"/>, prunes any subscription the push service reports as gone (404/410),
+/// and writes a NotificationLog row per send. A single failure never aborts the batch — it is
+/// recorded and reported in the summary (mirrors <see cref="EmailService"/>).
+/// </summary>
+public sealed class WebPushService : IWebPushService
+{
+    // The endpoint URL can be long; NotificationLog.TargetExternalId is capped at 200.
+    private const int TargetExternalIdMaxLength = 200;
+
+    private readonly AppDbContext _db;
+    private readonly IWebPushSender _sender;
+    private readonly CurrentUserAccessor _currentUser;
+
+    public WebPushService(AppDbContext db, IWebPushSender sender, CurrentUserAccessor currentUser)
+    {
+        _db = db;
+        _sender = sender;
+        _currentUser = currentUser;
+    }
+
+    public async Task<NotificationResult> SendToMembersAsync(
+        IReadOnlyCollection<int> memberIds, WebPushPayload payload,
+        string sentByUserId, CancellationToken ct = default)
+    {
+        if (memberIds.Count == 0) return NotificationResult.Empty;
+
+        var subscriptions = await _db.WebPushSubscriptions
+            .Where(subscription => memberIds.Contains(subscription.MemberId))
+            .ToListAsync(ct);
+        if (subscriptions.Count == 0) return NotificationResult.Empty;
+
+        var sentBy = string.IsNullOrEmpty(sentByUserId) ? _currentUser.UserIdOrSystem : sentByUserId;
+        var payloadJson = BuildPayloadJson(payload);
+        var failures = new List<NotificationFailure>();
+        var expired = new List<WebPushSubscription>();
+        var sentCount = 0;
+
+        foreach (var subscription in subscriptions)
+        {
+            var log = new NotificationLog
+            {
+                Channel          = NotificationChannels.WebPush,
+                TargetType       = NotificationTargetTypes.User,
+                TargetExternalId = TruncateEndpoint(subscription.Endpoint),
+                Subject          = payload.Title,
+                MemberId         = subscription.MemberId,
+                Body             = NotificationLogText.Truncate(payload.Body),
+                SentByUserId     = sentBy,
+                SentAt           = DateTime.UtcNow,
+            };
+
+            var result = await _sender.SendAsync(
+                new WebPushTarget(subscription.Endpoint, subscription.P256dh, subscription.Auth), payloadJson, ct);
+
+            if (result.Success)
+            {
+                log.Status = NotificationStatuses.Sent;
+                subscription.LastUsedAt = DateTime.UtcNow;
+                sentCount++;
+            }
+            else
+            {
+                log.Status = NotificationStatuses.Failed;
+                log.Error  = result.Error;
+                failures.Add(new NotificationFailure(log.TargetExternalId, result.Error ?? "unknown error"));
+                if (result.IsExpired) expired.Add(subscription);
+            }
+
+            _db.NotificationLogs.Add(log);
+        }
+
+        // Drop subscriptions the push service says are gone so they don't linger and fail forever.
+        if (expired.Count > 0) _db.WebPushSubscriptions.RemoveRange(expired);
+
+        await _db.SaveChangesAsync(ct);
+        return new NotificationResult(sentCount, failures.Count, failures);
+    }
+
+    // Shape expected by @angular/service-worker (ngsw): a top-level "notification" object whose
+    // "data.url" the app reads on click to navigate. "tag" lets a newer message replace an older one.
+    private static string BuildPayloadJson(WebPushPayload payload)
+    {
+        var notification = new Dictionary<string, object?>
+        {
+            ["title"] = payload.Title,
+            ["body"]  = payload.Body,
+            ["icon"]  = "assets/AppLogo-192.png",
+            ["data"]  = new Dictionary<string, object?>
+            {
+                ["url"] = payload.Url,
+                ["tag"] = payload.Tag,
+            },
+        };
+        if (!string.IsNullOrWhiteSpace(payload.Tag)) notification["tag"] = payload.Tag;
+
+        return JsonSerializer.Serialize(new Dictionary<string, object?> { ["notification"] = notification });
+    }
+
+    private static string TruncateEndpoint(string endpoint) =>
+        endpoint.Length <= TargetExternalIdMaxLength ? endpoint : endpoint[..TargetExternalIdMaxLength];
+}