using BuildFlow.Platform.Application.Notifications.Commands;
using BuildFlow.Platform.Application.Notifications.Handlers;
using BuildFlow.Platform.Application.Notifications.Queries;
using BuildFlow.Platform.Domain.Entities;
using BuildFlow.Platform.Infrastructure.Persistence;
using FluentAssertions;
using Microsoft.EntityFrameworkCore;
using NSubstitute;
using Xunit;
using INotificationDispatcher = BuildFlow.Platform.Application.Notifications.INotificationDispatcher;

namespace BuildFlow.Platform.Tests.Notifications;

/// <summary>
/// [SOP-PLATFORM-02] 通知系统全 Handler 覆盖测试。
/// 覆盖:Publish(Fanout) / GetNotifications(分页) / GetUnreadCount / MarkRead / MarkAllRead。
/// 飞书矩阵: platform/Notifications 子域(5 Handler 零覆盖→全补)
/// </summary>
public class NotificationHandlerTests
{
    private static PlatformDbContext CreateDb([System.Runtime.CompilerServices.CallerMemberName] string name = "")
        => PlatformTestDb.CreateDbContext(name);

    private static Notification NewNotification(Guid recipient, bool read = false, string type = "system")
        => PlatformTestDb.WithAudit(new Notification
        {
            RecipientUserId = recipient,
            Type = type,
            Title = "测试通知",
            Content = "内容",
            Source = "system",
            IsRead = read,
            ReadAt = read ? DateTime.UtcNow : null
        });

    [Fact]
    public async Task Publish_WithRecipientUserIds_FanoutAndDispatch()
    {
        var db = CreateDb();
        var dispatcher = Substitute.For<INotificationDispatcher>();
        var u1 = Guid.NewGuid();
        var u2 = Guid.NewGuid();
        var handler = new PublishNotificationCommandHandler(db, dispatcher);

        var count = await handler.Handle(new PublishNotificationCommand(
            "task-arrived", "标题", "内容", "workflow", null, "workflow-instance",
            new[] { u1, u2 }, null), CancellationToken.None);

        count.Should().Be(2);
        (await db.Notifications.IgnoreQueryFilters().ToListAsync())
            .Should().HaveCount(2);
        await dispatcher.Received(1).DispatchAsync(
            Arg.Is<IReadOnlyList<Notification>>(l => l.Count == 2),
            Arg.Any<CancellationToken>());
    }

    [Fact]
    public async Task Publish_NoRecipients_ReturnsZeroAndNoDispatch()
    {
        var db = CreateDb();
        var dispatcher = Substitute.For<INotificationDispatcher>();
        var handler = new PublishNotificationCommandHandler(db, dispatcher);

        var count = await handler.Handle(new PublishNotificationCommand(
            "system", "t", "c", "system", null, null, null, null), CancellationToken.None);

        count.Should().Be(0);
        await dispatcher.DidNotReceiveWithAnyArgs().DispatchAsync(default!, default);
    }

    [Fact]
    public async Task GetNotifications_Paginated_ReturnsUserOnly()
    {
        var db = CreateDb();
        var me = Guid.NewGuid();
        var other = Guid.NewGuid();
        db.Notifications.AddRange(NewNotification(me), NewNotification(me), NewNotification(other));
        await db.SaveChangesAsync();
        var handler = new GetNotificationsQueryHandler(db);

        var result = await handler.Handle(
            new GetNotificationsQuery(me, false, 1, 10), CancellationToken.None);

        result.Items.Should().HaveCount(2);
        result.Items.Should().OnlyContain(n => n.RecipientUserId == me);
        result.Total.Should().Be(2);
    }

    [Fact]
    public async Task GetNotifications_UnreadOnly_FiltersRead()
    {
        var db = CreateDb();
        var me = Guid.NewGuid();
        db.Notifications.AddRange(NewNotification(me, read: true), NewNotification(me, read: false));
        await db.SaveChangesAsync();
        var handler = new GetNotificationsQueryHandler(db);

        var result = await handler.Handle(
            new GetNotificationsQuery(me, true, 1, 10), CancellationToken.None);

        result.Items.Should().HaveCount(1);
        result.Items[0].IsRead.Should().BeFalse();
    }

    [Fact]
    public async Task GetUnreadCount_ReturnsOnlyUnread()
    {
        var db = CreateDb();
        var me = Guid.NewGuid();
        db.Notifications.AddRange(
            NewNotification(me, read: false),
            NewNotification(me, read: false),
            NewNotification(me, read: true));
        await db.SaveChangesAsync();
        var handler = new GetUnreadNotificationCountQueryHandler(db);

        var count = await handler.Handle(new GetUnreadNotificationCountQuery(me), CancellationToken.None);

        count.Should().Be(2);
    }

    [Fact]
    public async Task MarkRead_ExistingUnread_MarksAndReturnsTrue()
    {
        var db = CreateDb();
        var me = Guid.NewGuid();
        var n = NewNotification(me, read: false);
        db.Notifications.Add(n);
        await db.SaveChangesAsync();
        var handler = new MarkNotificationReadCommandHandler(db);

        var ok = await handler.Handle(new MarkNotificationReadCommand(n.Id, me), CancellationToken.None);

        ok.Should().BeTrue();
        (await db.Notifications.FindAsync(n.Id))!.IsRead.Should().BeTrue();
    }

    [Fact]
    public async Task MarkRead_NonExistent_ReturnsFalse()
    {
        var db = CreateDb();
        var handler = new MarkNotificationReadCommandHandler(db);

        var ok = await handler.Handle(
            new MarkNotificationReadCommand(Guid.NewGuid(), Guid.NewGuid()), CancellationToken.None);

        ok.Should().BeFalse();
    }

    [Fact]
    public async Task MarkAllRead_MarksAllForUser()
    {
        var db = CreateDb();
        var me = Guid.NewGuid();
        var other = Guid.NewGuid();
        db.Notifications.AddRange(
            NewNotification(me, read: false),
            NewNotification(me, read: false),
            NewNotification(other, read: false));
        await db.SaveChangesAsync();
        var handler = new MarkAllNotificationsReadCommandHandler(db);

        var affected = await handler.Handle(new MarkAllNotificationsReadCommand(me), CancellationToken.None);

        affected.Should().Be(2);
        (await db.Notifications.CountAsync(n => n.RecipientUserId == me && !n.IsRead)).Should().Be(0);
    }
}