using ZB.MOM.WW.ScadaBridge.Commons.Entities.Notifications;
using ZB.MOM.WW.ScadaBridge.Commons.Types.Enums;
using ZB.MOM.WW.ScadaBridge.ConfigurationDatabase.Repositories;

namespace ZB.MOM.WW.ScadaBridge.ConfigurationDatabase.Tests;

// Coverage for per-node KPI aggregation in the Notification Outbox repository
// (T6: M5.2 per-node stuck-count KPIs).
public class NotificationOutboxRepositoryPerNodeKpiTests
{
    private static ScadaBridgeDbContext NewContext() => SqliteTestHelper.CreateInMemoryContext();

    private static Notification NewNotification(
        string sourceSiteId,
        NotificationStatus status,
        DateTimeOffset createdAt,
        DateTimeOffset? deliveredAt = null,
        string? sourceNode = null)
    {
        return new Notification(
            Guid.NewGuid().ToString(), NotificationType.Email, "Ops List", "Subject", "Body", sourceSiteId)
        {
            Status = status,
            CreatedAt = createdAt,
            DeliveredAt = deliveredAt,
            SourceNode = sourceNode,
        };
    }

    [Fact]
    public async Task ComputePerNodeKpisAsync_AggregatesMetricsPerNode()
    {
        await using var ctx = NewContext();
        var now = DateTimeOffset.UtcNow;

        // node-a: 1 pending (stuck, created 20m ago), 1 parked
        ctx.Notifications.Add(NewNotification("plant-a", NotificationStatus.Pending,
            createdAt: now.AddMinutes(-20), sourceNode: "node-a"));
        ctx.Notifications.Add(NewNotification("plant-a", NotificationStatus.Parked,
            createdAt: now.AddMinutes(-5), sourceNode: "node-a"));
        // node-b: 1 delivered in-window, 1 pending (fresh)
        ctx.Notifications.Add(NewNotification("plant-b", NotificationStatus.Delivered,
            createdAt: now.AddHours(-2), deliveredAt: now.AddMinutes(-2), sourceNode: "node-b"));
        ctx.Notifications.Add(NewNotification("plant-b", NotificationStatus.Pending,
            createdAt: now.AddMinutes(-1), sourceNode: "node-b"));
        // NULL SourceNode — must be excluded from per-node results
        ctx.Notifications.Add(NewNotification("plant-c", NotificationStatus.Pending,
            createdAt: now.AddMinutes(-5), sourceNode: null));
        await ctx.SaveChangesAsync();

        var repo = new NotificationOutboxRepository(ctx);
        var result = await repo.ComputePerNodeKpisAsync(
            stuckCutoff: now.AddMinutes(-10), deliveredSince: now.AddMinutes(-30));

        // Only node-a and node-b — the null-node row is excluded.
        Assert.Equal(2, result.Count);

        var a = result.Single(n => n.SourceNode == "node-a");
        Assert.Equal(1, a.QueueDepth);
        Assert.Equal(1, a.StuckCount);
        Assert.Equal(1, a.ParkedCount);
        Assert.Equal(0, a.DeliveredLastInterval);
        Assert.NotNull(a.OldestPendingAge);

        var b = result.Single(n => n.SourceNode == "node-b");
        Assert.Equal(1, b.QueueDepth);
        Assert.Equal(0, b.StuckCount);
        Assert.Equal(0, b.ParkedCount);
        Assert.Equal(1, b.DeliveredLastInterval);
        Assert.NotNull(b.OldestPendingAge);
    }

    [Fact]
    public async Task ComputePerNodeKpisAsync_ExcludesNullSourceNode()
    {
        await using var ctx = NewContext();
        var now = DateTimeOffset.UtcNow;

        // Only null-node rows — result must be empty.
        ctx.Notifications.Add(NewNotification("plant-a", NotificationStatus.Pending,
            createdAt: now.AddMinutes(-5), sourceNode: null));
        await ctx.SaveChangesAsync();

        var repo = new NotificationOutboxRepository(ctx);
        var result = await repo.ComputePerNodeKpisAsync(
            stuckCutoff: now.AddMinutes(-10), deliveredSince: now.AddMinutes(-30));

        Assert.Empty(result);
    }

    [Fact]
    public async Task ComputePerNodeKpisAsync_ReturnsEmpty_WhenNoNotifications()
    {
        await using var ctx = NewContext();
        var repo = new NotificationOutboxRepository(ctx);
        var result = await repo.ComputePerNodeKpisAsync(
            DateTimeOffset.UtcNow, DateTimeOffset.UtcNow.AddMinutes(-30));
        Assert.Empty(result);
    }

    [Fact]
    public async Task ComputePerNodeKpisAsync_OldestPendingAge_ReflectsOlderRow()
    {
        await using var ctx = NewContext();
        var now = DateTimeOffset.UtcNow;

        // node-a: pending 90m ago, retrying 40m ago.
        // OldestPendingAge must reflect the 90m row.
        ctx.Notifications.Add(NewNotification("plant-a", NotificationStatus.Pending,
            createdAt: now.AddMinutes(-90), sourceNode: "node-a"));
        ctx.Notifications.Add(NewNotification("plant-a", NotificationStatus.Retrying,
            createdAt: now.AddMinutes(-40), sourceNode: "node-a"));
        await ctx.SaveChangesAsync();

        var repo = new NotificationOutboxRepository(ctx);
        var result = await repo.ComputePerNodeKpisAsync(
            stuckCutoff: now.AddMinutes(-10), deliveredSince: now.AddMinutes(-30));

        var a = result.Single(n => n.SourceNode == "node-a");
        Assert.Equal(2, a.QueueDepth);
        Assert.Equal(2, a.StuckCount);
        Assert.NotNull(a.OldestPendingAge);
        Assert.True(a.OldestPendingAge >= TimeSpan.FromMinutes(85),
            $"expected OldestPendingAge >= 85m, got {a.OldestPendingAge}");
        Assert.True(a.OldestPendingAge < TimeSpan.FromMinutes(95),
            $"expected OldestPendingAge < 95m, got {a.OldestPendingAge}");
    }
}