using System.Collections.Generic;
using System.ComponentModel.DataAnnotations;
using System.Threading;
using System.Threading.Tasks;
using StellaOps.Scheduler.Models;
using StellaOps.Scheduler.WebService.GraphJobs;
using Xunit;

namespace StellaOps.Scheduler.WebService.Tests;

public sealed class GraphJobServiceTests
{
    private static readonly DateTimeOffset FixedTime = new(2025, 11, 4, 12, 0, 0, TimeSpan.Zero);

    [Fact]
    public async Task CompleteBuildJob_PersistsMetadataAndPublishesOnce()
    {
        var store = new TrackingGraphJobStore();
        var initial = CreateBuildJob();
        await store.AddAsync(initial, CancellationToken.None);

        var clock = new FixedClock(FixedTime);
        var publisher = new RecordingPublisher();
        var webhook = new RecordingWebhookClient();
        var service = new GraphJobService(store, clock, publisher, webhook);

        var request = new GraphJobCompletionRequest
        {
            JobId = initial.Id,
            JobType = GraphJobQueryType.Build,
            Status = GraphJobStatus.Completed,
            OccurredAt = FixedTime,
            GraphSnapshotId = "graph_snap_final ",
            ResultUri = "oras://cartographer/bundle ",
            CorrelationId = "corr-123 "
        };

        var response = await service.CompleteJobAsync(initial.TenantId, request, CancellationToken.None);

        Assert.Equal(GraphJobStatus.Completed, response.Status);
        Assert.Equal(1, store.BuildUpdateCount);
        Assert.Single(publisher.Notifications);
        Assert.Single(webhook.Notifications);

        var stored = await store.GetBuildJobAsync(initial.TenantId, initial.Id, CancellationToken.None);
        Assert.NotNull(stored);
        Assert.Equal("graph_snap_final", stored!.GraphSnapshotId);
        Assert.Equal("corr-123", stored.CorrelationId);
        Assert.True(stored.Metadata.TryGetValue("resultUri", out var resultUri));
        Assert.Equal("oras://cartographer/bundle", resultUri);
    }

    [Fact]
    public async Task CompleteBuildJob_IsIdempotentWhenAlreadyCompleted()
    {
        var store = new TrackingGraphJobStore();
        var initial = CreateBuildJob();
        await store.AddAsync(initial, CancellationToken.None);

        var clock = new FixedClock(FixedTime);
        var publisher = new RecordingPublisher();
        var webhook = new RecordingWebhookClient();
        var service = new GraphJobService(store, clock, publisher, webhook);

        var request = new GraphJobCompletionRequest
        {
            JobId = initial.Id,
            JobType = GraphJobQueryType.Build,
            Status = GraphJobStatus.Completed,
            OccurredAt = FixedTime,
            GraphSnapshotId = "graph_snap_final",
            ResultUri = "oras://cartographer/bundle",
            CorrelationId = "corr-123"
        };

        await service.CompleteJobAsync(initial.TenantId, request, CancellationToken.None);
        var updateCountAfterFirst = store.BuildUpdateCount;

        var secondResponse = await service.CompleteJobAsync(initial.TenantId, request, CancellationToken.None);

        Assert.Equal(GraphJobStatus.Completed, secondResponse.Status);
        Assert.Equal(updateCountAfterFirst, store.BuildUpdateCount);
        Assert.Single(publisher.Notifications);
        Assert.Single(webhook.Notifications);
    }

    [Fact]
    public async Task CompleteBuildJob_UpdatesResultUriWithoutReemittingEvent()
    {
        var store = new TrackingGraphJobStore();
        var initial = CreateBuildJob();
        await store.AddAsync(initial, CancellationToken.None);

        var clock = new FixedClock(FixedTime);
        var publisher = new RecordingPublisher();
        var webhook = new RecordingWebhookClient();
        var service = new GraphJobService(store, clock, publisher, webhook);

        var firstRequest = new GraphJobCompletionRequest
        {
            JobId = initial.Id,
            JobType = GraphJobQueryType.Build,
            Status = GraphJobStatus.Completed,
            OccurredAt = FixedTime,
            GraphSnapshotId = "graph_snap_final",
            ResultUri = null,
            CorrelationId = "corr-123"
        };

        await service.CompleteJobAsync(initial.TenantId, firstRequest, CancellationToken.None);
        Assert.Equal(1, store.BuildUpdateCount);
        Assert.Single(publisher.Notifications);
        Assert.Single(webhook.Notifications);

        var secondRequest = firstRequest with
        {
            ResultUri = "oras://cartographer/bundle-v2",
            OccurredAt = FixedTime.AddSeconds(30)
        };

        var response = await service.CompleteJobAsync(initial.TenantId, secondRequest, CancellationToken.None);

        Assert.Equal(GraphJobStatus.Completed, response.Status);
        Assert.Equal(2, store.BuildUpdateCount);
        Assert.Single(publisher.Notifications);
        Assert.Single(webhook.Notifications);

        var stored = await store.GetBuildJobAsync(initial.TenantId, initial.Id, CancellationToken.None);
        Assert.NotNull(stored);
        Assert.True(stored!.Metadata.TryGetValue("resultUri", out var resultUri));
        Assert.Equal("oras://cartographer/bundle-v2", resultUri);
    }

    [Fact]
    public async Task CreateBuildJob_NormalizesSbomDigest()
    {
        var store = new TrackingGraphJobStore();
        var clock = new FixedClock(FixedTime);
        var publisher = new RecordingPublisher();
        var webhook = new RecordingWebhookClient();
        var service = new GraphJobService(store, clock, publisher, webhook);

        var request = new GraphBuildJobRequest
        {
            SbomId = "sbom-alpha",
            SbomVersionId = "sbom-alpha-v1",
            SbomDigest = "  SHA256:" + new string('A', 64) + "  ",
        };

        var created = await service.CreateBuildJobAsync("tenant-alpha", request, CancellationToken.None);
        Assert.Equal("sha256:" + new string('a', 64), created.SbomDigest);
    }

    [Fact]
    public async Task CreateBuildJob_RejectsDigestWithoutPrefix()
    {
        var store = new TrackingGraphJobStore();
        var clock = new FixedClock(FixedTime);
        var publisher = new RecordingPublisher();
        var webhook = new RecordingWebhookClient();
        var service = new GraphJobService(store, clock, publisher, webhook);

        var request = new GraphBuildJobRequest
        {
            SbomId = "sbom-alpha",
            SbomVersionId = "sbom-alpha-v1",
            SbomDigest = new string('a', 64),
        };

        var ex = await Assert.ThrowsAsync<ValidationException>(
            async () => await service.CreateBuildJobAsync("tenant-alpha", request, CancellationToken.None));
        Assert.Contains("sha256:", ex.Message, StringComparison.Ordinal);
    }

    private static GraphBuildJob CreateBuildJob()
    {
        var digest = "sha256:" + new string('a', 64);
        return new GraphBuildJob(
            id: "gbj_test",
            tenantId: "tenant-alpha",
            sbomId: "sbom-alpha",
            sbomVersionId: "sbom-alpha-v1",
            sbomDigest: digest,
            status: GraphJobStatus.Pending,
            trigger: GraphBuildJobTrigger.SbomVersion,
            createdAt: FixedTime,
            metadata: null);
    }

    private sealed class TrackingGraphJobStore : IGraphJobStore
    {
        private readonly InMemoryGraphJobStore _inner = new();

        public int BuildUpdateCount { get; private set; }

        public int OverlayUpdateCount { get; private set; }

        public ValueTask<GraphBuildJob> AddAsync(GraphBuildJob job, CancellationToken cancellationToken)
            => _inner.AddAsync(job, cancellationToken);

        public ValueTask<GraphOverlayJob> AddAsync(GraphOverlayJob job, CancellationToken cancellationToken)
            => _inner.AddAsync(job, cancellationToken);

        public ValueTask<GraphJobCollection> GetJobsAsync(string tenantId, GraphJobQuery query, CancellationToken cancellationToken)
            => _inner.GetJobsAsync(tenantId, query, cancellationToken);

        public ValueTask<GraphBuildJob?> GetBuildJobAsync(string tenantId, string jobId, CancellationToken cancellationToken)
            => _inner.GetBuildJobAsync(tenantId, jobId, cancellationToken);

        public ValueTask<GraphOverlayJob?> GetOverlayJobAsync(string tenantId, string jobId, CancellationToken cancellationToken)
            => _inner.GetOverlayJobAsync(tenantId, jobId, cancellationToken);

        public async ValueTask<GraphJobUpdateResult<GraphBuildJob>> UpdateAsync(GraphBuildJob job, GraphJobStatus expectedStatus, CancellationToken cancellationToken)
        {
            BuildUpdateCount++;
            return await _inner.UpdateAsync(job, expectedStatus, cancellationToken);
        }

        public async ValueTask<GraphJobUpdateResult<GraphOverlayJob>> UpdateAsync(GraphOverlayJob job, GraphJobStatus expectedStatus, CancellationToken cancellationToken)
        {
            OverlayUpdateCount++;
            return await _inner.UpdateAsync(job, expectedStatus, cancellationToken);
        }

        public ValueTask<IReadOnlyCollection<GraphOverlayJob>> GetOverlayJobsAsync(string tenantId, CancellationToken cancellationToken)
            => _inner.GetOverlayJobsAsync(tenantId, cancellationToken);
    }

    private sealed class RecordingPublisher : IGraphJobCompletionPublisher
    {
        public List<GraphJobCompletionNotification> Notifications { get; } = new();

        public Task PublishAsync(GraphJobCompletionNotification notification, CancellationToken cancellationToken)
        {
            Notifications.Add(notification);
            return Task.CompletedTask;
        }
    }

    private sealed class RecordingWebhookClient : ICartographerWebhookClient
    {
        public List<GraphJobCompletionNotification> Notifications { get; } = new();

        public Task NotifyAsync(GraphJobCompletionNotification notification, CancellationToken cancellationToken)
        {
            Notifications.Add(notification);
            return Task.CompletedTask;
        }
    }

    private sealed class FixedClock : ISystemClock
    {
        public FixedClock(DateTimeOffset utcNow)
        {
            UtcNow = utcNow;
        }

        public DateTimeOffset UtcNow { get; set; }
    }
}