using System;
using System.IO;
using System.Threading;
using System.Threading.Tasks;
using StellaOps.Scanner.Cache.Abstractions;
using StellaOps.Scanner.Surface.Env;
using StellaOps.Scanner.Reachability.Gates;

namespace StellaOps.Scanner.Reachability;

public interface IRichGraphPublisherService
{
    Task<RichGraphPublishResult> PublishAsync(ReachabilityUnionGraph graph, string analysisId, CancellationToken cancellationToken = default);
}

/// <summary>
/// Service wrapper that builds richgraph-v1 from a union graph and stores it in CAS.
/// </summary>
public sealed class ReachabilityRichGraphPublisherService : IRichGraphPublisherService
{
    private readonly ISurfaceEnvironment _environment;
    private readonly IFileContentAddressableStore _cas;
    private readonly IRichGraphPublisher _publisher;
    private readonly IRichGraphGateAnnotator? _gateAnnotator;

    public ReachabilityRichGraphPublisherService(
        ISurfaceEnvironment environment,
        IFileContentAddressableStore cas,
        IRichGraphPublisher publisher,
        IRichGraphGateAnnotator? gateAnnotator = null)
    {
        _environment = environment ?? throw new ArgumentNullException(nameof(environment));
        _cas = cas ?? throw new ArgumentNullException(nameof(cas));
        _publisher = publisher ?? throw new ArgumentNullException(nameof(publisher));
        _gateAnnotator = gateAnnotator;
    }

    public async Task<RichGraphPublishResult> PublishAsync(ReachabilityUnionGraph graph, string analysisId, CancellationToken cancellationToken = default)
    {
        var richGraph = RichGraphBuilder.FromUnion(graph, "scanner.reachability", "0.1.0");
        if (_gateAnnotator is not null)
        {
            richGraph = await _gateAnnotator.AnnotateAsync(richGraph, cancellationToken).ConfigureAwait(false);
        }

        var workRoot = Path.Combine(_environment.Settings.CacheRoot.FullName, "reachability");
        Directory.CreateDirectory(workRoot);
        return await _publisher.PublishAsync(richGraph, analysisId, _cas, workRoot, cancellationToken).ConfigureAwait(false);
    }
}