using System.Linq;
using System.Threading.Tasks;
using FluentAssertions;
using Mongo2Go;
using MongoDB.Bson;
using MongoDB.Driver;
using StellaOps.Concelier.Storage.Mongo.Migrations;

namespace StellaOps.Concelier.Storage.Mongo.Tests;

public sealed class EnsureLinkNotMergeCollectionsMigrationTests : IAsyncLifetime
{
    private MongoDbRunner _runner = null!;
    private IMongoDatabase _database = null!;

    public Task InitializeAsync()
    {
        _runner = MongoDbRunner.Start(singleNodeReplSet: true);
        var client = new MongoClient(_runner.ConnectionString);
        _database = client.GetDatabase("lnm-migration-tests");
        return Task.CompletedTask;
    }

    public Task DisposeAsync()
    {
        _runner.Dispose();
        return Task.CompletedTask;
    }

    [Fact]
    public async Task CreatesCollectionsAndIndexesIdempotently()
    {
        var migration = new EnsureLinkNotMergeCollectionsMigration();

        await migration.ApplyAsync(_database, CancellationToken.None);
        await migration.ApplyAsync(_database, CancellationToken.None); // idempotent second run

        var collections = await _database.ListCollectionNames().ToListAsync();
        collections.Should().Contain(new[]
        {
            MongoStorageDefaults.Collections.AdvisoryObservations,
            MongoStorageDefaults.Collections.AdvisoryLinksets
        });

        var linksetIndexes = await _database
            .GetCollection<BsonDocument>(MongoStorageDefaults.Collections.AdvisoryLinksets)
            .Indexes.List()
            .ToListAsync();

        linksetIndexes.Should().ContainSingle(i => i["name"] == "linkset_tenant_advisory_source" && i["unique"].AsBoolean);

        var obsIndexes = await _database
            .GetCollection<BsonDocument>(MongoStorageDefaults.Collections.AdvisoryObservations)
            .Indexes.List()
            .ToListAsync();

        obsIndexes.Should().Contain(i => i["name"] == "obs_prov_sourceArtifactSha_unique" && i["unique"].AsBoolean);

        var linksetValidator = await GetValidatorAsync(MongoStorageDefaults.Collections.AdvisoryLinksets);
        linksetValidator.Should().NotBeNull();
    }

    private async Task<BsonDocument?> GetValidatorAsync(string collection)
    {
        var filter = new BsonDocument("name", collection);
        var cursor = await _database.ListCollectionsAsync(new ListCollectionsOptions { Filter = filter });
        var doc = await cursor.FirstOrDefaultAsync();
        return doc?"options"?"validator"?.AsBsonDocument;
    }
}