using Microsoft.EntityFrameworkCore;
using ZB.MOM.WW.ScadaBridge.Commons.Entities.Deployment;
using ZB.MOM.WW.ScadaBridge.Commons.Entities.Instances;
using ZB.MOM.WW.ScadaBridge.Commons.Entities.Sites;
using ZB.MOM.WW.ScadaBridge.Commons.Entities.Templates;
using ZB.MOM.WW.ScadaBridge.Commons.Types.Enums;
using ZB.MOM.WW.ScadaBridge.ConfigurationDatabase.Repositories;

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

/// <summary>
/// Coverage for <c>IDeploymentManagerRepository.GetDeployedRevisionHashesAsync</c> — the
/// fleet-wide InstanceId → RevisionHash projection the pending-updates aggregate reads once
/// per cache TTL. Uses the shared SQLite in-memory fixture with real FK enforcement.
/// </summary>
public class DeployedRevisionHashesRepositoryTests : IDisposable
{
    private readonly ScadaBridgeDbContext _context;
    private readonly DeploymentManagerRepository _repository;

    /// <summary>Creates the in-memory context and the repository under test.</summary>
    public DeployedRevisionHashesRepositoryTests()
    {
        _context = SqliteTestHelper.CreateInMemoryContext();
        _repository = new DeploymentManagerRepository(_context);
    }

    /// <summary>Closes and disposes the in-memory context.</summary>
    public void Dispose()
    {
        _context.Database.CloseConnection();
        _context.Dispose();
        GC.SuppressFinalize(this);
    }

    private async Task<int> SeedInstanceAsync(string uniqueName)
    {
        var site = new Site($"Site-{uniqueName}", $"SI-{uniqueName}");
        var template = new Template($"T-{uniqueName}");
        _context.Sites.Add(site);
        _context.Templates.Add(template);
        await _context.SaveChangesAsync();

        var instance = new Instance(uniqueName)
        {
            SiteId = site.Id,
            TemplateId = template.Id,
            State = InstanceState.Enabled,
        };
        _context.Instances.Add(instance);
        await _context.SaveChangesAsync();
        return instance.Id;
    }

    private async Task SeedSnapshotAsync(int instanceId, string deploymentId, string revisionHash)
    {
        var snapshot = new DeployedConfigSnapshot(deploymentId, revisionHash, "{\"big\":\"payload\"}")
        {
            InstanceId = instanceId,
        };
        _context.Set<DeployedConfigSnapshot>().Add(snapshot);
        await _context.SaveChangesAsync();
    }

    [Fact]
    public async Task GetDeployedRevisionHashes_returns_every_snapshot_keyed_by_instance()
    {
        var first = await SeedInstanceAsync("Pump-01");
        var second = await SeedInstanceAsync("Pump-02");
        await SeedSnapshotAsync(first, "dep-1", "hash-one");
        await SeedSnapshotAsync(second, "dep-2", "hash-two");

        var hashes = await _repository.GetDeployedRevisionHashesAsync();

        Assert.Equal(2, hashes.Count);
        Assert.Equal("hash-one", hashes[first]);
        Assert.Equal("hash-two", hashes[second]);
    }

    [Fact]
    public async Task GetDeployedRevisionHashes_returns_empty_when_nothing_is_deployed()
    {
        await SeedInstanceAsync("Pump-01");

        var hashes = await _repository.GetDeployedRevisionHashesAsync();

        Assert.Empty(hashes);
    }
}