using FluentAssertions;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Options;
using StellaOps.Router.Gateway.Configuration;
using StellaOps.Router.Gateway.DependencyInjection;
using Xunit;

namespace StellaOps.Router.Gateway.Tests;

public sealed class RouterNodeConfigValidationTests
{
    [Fact]
    public void RouterNodeConfig_WhenRegionMissing_ThrowsOptionsValidationException()
    {
        var services = new ServiceCollection();
        services.AddRouterGatewayCore();

        using var provider = services.BuildServiceProvider();

        var act = () => provider.GetRequiredService<IOptions<RouterNodeConfig>>().Value;

        act.Should().Throw<OptionsValidationException>();
    }

    [Fact]
    public void RouterNodeConfig_WhenRegionProvided_GeneratesNodeIdIfMissing()
    {
        var services = new ServiceCollection();
        services.AddRouterGatewayCore();
        services.Configure<RouterNodeConfig>(c => c.Region = "test");

        using var provider = services.BuildServiceProvider();

        var config = provider.GetRequiredService<IOptions<RouterNodeConfig>>().Value;

        config.Region.Should().Be("test");
        config.NodeId.Should().StartWith("gw-test-");
        config.NodeId.Should().HaveLength("gw-test-".Length + 8);
    }
}