using System.Diagnostics;

namespace NATS.Server.Tests;

public class JetStreamApiInventoryTests
{
    [Fact]
    public void Go_inventory_contains_api_subjects_not_yet_mapped_in_dotnet()
    {
        var inventory = JetStreamApiInventory.LoadFromGoConstants();
        inventory.GoSubjects.ShouldContain("$JS.API.STREAM.UPDATE.*");
        inventory.GoSubjects.ShouldContain("$JS.API.CONSUMER.MSG.NEXT.*.*");
        inventory.GoSubjects.Count.ShouldBeGreaterThan(20);
    }
}

internal sealed class JetStreamApiInventory
{
    public IReadOnlyList<string> GoSubjects { get; }

    private JetStreamApiInventory(IReadOnlyList<string> goSubjects)
    {
        GoSubjects = goSubjects;
    }

    public static JetStreamApiInventory LoadFromGoConstants()
    {
        var script = Path.Combine(AppContext.BaseDirectory, "../../../../../scripts/jetstream/extract-go-js-api.sh");
        script = Path.GetFullPath(script);
        if (!File.Exists(script))
            throw new FileNotFoundException($"missing script: {script}");

        var psi = new ProcessStartInfo
        {
            FileName = "bash",
            RedirectStandardOutput = true,
            RedirectStandardError = true,
        };
        psi.ArgumentList.Add(script);

        using var process = Process.Start(psi) ?? throw new InvalidOperationException("failed to start inventory script");
        var output = process.StandardOutput.ReadToEnd();
        var errors = process.StandardError.ReadToEnd();
        process.WaitForExit();

        if (process.ExitCode != 0)
            throw new InvalidOperationException($"inventory script failed: {errors}");

        var subjects = output
            .Split('\n', StringSplitOptions.RemoveEmptyEntries | StringSplitOptions.TrimEntries)
            .ToList();

        return new JetStreamApiInventory(subjects);
    }
}
