using Shouldly;
using Xunit;

namespace ZB.MOM.WW.OtOpcUa.Driver.Galaxy.Tests;

/// <summary>
///     Follow-up #2 — pins the three resolution forms supported by
///     <see cref="GalaxyDriver.ResolveApiKey"/>: <c>env:NAME</c>, <c>file:PATH</c>,
///     and the literal-string fallback. A future DPAPI arm slots in here without
///     touching the call site.
/// </summary>
public sealed class GalaxyDriverApiKeyResolverTests
{
    [Fact]
    public void Literal_string_is_returned_unchanged()
    {
        GalaxyDriver.ResolveApiKey("plain-text-key").ShouldBe("plain-text-key");
    }

    [Fact]
    public void Env_prefix_resolves_to_environment_variable()
    {
        const string name = "OTOPCUA_TEST_GALAXY_API_KEY";
        Environment.SetEnvironmentVariable(name, "key-from-env");
        try
        {
            GalaxyDriver.ResolveApiKey($"env:{name}").ShouldBe("key-from-env");
        }
        finally
        {
            Environment.SetEnvironmentVariable(name, null);
        }
    }

    [Fact]
    public void Env_prefix_unset_variable_throws_with_descriptive_message()
    {
        const string name = "OTOPCUA_TEST_GALAXY_API_KEY_UNSET";
        Environment.SetEnvironmentVariable(name, null);

        var ex = Should.Throw<InvalidOperationException>(() =>
            GalaxyDriver.ResolveApiKey($"env:{name}"));
        ex.Message.ShouldContain(name);
        ex.Message.ShouldContain("unset");
    }

    [Fact]
    public void File_prefix_resolves_to_trimmed_file_contents()
    {
        var path = Path.Combine(Path.GetTempPath(), $"galaxy-key-{Guid.NewGuid():N}.txt");
        File.WriteAllText(path, "  key-from-file  \n");
        try
        {
            GalaxyDriver.ResolveApiKey($"file:{path}").ShouldBe("key-from-file");
        }
        finally
        {
            File.Delete(path);
        }
    }

    [Fact]
    public void File_prefix_missing_path_throws()
    {
        var path = Path.Combine(Path.GetTempPath(), $"does-not-exist-{Guid.NewGuid():N}.txt");
        var ex = Should.Throw<InvalidOperationException>(() =>
            GalaxyDriver.ResolveApiKey($"file:{path}"));
        ex.Message.ShouldContain(path);
        ex.Message.ShouldContain("doesn't exist");
    }

    [Fact]
    public void File_prefix_empty_file_throws()
    {
        var path = Path.Combine(Path.GetTempPath(), $"galaxy-key-empty-{Guid.NewGuid():N}.txt");
        File.WriteAllText(path, "   \n  ");
        try
        {
            var ex = Should.Throw<InvalidOperationException>(() =>
                GalaxyDriver.ResolveApiKey($"file:{path}"));
            ex.Message.ShouldContain("empty");
        }
        finally
        {
            File.Delete(path);
        }
    }
}