hrynco-common/HrynCo.Common.Tests/ConfigurationFactoryTests.cs

namespace HrynCo.Common.Tests;

using HrynCo.Common;
using FluentAssertions;
using Microsoft.Extensions.Configuration;
using Xunit;

public sealed class ConfigurationFactoryTests
{
    [Fact]
    public void CreateConfiguration_ShouldLoadJsonAndEnvironmentValues()
    {
        string basePath = CreateTempDirectory();
        string originalEnvironment = Environment.GetEnvironmentVariable("ASPNETCORE_ENVIRONMENT") ?? string.Empty;

        try
        {
            File.WriteAllText(Path.Combine(basePath, "appsettings.json"), """
            {
              "Title": "base",
              "Nested": {
                "Value": "base"
              }
            }
            """);

            File.WriteAllText(Path.Combine(basePath, "appsettings.Test.json"), """
            {
              "Nested": {
                "Value": "override"
              }
            }
            """);

            File.WriteAllText(Path.Combine(basePath, "local.settings.json"), """
            {
              "Local": "enabled"
            }
            """);

            Environment.SetEnvironmentVariable("ASPNETCORE_ENVIRONMENT", "Test");
            Environment.SetEnvironmentVariable("TITLE", "from-env");

            IConfigurationRoot configuration = ConfigurationFactory.CreateConfiguration(basePath);

            configuration["Title"].Should().Be("from-env");
            configuration["Nested:Value"].Should().Be("override");
            configuration["Local"].Should().Be("enabled");
        }
        finally
        {
            Environment.SetEnvironmentVariable("ASPNETCORE_ENVIRONMENT", originalEnvironment);
            Environment.SetEnvironmentVariable("TITLE", null);
            Directory.Delete(basePath, true);
        }
    }

    [Fact]
    public void CreateConfiguration_ShouldThrowWhenBasePathIsMissing()
    {
        string missingPath = Path.Combine(Path.GetTempPath(), Guid.NewGuid().ToString("N"));

        Action act = () => ConfigurationFactory.CreateConfiguration(missingPath, "Production");

        act.Should().Throw<DirectoryNotFoundException>()
            .WithMessage($"Directory {missingPath} does not exist. Wrong value of the basePath parameter.");
    }

    private static string CreateTempDirectory()
    {
        string path = Path.Combine(Path.GetTempPath(), Guid.NewGuid().ToString("N"));
        Directory.CreateDirectory(path);
        return path;
    }
}