using System.IO;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Options;
using TermRemoteCtl.Agent.Configuration;

namespace TermRemoteCtl.Agent.Tests.Configuration;

public class AgentOptionsPipelineTests
{
    [Fact]
    public void BuildListenUri_Uses_Https_Scheme_And_HttpsPort()
    {
        var options = new AgentOptions
        {
            DataRoot = "C:\\ProgramData\\TermRemoteCtl",
            BindAddress = "127.0.0.1",
            HttpsPort = 9443,
            WebSocketFrameFlushMilliseconds = 33,
            RingBufferLineLimit = 4000
        };

        var uri = AgentEndpointConfiguration.BuildListenUri(options);

        Assert.Equal(Uri.UriSchemeHttps, uri.Scheme);
        Assert.Equal("127.0.0.1", uri.Host);
        Assert.Equal(9443, uri.Port);
    }

    [Fact]
    public void ResolveOptions_Uses_DataRoot_Fallback_When_Config_Omits_DataRoot()
    {
        var configuration = BuildConfiguration(new Dictionary<string, string?>
        {
            ["Agent:BindAddress"] = "127.0.0.1",
            ["Agent:HttpsPort"] = "9443",
            ["Agent:WebSocketFrameFlushMilliseconds"] = "33",
            ["Agent:RingBufferLineLimit"] = "4000"
        });

        var services = new ServiceCollection();
        services.AddAgentOptions(configuration);

        using var provider = services.BuildServiceProvider();
        var options = provider.GetRequiredService<IOptions<AgentOptions>>().Value;

        var expectedDataRoot = Path.Combine(
            Environment.GetFolderPath(Environment.SpecialFolder.CommonApplicationData),
            "TermRemoteCtl");

        Assert.Equal(expectedDataRoot, options.DataRoot);
    }

    [Theory]
    [InlineData("0", "33", "HttpsPort")]
    [InlineData("9443", "0", "WebSocketFrameFlushMilliseconds")]
    [InlineData("9443", "33", "RingBufferLineLimit")]
    public void ResolveOptions_Fails_When_Config_Is_Invalid(
        string httpsPort,
        string flushMilliseconds,
        string expectedFailure)
    {
        var configuration = BuildConfiguration(new Dictionary<string, string?>
        {
            ["Agent:BindAddress"] = "127.0.0.1",
            ["Agent:HttpsPort"] = httpsPort,
            ["Agent:WebSocketFrameFlushMilliseconds"] = flushMilliseconds,
            ["Agent:RingBufferLineLimit"] = expectedFailure == "RingBufferLineLimit" ? "0" : "4000"
        });

        var services = new ServiceCollection();
        services.AddAgentOptions(configuration);

        using var provider = services.BuildServiceProvider();

        var exception = Assert.Throws<OptionsValidationException>(
            () => provider.GetRequiredService<IOptions<AgentOptions>>().Value);

        Assert.Contains(exception.Failures, failure => failure.Contains(expectedFailure));
    }

    private static IConfiguration BuildConfiguration(IReadOnlyDictionary<string, string?> values)
    {
        return new ConfigurationBuilder()
            .AddInMemoryCollection(values)
            .Build();
    }
}