using Xunit;
using OpenHarbor.MCP.Gateway.Infrastructure.Transport;
using OpenHarbor.MCP.Gateway.Core.Models;

namespace OpenHarbor.MCP.Gateway.Infrastructure.Tests.Transport;

/// <summary>
/// Unit tests for StdioServerTransport following TDD approach.
/// Tests stdio transport implementation.
/// </summary>
public class StdioServerTransportTests
{
    [Fact]
    public void Constructor_WithValidCommand_CreatesSuccessfully()
    {
        // Arrange & Act
        var transport = new StdioServerTransport("dotnet", new[] { "run" });

        // Assert
        Assert.NotNull(transport);
        Assert.False(transport.IsConnected);
    }

    [Fact]
    public void Constructor_WithNullCommand_ThrowsException()
    {
        // Arrange, Act & Assert
        Assert.Throws<ArgumentNullException>(() =>
            new StdioServerTransport(null!, new[] { "arg" }));
    }

    [Fact]
    public void IsConnected_BeforeConnect_ReturnsFalse()
    {
        // Arrange
        var transport = new StdioServerTransport("echo", new[] { "test" });

        // Act & Assert
        Assert.False(transport.IsConnected);
    }

    [Fact]
    public async Task SendRequestAsync_WithoutConnect_ThrowsException()
    {
        // Arrange
        var transport = new StdioServerTransport("echo", new[] { "test" });
        var request = new GatewayRequest { ToolName = "test" };

        // Act & Assert
        await Assert.ThrowsAsync<InvalidOperationException>(() =>
            transport.SendRequestAsync(request, CancellationToken.None));
    }

    [Fact]
    public void Dispose_MultipleTimesests_DoesNotThrow()
    {
        // Arrange
        var transport = new StdioServerTransport("echo", new[] { "test" });

        // Act & Assert
        transport.Dispose();
        transport.Dispose(); // Should not throw
    }
}