using Aspire.Hosting;
using Aspire.Hosting.ApplicationModel;
using Aspire.Hosting.Testing;

namespace RoslynStone.AppHost.Tests;

/// <summary>
/// Integration tests for the Roslyn-Stone AppHost Aspire configuration.
/// These tests verify that the distributed application starts correctly and
/// that the MCP server HTTP endpoint is accessible.
/// </summary>
[Trait("Category", "Integration")]
[Trait("Component", "Aspire")]
public class AppHostTests
{
    [Fact]
    public async Task AppHost_CreatesSuccessfully()
    {
        // Arrange & Act
        var appHost =
            await DistributedApplicationTestingBuilder.CreateAsync<Projects.RoslynStone_AppHost>();

        // Assert
        Assert.NotNull(appHost);
    }

    [Fact]
    public async Task McpServer_HasHttpEndpoint()
    {
        // Arrange
        var appHost =
            await DistributedApplicationTestingBuilder.CreateAsync<Projects.RoslynStone_AppHost>();

        // Act
        var mcpServer = appHost
            .Resources.OfType<IResourceWithEndpoints>()
            .FirstOrDefault(r => r.Name == "roslyn-stone-mcp");

        // Assert
        Assert.NotNull(mcpServer);
        var endpoints = mcpServer.GetEndpoints();
        // The MCP server uses the default 'http' endpoint; ensure it's present.
        Assert.Contains(endpoints, e => e.EndpointName == "http");
    }

    [Fact]
    public async Task McpServer_HasCorrectEnvironmentVariables()
    {
        // Arrange
        var appHost =
            await DistributedApplicationTestingBuilder.CreateAsync<Projects.RoslynStone_AppHost>();

        // Act
        var mcpServer = appHost
            .Resources.OfType<IResourceWithEnvironment>()
            .FirstOrDefault(r => r.Name == "roslyn-stone-mcp");

        // Assert
        Assert.NotNull(mcpServer);
        var env = await mcpServer.GetEnvironmentVariableValuesAsync(
            DistributedApplicationOperation.Publish
        );

        Assert.True(env.TryGetValue("MCP_TRANSPORT", out var mcpTransport));
        Assert.Equal("http", mcpTransport);
        Assert.True(env.TryGetValue("OTEL_SERVICE_NAME", out var otelServiceName));
        Assert.Equal("roslyn-stone-mcp", otelServiceName);
    }

    [Fact]
    public async Task McpServer_IsConfiguredAsProjectResource()
    {
        // Arrange
        var appHost =
            await DistributedApplicationTestingBuilder.CreateAsync<Projects.RoslynStone_AppHost>();

        // Act
        var mcpServer = appHost.Resources.FirstOrDefault(r => r.Name == "roslyn-stone-mcp");

        // Assert
        Assert.NotNull(mcpServer);
        Assert.IsAssignableFrom<ProjectResource>(mcpServer);
    }

    [Fact]
    public async Task McpServer_DoesNotHaveStdioTransport()
    {
        // Arrange
        var appHost =
            await DistributedApplicationTestingBuilder.CreateAsync<Projects.RoslynStone_AppHost>();

        // Act - there should only be one resource named "roslyn-stone-mcp"
        var mcpServers = appHost
            .Resources.Where(r =>
                r.Name.Contains("roslyn-stone-mcp", StringComparison.OrdinalIgnoreCase)
            )
            .ToList();

        // Assert - verify only HTTP transport is configured (no stdio)
        Assert.Single(mcpServers);
        Assert.Equal("roslyn-stone-mcp", mcpServers[0].Name);
    }

    [Fact]
    public async Task McpInspector_IsConfiguredInDevelopment()
    {
        // Arrange
        var appHost =
            await DistributedApplicationTestingBuilder.CreateAsync<Projects.RoslynStone_AppHost>();

        // Act
        var inspector = appHost.Resources.FirstOrDefault(r => r.Name == "mcp-inspector");

        // Assert - inspector should be present in development mode (default for tests)
        Assert.NotNull(inspector);
        Assert.IsAssignableFrom<ExecutableResource>(inspector);
    }

    [Fact]
    public async Task McpInspector_HasUiAndProxyEndpoints()
    {
        // Arrange
        var appHost =
            await DistributedApplicationTestingBuilder.CreateAsync<Projects.RoslynStone_AppHost>();

        // Act
        var inspector = appHost
            .Resources.OfType<IResourceWithEndpoints>()
            .FirstOrDefault(r => r.Name == "mcp-inspector");

        // Assert
        Assert.NotNull(inspector);
        var endpoints = inspector.GetEndpoints().ToList();
        Assert.Contains(endpoints, e => e.EndpointName == "client");
        Assert.Contains(endpoints, e => e.EndpointName == "server-proxy");
    }
}