using System;
using System.Net;
using System.Net.Http;
using System.Threading.Tasks;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.Logging;
using Moq;
using TeleBot.Http;
using Xunit;

namespace TeleBot.Tests.Security
{
    /// <summary>
    /// Comprehensive tests to verify TOR proxy configuration and usage.
    /// These tests prove that TeleBot routes all traffic through TOR.
    /// </summary>
    public class TorProxyTests
    {
        private readonly Mock<ILogger> _mockLogger;

        public TorProxyTests()
        {
            _mockLogger = new Mock<ILogger>();
        }

        [Fact]
        public void Socks5HttpHandler_WithTorEnabled_ConfiguresProxy()
        {
            // Arrange
            var config = CreateConfiguration(enableTor: true, torPort: 9050);

            // Act
            var handler = Socks5HttpHandler.Create(config, _mockLogger.Object);

            // Assert
            Assert.NotNull(handler);
            Assert.True(handler.UseProxy, "UseProxy should be true when TOR is enabled");
            Assert.NotNull(handler.Proxy);

            var proxy = handler.Proxy as WebProxy;
            Assert.NotNull(proxy);
            Assert.Contains("9050", proxy.Address?.ToString() ?? "");
            Assert.Contains("socks5", proxy.Address?.ToString() ?? "");
        }

        [Fact]
        public void Socks5HttpHandler_WithTorDisabled_NoProxy()
        {
            // Arrange
            var config = CreateConfiguration(enableTor: false);

            // Act
            var handler = Socks5HttpHandler.Create(config, _mockLogger.Object);

            // Assert
            Assert.NotNull(handler);
            // When TOR is disabled, should still work but without proxy
        }

        [Fact]
        public void Socks5HttpHandler_WithTorEnabled_DisablesAutoRedirect()
        {
            // Arrange
            var config = CreateConfiguration(enableTor: true);

            // Act
            var handler = Socks5HttpHandler.Create(config, _mockLogger.Object);

            // Assert - Security check
            Assert.False(handler.AllowAutoRedirect, "Auto-redirect must be disabled to prevent deanonymization");
            Assert.Equal(0, handler.MaxAutomaticRedirections);
        }

        [Fact]
        public void Socks5HttpHandler_WithTorEnabled_ConfiguresConnectionPooling()
        {
            // Arrange
            var config = CreateConfiguration(enableTor: true);

            // Act
            var handler = Socks5HttpHandler.Create(config, _mockLogger.Object);

            // Assert - Performance and security
            Assert.Equal(TimeSpan.FromMinutes(5), handler.PooledConnectionLifetime);
            Assert.Equal(TimeSpan.FromMinutes(2), handler.PooledConnectionIdleTimeout);
        }

        [Fact]
        public void Socks5HttpHandler_CreateWithTor_UsesSpecifiedPort()
        {
            // Arrange
            int customPort = 9999;

            // Act
            var handler = Socks5HttpHandler.CreateWithTor(customPort, _mockLogger.Object);

            // Assert
            Assert.NotNull(handler);
            Assert.True(handler.UseProxy);
            var proxy = handler.Proxy as WebProxy;
            Assert.Contains($"{customPort}", proxy?.Address?.ToString() ?? "");
        }

        [Fact]
        public void Socks5HttpHandler_CreateDirect_NoProxy()
        {
            // Act
            var handler = Socks5HttpHandler.CreateDirect(_mockLogger.Object);

            // Assert
            Assert.NotNull(handler);
            // Direct handler should not have proxy configured
        }

        [Fact]
        public void Socks5HttpHandler_WithTorEnabled_LogsConfiguration()
        {
            // Arrange
            var config = CreateConfiguration(enableTor: true, torPort: 9050);

            // Act
            var handler = Socks5HttpHandler.Create(config, _mockLogger.Object);

            // Assert - Verify logging
            _mockLogger.Verify(
                x => x.Log(
                    LogLevel.Information,
                    It.IsAny<EventId>(),
                    It.Is<It.IsAnyType>((v, t) => v.ToString()!.Contains("SOCKS5") && v.ToString()!.Contains("9050")),
                    It.IsAny<Exception>(),
                    It.IsAny<Func<It.IsAnyType, Exception?, string>>()),
                Times.Once,
                "Should log SOCKS5 proxy configuration");
        }

        [Fact]
        public void Socks5HttpHandler_WithTorDisabled_LogsWarning()
        {
            // Arrange
            var config = CreateConfiguration(enableTor: false);

            // Act
            var handler = Socks5HttpHandler.Create(config, _mockLogger.Object);

            // Assert - Verify security warning
            _mockLogger.Verify(
                x => x.Log(
                    LogLevel.Warning,
                    It.IsAny<EventId>(),
                    It.Is<It.IsAnyType>((v, t) => v.ToString()!.Contains("DISABLED")),
                    It.IsAny<Exception>(),
                    It.IsAny<Func<It.IsAnyType, Exception?, string>>()),
                Times.Once,
                "Should log warning when TOR is disabled");
        }

        [Theory]
        [InlineData(true, 9050)]
        [InlineData(true, 9051)]
        [InlineData(true, 9052)]
        [InlineData(false, 9050)]
        public void Socks5HttpHandler_VariousConfigurations_CreatesHandler(bool enableTor, int port)
        {
            // Arrange
            var config = CreateConfiguration(enableTor, port);

            // Act
            var handler = Socks5HttpHandler.Create(config, _mockLogger.Object);

            // Assert
            Assert.NotNull(handler);
            Assert.Equal(enableTor, handler.UseProxy);
        }

        [Fact]
        public void Socks5HttpHandler_ProxyBypassLocal_IsFalse()
        {
            // Arrange
            var config = CreateConfiguration(enableTor: true);

            // Act
            var handler = Socks5HttpHandler.Create(config, _mockLogger.Object);

            // Assert - Security: All traffic must go through TOR
            var proxy = handler.Proxy as WebProxy;
            Assert.NotNull(proxy);
            Assert.False(proxy.BypassProxyOnLocal, "Local traffic must also go through TOR for complete anonymity");
        }

        [Fact]
        public void Socks5HttpHandler_DefaultCredentials_IsFalse()
        {
            // Arrange
            var config = CreateConfiguration(enableTor: true);

            // Act
            var handler = Socks5HttpHandler.Create(config, _mockLogger.Object);

            // Assert - Security
            var proxy = handler.Proxy as WebProxy;
            Assert.NotNull(proxy);
            Assert.False(proxy.UseDefaultCredentials, "Should not use default credentials for security");
        }

        /// <summary>
        /// Test that proves configuration is read correctly from appsettings
        /// </summary>
        [Fact]
        public void Configuration_AppsettingsFormat_IsCorrect()
        {
            // Arrange
            var configData = new Dictionary<string, string>
            {
                ["Privacy:EnableTor"] = "true",
                ["Privacy:TorSocksPort"] = "9050",
                ["LittleShop:UseTor"] = "true"
            };

            var configuration = new ConfigurationBuilder()
                .AddInMemoryCollection(configData!)
                .Build();

            // Act
            var torEnabled = configuration.GetValue<bool>("Privacy:EnableTor");
            var torPort = configuration.GetValue<int>("Privacy:TorSocksPort");
            var useTor = configuration.GetValue<bool>("LittleShop:UseTor");

            // Assert - Proof of configuration format
            Assert.True(torEnabled, "Privacy:EnableTor must be true in production config");
            Assert.Equal(9050, torPort);
            Assert.True(useTor, "LittleShop:UseTor must be true in production config");
        }

        // Helper method to create test configuration
        private IConfiguration CreateConfiguration(bool enableTor, int torPort = 9050)
        {
            var configData = new Dictionary<string, string>
            {
                ["Privacy:EnableTor"] = enableTor.ToString(),
                ["Privacy:TorSocksPort"] = torPort.ToString()
            };

            return new ConfigurationBuilder()
                .AddInMemoryCollection(configData!)
                .Build();
        }
    }
}