using System.IO.Abstractions.TestingHelpers;
using System.Text.Json;
using Quadarax.Foundation.Core.Logging;
using qdr.app.studiou.orders2printpack.EmailStorage;
using Moq;

namespace qdr.app.studiou.orders2printpack.Test
{
    [TestFixture]
    public class EmailStorageProcessorTests
    {
        private Mock<ILogger> _mockLogger;
        private Mock<ILog> _mockLog;
        private MockFileSystem _mockFileSystem;
        private EmailTemplate _emailTemplate;
        private EmailProcessorConfiguration _configuration;
        private string _testBasePath;
        private EmailStorageProcessor _processor;

        [SetUp]
        public void SetUp()
        {
            // Setup mocks
            _mockLogger = new Mock<ILogger>();
            _mockLog = new Mock<ILog>();
            _mockLogger.Setup(x => x.GetLogger(It.IsAny<Type>())).Returns(_mockLog.Object);

            // Setup test paths
            _testBasePath = @"C:\TestInput";

            // Setup mock file system with initial directory structure
            _mockFileSystem = new MockFileSystem(new Dictionary<string, MockFileData>
            {
                // Create base directory
                { _testBasePath, new MockDirectoryData() },
                // Create a test recipient directory with JPG files
                { Path.Combine(_testBasePath, "test@example.com"), new MockDirectoryData() },
                { Path.Combine(_testBasePath, "test@example.com", "1001_photo1.jpg"), new MockFileData("fake jpg content") },
                { Path.Combine(_testBasePath, "test@example.com", "1001_photo2.jpg"), new MockFileData("fake jpg content") },
                { Path.Combine(_testBasePath, "test@example.com", "1002_photo1.jpg"), new MockFileData("fake jpg content") },
            });

            // Setup email template
            _emailTemplate = new EmailTemplate
            {
                Code = "TEST_TEMPLATE",
                Subject = "Your photos are ready - Orders {{ORDERS}}",
                Body = "Hello {{RECIPIENT}},\n\nYour photos are ready for download:\n{{DOWNLOAD_LINK}}\nPassword: {{PASSWORD}}\n\nOrders: {{ORDERS}}"
            };

            // Setup configuration
            _configuration = new EmailProcessorConfiguration
            {
                TssAPIKey = "test-api-key",
                TssUrl = "https://test-tss-url.com",
                SmtpServer = "smtp.test.com",
                SmtpServerPort = 587,
                SmtpServerUser = "test@smtp.com",
                SmtpServerPassword = "test-password",
                SmtpEnableSsl = true
            };
        }

        [TearDown]
        public void TearDown()
        {
            _processor?.Dispose();
        }

        private EmailStorageProcessor CreateProcessor()
        {
            return new EmailStorageProcessor(_mockFileSystem, _testBasePath, _emailTemplate, _configuration, _mockLogger.Object);
        }

        #region Constructor Tests

        [Test]
        public void Constructor_WithValidParameters_InitializesSuccessfully()
        {
            // Act
            _processor = CreateProcessor();

            // Assert
            Assert.That(_processor, Is.Not.Null);
            Assert.That(_processor.Metadata, Is.Not.Null);
            Assert.That(_processor.Metadata.Items, Is.Not.Null);
        }

        [Test]
        public void Constructor_WithNullFileSystem_ThrowsArgumentNullException()
        {
            // Act & Assert
            Assert.Throws<ArgumentNullException>(() => 
                new EmailStorageProcessor(null, _testBasePath, _emailTemplate, _configuration, _mockLogger.Object));
        }

        [Test]
        public void Constructor_WithNullPath_ThrowsArgumentNullException()
        {
            // Act & Assert
            Assert.Throws<ArgumentNullException>(() => 
                new EmailStorageProcessor(_mockFileSystem, null, _emailTemplate, _configuration, _mockLogger.Object));
        }

        [Test]
        public void Constructor_WithNullEmailTemplate_ThrowsArgumentNullException()
        {
            // Act & Assert
            Assert.Throws<ArgumentNullException>(() => 
                new EmailStorageProcessor(_mockFileSystem, _testBasePath, null, _configuration, _mockLogger.Object));
        }

        [Test]
        public void Constructor_WithNullConfiguration_ThrowsArgumentNullException()
        {
            // Act & Assert
            Assert.Throws<ArgumentNullException>(() => 
                new EmailStorageProcessor(_mockFileSystem, _testBasePath, _emailTemplate, null, _mockLogger.Object));
        }

        [Test]
        public void Constructor_WithNullLogger_ThrowsArgumentNullException()
        {
            // Act & Assert
            Assert.Throws<ArgumentNullException>(() => 
                new EmailStorageProcessor(_mockFileSystem, _testBasePath, _emailTemplate, _configuration, null));
        }

        [Test]
        public void Constructor_CreatesRequiredDirectories()
        {
            // Act
            _processor = CreateProcessor();

            // Assert
            Assert.That(_mockFileSystem.Directory.Exists(Path.Combine(_testBasePath, ".processing")), Is.True);
            Assert.That(_mockFileSystem.Directory.Exists(Path.Combine(_testBasePath, ".sending")), Is.True);
            Assert.That(_mockFileSystem.Directory.Exists(Path.Combine(_testBasePath, ".sent")), Is.True);
        }

        [Test]
        public void Constructor_ScansExistingDirectories_CreatesMetadataItems()
        {
            // Act
            _processor = CreateProcessor();

            // Assert
            Assert.That(_processor.Metadata.Items.Count, Is.EqualTo(1));
            
            var item = _processor.Metadata.Items.First();
            Assert.That(item.DirectoryName, Is.EqualTo("test@example.com"));
            Assert.That(item.EmailAddress, Is.EqualTo("test@example.com"));
            Assert.That(item.State, Is.EqualTo(EmailStateEnum.Ready));
            Assert.That(item.InternalFilesCount, Is.EqualTo(3));
            Assert.That(item.Orders, Is.EqualTo("1001,1002"));
        }

        #endregion

        #region Property Tests

        [Test]
        public void CountTotal_ReturnsCorrectCount()
        {
            // Arrange
            _processor = CreateProcessor();

            // Act
            var count = _processor.CountTotal;

            // Assert
            Assert.That(count, Is.EqualTo(1));
        }

        [Test]
        public void CountProcessing_WithProcessingItems_ReturnsCorrectCount()
        {
            // Arrange
            _processor = CreateProcessor();
            _processor.Metadata.Items.First().State = EmailStateEnum.Processing;

            // Act
            var count = _processor.CountProcessing;

            // Assert
            Assert.That(count, Is.EqualTo(1));
        }

        [Test]
        public void CountSending_WithSendingItems_ReturnsCorrectCount()
        {
            // Arrange
            _processor = CreateProcessor();
            _processor.Metadata.Items.First().State = EmailStateEnum.Sending;

            // Act
            var count = _processor.CountSending;

            // Assert
            Assert.That(count, Is.EqualTo(1));
        }

        [Test]
        public void CountSent_WithSentItems_ReturnsCorrectCount()
        {
            // Arrange
            _processor = CreateProcessor();
            _processor.Metadata.Items.First().State = EmailStateEnum.Sent;

            // Act
            var count = _processor.CountSent;

            // Assert
            Assert.That(count, Is.EqualTo(1));
        }

        #endregion

        #region ResetItem Tests

        [Test]
        public void ResetItem_WithValidRecipient_ResetsItemToReadyState()
        {
            // Arrange
            _processor = CreateProcessor();
            var item = _processor.Metadata.Items.First();
            item.State = EmailStateEnum.Error;
            item.FileNameAttachment = "test.zip";
            item.SizeAttachment = 1000;
            item.UploadPermalink = "http://test.com";
            item.DownloadPassword = "password";
            item.ProcessedDate = DateTime.Now;
            item.SentDate = DateTime.Now;
            item.ErrorMessage = "Test error";

            // Act
            _processor.ResetItem("test@example.com");

            // Assert
            Assert.That(item.State, Is.EqualTo(EmailStateEnum.Ready));
            Assert.That(item.FileNameAttachment, Is.EqualTo(string.Empty));
            Assert.That(item.SizeAttachment, Is.EqualTo(0));
            Assert.That(item.UploadPermalink, Is.EqualTo(string.Empty));
            Assert.That(item.DownloadPassword, Is.EqualTo(string.Empty));
            Assert.That(item.ProcessedDate, Is.Null);
            Assert.That(item.SentDate, Is.Null);
            Assert.That(item.ErrorMessage, Is.Null);
        }

        [Test]
        public void ResetItem_WithNonExistentRecipient_LogsWarning()
        {
            // Arrange
            _processor = CreateProcessor();

            // Act
            _processor.ResetItem("nonexistent@example.com");

            // Assert
            _mockLog.Verify(x => x.Log(LogSeverityEnum.Warn, It.IsAny<string>()), Times.Once);
        }

        [Test]
        public void ResetItem_CleansUpAssociatedFiles()
        {
            // Arrange
            _processor = CreateProcessor();
            var item = _processor.Metadata.Items.First();
            item.FileNameAttachment = "test.zip";
            
            // Create test files in processing, sending, and sent directories
            var processingFile = Path.Combine(_testBasePath, ".processing", "test.zip");
            var sendingFile = Path.Combine(_testBasePath, ".sending", "test.zip");
            var sentFile = Path.Combine(_testBasePath, ".sent", "test.zip");
            
            _mockFileSystem.AddFile(processingFile, new MockFileData("test"));
            _mockFileSystem.AddFile(sendingFile, new MockFileData("test"));
            _mockFileSystem.AddFile(sentFile, new MockFileData("test"));

            // Act
            _processor.ResetItem("test@example.com");

            // Assert
            Assert.That(_mockFileSystem.File.Exists(processingFile), Is.False);
            Assert.That(_mockFileSystem.File.Exists(sendingFile), Is.False);
            Assert.That(_mockFileSystem.File.Exists(sentFile), Is.False);
        }

        #endregion

        #region ProcessItemAsync Tests

        [Test]
        public async Task ProcessItemAsync_WithNonExistentRecipient_LogsErrorAndReturns()
        {
            // Arrange
            _processor = CreateProcessor();

            // Act
            await _processor.ProcessItemAsync("nonexistent@example.com");

            // Assert
            _mockLog.Verify(x => x.Log(LogSeverityEnum.Error, It.IsAny<string>()), Times.Once);
        }

        [Test]
        public async Task ProcessItemAsync_WithValidRecipient_UpdatesStateToProcessing()
        {
            // Arrange
            _processor = CreateProcessor();
            bool stateChangeEventFired = false;
            EmailStateEnum capturedState = EmailStateEnum.Ready;

            _processor.EmailItemStateChanged += (sender, recipient, state, progress) =>
            {
                if (state == EmailStateEnum.Processing)
                {
                    stateChangeEventFired = true;
                    capturedState = state;
                }
            };

            // Act
            try
            {
                await _processor.ProcessItemAsync("test@example.com");
            }
            catch
            {
                // Expected to fail due to missing external dependencies, but we want to check state change
            }

            // Assert
            Assert.That(stateChangeEventFired, Is.True);
            Assert.That(capturedState, Is.EqualTo(EmailStateEnum.Processing));
        }

        #endregion

        #region ProcessAllAsync Tests

        [Test]
        public async Task ProcessAllAsync_ProcessesAllReadyItems()
        {
            // Arrange
            _processor = CreateProcessor();
            
            // Add another test item
            _mockFileSystem.AddDirectory(Path.Combine(_testBasePath, "test2@example.com"));
            _mockFileSystem.AddFile(Path.Combine(_testBasePath, "test2@example.com", "2001_photo1.jpg"), new MockFileData("content"));
            
            // Recreate processor to pick up new directory
            _processor.Dispose();
            _processor = CreateProcessor();

            // Act
            try
            {
                await _processor.ProcessAllAsync();
            }
            catch
            {
                // Expected to fail due to missing external dependencies
            }

            // Assert
            // Verify that processing was attempted for all items
            _mockLog.Verify(x => x.Log(LogSeverityEnum.Info, It.Is<string>(s => s.Contains("Starting processing for recipient:"))), Times.AtLeast(1));
        }

        #endregion

        #region Stop Method Tests

        [Test]
        public void Stop_SetsCancellationToken()
        {
            // Arrange
            _processor = CreateProcessor();

            // Act
            _processor.Stop();

            // Assert
            _mockLog.Verify(x => x.Log(LogSeverityEnum.Info, "Processing stop requested."), Times.Once);
        }

        #endregion

        #region Event Tests

        [Test]
        public void EmailItemStateChanged_WhenStateUpdated_FiresEvent()
        {
            // Arrange
            _processor = CreateProcessor();
            bool eventFired = false;
            string capturedRecipient = "";
            EmailStateEnum capturedState = EmailStateEnum.Ready;
            int capturedProgress = 0;

            _processor.EmailItemStateChanged += (sender, recipient, state, progress) =>
            {
                eventFired = true;
                capturedRecipient = recipient;
                capturedState = state;
                capturedProgress = progress;
            };

            var item = _processor.Metadata.Items.First();

            // Act
            _processor.ResetItem("test@example.com"); // This should trigger state change

            // Assert
            Assert.That(eventFired, Is.True);
            Assert.That(capturedRecipient, Is.EqualTo("test@example.com"));
            Assert.That(capturedState, Is.EqualTo(EmailStateEnum.Ready));
        }

        #endregion

        #region Metadata Management Tests

        [Test]
        public void Constructor_WithExistingMetadataFile_LoadsMetadata()
        {
            // Arrange
            var existingMetadata = new Metadata
            {
                Created = DateTime.Now.AddDays(-1),
                Modified = DateTime.Now.AddHours(-1),
                Items = new List<MetadataItem>
                {
                    new MetadataItem
                    {
                        DirectoryName = "existing@example.com",
                        EmailAddress = "existing@example.com",
                        State = EmailStateEnum.Sent,
                        Subject = "Test Subject",
                        Body = "Test Body",
                        InternalFilesCount = 5,
                        Orders = "3001,3002"
                    }
                }
            };

            var metadataJson = JsonSerializer.Serialize(existingMetadata, new JsonSerializerOptions { WriteIndented = true });
            var metadataPath = Path.Combine(_testBasePath, "metadata.json");
            _mockFileSystem.AddFile(metadataPath, new MockFileData(metadataJson));

            // Act
            _processor = CreateProcessor();

            // Assert
            Assert.That(_processor.Metadata.Items.Count, Is.GreaterThan(0));
            var existingItem = _processor.Metadata.Items.FirstOrDefault(x => x.EmailAddress == "existing@example.com");
            Assert.That(existingItem, Is.Null);
            existingItem = _processor.Metadata.Items.FirstOrDefault(x => x.EmailAddress == "test@example.com");
            Assert.That(existingItem.State, Is.EqualTo(EmailStateEnum.Ready));
        }

        [Test]
        public void Constructor_ScansDirectoriesAndUpdatesMetadata()
        {
            // Arrange - metadata file exists but doesn't contain current directory
            var existingMetadata = new Metadata
            {
                Created = DateTime.Now.AddDays(-1),
                Items = new List<MetadataItem>()
            };

            var metadataJson = JsonSerializer.Serialize(existingMetadata);
            var metadataPath = Path.Combine(_testBasePath, "metadata.json");
            _mockFileSystem.AddFile(metadataPath, new MockFileData(metadataJson));

            // Act
            _processor = CreateProcessor();

            // Assert
            Assert.That(_processor.Metadata.Items.Count, Is.EqualTo(1));
            var newItem = _processor.Metadata.Items.First();
            Assert.That(newItem.DirectoryName, Is.EqualTo("test@example.com"));
            Assert.That(newItem.EmailAddress, Is.EqualTo("test@example.com"));
        }

        #endregion

        #region File Operations Tests

        [Test]
        public void Constructor_WithOrderNumbersInFilenames_ExtractsOrdersCorrectly()
        {
            // Arrange - setup files with different order patterns
            _mockFileSystem.RemoveFile(Path.Combine(_testBasePath, "test@example.com", "1001_photo1.jpg"));
            _mockFileSystem.RemoveFile(Path.Combine(_testBasePath, "test@example.com", "1001_photo2.jpg"));
            _mockFileSystem.RemoveFile(Path.Combine(_testBasePath, "test@example.com", "1002_photo1.jpg"));
            
            _mockFileSystem.AddFile(Path.Combine(_testBasePath, "test@example.com", "5001_portrait.jpg"), new MockFileData("content"));
            _mockFileSystem.AddFile(Path.Combine(_testBasePath, "test@example.com", "5002_landscape.jpg"), new MockFileData("content"));
            _mockFileSystem.AddFile(Path.Combine(_testBasePath, "test@example.com", "5001_closeup.jpg"), new MockFileData("content"));
            _mockFileSystem.AddFile(Path.Combine(_testBasePath, "test@example.com", "invalid_name.jpg"), new MockFileData("content"));

            // Act
            _processor = CreateProcessor();

            // Assert
            var item = _processor.Metadata.Items.First();
            Assert.That(item.Orders, Is.EqualTo("5001,5002")); // Should extract unique order numbers
            Assert.That(item.InternalFilesCount, Is.EqualTo(4)); // Should count all JPG files
        }

        #endregion

        #region Integration Tests

        [Test]
        public void Constructor_WithMultipleRecipientDirectories_CreatesMultipleItems()
        {
            // Arrange
            _mockFileSystem.AddDirectory(Path.Combine(_testBasePath, "user1@test.com"));
            _mockFileSystem.AddFile(Path.Combine(_testBasePath, "user1@test.com", "1001_photo.jpg"), new MockFileData("content"));
            
            _mockFileSystem.AddDirectory(Path.Combine(_testBasePath, "user2@test.com"));
            _mockFileSystem.AddFile(Path.Combine(_testBasePath, "user2@test.com", "2001_photo.jpg"), new MockFileData("content"));

            // Act
            _processor = CreateProcessor();

            // Assert
            Assert.That(_processor.Metadata.Items.Count, Is.EqualTo(3)); // Original + 2 new
            
            var emails = _processor.Metadata.Items.Select(x => x.EmailAddress).ToList();
            Assert.That(emails, Contains.Item("test@example.com"));
            Assert.That(emails, Contains.Item("user1@test.com"));
            Assert.That(emails, Contains.Item("user2@test.com"));
        }

        [Test]
        public void Constructor_IgnoresHiddenDirectories()
        {
            // Arrange
            _mockFileSystem.AddDirectory(Path.Combine(_testBasePath, ".hidden"));
            _mockFileSystem.AddFile(Path.Combine(_testBasePath, ".hidden", "1001_photo.jpg"), new MockFileData("content"));
            
            _mockFileSystem.AddDirectory(Path.Combine(_testBasePath, ".processing"));
            _mockFileSystem.AddFile(Path.Combine(_testBasePath, ".processing", "test.zip"), new MockFileData("content"));

            // Act
            _processor = CreateProcessor();

            // Assert
            // Should only have the original test@example.com directory, not the hidden ones
            Assert.That(_processor.Metadata.Items.Count, Is.EqualTo(1));
            Assert.That(_processor.Metadata.Items.First().DirectoryName, Is.EqualTo("test@example.com"));
        }

        #endregion

        #region Dispose Tests

        [Test]
        public void Dispose_DisposesResourcesProperly()
        {
            // Arrange
            _processor = CreateProcessor();

            // Act
            _processor.Dispose();

            // Assert - Should not throw
            Assert.Pass("Dispose completed without exceptions");
        }

        [Test]
        public void Dispose_CalledMultipleTimes_DoesNotThrow()
        {
            // Arrange
            _processor = CreateProcessor();

            // Act & Assert
            Assert.DoesNotThrow(() =>
            {
                _processor.Dispose();
                _processor.Dispose();
                _processor.Dispose();
            });
        }

        #endregion
    }
}