using Microsoft.AspNetCore.Mvc;
using Microsoft.AspNetCore.Mvc.RazorPages;
using ListmonkIntegration.Services;
using ListmonkIntegration.Models;
using ClosedXML.Excel;

namespace ListmonkIntegration.Pages.Subscribers
{
    public class UploadModel : PageModel
    {
        private readonly IListmonkService _listmonkService;
        private readonly ILogger<UploadModel> _logger;

        [BindProperty]
        public IFormFile? excelFile { get; set; }

        public List<Subscriber> Subscribers { get; set; } = new List<Subscriber>();
        public List<string> ColumnHeaders { get; set; } = new List<string>();
        public string Message { get; set; } = string.Empty;
        public bool IsSuccess { get; set; }

        public UploadModel(IListmonkService listmonkService, ILogger<UploadModel> logger)
        {
            _listmonkService = listmonkService;
            _logger = logger;
        }

        public void OnGet()
        {
        }

        public async Task<IActionResult> OnPostAsync(string listName)
        {
            try
            {
                _logger.LogInformation("=== Upload started ===");

                if (excelFile == null || excelFile.Length == 0)
                {
                    Message = "Файл не выбран";
                    IsSuccess = false;
                    return Page();
                }

                _logger.LogInformation($"File received: {excelFile.FileName}, Size: {excelFile.Length} bytes");

                // Ограничение размера файла (10 MB)
                if (excelFile.Length > 10 * 1024 * 1024)
                {
                    Message = "Файл слишком большой (максимум 10 MB)";
                    IsSuccess = false;
                    return Page();
                }

                // Чтение Excel файла
                _logger.LogInformation("Reading Excel file...");
                Subscribers = ReadExcelFile(excelFile);
                _logger.LogInformation($"Read {Subscribers.Count} subscribers");

                if (!Subscribers.Any())
                {
                    Message = "Не найдено подписчиков в файле";
                    IsSuccess = false;
                    return Page();
                }

                // Проверяем подключение
                _logger.LogInformation("Testing Listmonk connection...");
                if (!await _listmonkService.TestConnectionAsync())
                {
                    Message = "Нет подключения к Listmonk";
                    IsSuccess = false;
                    return Page();
                }

                // Создаем список
                _logger.LogInformation($"Creating list: {listName}");
                int listId = await _listmonkService.CreateListAsync(listName);

                // Импортируем
                _logger.LogInformation($"Importing to list {listId}...");
                await _listmonkService.ImportSubscribersAsync(new List<int> { listId }, Subscribers);

                Message = $"Успешно загружено {Subscribers.Count} подписчиков в список \"{listName}\"";
                IsSuccess = true;
                _logger.LogInformation("=== Upload completed successfully ===");
            }
            catch (Exception ex)
            {
                Message = $"Ошибка: {ex.Message}";
                IsSuccess = false;
                _logger.LogError(ex, "=== Upload failed ===");
            }

            return Page();
        }

        private List<Subscriber> ReadExcelFile(IFormFile file)
        {
            var subscribers = new List<Subscriber>();

            try
            {
                // Создаём временный файл с правильным расширением .xlsx
                var tempFilePath = Path.Combine(Path.GetTempPath(), $"{Guid.NewGuid()}.xlsx");
                _logger.LogInformation($"Temp file: {tempFilePath}");

                try
                {
                    // Сохраняем загруженный файл во временный файл
                    using (var stream = new FileStream(tempFilePath, FileMode.Create))
                    {
                        file.CopyTo(stream);
                    }

                    _logger.LogInformation("Opening workbook...");
                    using (var workbook = new XLWorkbook(tempFilePath))
                    {
                        var worksheet = workbook.Worksheet(1);
                        var firstRow = worksheet.FirstRowUsed();

                        if (firstRow == null)
                        {
                            _logger.LogWarning("Empty file");
                            return subscribers;
                        }

                        // Заголовки
                        var headers = new List<string>();
                        foreach (var cell in firstRow.Cells())
                        {
                            var header = cell.Value.ToString().Trim();
                            headers.Add(header);
                            _logger.LogInformation($"Header: {header}");
                        }

                        ColumnHeaders = headers;
                        _logger.LogInformation($"Total headers: {headers.Count}");

                        if (headers.Count < 2)
                        {
                            _logger.LogError("Need at least 2 columns");
                            return subscribers;
                        }

                        // Данные
                        var lastRow = worksheet.LastRowUsed();
                        _logger.LogInformation($"Last row: {lastRow?.RowNumber() ?? 0}");

                        for (int row = 2; row <= lastRow.RowNumber(); row++)
                        {
                            try
                            {
                                var email = worksheet.Cell(row, 1).GetValue<string>().Trim();
                                if (string.IsNullOrWhiteSpace(email))
                                {
                                    _logger.LogWarning($"Row {row}: empty email, skipping");
                                    continue;
                                }

                                var name = worksheet.Cell(row, 2).GetValue<string>().Trim();

                                var attributes = new Dictionary<string, string>();
                                for (int col = 3; col <= headers.Count; col++)
                                {
                                    var value = worksheet.Cell(row, col).GetValue<string>().Trim();
                                    if (!string.IsNullOrWhiteSpace(value))
                                    {
                                        attributes[headers[col - 1]] = value;
                                    }
                                }

                                subscribers.Add(new Subscriber
                                {
                                    Email = email,
                                    FullName = name,
                                    Attributes = attributes
                                });

                                _logger.LogInformation($"Row {row}: Added {email}");
                            }
                            catch (Exception rowEx)
                            {
                                _logger.LogWarning(rowEx, $"Skipping row {row}");
                            }
                        }
                    }
                }
                finally
                {
                    // Удаляем временный файл
                    if (System.IO.File.Exists(tempFilePath))
                    {
                        try
                        {
                            System.IO.File.Delete(tempFilePath);
                            _logger.LogInformation($"Deleted temp file: {tempFilePath}");
                        }
                        catch (Exception ex)
                        {
                            _logger.LogWarning(ex, $"Failed to delete temp file: {tempFilePath}");
                        }
                    }
                }
            }
            catch (Exception ex)
            {
                _logger.LogError(ex, "Error reading Excel");
                throw;
            }

            return subscribers;
        }
    }
}