using SQLVision.Core.Enums;
using SQLVision.Core.Interfaces;
using SQLVision.Core.Models;
using System;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.Data;
using System.Linq;
using System.Text;
using System.Text.Json;
using System.Threading.Tasks;
using Windows.ApplicationModel.DataTransfer;

namespace SQLVision.UI.ViewModels;

public class MainViewModel : ObservableObject
{
    private readonly IScriptManager _scriptManager;
    private readonly ISqlExecutionService _executionService;
    private readonly IExportService _exportService;
    private readonly IControlFactory _controlFactory;
    private readonly IVisualizerFactory _visualizerFactory;
    private readonly ILogger<MainViewModel> _logger;

    private readonly ObservableCollection<ScriptMetadata> _scripts = new();
    private readonly ObservableCollection<ScriptCategory> _scriptCategories = new();
    private readonly ObservableCollection<ExecutionHistoryItem> _history = new();
    private readonly ObservableCollection<ResultTabViewModel> _resultTabs = new();

    private ScriptMetadata _selectedScript;
    private bool _isBusy;
    private string _statusMessage;
    private ResultTabViewModel _selectedResultTab;
    private string _searchText;

    public ObservableCollection<ScriptCategory> ScriptCategories => _scriptCategories;
    public ObservableCollection<ExecutionHistoryItem> History => _history;
    public ObservableCollection<ResultTabViewModel> ResultTabs => _resultTabs;

    public ScriptMetadata SelectedScript
    {
        get => _selectedScript;
        set
        {
            if (SetProperty(ref _selectedScript, value))
            {
                OnSelectedScriptChanged();
            }
        }
    }

    public bool IsBusy
    {
        get => _isBusy;
        set => SetProperty(ref _isBusy, value);
    }

    public string StatusMessage
    {
        get => _statusMessage;
        set => SetProperty(ref _statusMessage, value);
    }

    public ResultTabViewModel SelectedResultTab
    {
        get => _selectedResultTab;
        set => SetProperty(ref _selectedResultTab, value);
    }

    public string SearchText
    {
        get => _searchText;
        set
        {
            if (SetProperty(ref _searchText, value))
            {
                FilterScripts();
            }
        }
    }

    public ObservableCollection<ParameterViewModel> Parameters { get; } = new();

    public IAsyncRelayCommand LoadScriptsCommand { get; }
    public IAsyncRelayCommand ExecuteCommand { get; }
    public IAsyncRelayCommand ExportCommand { get; }
    public IRelayCommand CopySqlCommand { get; }
    public IRelayCommand ClearResultsCommand { get; }
    public IRelayCommand SaveParametersCommand { get; }
    public IRelayCommand LoadParametersCommand { get; }

    public MainViewModel(
        IScriptManager scriptManager,
        ISqlExecutionService executionService,
        IExportService exportService,
        IControlFactory controlFactory,
        IVisualizerFactory visualizerFactory,
        ILogger<MainViewModel> logger)
    {
        _scriptManager = scriptManager;
        _executionService = executionService;
        _exportService = exportService;
        _controlFactory = controlFactory;
        _visualizerFactory = visualizerFactory;
        _logger = logger;

        LoadScriptsCommand = new AsyncRelayCommand(LoadScriptsAsync);
        ExecuteCommand = new AsyncRelayCommand(ExecuteScriptAsync, CanExecuteScript);
        ExportCommand = new AsyncRelayCommand(ExportResultsAsync, CanExportResults);
        CopySqlCommand = new RelayCommand(CopySqlToClipboard);
        ClearResultsCommand = new RelayCommand(ClearResults);
        SaveParametersCommand = new RelayCommand(SaveParameters);
        LoadParametersCommand = new RelayCommand(LoadParameters);

        // Подписка на события
        _scriptManager.ScriptChanged += OnScriptChanged;
        _scriptManager.ScriptsReloaded += OnScriptsReloaded;
    }

    private async Task LoadScriptsAsync()
    {
        try
        {
            IsBusy = true;
            StatusMessage = "Загрузка скриптов...";

            var scripts = await _scriptManager.LoadScriptsAsync();
            _scripts.Clear();

            foreach (var script in scripts)
            {
                _scripts.Add(script);
            }

            CategorizeScripts();
            StatusMessage = $"Загружено {_scripts.Count} скриптов";
        }
        catch (Exception ex)
        {
            _logger.LogError(ex, "Error loading scripts");
            StatusMessage = $"Ошибка загрузки: {ex.Message}";
        }
        finally
        {
            IsBusy = false;
        }
    }

    private void CategorizeScripts()
    {
        _scriptCategories.Clear();

        var categories = _scripts
            .GroupBy(s => s.Category ?? "Без категории")
            .OrderBy(g => g.Key);

        foreach (var category in categories)
        {
            var scriptCategory = new ScriptCategory
            {
                Name = category.Key,
                Scripts = new ObservableCollection<ScriptMetadata>(category.OrderBy(s => s.FileName))
            };

            _scriptCategories.Add(scriptCategory);
        }
    }

    private void FilterScripts()
    {
        if (string.IsNullOrWhiteSpace(SearchText))
        {
            // Показать все скрипты
            foreach (var category in _scriptCategories)
            {
                foreach (var script in category.Scripts)
                {
                    script.IsVisible = true;
                }
            }
        }
        else
        {
            var searchLower = SearchText.ToLower();

            foreach (var category in _scriptCategories)
            {
                foreach (var script in category.Scripts)
                {
                    script.IsVisible =
                        script.FileName.ToLower().Contains(searchLower) ||
                        script.Description?.ToLower().Contains(searchLower) == true ||
                        script.Tags.Any(t => t.ToLower().Contains(searchLower));
                }
            }
        }
    }

    private void OnSelectedScriptChanged()
    {
        Parameters.Clear();

        if (_selectedScript == null) return;

        // Создание ViewModel для каждого параметра
        foreach (var param in _selectedScript.Parameters.OrderBy(p => p.Order))
        {
            var paramVm = new ParameterViewModel(param, _controlFactory);
            paramVm.ValueChanged += OnParameterValueChanged;
            Parameters.Add(paramVm);
        }

        // Восстановление сохраненных значений
        LoadSavedParameters();
    }

    private void OnParameterValueChanged(object sender, EventArgs e)
    {
        ExecuteCommand.NotifyCanExecuteChanged();

        // Обновление зависимых параметров
        if (sender is ParameterViewModel changedParam)
        {
            UpdateDependentParameters(changedParam);
        }
    }

    private void UpdateDependentParameters(ParameterViewModel changedParam)
    {
        foreach (var paramVm in Parameters)
        {
            if (paramVm.Parameter.DependsOn == changedParam.Parameter.Name)
            {
                paramVm.UpdateDependencies(GetCurrentParameterValues());
            }
        }
    }

    private Dictionary<string, object> GetCurrentParameterValues()
    {
        return Parameters.ToDictionary(
            p => p.Parameter.Name,
            p => p.Value ?? p.Parameter.DefaultValue);
    }

    private bool CanExecuteScript()
    {
        if (_selectedScript == null) return false;

        // Проверка обязательных параметров
        foreach (var paramVm in Parameters)
        {
            if (paramVm.Parameter.IsRequired &&
                (paramVm.Value == null || string.IsNullOrWhiteSpace(paramVm.Value.ToString())))
            {
                return false;
            }
        }

        return true;
    }

    private async Task ExecuteScriptAsync()
    {
        try
        {
            IsBusy = true;
            StatusMessage = "Выполнение скрипта...";

            var parameters = GetCurrentParameterValues();

            var result = await _executionService.ExecuteAsync(_selectedScript, parameters);

            // Добавление в историю
            var historyItem = new ExecutionHistoryItem
            {
                ScriptId = _selectedScript.Id,
                ScriptName = _selectedScript.FileName,
                ExecutionTime = DateTime.Now,
                Duration = result.ExecutionTime,
                Success = result.IsSuccess,
                Parameters = new Dictionary<string, object>(parameters),
                RowCount = result.RowCount,
                ErrorMessage = result.ErrorMessage,
                ExecutedSql = result.ExecutedSql
            };

            _history.Insert(0, historyItem);

            // Очистка старых записей истории
            while (_history.Count > 1000)
            {
                _history.RemoveAt(_history.Count - 1);
            }

            if (result.IsSuccess)
            {
                CreateResultTabs(result);
                StatusMessage = $"Выполнено за {result.ExecutionTime.TotalSeconds:F2} сек. Получено строк: {result.RowCount}";
            }
            else
            {
                StatusMessage = $"Ошибка: {result.ErrorMessage}";
                ShowErrorDialog(result.ErrorMessage);
            }

            // Сохранение параметров
            SaveParameters();
        }
        catch (Exception ex)
        {
            _logger.LogError(ex, "Error executing script");
            StatusMessage = $"Ошибка: {ex.Message}";
            ShowErrorDialog(ex.Message);
        }
        finally
        {
            IsBusy = false;
        }
    }

    private void CreateResultTabs(ExecutionResult result)
    {
        // Удаляем старые вкладки
        ResultTabs.Clear();

        for (int i = 0; i < result.Data.Tables.Count; i++)
        {
            var table = result.Data.Tables[i];
            var outputDef = i < _selectedScript.Outputs.Count
                ? _selectedScript.Outputs[i]
                : CreateDefaultOutputDefinition(table, i);

            var visualizer = _visualizerFactory.GetVisualizer(outputDef.Type);
            var content = visualizer.Visualize(table, outputDef);

            var tabVm = new ResultTabViewModel
            {
                Title = outputDef.Description,
                Content = content,
                DataTable = table,
                OutputDefinition = outputDef,
                CanExport = true,
                CanCopy = true
            };

            ResultTabs.Add(tabVm);
        }

        if (ResultTabs.Any())
        {
            SelectedResultTab = ResultTabs[0];
        }
    }

    private OutputDefinition CreateDefaultOutputDefinition(DataTable table, int index)
    {
        return new OutputDefinition
        {
            Type = OutputType.Table,
            Description = $"Результат {index + 1}",
            DataTableName = table.TableName
        };
    }

    private bool CanExportResults()
    {
        return SelectedResultTab != null &&
               SelectedResultTab.DataTable != null &&
               SelectedResultTab.DataTable.Rows.Count > 0;
    }

    private async Task ExportResultsAsync()
    {
        if (SelectedResultTab?.DataTable == null) return;

        try
        {
            var savePicker = new FileSavePicker();
            savePicker.SuggestedStartLocation = PickerLocationId.DocumentsLibrary;
            savePicker.FileTypeChoices.Add("Excel файл", new List<string> { ".xlsx" });
            savePicker.FileTypeChoices.Add("CSV файл", new List<string> { ".csv" });
            savePicker.FileTypeChoices.Add("JSON файл", new List<string> { ".json" });
            savePicker.SuggestedFileName = $"{_selectedScript.FileName}_{DateTime.Now:yyyyMMdd_HHmmss}";

            var file = await savePicker.PickSaveFileAsync();
            if (file != null)
            {
                var options = new ExportOptions
                {
                    Format = Path.GetExtension(file.Path).TrimStart('.').ToUpper(),
                    IncludeHeaders = true,
                    AutoFilter = true
                };

                await _exportService.ExportAsync(SelectedResultTab.DataTable, file.Path, options);

                StatusMessage = $"Экспортировано в {file.Path}";
            }
        }
        catch (Exception ex)
        {
            _logger.LogError(ex, "Error exporting results");
            StatusMessage = $"Ошибка экспорта: {ex.Message}";
        }
    }

    private void CopySqlToClipboard()
    {
        if (_selectedScript == null) return;

        var parameters = GetCurrentParameterValues();
        var sql = FormatSqlWithParameters(_selectedScript.ProcessedSql, parameters);

        var package = new DataPackage();
        package.SetText(sql);
        Clipboard.SetContent(package);

        StatusMessage = "SQL скопирован в буфер обмена";
    }

    private string FormatSqlWithParameters(string sql, Dictionary<string, object> parameters)
    {
        var result = new StringBuilder(sql);

        foreach (var param in parameters)
        {
            var paramName = $"@{param.Key}";
            var paramValue = FormatParameterForDisplay(param.Value);

            result = result.Replace(paramName, paramValue);
        }

        return result.ToString();
    }

    private string FormatParameterForDisplay(object value)
    {
        if (value == null) return "NULL";

        return value switch
        {
            string str => $"N'{str.Replace("'", "''")}'",
            DateTime dt => $"'{dt:yyyy-MM-dd HH:mm:ss}'",
            bool b => b ? "1" : "0",
            _ => value.ToString()
        };
    }

    private void ClearResults()
    {
        ResultTabs.Clear();
        StatusMessage = "Результаты очищены";
    }

    private void SaveParameters()
    {
        if (_selectedScript == null) return;

        var parameters = GetCurrentParameterValues();
        var settings = ApplicationData.Current.LocalSettings;

        var dict = new Dictionary<string, object>();
        foreach (var param in parameters)
        {
            dict[param.Key] = param.Value;
        }

        var json = JsonSerializer.Serialize(dict);
        settings.Values[$"ScriptParams_{_selectedScript.Id}"] = json;

        StatusMessage = "Параметры сохранены";
    }

    private void LoadParameters()
    {
        if (_selectedScript == null) return;

        var settings = ApplicationData.Current.LocalSettings;
        if (settings.Values.TryGetValue($"ScriptParams_{_selectedScript.Id}", out var jsonObj))
        {
            try
            {
                var savedParams = JsonSerializer.Deserialize<Dictionary<string, object>>(jsonObj.ToString());

                foreach (var paramVm in Parameters)
                {
                    if (savedParams.TryGetValue(paramVm.Parameter.Name, out var value))
                    {
                        paramVm.Value = value;
                    }
                }

                StatusMessage = "Параметры загружены";
            }
            catch (Exception ex)
            {
                _logger.LogWarning(ex, "Error loading saved parameters");
            }
        }
    }

    private void ShowErrorDialog(string message)
    {
        // Реализация диалога ошибки
        // Можно использовать ContentDialog или другое UI решение
    }

    private void OnScriptChanged(object sender, ScriptChangedEventArgs e)
    {
        // Обновление UI при изменении скрипта
        DispatcherQueue.GetForCurrentThread().TryEnqueue(() =>
        {
            CategorizeScripts();

            if (e.ChangeType == ScriptChangeType.Deleted &&
                _selectedScript?.FullPath == e.FilePath)
            {
                SelectedScript = null;
            }
        });
    }

    private void OnScriptsReloaded(object sender, ScriptsReloadedEventArgs e)
    {
        DispatcherQueue.GetForCurrentThread().TryEnqueue(CategorizeScripts);
    }
}