using System.Collections;
using System.Collections.ObjectModel;
using AutoMapper;
using CommunityToolkit.Mvvm.ComponentModel;
using CommunityToolkit.Mvvm.Input;
using DMS.Application.DTOs;
using DMS.Application.Interfaces;
using DMS.Core.Models;
using DMS.WPF.Interfaces;
using DMS.WPF.ViewModels.Items;
using Microsoft.Extensions.DependencyInjection;
using ObservableCollections;
using System.Linq;

namespace DMS.WPF.ViewModels;

partial class VariableHistoryViewModel : ViewModelBase, INavigatable
{
    private readonly IMapper _mapper;
    private readonly IDialogService _dialogService;
    private readonly IHistoryAppService _historyAppService;
    private readonly IWPFDataService _wpfDataService;
    private readonly IDataStorageService _dataStorageService;
    private readonly INotificationService _notificationService;

    /// <summary>
    /// 用于过滤变量的搜索文本
    /// </summary>
    [ObservableProperty]
    private string _searchText;

    /// <summary>
    /// 是否打开建议列表
    /// </summary>
    [ObservableProperty]
    private bool _isSuggestionListOpen;

    /// <summary>
    /// 建议的变量列表
    /// </summary>
    [ObservableProperty]
    private ObservableCollection<string> _suggestedVariables;

    /// <summary>
    /// 历史记录条数限制
    /// </summary>
    [ObservableProperty]
    private int? _historyLimit;

    /// <summary>
    /// 历史记录开始时间
    /// </summary>
    [ObservableProperty]
    private DateTime? _startTime;

    /// <summary>
    /// 历史记录结束时间
    /// </summary>
    [ObservableProperty]
    private DateTime? _endTime;

    /// <summary>
    /// 选中的变量历史记录
    /// </summary>
    [ObservableProperty]
    private VariableHistoryDto _selectedVariable;

    /// <summary>
    /// 变量历史记录列表
    /// </summary>
    public NotifyCollectionChangedSynchronizedViewList<VariableHistoryDto> VariableHistories { get; }

    private readonly ObservableList<VariableHistoryDto> _variableHistoryList;
    private readonly ISynchronizedView<VariableHistoryDto, VariableHistoryDto> _variableHistorySynchronizedView;

    /// <summary>
    /// 所有变量的缓存列表，用于搜索
    /// </summary>
    private List<VariableHistoryDto> _allVariableHistories;

    public VariableHistoryViewModel(IMapper mapper, IDialogService dialogService, IHistoryAppService historyAppService,
                                    IWPFDataService wpfDataService, IDataStorageService dataStorageService,
                                    INotificationService notificationService)
    {
        _mapper = mapper;
        _dialogService = dialogService;
        _historyAppService = historyAppService;
        _wpfDataService = wpfDataService;
        _dataStorageService = dataStorageService;
        _notificationService = notificationService;

        _variableHistoryList = new ObservableList<VariableHistoryDto>();
        _variableHistorySynchronizedView = _variableHistoryList.CreateView(v => v);
        VariableHistories = _variableHistorySynchronizedView.ToNotifyCollectionChanged();
        _allVariableHistories = new List<VariableHistoryDto>();
        _suggestedVariables = new ObservableCollection<string>();

        // 初始化默认值
        _historyLimit = 1000; // 默认限制1000条记录
        _startTime = null;
        _endTime = null;
        _selectedVariable = new VariableHistoryDto();
    }

    /// <summary>
    /// 加载所有变量的历史记录
    /// </summary>
    /// <param name="limit">返回记录的最大数量，null表示无限制</param>
    /// <param name="startTime">开始时间，null表示无限制</param>
    /// <param name="endTime">结束时间，null表示无限制</param>
    private async void LoadAllVariableHistories(int? limit = null, DateTime? startTime = null, DateTime? endTime = null)
    {
        try
        {
            _variableHistoryList.Clear();
            var allHistories = await _historyAppService.GetAllVariableHistoriesAsync(limit, startTime, endTime);
            _allVariableHistories = allHistories.ToList();
            _variableHistoryList.AddRange(_allVariableHistories);

            // 更新建议列表
            UpdateSuggestedVariables();
        }
        catch (Exception ex)
        {
            // 记录更详细的错误信息
            _notificationService.ShowError($"加载变量历史记录失败: {ex.Message}", ex);
        }
    }

    /// <summary>
    /// 更新建议的变量列表
    /// </summary>
    private void UpdateSuggestedVariables()
    {
        // 清空现有建议列表
        _suggestedVariables.Clear();

        if (!string.IsNullOrWhiteSpace(SearchText))
        {
            // 根据搜索文本过滤建议列表
            var filteredVariables = _dataStorageService.Variables
                                                       .Where(v =>
                                                                  v.Name?.Contains(
                                                                      SearchText, StringComparison.OrdinalIgnoreCase) ==
                                                                  true)
                                                       .Select(v => v.Name)
                                                       .Take(10)
                                                       .ToList();

            foreach (var variable in filteredVariables)
            {
                _suggestedVariables.Add(variable);
            }
        }
    }

    public async Task OnNavigatedToAsync(MenuItemViewModel menu)
    {
        // 加载所有变量的历史记录
        LoadAllVariableHistories(HistoryLimit, StartTime, EndTime);
    }

    /// <summary>
    /// 重新加载历史记录命令
    /// </summary>
    [RelayCommand]
    private void Reload()
    {
        LoadAllVariableHistories(HistoryLimit, StartTime, EndTime);
    }

    /// <summary>
    /// 更新建议列表命令
    /// </summary>
    [RelayCommand]
    private void UpdateSuggestions()
    {
        UpdateSuggestedVariables();
    }

    /// <summary>
    /// 当搜索文本改变时触发
    /// </summary>
    /// <param name="value"></param>
    partial void OnSearchTextChanged(string value)
    {
        // 添加调试信息
        System.Diagnostics.Debug.WriteLine($"OnSearchTextChanged called with value: '{value}'");
        
        // 更新建议列表
        UpdateSuggestedVariables();

        if (string.IsNullOrWhiteSpace(value))
        {
            // 如果搜索文本为空，显示所有历史记录
            _variableHistoryList.Clear();
            _variableHistoryList.AddRange(_allVariableHistories);
        }
        else
        {
            // 根据搜索文本过滤历史记录
            var filteredHistories = _allVariableHistories
                                    .Where(h =>
                                               h.VariableName?.Contains(
                                                   value, StringComparison.OrdinalIgnoreCase) == true)
                                    .ToList();

            _variableHistoryList.Clear();
            _variableHistoryList.AddRange(filteredHistories);
        }
    }

    /// <summary>
    /// 根据搜索文本过滤历史记录
    /// </summary>
    /// <param name="searchText"></param>
    private void FilterHistoriesBySearchText(string searchText)
    {
        if (string.IsNullOrWhiteSpace(searchText))
        {
            // 如果搜索文本为空，显示所有历史记录
            _variableHistoryList.Clear();
            _variableHistoryList.AddRange(_allVariableHistories);
        }
        else
        {
            // 根据搜索文本过滤历史记录
            var filteredHistories = _allVariableHistories
                                    .Where(h =>
                                               h.VariableName?.Contains(
                                                   searchText, StringComparison.OrdinalIgnoreCase) == true)
                                    .ToList();

            _variableHistoryList.Clear();
            _variableHistoryList.AddRange(filteredHistories);
        }
    }

    /// <summary>
    /// 重新加载历史记录，使用当前设置的限制和时间范围
    /// </summary>
    public void ReloadHistories()
    {
        LoadAllVariableHistories(HistoryLimit, StartTime, EndTime);
    }

    /// <summary>
    /// 根据变量ID加载历史记录
    /// </summary>
    /// <param name="variableId">变量ID</param>
    /// <param name="limit">返回记录的最大数量，null表示无限制</param>
    /// <param name="startTime">开始时间，null表示无限制</param>
    /// <param name="endTime">结束时间，null表示无限制</param>
    public async Task LoadVariableHistoriesAsync(int variableId, int? limit = null, DateTime? startTime = null,
                                                 DateTime? endTime = null)
    {
        try
        {
            _variableHistoryList.Clear();
            var histories = await _historyAppService.GetVariableHistoriesAsync(variableId, limit, startTime, endTime);
            _variableHistoryList.AddRange(histories);

            // 更新建议列表
            UpdateSuggestedVariables();
        }
        catch (Exception ex)
        {
            // 记录更详细的错误信息
            _notificationService.ShowError($"加载变量历史记录失败: {ex.Message}", ex);
        }
    }
}