using Prism.Commands;
using Prism.Mvvm;
using Prism.Regions;
using System;
using System.Collections.ObjectModel;
using System.Diagnostics;
using System.Windows;
using System.Windows.Media;
using System.Windows.Threading;
using TeamAAS.Core;
using TeamAAS.Models;
using TeamAAS.Localization;
using TeamAAS.Theme;

namespace TeamAAS.ViewModels
{
    public class MainWindowViewModel : TeamAAS.BindableBase
    {
        private readonly IRegionManager _regionManager;
        private DispatcherTimer _timer;

        public ObservableCollection<DeviceStatusItem> DeviceStatusItems { get; } = new ObservableCollection<DeviceStatusItem>();

        /// <summary>左侧导航（首页/产品/设置）</summary>
        public ObservableCollection<NavItem> LeftNavItems { get; } = new ObservableCollection<NavItem>();

        /// <summary>右侧导航（标定/统计/用户）</summary>
        public ObservableCollection<NavItem> RightNavItems { get; } = new ObservableCollection<NavItem>();

        private string _memoryUsage = "";
        public string MemoryUsage
        {
            get => _memoryUsage;
            set => SetProperty(ref _memoryUsage, value);
        }

        private string _currentTime = "";
        public string CurrentTime
        {
            get => _currentTime;
            set => SetProperty(ref _currentTime, value);
        }

        private string _currentView = "HomeView";
        public string CurrentView
        {
            get => _currentView;
            set => SetProperty(ref _currentView, value);
        }

        #region 主题与主色

        public bool IsDarkMode
        {
            get => string.Equals(App.SystemConfig?.Theme, "Dark", StringComparison.OrdinalIgnoreCase);
            set
            {
                if (IsDarkMode == value) return;

                App.SystemConfig.Theme = value ? "Dark" : "Light";
                ThemeManager.ApplyTheme(value, App.SystemConfig.AccentColor);
                App.SaveSystemConfig();

                RaisePropertyChanged(nameof(IsDarkMode));
                RaisePropertyChanged(nameof(ThemeIcon));
                RaisePropertyChanged(nameof(ThemeDisplayName));
            }
        }

        public string ThemeIcon => IsDarkMode ? "☀️" : "🌙";

        public string ThemeDisplayName => IsDarkMode ? "深色（点击切换）" : "浅色（点击切换）";

        public ObservableCollection<AccentColorOption> AccentColors { get; }
            = new ObservableCollection<AccentColorOption>();

        public Brush AccentBrush
        {
            get
            {
                try
                {
                    var color = (Color)ColorConverter.ConvertFromString(App.SystemConfig?.AccentColor);
                    // 规范化为主色不透明版本(配置里可能残留带 alpha 的历史值)
                    var brush = new SolidColorBrush(Color.FromRgb(color.R, color.G, color.B));
                    brush.Freeze();
                    return brush;
                }
                catch { return Brushes.DodgerBlue; }
            }
            set => ApplyAccent(value);
        }

        public DelegateCommand<string> NavigateCommand { get; }
        public DelegateCommand ToggleThemeCommand { get; }
        public DelegateCommand<string> SetAccentCommand { get; }

        public MainWindowViewModel(IRegionManager regionManager)
        {
            _regionManager = regionManager;
            NavigateCommand = new DelegateCommand<string>(Navigate);
            ToggleThemeCommand = new DelegateCommand(() => IsDarkMode = !IsDarkMode);
            SetAccentCommand = new DelegateCommand<string>(hex =>
            {
                if (string.IsNullOrWhiteSpace(hex)) return;
                App.SystemConfig.AccentColor = hex;
                // 主色系画刷与文字对比色由主题覆盖层派生重建（毫秒级生效）
                ThemeManager.UpdateAccent(hex);
                App.SaveSystemConfig();
                RaisePropertyChanged(nameof(AccentBrush));
            });

            InitAccentColors();

            ThemeManager.ThemeChanged += OnAppThemeChanged;

            InitNavItems();
        }

        private void InitAccentColors()
        {
            var presets = new[]
            {
                ("默认蓝", "#2D6CDF"),
                ("成功绿", "#4CAF50"),
                ("活力橙", "#FF9800"),
                ("警示红", "#F44336"),
                ("优雅紫", "#7B1FA2"),
                ("清新青", "#00BCD4"),
                ("少女粉", "#E91E63"),
                ("中性灰", "#607D8B"),
            };
            foreach (var (name, hex) in presets)
            {
                AccentColors.Add(new AccentColorOption
                {
                    Name = name,
                    Hex = hex,
                    Brush = new SolidColorBrush((Color)ColorConverter.ConvertFromString(hex))
                });
            }
        }

        private void ApplyAccent(Brush brush)
        {
            if (!(brush is SolidColorBrush sb)) return;

            // 规范化:只取 RGB、强制不透明。ColorPicker 样式重算时会回写带任意 alpha 的画刷
            // (实测出现过 A=0x0A 的 96% 透明色被存进配置,表现为主色"特别淡、朦了一层"),
            // 统一丢弃 alpha——色相保真,主色永远纯色。
            var color = Color.FromRgb(sb.Color.R, sb.Color.G, sb.Color.B);

            // 按 RGB 去重:同色不同 alpha 的回写(切主题时样式重算触发)完全静默忽略
            var current = TryParseAccentColor();
            if (current.HasValue &&
                current.Value.R == color.R && current.Value.G == color.G && current.Value.B == color.B)
            {
                return;
            }

            App.SystemConfig.AccentColor = color.ToString();
            // 主色系画刷与文字对比色由主题覆盖层派生重建（毫秒级生效，不碰合并字典）
            ThemeManager.UpdateAccent(color);
            App.SaveSystemConfig();
            RaisePropertyChanged(nameof(AccentBrush));
        }

        private static Color? TryParseAccentColor()
        {
            try
            {
                var hex = App.SystemConfig?.AccentColor;
                if (string.IsNullOrWhiteSpace(hex)) return null;
                return (Color)ColorConverter.ConvertFromString(hex);
            }
            catch { return null; }
        }

        private void OnAppThemeChanged()
        {
            RaisePropertyChanged(nameof(IsDarkMode));
            RaisePropertyChanged(nameof(ThemeIcon));
            RaisePropertyChanged(nameof(ThemeDisplayName));
            RaisePropertyChanged(nameof(AccentBrush));
        }

        #endregion

        public void OnLoaded()
        {
            Navigate("HomeView");
            StartTimer();
        }

        #region 导航

        private void InitNavItems()
        {
            // 图标沿用 Material Design Path（与旧 XAML 资源一致）
            AddNav(LeftNavItems, "首页", "HomeView",
                "M10,20V14H14V20H19V12H22L12,3L2,12H5V20H10Z");
            AddNav(LeftNavItems, "产品", "ProductView",
                "M12,2L2,7V17L12,22L22,17V7L12,2Z M12,2V12 M2,7L12,12L22,7");
            AddNav(LeftNavItems, "设置", "SettingView",
                "M19.14,12.94C19.18,12.64 19.2,12.33 19.2,12C19.2,11.68 19.18,11.36 19.13,11.06L21.16,9.48C21.34,9.34 21.39,9.07 21.27,8.87L19.35,5.55C19.23,5.33 18.96,5.25 18.73,5.33L16.38,6.28C15.88,5.89 15.35,5.56 14.76,5.32L14.4,2.81C14.36,2.57 14.16,2.4 13.92,2.4H10.08C9.83,2.4 9.63,2.57 9.59,2.81L9.24,5.32C8.65,5.56 8.11,5.89 7.62,6.28L5.27,5.33C5.04,5.25 4.77,5.33 4.65,5.55L2.73,8.87C2.61,9.07 2.66,9.34 2.84,9.48L4.87,11.06C4.82,11.36 4.8,11.68 4.8,12C4.8,12.33 4.82,12.64 4.87,12.94L2.84,14.52C2.66,14.66 2.61,14.93 2.73,15.13L4.65,18.45C4.77,18.67 5.04,18.75 5.27,18.67L7.62,17.72C8.11,18.11 8.65,18.44 9.24,18.68L9.6,21.19C9.64,21.43 9.84,21.6 10.08,21.6H13.92C14.17,21.6 14.37,21.43 14.41,21.19L14.76,18.68C15.35,18.44 15.89,18.11 16.38,17.72L18.73,18.67C18.96,18.75 19.23,18.67 19.35,18.45L21.27,15.13C21.39,14.93 21.34,14.66 21.16,14.52L19.14,12.94ZM12,15.6C10.02,15.6 8.4,13.98 8.4,12C8.4,10.02 10.02,8.4 12,8.4C13.98,8.4 15.6,10.02 15.6,12C15.6,13.98 13.98,15.6 12,15.6Z");

            AddNav(RightNavItems, "标定", "CalibrationView",
                "M14.06,9L15,9.94L5.92,19H5V18.08L14.06,9M17.66,3C17.41,3 17.15,3.1 16.96,3.29L15.13,5.12L18.88,8.87L20.71,7.04C21.1,6.65 21.1,6 20.71,5.63L18.37,3.29C18.17,3.09 17.92,3 17.66,3M14.06,6.19L3,17.25V21H6.75L17.81,9.94L14.06,6.19Z");
            AddNav(RightNavItems, "统计", "StatisticsView",
                "M3,3H21V21H3V3Z M7,17V11 M12,17V7 M17,17V13");
            AddNav(RightNavItems, "用户", "UserView",
                "M12,4A4,4 0 0,1 16,8A4,4 0 0,1 12,12A4,4 0 0,1 8,8A4,4 0 0,1 12,4M12,14C16.42,14 20,15.79 20,18V20H4V18C4,15.79 7.58,14 12,14Z");
        }

        private void AddNav(ObservableCollection<NavItem> collection, string title, string viewName, string iconData)
        {
            // Path.Data 在运行时不会自动把字符串转成 Geometry，
            // 必须在代码里 Geometry.Parse 成对象（并 Freeze 提升渲染性能/线程安全）
            var geometry = Geometry.Parse(iconData);
            geometry.Freeze();

            var item = new NavItem { Title = title, ViewName = viewName, IconData = geometry };
            item.SelectRequested += nav =>
            {
                if (CurrentView != nav.ViewName)
                    Navigate(nav.ViewName);
            };
            collection.Add(item);
        }

        private void Navigate(string viewName)
        {
            if (string.IsNullOrEmpty(viewName)) return;

            _regionManager.RequestNavigate("ContentRegion", viewName, r =>
            {
                if (r.Result != true)
                {
                    // 解包内部异常链，找到根因（Prism 只抛 ContainerResolutionException 外壳）
                    var root = r.Error;
                    var depth = 0;
                    while (root?.InnerException != null && depth++ < 10)
                        root = root.InnerException;
                    AppLogger.Error($"导航到 {viewName} 失败，内容区保持原页面 | 根因: {root?.Message}", r.Error, "Navigation");
                }
            });
            CurrentView = viewName;

            // 每次导航都同步选中状态（含首次启动：
            // 初始 CurrentView 与目标相同，不能依赖"是否变化"判断，否则首页不会被选中）
            SyncNavSelection();
        }

        private void SyncNavSelection()
        {
            foreach (var nav in LeftNavItems)
                nav.IsSelected = nav.ViewName == CurrentView;
            foreach (var nav in RightNavItems)
                nav.IsSelected = nav.ViewName == CurrentView;
        }

        #endregion

        #region 定时刷新

        private void StartTimer()
        {
            // Loaded 事件在 WPF 中可能触发多次，避免重复创建定时器导致刷新回调叠加。
            if (_timer != null)
                return;

            _timer = new DispatcherTimer { Interval = TimeSpan.FromSeconds(1) };
            _timer.Tick += OnTimerTick;
            _timer.Start();
        }

        private void OnTimerTick(object sender, EventArgs e)
        {
            RefreshDeviceStatuses();
            UpdateSystemInfo();
        }

        private void RefreshDeviceStatuses()
        {
            var statuses = CoreManager.GetAllDeviceStatuses();

            if (DeviceStatusItems.Count != statuses.Count)
            {
                DeviceStatusItems.Clear();
                foreach (var s in statuses)
                    DeviceStatusItems.Add(new DeviceStatusItem { Name = s.Name, Category = L10n.T(s.Category), IsConnected = s.IsConnected });
                return;
            }

            // 设备数量未变时也要同步名称/类别（用户在设备管理页改名后即时反映到状态栏）
            for (int i = 0; i < statuses.Count; i++)
            {
                DeviceStatusItems[i].Name = statuses[i].Name;
                DeviceStatusItems[i].Category = L10n.T(statuses[i].Category);
                DeviceStatusItems[i].IsConnected = statuses[i].IsConnected;
            }
        }

        private void UpdateSystemInfo()
        {
            var proc = Process.GetCurrentProcess();
            MemoryUsage = L10n.F("内存: {0} MB", proc.PrivateMemorySize64 / 1024 / 1024);
            CurrentTime = DateTime.Now.ToString("yyyy-MM-dd HH:mm:ss");
        }

        #endregion
    }

    /// <summary>
    /// 顶部导航项（数据驱动生成导航按钮，新增页面只需在 MainWindowViewModel.InitNavItems 加一行）
    /// </summary>
    public class NavItem : TeamAAS.BindableBase
    {
        public string Title { get; set; }
        public string ViewName { get; set; }

        /// <summary>图标 Geometry 对象（Path.Data 直接绑定，避免运行时字符串→Geometry 转换失败）</summary>
        public Geometry IconData { get; set; }

        private bool _isSelected;
        public bool IsSelected
        {
            get => _isSelected;
            set
            {
                if (SetProperty(ref _isSelected, value) && value)
                    SelectRequested?.Invoke(this);
            }
        }

        public event Action<NavItem> SelectRequested;
    }

    public class DeviceStatusItem : TeamAAS.BindableBase
    {
        private string _name;
        private string _category;
        private bool _isConnected;
        public string Name
        {
            get => _name;
            set => SetProperty(ref _name, value);
        }
        public string Category
        {
            get => _category;
            set => SetProperty(ref _category, value);
        }
        public bool IsConnected
        {
            get => _isConnected;
            set => SetProperty(ref _isConnected, value);
        }
    }
}