using System;
using System.ComponentModel;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Media.Animation;
using TeamAAS.FlowEngine.Execution;
using TeamAAS.ViewModels;

namespace TeamAAS.Views
{
    public partial class ProductView : UserControl
    {
        private const double ExpandedWidth = 280;
        private const double CollapsedWidth = 56;
        private const double AnimationMs = 250;

        private ProductViewModel _vm;

        public ProductView()
        {
            InitializeComponent();
            DataContext = new ProductViewModel();
            DataContextChanged += OnDataContextChanged;
            Loaded += OnLoaded;
            Unloaded += OnUnloaded;
        }

        private void OnLoaded(object sender, RoutedEventArgs e)
        {
            HookViewModel(DataContext as ProductViewModel);
            // 运行/停止状态变化 → 刷新"运行中锁定"遮罩与角标
            FlowRunner.Instance.RunStateChanged += OnRunStateChanged;
            // 切回产品页时立即按当前运行状态同步一次，避免在别处启停流程后画布锁定状态滞后
            _vm?.RefreshRunState();
        }

        private void OnUnloaded(object sender, RoutedEventArgs e)
        {
            FlowRunner.Instance.RunStateChanged -= OnRunStateChanged;
        }

        private void OnRunStateChanged()
        {
            _vm?.RefreshRunState();
        }

        private void OnDataContextChanged(object sender, DependencyPropertyChangedEventArgs e)
        {
            HookViewModel(e.NewValue as ProductViewModel);
        }

        private void HookViewModel(ProductViewModel vm)
        {
            if (_vm != null)
                _vm.PropertyChanged -= OnVmPropertyChanged;

            _vm = vm;

            if (_vm != null)
            {
                _vm.PropertyChanged += OnVmPropertyChanged;
                ApplySidebarState(_vm.IsSidebarCollapsed, animate: false);
            }
        }

        private void OnVmPropertyChanged(object sender, PropertyChangedEventArgs e)
        {
            if (e.PropertyName == nameof(ProductViewModel.IsSidebarCollapsed))
            {
                ApplySidebarState(_vm.IsSidebarCollapsed, animate: true);
            }
        }

        /// <summary>
        /// 产品列表右键菜单"属性"：直接走 code-behind 事件（Context 弹窗在 Popup 独立可视树中，
        /// MenuItem 的 Command 绑定无法可靠命中 ViewModel，故不经过绑定）。
        /// 右键哪个产品就编辑哪个产品（PlacementTarget 的 DataContext = 产品名）。
        /// </summary>
        private void ProductProperties_Click(object sender, RoutedEventArgs e)
        {
            var vm = DataContext as ProductViewModel;
            if (vm == null) return;

            string productName = null;
            if (sender is MenuItem mi
                && mi.Parent is ContextMenu cm
                && cm.PlacementTarget is FrameworkElement target)
            {
                productName = target.DataContext as string;
            }

            if (string.IsNullOrEmpty(productName)) return;
            vm.ShowProductProperties(productName);
        }

        /// <summary>产品列表右键菜单“全局变量”：编辑该产品的 Product 作用域变量(弹窗)。</summary>
        private void ProductGlobalVars_Click(object sender, RoutedEventArgs e)
        {
            var vm = DataContext as ProductViewModel;
            if (vm == null) return;

            string productName = null;
            if (sender is MenuItem mi
                && mi.Parent is ContextMenu cm
                && cm.PlacementTarget is FrameworkElement target)
            {
                productName = target.DataContext as string;
            }

            if (string.IsNullOrEmpty(productName)) return;
            vm.ShowProductGlobalVars(productName);
        }

        private void ApplySidebarState(bool collapsed, bool animate)
        {
            double targetWidth = collapsed ? CollapsedWidth : ExpandedWidth;

            if (animate)
            {
                var widthAnim = new DoubleAnimation(targetWidth, TimeSpan.FromMilliseconds(AnimationMs))
                {
                    EasingFunction = new CubicEase { EasingMode = EasingMode.EaseInOut }
                };
                SidebarPanel.BeginAnimation(FrameworkElement.WidthProperty, widthAnim);
            }
            else
            {
                SidebarPanel.Width = targetWidth;
            }

            if (collapsed)
            {
                if (animate)
                {
                    var fadeOut = new DoubleAnimation(1.0, 0.0, TimeSpan.FromMilliseconds(120));
                    fadeOut.Completed += (s, args) =>
                    {
                        SidebarExpanded.Visibility = Visibility.Collapsed;
                        SidebarCollapsed.Visibility = Visibility.Visible;
                        SidebarCollapsed.Opacity = 0;
                        var fadeIn = new DoubleAnimation(0.0, 1.0, TimeSpan.FromMilliseconds(130));
                        SidebarCollapsed.BeginAnimation(UIElement.OpacityProperty, fadeIn);
                    };
                    SidebarExpanded.BeginAnimation(UIElement.OpacityProperty, fadeOut);
                }
                else
                {
                    SidebarExpanded.Visibility = Visibility.Collapsed;
                    SidebarCollapsed.Visibility = Visibility.Visible;
                    SidebarCollapsed.Opacity = 1.0;
                }
            }
            else
            {
                if (animate)
                {
                    var fadeOut = new DoubleAnimation(1.0, 0.0, TimeSpan.FromMilliseconds(120));
                    fadeOut.Completed += (s, args) =>
                    {
                        SidebarCollapsed.Visibility = Visibility.Collapsed;
                        SidebarExpanded.Visibility = Visibility.Visible;
                        SidebarExpanded.Opacity = 0;
                        var fadeIn = new DoubleAnimation(0.0, 1.0, TimeSpan.FromMilliseconds(130));
                        SidebarExpanded.BeginAnimation(UIElement.OpacityProperty, fadeIn);
                    };
                    SidebarCollapsed.BeginAnimation(UIElement.OpacityProperty, fadeOut);
                }
                else
                {
                    SidebarCollapsed.Visibility = Visibility.Collapsed;
                    SidebarExpanded.Visibility = Visibility.Visible;
                    SidebarExpanded.Opacity = 1.0;
                }
            }
        }
    }
}