using FileManager_UWP.Model;
using System;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.Diagnostics;
using System.Linq;
using System.Runtime.InteropServices.WindowsRuntime;
using Windows.Foundation;
using Windows.UI.Xaml;
using Windows.UI.Xaml.Controls;
using Windows.UI.Xaml.Data;
using Windows.UI.Xaml.Documents;
using Windows.UI.Xaml.Input;
using Windows.UI.Xaml.Markup;
using Windows.UI.Xaml.Media;
using Windows.UI.Xaml.Media.Animation;

// The Templated Control item template is documented at https://go.microsoft.com/fwlink/?LinkId=234235

namespace FileManager_UWP.Controls {
    /// <summary>
    /// 一个可以自动折叠的标签菜单
    /// </summary>
    public class LabelListControl: ItemsControl {

        //private int _collpse_distance = 22;
        //private List<int> _expanded_position = new List<int>();
        private Storyboard _collpse_story_board = new Storyboard();
        private Storyboard _expand_story_board = new Storyboard();
        private Duration _animate_during = new Duration(TimeSpan.FromMilliseconds(200));
        private Canvas labelListCanvas;
        private bool _adding_new_label = false;
        private bool _hovering = false, _draging = false;


        private ResourceDictionary genericResourceDictionary;
        public LabelListControl() {
            this.DefaultStyleKey = typeof(LabelListControl);
            var uri = new Uri("ms-appx:///Controls/LabelListControl.xaml");
            genericResourceDictionary = new ResourceDictionary();
            Application.LoadComponent(genericResourceDictionary, uri);
            AllowDrop = true;
        }
        /// <summary>
        /// 监听ItemSource改变
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void ItemsSource_CollectionChanged(object sender,
            System.Collections.Specialized.NotifyCollectionChangedEventArgs e) {
            update();
        }

        private void SetElasticAnimate(Button b, int expanded_position) {
            DoubleAnimation expand_animate = new DoubleAnimation();
            expand_animate.From = null; // labelListCanvas.Children.Count * 22;
            expand_animate.To = expanded_position;
            expand_animate.Duration = _animate_during;
            //expand_animate.Completed += Animate_Completed;
            _expand_story_board.Children.Add(expand_animate);
            Storyboard.SetTarget(expand_animate, b);
            Storyboard.SetTargetProperty(expand_animate, "(Canvas.Left)");

            DoubleAnimation collpse_animate = new DoubleAnimation();
            collpse_animate.From = null; // expanded_position;
            collpse_animate.To = labelListCanvas.Children.Count * 20;
            collpse_animate.Duration = _animate_during;
            //collpse_animate.Completed += Animate_Completed;
            _collpse_story_board.Children.Add(collpse_animate);
            Storyboard.SetTarget(collpse_animate, b);
            Storyboard.SetTargetProperty(collpse_animate, "(Canvas.Left)");
        }

        private DependencyProperty LabelProperty = DependencyProperty.Register(
            "LabelItem", typeof(LabelItem), typeof(Button), null);

        /// <summary>
        /// 当ItemsSource改变时，绘制标签，注册动画
        /// </summary>
        private void update() {
            Debug.WriteLine("ObservableCollection update");
            var itemsSource = ItemsSource as ObservableCollection<LabelItem>;

            labelListCanvas.Children.Clear();
            _collpse_story_board.Stop();
            _collpse_story_board.Children.Clear();
            _expand_story_board.Stop();
            _expand_story_board.Children.Clear();
            int expanded_position = 0;
            foreach (LabelItem label in itemsSource) {
                Button b = new Button();
                b.SetValue(LabelProperty, label);
                b.Content = label.tag;
                b.Background = new SolidColorBrush(label.color);
                b.SetValue(Canvas.LeftProperty, expanded_position);
                b.Style = (Style)genericResourceDictionary["LabelButtonStyle"];
                b.Click += B_Click;
                //b.AddHandler(PointerPressedEvent, new PointerEventHandler(B_PointerPressed), true);
                //b.AddHandler(PointerReleasedEvent, new PointerEventHandler(B_PointerReleased), true);
                InitManipulationTransforms(b);
                SetElasticAnimate(b, expanded_position);
                expanded_position += label.tag.Count() * 14 + 15;
                labelListCanvas.Children.Add(b);
            }
            Button add_button = new Button();
            SetElasticAnimate(add_button, expanded_position);
            add_button.Content = "+";
            add_button.SetValue(Canvas.LeftProperty, expanded_position);
            add_button.Style = (Style)genericResourceDictionary["LabelButtonStyle"];
            add_button.Click += Add_Click;
            DoubleAnimation appear_animate = new DoubleAnimation {
                To = 100,
                Duration = _animate_during
            };
            appear_animate.Completed += Animate_Completed;
            _expand_story_board.Children.Add(appear_animate);
            Storyboard.SetTarget(appear_animate, add_button);
            Storyboard.SetTargetProperty(appear_animate, "Opacity");
            DoubleAnimation disappear_animate = new DoubleAnimation {
                Duration = _animate_during
            };
            // 如果没有标签，则+不自动隐藏
            if (itemsSource.Count > 0)
                disappear_animate.To = 0;
            else
                disappear_animate.To = 100;
            disappear_animate.Completed += Animate_Completed;
            _collpse_story_board.Children.Add(disappear_animate);
            Storyboard.SetTarget(disappear_animate, add_button);
            Storyboard.SetTargetProperty(disappear_animate, "Opacity");

            labelListCanvas.Children.Add(add_button);
            measure();
            LabelListCanvas_PointerExited(null, null);
        }

        //private bool _pressing_label = false;
        //private void B_PointerPressed(object sender, PointerRoutedEventArgs e) {
        //    Debug.WriteLine("label pressed");
        //    _pressing_label = true;
        //}

        //private void B_PointerReleased(object sender, PointerRoutedEventArgs e) {
        //    Debug.WriteLine("label release");
        //    _pressing_label = false;
        //}

        private void B_ManipulationDelta(object sender, ManipulationDeltaRoutedEventArgs e) {
            TransformGroup transforms = (sender as Button).RenderTransform as TransformGroup;
            MatrixTransform previousTransform = transforms.Children[0] as MatrixTransform;
            CompositeTransform deltaTransform = transforms.Children[1] as CompositeTransform;
            previousTransform.Matrix = transforms.Value;

            // Get center point for rotation
            Point center = previousTransform.TransformPoint(new Point(e.Position.X, e.Position.Y));
            deltaTransform.CenterX = center.X;
            deltaTransform.CenterY = center.Y;

            // Look at the Delta property of the ManipulationDeltaRoutedEventArgs to retrieve
            // the rotation, scale, X, and Y changes
            deltaTransform.Rotation = e.Delta.Rotation;
            deltaTransform.TranslateX = e.Delta.Translation.X;
            deltaTransform.TranslateY = e.Delta.Translation.Y;
        }

        private void InitManipulationTransforms(Button b) {
            var transforms = new TransformGroup();
            var previousTransform = new MatrixTransform();
            previousTransform.Matrix = Matrix.Identity;
            var deltaTransform = new CompositeTransform();
            transforms.Children.Add(previousTransform);
            transforms.Children.Add(deltaTransform);

            b.RenderTransform = transforms;
            b.ManipulationMode = ManipulationModes.TranslateX | ManipulationModes.TranslateY;
            b.ManipulationDelta += B_ManipulationDelta;
            b.ManipulationStarted += B_ManipulationStarted;
            b.ManipulationCompleted += B_ManipulationCompleted;
        }

        private Point _origin;
        private void B_ManipulationCompleted(object sender, ManipulationCompletedRoutedEventArgs e) {
            Debug.WriteLine("Manipulation finish");
            _draging = false;
            ObservableCollection<LabelItem> itemsSource = ItemsSource as ObservableCollection<LabelItem>;
            itemsSource.Remove((sender as Button).GetValue(LabelProperty) as LabelItem);
            update();
        }

        private void B_ManipulationStarted(object sender, ManipulationStartedRoutedEventArgs e) {
            Debug.WriteLine("Manipulation start");
            _origin = e.Position;
            _draging = true;
        }

        private void B_DragLeave(object sender, DragEventArgs e) {
            var itemsSource = ItemsSource as ObservableCollection<LabelItem>;
            Button b = sender as Button;
            var tag = b.Content as string;
            Debug.WriteLine("Drag Leave " + tag);
            int index = itemsSource.ToList().FindIndex(x => x.tag == tag);
            itemsSource.RemoveAt(index);
        }

        /// <summary>
        /// 点击标签
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void B_Click(object sender, RoutedEventArgs e) {
            Button b = sender as Button;
            Debug.WriteLine(b.Content);
        }
        /// <summary>
        /// 点击新建标签
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void Add_Click(object sender, RoutedEventArgs e) {
            Debug.WriteLine("Click Add Label");
            Button b = sender as Button;
            TextBox textBox = new TextBox();
            textBox.Height = b.ActualHeight;
            textBox.FontSize = b.FontSize;
            textBox.BorderThickness = new Thickness(0);
            textBox.Padding = new Thickness(4, 4, 4, 4);
            textBox.Margin = new Thickness(0, 0, 0, 0);
            textBox.GotFocus += TextBox_GotFocus;
            textBox.LostFocus += TextBox_LostFocus;
            b.Content = textBox;
        }

        private void TextBox_LostFocus(object sender, RoutedEventArgs e) {
            _adding_new_label = false;
            TextBox tb = sender as TextBox;
            if (tb.Text.Count() != 0)
                (ItemsSource as ObservableCollection<LabelItem>).Add(new LabelItem(tb.Text));
            if (!_hovering)
                LabelListCanvas_PointerExited(null, null);
        }

        private void TextBox_GotFocus(object sender, RoutedEventArgs e) {
            _adding_new_label = true;
        }

        /// <summary>
        /// 动画完成
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void Animate_Completed(object sender, object e) {
            measure();
        }
        /// <summary>
        /// 计算控件尺寸
        /// </summary>
        private void measure() {
            Button lb = labelListCanvas.Children.Last() as Button;
            lb.Content = "+";
            labelListCanvas.Height = lb.ActualHeight;
            double left = (double)lb.GetValue(Canvas.LeftProperty);
            labelListCanvas.Width = left + lb.ActualWidth;
        }
        /// <summary>
        /// 鼠标离开
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void LabelListCanvas_PointerExited(object sender, PointerRoutedEventArgs e) {
            _hovering = false;
            // 正在输入新标签时不折叠
            if (!_adding_new_label && !_draging) {
                _collpse_story_board.Begin();
                for (int i = 0; i < labelListCanvas.Children.Count - 2; i++) {
                    Button b = labelListCanvas.Children[i] as Button;
                    b.Content = string.Format("{0}...", (b.Content as string)[0]);
                }
            }
        }
        /// <summary>
        /// 鼠标进入
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void LabelListCanvas_PointerEntered(object sender, PointerRoutedEventArgs e) {
            _hovering = true;
            if (!_adding_new_label && !_draging) {
                _expand_story_board.Begin();
                var labels = ItemsSource as ObservableCollection<LabelItem>;
                for (int i = 0; i < labels.Count - 1; i++) {
                    Button b = labelListCanvas.Children[i] as Button;
                    b.Content = labels[i].tag;
                }
            }
        }

        /// <summary>
        /// 初始化控件
        /// </summary>
        private void init() {
            var itemsSource = ItemsSource as ObservableCollection<LabelItem>;
            itemsSource.CollectionChanged += ItemsSource_CollectionChanged;
            Button labelListButton = (Button)GetTemplateChild("LabelListPresenter");
            labelListButton.PointerEntered += LabelListCanvas_PointerEntered;
            labelListButton.PointerExited += LabelListCanvas_PointerExited;
            labelListCanvas = (Canvas)GetTemplateChild("LabelListCanvas");

            //TextBlock textBlock = (TextBlock)GetTemplateChild("LabelTextBlock");
            //textBlock.Text = "测试自定义控件\nINIT";
        }

        /// <summary>
        /// 该Control被加载时调用
        /// </summary>
        protected override void OnApplyTemplate() {
            init();
            update();
        }
    }
}