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.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 ResourceDictionary genericResourceDictionary;
        public LabelListControl() {
            this.DefaultStyleKey = typeof(LabelListControl);
            var uri = new Uri("ms-appx:///Controls/LabelListControl.xaml");
            genericResourceDictionary = new ResourceDictionary();
            Application.LoadComponent(genericResourceDictionary, uri);
        }
        /// <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)");
        }

        /// <summary>
        /// 当ItemsSource改变时，绘制标签，注册动画
        /// </summary>
        private void 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.Content = label.tag;
                b.Background = new SolidColorBrush(label.color);
                b.SetValue(Canvas.LeftProperty, expanded_position);
                b.Style = (Style)genericResourceDictionary["LabelButtonStyle"];
                b.Click += B_Click;
                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);
        }
        /// <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) {
            Button b = sender as Button;
            Debug.WriteLine(b.Content);
        }
        /// <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;
            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) {
            _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) {
            _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();
        }
    }
}