using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Controls.Primitives;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;
 

namespace Muchinfo.WPF.Controls
{
    /// <summary>
    /// 按照步骤 1a 或 1b 操作，然后执行步骤 2 以在 XAML 文件中使用此自定义控件。
    ///
    /// 步骤 1a) 在当前项目中存在的 XAML 文件中使用该自定义控件。
    /// 将此 XmlNamespace 特性添加到要使用该特性的标记文件的根 
    /// 元素中: 
    ///
    ///     xmlns:MyNamespace="clr-namespace:Muchinfo.MTPClient.Account.Views"
    ///
    ///
    /// 步骤 1b) 在其他项目中存在的 XAML 文件中使用该自定义控件。
    /// 将此 XmlNamespace 特性添加到要使用该特性的标记文件的根 
    /// 元素中: 
    ///
    ///     xmlns:MyNamespace="clr-namespace:Muchinfo.MTPClient.Account.Views;assembly=Muchinfo.MTPClient.Account.Views"
    ///
    /// 您还需要添加一个从 XAML 文件所在的项目到此项目的项目引用，
    /// 并重新生成以避免编译错误: 
    ///
    ///     在解决方案资源管理器中右击目标项目，然后依次单击
    ///     “添加引用”->“项目”->[浏览查找并选择此项目]
    ///
    ///
    /// 步骤 2)
    /// 继续操作并在 XAML 文件中使用控件。
    ///
    ///     <MyNamespace:OrderTabControl/>
    ///
    /// </summary>
    
     // [TemplatePart(Name = "XscrollViewer", Type = typeof(ScrollViewer))]

      [TemplatePart(Name = "PART_HorizontalScrollBar", Type = typeof(ScrollBar))]
      [TemplatePart(Name = "PART_SelectedContentHost", Type = typeof(ContentPresenter))]
      [TemplatePart(Name = "Part_TabViewer", Type = typeof(ScrollViewer))]
    public class OrderTabControl : TabControl
    {


        static OrderTabControl()
        {
            DefaultStyleKeyProperty.OverrideMetadata(typeof(OrderTabControl), new FrameworkPropertyMetadata(typeof(OrderTabControl)));
        }


        public OrderTabControl()
        { 
            this.LayoutUpdated += OrderTabControl_LayoutUpdated;
        }

        void OrderTabControl_LayoutUpdated(object sender, EventArgs e)
        {
           // SetScrollBar();
        }
 
  
        private ScrollViewer scrollViewer = null;
        private ScrollBar scrollBar = null;
        private ContentPresenter presenter = null;
        private bool _isSelectedChange = false;

        public override void OnApplyTemplate()
        {
            base.OnApplyTemplate();
          //  scrollViewer = this.GetTemplateChild("XscrollViewer") as ScrollViewer;
            scrollBar = this.GetTemplateChild("PART_HorizontalScrollBar") as ScrollBar;
            scrollViewer = this.GetTemplateChild("Part_TabViewer") as ScrollViewer;
            if (scrollBar != null)
            {
                scrollBar.ValueChanged+=scrollBar_ValueChanged;
            }
        }

        /// <summary>
        /// 横向滚动条的值
        /// </summary>
        public double HSValue
        {
            get { return (double)GetValue(HSValueProperty); }
            set { SetValue(HSValueProperty, value); }
        }

        // Using a DependencyProperty as the backing store for HSValue.  This enables animation, styling, binding, etc...
        public static readonly DependencyProperty HSValueProperty =
            DependencyProperty.Register("HSValue", typeof(double), typeof(OrderTabControl), new PropertyMetadata(0d,HSValueChangecalback));

          
        /// <summary>
        /// 横向滚动条
        /// </summary>
        public double ViewportWidth
        {
            get { return (double)GetValue(ViewportWidthProperty); }
            set { SetValue(ViewportWidthProperty, value); }
        }

        // Using a DependencyProperty as the backing store for ViewportWidth.  This enables animation, styling, binding, etc...
        public static readonly DependencyProperty ViewportWidthProperty =
            DependencyProperty.Register("ViewportWidth", typeof(double), typeof(OrderTabControl), new PropertyMetadata(0d));




        public double ScrollableWidth
        {
            get { return (double)GetValue(ScrollableWidthProperty); }
            set { SetValue(ScrollableWidthProperty, value); }
        }

        // Using a DependencyProperty as the backing store for ScrollableWidth.  This enables animation, styling, binding, etc...
        public static readonly DependencyProperty ScrollableWidthProperty =
            DependencyProperty.Register("ScrollableWidth", typeof(double), typeof(OrderTabControl), new PropertyMetadata(0d));

        


        private static void HSValueChangecalback(DependencyObject d, DependencyPropertyChangedEventArgs e)
        {
            var oTabControl = d as OrderTabControl;
            if (oTabControl != null && oTabControl.scrollViewer!=null)
            {
                oTabControl.scrollViewer.ScrollToHorizontalOffset((double)e.NewValue);
            }
        }

        private void scrollBar_ValueChanged(object sender, RoutedPropertyChangedEventArgs<double> e)
        {
            if (scrollViewer != null)
            {
                scrollViewer.ScrollToHorizontalOffset((double)e.NewValue);
            }
        }
           
        protected override void OnRenderSizeChanged(SizeChangedInfo info)
        {
            base.OnRenderSizeChanged(info);
            //SetScrollBar();
        }

        /// <summary>
        /// 设置滚动条
        /// </summary>
        private void SetScrollBar()
        {
             
                var uielement = this.SelectedContent as UIElement;
                if (uielement != null)
                {
                    scrollViewer = FindVisualChild<ScrollViewer>(uielement);
               
                }
            
            if (scrollViewer != null && scrollBar != null)
            {
                //scrollBar.Value = scrollViewer.HorizontalOffset;
                //scrollBar.Maximum = scrollViewer.ScrollableWidth;
                //scrollBar.ViewportSize = scrollViewer.ViewportWidth;
                ViewportWidth = scrollViewer.ViewportWidth;
                ScrollableWidth = scrollViewer.ScrollableWidth;
                HSValue = scrollViewer.HorizontalOffset;
            }
        }


        /// <summary>
        /// 从父容器中查找指定类型的控件
        /// </summary>
        /// <typeparam name="T"></typeparam>
        /// <param name="parent"></param>
        /// <returns></returns>
        private  T FindVisualChild<T>(DependencyObject parent) where T : DependencyObject
        {
            if (parent == null) return null;
            for (int i = 0; i < VisualTreeHelper.GetChildrenCount(parent); i++)
            {
                var childObject = VisualTreeHelper.GetChild(parent, i);
                if (childObject == null) return null;
                var child = childObject as T;
                if (child == null)
                {
                    var childItem = FindVisualChild<T>(childObject);
                    if (childItem != null) return childItem;
                }
                return child;
            }
            return null;
        }

        /// <summary>
        /// 查找指定类型的父容器
        /// </summary>
        /// <typeparam name="T"></typeparam>
        /// <param name="child">The child.</param>
        /// <returns>``0.</returns>
        private static T FindVisualParent<T>(DependencyObject child) where T : DependencyObject
        {
            if (child == null) return null;
            var parentObject = VisualTreeHelper.GetParent(child);
            if (parentObject == null) return null;
            var parent = parentObject as T;
            return parent ?? FindVisualParent<T>(parentObject);
        }
    }
}