using System;
using System.Collections;
using System.Collections.Generic;
using System.ComponentModel;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace SigmaDrawerStyle
{
    /// <summary>
    /// 属性排序类
    /// </summary>
    /// <seealso cref="System.ComponentModel.ExpandableObjectConverter" />
    public class PropertySorter : ExpandableObjectConverter
    {
        #region Methods
        /// <inheritdoc/>
        public override bool GetPropertiesSupported(ITypeDescriptorContext context)
        {
            return true;
        }
        public static Dictionary<Type, PropertyDescriptorCollection> GlobalPropertyDescriptor = new Dictionary<Type, PropertyDescriptorCollection>();
        /// <inheritdoc/>
        public override PropertyDescriptorCollection GetProperties(ITypeDescriptorContext context, object value, Attribute[] attributes)
        {
            Type typeObj = value.GetType();
            if (GlobalPropertyDescriptor.TryGetValue(typeObj, out PropertyDescriptorCollection properties))
            {
                return properties;
            }
            // 原始属性
            PropertyDescriptorCollection pdc = TypeDescriptor.GetProperties(value, attributes);
            List<PropertyOrderPair> orderedProperties = new List<PropertyOrderPair>();

            List<string> lstOriginCategory = new List<string>();
            List<string> lstCategoryTab = new List<string>();
            List<string> lstCategoryNoTab = new List<string>();

            foreach (PropertyDescriptor pd in pdc)
            {
                Attribute attribute = pd.Attributes[typeof(PropertyOrderAttribute)];
                string strCategory = pd.Category;
                if (attribute != null)
                {
                    PropertyOrderAttribute poa = (PropertyOrderAttribute)attribute;
                    orderedProperties.Add(new PropertyOrderPair(pd.Name, poa.Order, strCategory));
                }
                else
                {
                    // 没有序号的设置序号为 0
                    orderedProperties.Add(new PropertyOrderPair(pd.Name, 0, strCategory));
                }

                if (!lstOriginCategory.Contains(strCategory))
                {
                    lstOriginCategory.Add(strCategory);
                    if (strCategory.IndexOf('\t') >= 0)
                    {
                        lstCategoryTab.Add(strCategory);
                    }
                    else
                    {
                        lstCategoryNoTab.Add(strCategory);
                    }
                }
            }
            List<string> lstCategoryTabFinal = new List<string>();
            List<string> lstCategoryNoTabFinal = new List<string>();
            if (lstCategoryNoTab.Count > 1)
            {
                //char chNull = (char)0x0009;
                char chNull = '\u200B';
                lstCategoryTab.Sort();
                for (int i = 0; i < lstCategoryTab.Count; i++)
                {
                    string strCategory = lstCategoryTab[i];
                    strCategory = strCategory.Trim('\t');

                    strCategory = strCategory.PadLeft(strCategory.Length + lstOriginCategory.Count - i - 1, chNull);
                    lstCategoryTabFinal.Add(strCategory);
                }
                for (int i = 0; i < lstCategoryNoTab.Count; i++)
                {
                    string strCategory = lstCategoryNoTab[i];
                    strCategory = strCategory.PadLeft(strCategory.Length + lstOriginCategory.Count - lstCategoryTab.Count - i - 1, chNull);
                    lstCategoryNoTabFinal.Add(strCategory);
                }
            }

            List<PropertyDescriptor> finalList = new List<PropertyDescriptor>();
            foreach (PropertyDescriptor pd in pdc)
            {
                string strCagegory = pd.Category;
                if (lstCategoryNoTab.Count > 1)
                {
                    int nIndex = lstCategoryTab.IndexOf(strCagegory);
                    if (nIndex >= 0)
                    {
                        strCagegory = lstCategoryTabFinal[nIndex];
                    }
                    else
                    {
                        nIndex = lstCategoryNoTab.IndexOf(strCagegory);
                        if (nIndex >= 0)
                        {
                            strCagegory = lstCategoryNoTabFinal[nIndex];
                        }
                    }
                }

                var attrs = new Attribute[pd.Attributes.Count];
                pd.Attributes.CopyTo(attrs, 0);

                // 更新CategoryAttribute
                for (int j = 0; j < attrs.Length; j++)
                {
                    if (attrs[j] is CategoryAttribute)
                    {
                        attrs[j] = new CategoryAttribute(strCagegory);
                        break;
                    }
                }

                finalList.Add(TypeDescriptor.CreateProperty(
                    pd.ComponentType,
                    pd,
                    attrs));
            }

            // 重新设置类别属性
            orderedProperties.Sort();
            int nPropertyCount = orderedProperties.Count;
            string[] saOrderNames = new string[nPropertyCount];
            for (int i = 0; i < nPropertyCount; i++)
            {
                saOrderNames[i] = orderedProperties[i].Name;
            }
            PropertyDescriptorCollection result = new PropertyDescriptorCollection(finalList.ToArray(), true).Sort(saOrderNames);
            GlobalPropertyDescriptor.Add(typeObj, result);
            return result;
        }
        #endregion
    }

    #region Helper Class - PropertyOrderAttribute
    [AttributeUsage(AttributeTargets.Property)]
    public class PropertyOrderAttribute : Attribute
    {
        //
        // Simple attribute to allow the order of a property to be specified
        //
        private int _order;
        /// <summary>
        /// Initializes a new instance of the <see cref="PropertyOrderAttribute"/> class.
        /// </summary>
        /// <param name="order"></param>
        public PropertyOrderAttribute(int order)
        {
            _order = order;
        }

        public int Order
        {
            get
            {
                return _order;
            }
        }
    }
    #endregion

    #region Helper Class - PropertyOrderPair
    public class PropertyOrderPair : IComparable
    {
        private int _order;
        private string _name;
        public string Category { get; set; }
        public string Name
        {
            get
            {
                return _name;
            }
        }

        /// <summary>
        /// Initializes a new instance of the <see cref="PropertyOrderPair"/> class.
        /// </summary>
        /// <param name="name">名称</param>
        /// <param name="order">顺序号</param>
        public PropertyOrderPair(string name, int order)
        {
            _order = order;
            _name = name;
        }
        /// <summary>
        /// Initializes a new instance of the <see cref="PropertyOrderPair"/> class.
        /// </summary>
        /// <param name="name">名称.</param>
        /// <param name="order">序号.</param>
        /// <param name="category">分类.</param>
        public PropertyOrderPair(string name, int order, string category)
            : this(name, order)
        {
            this.Category = category;
        }

        public int CompareTo(object obj)
        {
            //
            // Sort the pair objects by ordering by order value
            // Equal values get the same rank
            //
            int otherOrder = ((PropertyOrderPair)obj)._order;
            if (otherOrder == _order)
            {
                //
                // If order not specified, sort by name
                //
                string otherName = ((PropertyOrderPair)obj)._name;
                return string.Compare(_name, otherName);
            }
            else if (otherOrder > _order)
            {
                return -1;
            }
            return 1;
        }
    }
    #endregion
}