using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.ComponentModel.DataAnnotations;
using System.Linq;
using System.Reflection;
using System.Web;

namespace Helper
{
    /// <summary>
    /// This classs contain property releted method
    /// </summary>
    public static class DisplayNameHelper
    {
        /// <summary>
        /// This mehtod is used for get display name of class object property
        /// </summary>
        /// <param name="obj">Represent object of object class contain proerties</param>
        /// <param name="propertyName">Represent name of the property</param>
        /// <returns></returns>
        public static string GetDisplayName(object obj, string propertyName)
        {
            if (obj == null) return null;
            return GetDisplayName(obj.GetType(), propertyName);

        }

        /// <summary>
        /// This method is used for returns value of display name.
        /// </summary>
        /// <param name="type">Type of the property</param>
        /// <param name="propertyName">Represent name of the property</param>
        /// <returns>string</returns>
        public static string GetDisplayName(Type type, string propertyName)
        {
            var property = type.GetProperty(propertyName);
            if (property == null) return null;

            return GetDisplayName(property);
        }

        /// <summary>
        /// This action gives display name of given property of model
        /// </summary>
        /// <param name="property">PropertyInfo: array of properties informaion</param>
        /// <returns>string</returns>
        public static string GetDisplayName(PropertyInfo property)
        {
            // return attribute Display Name of given property.
            var attrName = GetAttributeDisplayName(property);
            if (!string.IsNullOrEmpty(attrName))
                return attrName;

            var metaName = GetMetaDisplayName(property);
            if (!string.IsNullOrEmpty(metaName))
                return metaName;

            return property.Name.ToString();
        }

        /// <summary>
        /// Returns property "DisplayAttribute" value.
        /// </summary>
        /// <param name="property"></param>
        /// <returns>string</returns>
        private static string GetAttributeDisplayName(PropertyInfo property)
        {
            foreach (var item in property.CustomAttributes)
            {
                if (item.AttributeType.Name.Equals("DisplayAttribute"))
                {
                    return item.NamedArguments[0].TypedValue.Value.ToString();
                }
            }
            return null;
        }

        //private static string GetAttributeDisplayName(PropertyInfo property)
        //{
        //    var atts = property.GetCustomAttributes(
        //        typeof(DisplayNameAttribute), true);
        //    if (atts.Length == 0)
        //        return null;
        //    return (atts[0] as DisplayNameAttribute).DisplayName;
        //}

        /// <summary>
        /// Returns mata data of attribute DisplayName.
        /// </summary>
        /// <param name="property">PropertyInfo of  property</param>
        /// <returns>string</returns>
        private static string GetMetaDisplayName(PropertyInfo property)
        {
            var atts = property.DeclaringType.GetCustomAttributes(
                typeof(MetadataTypeAttribute), true);
            if (atts.Length == 0)
                return null;

            var metaAttr = atts[0] as MetadataTypeAttribute;
            var metaProperty =
                metaAttr.MetadataClassType.GetProperty(property.Name);
            if (metaProperty == null)
                return null;
            return GetAttributeDisplayName(metaProperty);
        }
    }
}