using System.ComponentModel;
using System.ComponentModel.DataAnnotations;
using System.Reflection;

namespace Sai.Toolkit.Core.Helpers;

public static class EnumHelpers
{
	/// <summary>
	///     获取当前枚举的值和枚举描述
	/// </summary>
	/// <returns></returns>
	public static List<KeyValuePair<int, string>> GetAll<T>()
		where T : IComparable, IFormattable, IConvertible
	{
		var list = new List<KeyValuePair<int, string>>();
		foreach (var field in typeof(T).GetFields())
		{
			if (field.FieldType.IsEnum)
			{
				var tmp = field.GetValue(null);
				var enumValue = (Enum)tmp;
				var intValue = Convert.ToInt32(enumValue);
				var showName = enumValue.GetDescription();
				list.Add(new KeyValuePair<int, string>(intValue, showName));
			}
		}

		return list;
	}

	/// <summary>
	///     获取当前枚举值的描述，没有描述则返回空字符串
	/// </summary>
	/// <param name="value"></param>
	/// <returns></returns>
	public static string GetDescription(this Enum value)
	{
		var description = string.Empty;
		var fieldInfo = value.GetType().GetField(value.ToString());
		var attr = fieldInfo.GetCustomAttribute<DescriptionAttribute>();
		if (attr != null)
		{
			description = attr.Description;
		}

		return description;
	}

	public static Dictionary<string, T> GetDescriptionEnumMap<T>()
		where T : Enum
	{
		var results = new Dictionary<string, T>();

		var values = Enum.GetValues(typeof(T));

		foreach (T value in values)
		{
			var member = typeof(T).GetMember(value.ToString()).FirstOrDefault();

			if (member is null)
			{
				continue;
			}

			var customAttributes = member.GetCustomAttributes(typeof(DescriptionAttribute), false);

			var name = (customAttributes.FirstOrDefault() as DescriptionAttribute)?.Description;

			if (name != null)
			{
				results.Add(name, value);
			}
		}

		return results;
	}

	public static Dictionary<string, T> GetDisplayEnumDict<T>()
		where T : Enum
	{
		var results = new Dictionary<string, T>();

		var values = Enum.GetValues(typeof(T));

		foreach (T value in values)
		{
			var member = typeof(T).GetMember(value.ToString()).FirstOrDefault();

			if (member is null)
			{
				continue;
			}

			var atts = member.GetCustomAttributes(typeof(DisplayAttribute), false);

			var name = (atts.FirstOrDefault() as DisplayAttribute)?.Name;

			if (name != null)
			{
				results.Add(name, value);
			}
		}

		return results;
	}

	/// <summary>
	///     获取描述的扩展方法
	/// </summary>
	/// <param name="enumObj"></param>
	/// <param name="value">枚举值</param>
	/// <returns></returns>
	public static string GetEnumDescription(this Enum enumObj, int? value)
	{
		var fields = enumObj.GetType().GetFields();
		for (int i = 1, count = fields.Length; i < count; i++)
		{
			if ((int)Enum.Parse(enumObj.GetType(), fields[i].Name) == value)
			{
				var enumAttributes = (DescriptionAttribute[])fields[i].GetCustomAttributes(typeof(DescriptionAttribute), false);
				if (enumAttributes.Length > 0)
				{
					return enumAttributes[0].Description;
				}
			}
		}

		return string.Empty;
	}

	private static void GetInfo(Type enumType)
	{
		_ = Enum.GetValues(enumType); //得到的是枚举类型，用于遍历枚举类

		_ = Enum.GetNames(enumType); //得到的是枚举类的字符串
	}

	public static List<string> TraverseEnum<T>()
	{
		List<string> pName = new();
		foreach (T p in Enum.GetValues(typeof(T)))
		{
			pName.Add(p.ToString());
		}

		return pName;
	}

	public static bool TryParseByDescAttr<T>(string value, out T result)
		where T : Enum
	{
		if (value is null)
		{
			throw new ArgumentNullException(nameof(value));
		}

		var descs = GetDescriptionEnumMap<T>();

		return !descs.TryGetValue(value, out result) ? throw new InvalidEnumArgumentException() : true;
	}

	public static bool TryParseByDisplayAttr<T>(string value, out T result)
		where T : Enum
	{
		if (value is null)
		{
			throw new ArgumentNullException(nameof(value));
		}

		var dict = GetDisplayEnumDict<T>();

		return !dict.TryGetValue(value, out result) ? throw new InvalidEnumArgumentException() : true;
	}
}