Will Pittenger

namespace Org.WillPittenger.AdBlockPlusIniParserWPF.Core.Ctrl.ForEnums
{
	using Ext;

	public class RadioBtnGroup : System.Windows.Controls.StackPanel, System.ComponentModel.INotifyPropertyChanged
	{
		#region Constructors & Destructors
			public RadioBtnGroup()
			{
			}
		#endregion

		#region Delegates
		#endregion

		#region Events
			public event System.ComponentModel.PropertyChangedEventHandler PropertyChanged;
		#endregion

		#region Constants
			public static class PropNames
			{
				public const string strGroupName = "GroupName";

				public const string strTypeOfEnum = "TypeOfEnum";
				public const string strValName = "ValName";
			}
		#endregion

		#region Helper Types
		#endregion

		#region Members
			private static System.Collections.Generic.SortedList<System.Type, Sets.HashSet<string>> allKnownEnumTypes = new System.Collections
				.Generic.SortedList<System.Type, Sets.HashSet<string>>();

			public readonly string strGroupName = System.Guid.NewGuid().ToString();

			public System.Type typeOfEnum = null;
			public string strVal = null;

			#region Dependency Properties
				private static readonly System.Windows.DependencyProperty propGroupName = System.Windows.DependencyProperty.Register(PropNames.strGroupName,
					typeof(string), typeof(RadioBtnGroup));

				private static readonly System.Windows.DependencyProperty propTypeOfEnum = System.Windows.DependencyProperty.Register(PropNames.strTypeOfEnum,
					typeof(string), typeof(RadioBtnGroup));
				private static readonly System.Windows.DependencyProperty propValName = System.Windows.DependencyProperty.Register(PropNames.strValName, typeof(string),
					typeof(RadioBtnGroup));
			#endregion
		#endregion

		#region Properties
			#region Dependency Properties
				public static System.Windows.DependencyProperty GroupNameProperty => propGroupName;

				public static System.Windows.DependencyProperty TypeOfEnumProperty => propTypeOfEnum;
				public static System.Windows.DependencyProperty ValNameProperty = propValName;
			#endregion

			public string GroupName => strGroupName;

			[System.ComponentModel.Category("Common")]
			[System.ComponentModel.DisplayName("Type of Enum")]
			public string TypeOfEnum
			{
				get => typeOfEnum.ToString();

				set
				{
					if(value.IsEmpty())
					{
						typeOfEnum = null;

						return;
					}

					System.Type typeRequested = System.Type.GetType(value + ", Org.WillPittenger.AdBlockPlusIniParserWPF, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null");

					if(typeRequested == null)
					{
						typeOfEnum = null;

						throw new System.Exception("Unable to find requested type.");
					}

					if(!typeRequested.IsEnum)
					{
						typeOfEnum = null;

						throw new System.Exception("Requested type isn't an enum.");
					}

					typeOfEnum = typeRequested;

					if(!allKnownEnumTypes.ContainsKey(typeOfEnum))
						allKnownEnumTypes[typeOfEnum] = new Sets.HashSet<string>(System.Enum.GetNames(typeOfEnum));
				}
			}

			[System.ComponentModel.Category("Common")]
			[System.ComponentModel.DisplayName("Current Selected Value")]
			public string ValName
			{
				get => strVal;

				set
				{
					if(value == null)
						strVal = null;
					else
					{
						if(typeOfEnum == null)
						{
							strVal = null;

							throw new System.Exception("Can't set values until a source type is specified.");
						}

						if(!IsValForEnumTypeValid(value))
						{
							strVal = null;

							throw new System.Exception("Specified value isn't part of the specified type");
						}

						strVal = value;
					}

					FirePropChanged(PropNames.strValName);
				}
			}
		#endregion

		#region Methods
			private void FirePropChanged(string strPropName) => PropertyChanged?.Invoke(this, new System.ComponentModel.PropertyChangedEventArgs(strPropName));

			public EnumType GetValAsEnum<EnumType>()
			{
				if(strVal == null)
					throw new System.Exception("Value of this radio button group is null");

				if(typeof(EnumType) != typeOfEnum)
					throw new System.Exception("Invalid type cast.");

				return (EnumType)System.Enum.Parse(typeof(EnumType), strVal);
			}

			public void SetValFromEnum<EnumType>(EnumType valNew)
			{
				if(typeof(EnumType) != typeOfEnum)
					throw new System.Exception("Invalid value in the specified enum type or this value is from the wrong enum type for this radio button group.");

				strVal = valNew.ToString();
			}

			internal void RegisterBtn(RadioBtn radioRegisterThis)
			{
				System.Diagnostics.Debug.Assert(typeOfEnum != null);
				if(typeOfEnum == null)
					throw new System.Exception("TypeOfNum is still nulll.  Set it before adding radio buttons");

				radioRegisterThis.Checked += OnChildRadioBtnNowChecked;
				radioRegisterThis.GroupName = strGroupName;
			}

			internal bool IsValForEnumTypeValid(string strValToTest) => !(allKnownEnumTypes[typeOfEnum] < strValToTest);
		#endregion

		#region Event Handlers
			private void OnChildRadioBtnNowChecked(object objSender, System.Windows.RoutedEventArgs e)
			{
				System.Diagnostics.Debug.Assert(objSender is RadioBtn);

				RadioBtn radioSender = (RadioBtn)objSender;

				System.Diagnostics.Debug.Assert(radioSender.Val > allKnownEnumTypes[typeOfEnum]);

				strVal = radioSender.Val;
			}
		#endregion
	}
}