/*
    Copyright (C) 2014-2019 de4dot@gmail.com

    This file is part of dnSpy

    dnSpy is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    dnSpy is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with dnSpy.  If not, see <http://www.gnu.org/licenses/>.
*/

using System;
using System.Diagnostics;
using System.Linq;
using dnSpy.Contracts.MVVM;
using dnSpy.Contracts.Settings.Dialog;
using dnSpy.Decompiler.ILSpy.Properties;
using ICSharpCode.Decompiler;

namespace dnSpy.Decompiler.ILSpy.Settings {
	sealed class CSharpDecompilerSettingsPage : AppSettingsPage, IAppSettingsPage2 {
		readonly DecompilerSettings _global_decompilerSettings;
		readonly DecompilerSettings decompilerSettings;

		public override double Order => AppSettingsConstants.ORDER_DECOMPILER_SETTINGS_ILSPY_CSHARP;
		public DecompilerSettings Settings => decompilerSettings;
		public override Guid ParentGuid => new Guid(AppSettingsConstants.GUID_DECOMPILER);
		public override Guid Guid => new Guid("8929CE8E-7E2C-4701-A8BA-42F70363872C");
		public override string Title => "C# / Visual Basic (ILSpy)";
		public override object? UIObject => this;

		public DecompilationObjectVM[] DecompilationObjectsArray => decompilationObjectVMs2;
		readonly DecompilationObjectVM[] decompilationObjectVMs;
		readonly DecompilationObjectVM[] decompilationObjectVMs2;

		public DecompilationObjectVM DecompilationObject0 {
			get => decompilationObjectVMs[0];
			set => SetDecompilationObject(0, value);
		}

		public DecompilationObjectVM DecompilationObject1 {
			get => decompilationObjectVMs[1];
			set => SetDecompilationObject(1, value);
		}

		public DecompilationObjectVM DecompilationObject2 {
			get => decompilationObjectVMs[2];
			set => SetDecompilationObject(2, value);
		}

		public DecompilationObjectVM DecompilationObject3 {
			get => decompilationObjectVMs[3];
			set => SetDecompilationObject(3, value);
		}

		public DecompilationObjectVM DecompilationObject4 {
			get => decompilationObjectVMs[4];
			set => SetDecompilationObject(4, value);
		}

		void SetDecompilationObject(int index, DecompilationObjectVM newValue) {
			Debug2.Assert(newValue is not null);
			if (newValue is null)
				throw new ArgumentNullException(nameof(newValue));
			if (decompilationObjectVMs[index] == newValue)
				return;

			int otherIndex = Array.IndexOf(decompilationObjectVMs, newValue);
			Debug.Assert(otherIndex >= 0);
			if (otherIndex >= 0) {
				decompilationObjectVMs[otherIndex] = decompilationObjectVMs[index];
				decompilationObjectVMs[index] = newValue;

				OnPropertyChanged($"DecompilationObject{otherIndex}");
			}
			OnPropertyChanged($"DecompilationObject{index}");
		}

		public CSharpDecompilerSettingsPage(DecompilerSettings decompilerSettings) {
			_global_decompilerSettings = decompilerSettings;
			this.decompilerSettings = decompilerSettings.Clone();

			var defObjs = typeof(DecompilationObject).GetEnumValues().Cast<DecompilationObject>().ToArray();
			decompilationObjectVMs = new DecompilationObjectVM[defObjs.Length];
			for (int i = 0; i < defObjs.Length; i++)
				decompilationObjectVMs[i] = new DecompilationObjectVM(defObjs[i], ToString(defObjs[i]));
			decompilationObjectVMs2 = decompilationObjectVMs.ToArray();

			DecompilationObject0 = decompilationObjectVMs.First(a => a.Object == decompilerSettings.DecompilationObject0);
			DecompilationObject1 = decompilationObjectVMs.First(a => a.Object == decompilerSettings.DecompilationObject1);
			DecompilationObject2 = decompilationObjectVMs.First(a => a.Object == decompilerSettings.DecompilationObject2);
			DecompilationObject3 = decompilationObjectVMs.First(a => a.Object == decompilerSettings.DecompilationObject3);
			DecompilationObject4 = decompilationObjectVMs.First(a => a.Object == decompilerSettings.DecompilationObject4);
		}

		static string ToString(DecompilationObject o) {
			switch (o) {
			case DecompilationObject.NestedTypes:	return dnSpy_Decompiler_ILSpy_Resources.DecompilationOrder_NestedTypes;
			case DecompilationObject.Fields:		return dnSpy_Decompiler_ILSpy_Resources.DecompilationOrder_Fields;
			case DecompilationObject.Events:		return dnSpy_Decompiler_ILSpy_Resources.DecompilationOrder_Events;
			case DecompilationObject.Properties:	return dnSpy_Decompiler_ILSpy_Resources.DecompilationOrder_Properties;
			case DecompilationObject.Methods:		return dnSpy_Decompiler_ILSpy_Resources.DecompilationOrder_Methods;
			default:
				Debug.Fail("Shouldn't be here");
				return "???";
			}
		}

		[Flags]
		enum RefreshFlags {
			ShowMember			= 0x00000001,
			ILAst				= 0x00000002,
			CSharp				= 0x00000004,
			VB					= 0x00000008,
			DecompileAll		= ILAst | CSharp | VB,
		}

		public override void OnApply() => throw new InvalidOperationException();
		public void OnApply(IAppRefreshSettings appRefreshSettings) {
			RefreshFlags flags = 0;
			var g = _global_decompilerSettings;
			var d = decompilerSettings;

			d.DecompilationObject0 = DecompilationObject0.Object;
			d.DecompilationObject1 = DecompilationObject1.Object;
			d.DecompilationObject2 = DecompilationObject2.Object;
			d.DecompilationObject3 = DecompilationObject3.Object;
			d.DecompilationObject4 = DecompilationObject4.Object;

			if (g.AnonymousMethods != d.AnonymousMethods) flags |= RefreshFlags.ILAst | RefreshFlags.ShowMember;
			if (g.ExpressionTrees != d.ExpressionTrees) flags |= RefreshFlags.ILAst;
			if (g.YieldReturn != d.YieldReturn) flags |= RefreshFlags.ILAst | RefreshFlags.ShowMember;
			if (g.AsyncAwait != d.AsyncAwait) flags |= RefreshFlags.ILAst | RefreshFlags.ShowMember;
			if (g.AutomaticProperties != d.AutomaticProperties) flags |= RefreshFlags.CSharp | RefreshFlags.ShowMember;
			if (g.AutomaticEvents != d.AutomaticEvents) flags |= RefreshFlags.CSharp | RefreshFlags.ShowMember;
			if (g.UsingStatement != d.UsingStatement) flags |= RefreshFlags.CSharp;
			if (g.ForEachStatement != d.ForEachStatement) flags |= RefreshFlags.CSharp;
			if (g.LockStatement != d.LockStatement) flags |= RefreshFlags.CSharp;
			if (g.SwitchStatementOnString != d.SwitchStatementOnString) flags |= RefreshFlags.CSharp | RefreshFlags.ShowMember;
			if (g.UsingDeclarations != d.UsingDeclarations) flags |= RefreshFlags.CSharp;
			if (g.QueryExpressions != d.QueryExpressions) flags |= RefreshFlags.CSharp;
			if (g.FullyQualifyAmbiguousTypeNames != d.FullyQualifyAmbiguousTypeNames) flags |= RefreshFlags.CSharp;
			if (g.FullyQualifyAllTypes != d.FullyQualifyAllTypes) flags |= RefreshFlags.CSharp;
			if (g.UseDebugSymbols != d.UseDebugSymbols) flags |= RefreshFlags.DecompileAll;
			if (g.ObjectOrCollectionInitializers != d.ObjectOrCollectionInitializers) flags |= RefreshFlags.ILAst;
			if (g.ShowXmlDocumentation != d.ShowXmlDocumentation) flags |= RefreshFlags.DecompileAll;
			if (g.RemoveEmptyDefaultConstructors != d.RemoveEmptyDefaultConstructors) flags |= RefreshFlags.CSharp;
			if (g.IntroduceIncrementAndDecrement != d.IntroduceIncrementAndDecrement) flags |= RefreshFlags.ILAst;
			if (g.MakeAssignmentExpressions != d.MakeAssignmentExpressions) flags |= RefreshFlags.ILAst;
			if (g.AlwaysGenerateExceptionVariableForCatchBlocksUnlessTypeIsObject != d.AlwaysGenerateExceptionVariableForCatchBlocksUnlessTypeIsObject) flags |= RefreshFlags.ILAst;
			if (g.ShowTokenAndRvaComments != d.ShowTokenAndRvaComments) flags |= RefreshFlags.DecompileAll;
			if (g.DecompilationObject0 != d.DecompilationObject0) flags |= RefreshFlags.CSharp;
			if (g.DecompilationObject1 != d.DecompilationObject1) flags |= RefreshFlags.CSharp;
			if (g.DecompilationObject2 != d.DecompilationObject2) flags |= RefreshFlags.CSharp;
			if (g.DecompilationObject3 != d.DecompilationObject3) flags |= RefreshFlags.CSharp;
			if (g.DecompilationObject4 != d.DecompilationObject4) flags |= RefreshFlags.CSharp;
			if (g.SortMembers != d.SortMembers) flags |= RefreshFlags.CSharp;
			if (g.ForceShowAllMembers != d.ForceShowAllMembers) flags |= RefreshFlags.CSharp | RefreshFlags.ShowMember;
			if (g.SortSystemUsingStatementsFirst != d.SortSystemUsingStatementsFirst) flags |= RefreshFlags.CSharp;
			if (g.MaxArrayElements != d.MaxArrayElements) flags |= RefreshFlags.CSharp;
			if (g.MaxStringLength != d.MaxStringLength) flags |= RefreshFlags.CSharp;
			if (g.SortCustomAttributes != d.SortCustomAttributes) flags |= RefreshFlags.CSharp;
			if (g.UseSourceCodeOrder != d.UseSourceCodeOrder) flags |= RefreshFlags.CSharp;
			if (g.AllowFieldInitializers != d.AllowFieldInitializers) flags |= RefreshFlags.CSharp;
			if (g.OneCustomAttributePerLine != d.OneCustomAttributePerLine) flags |= RefreshFlags.CSharp;
			if (g.TypeAddInternalModifier != d.TypeAddInternalModifier) flags |= RefreshFlags.CSharp;
			if (g.MemberAddPrivateModifier != d.MemberAddPrivateModifier) flags |= RefreshFlags.CSharp;
			if (g.HexadecimalNumbers != d.HexadecimalNumbers) flags |= RefreshFlags.CSharp;

			if ((flags & RefreshFlags.ShowMember) != 0)
				appRefreshSettings.Add(AppSettingsConstants.REFRESH_LANGUAGE_SHOWMEMBER);
			if ((flags & RefreshFlags.ILAst) != 0)
				appRefreshSettings.Add(SettingsConstants.REDECOMPILE_ILAST_ILSPY_CODE);
			if ((flags & RefreshFlags.CSharp) != 0)
				appRefreshSettings.Add(SettingsConstants.REDECOMPILE_CSHARP_ILSPY_CODE);
			if ((flags & RefreshFlags.VB) != 0)
				appRefreshSettings.Add(SettingsConstants.REDECOMPILE_VB_ILSPY_CODE);

			decompilerSettings.CopyTo(_global_decompilerSettings);
		}

		public override string[]? GetSearchStrings() => DecompilationObjectsArray.Select(a => a.Text).ToArray();
	}

	sealed class DecompilationObjectVM : ViewModelBase {
		public DecompilationObject Object { get; }
		public string Text { get; }

		public DecompilationObjectVM(DecompilationObject decompilationObject, string text) {
			Object = decompilationObject;
			Text = text;
		}
	}
}