/*************************************************************************
 * ModernUO                                                              *
 * Copyright 2019-2021 - ModernUO Development Team                       *
 * Email: hi@modernuo.com                                                *
 * File: SymbolMetadata.UO.cs                                            *
 *                                                                       *
 * This program 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.                                   *
 *                                                                       *
 * You should have received a copy of the GNU General Public License     *
 * along with this program.  If not, see <http://www.gnu.org/licenses/>. *
 *************************************************************************/

using System.Collections.Immutable;
using System.Linq;
using Microsoft.CodeAnalysis;

namespace SerializationGenerator
{
    public static partial class SymbolMetadata
    {
        public const string INVALIDATEPROPERTIES_ATTRIBUTE = "Server.InvalidatePropertiesAttribute";
        public const string AFTERDESERIALIZATION_ATTRIBUTE = "Server.AfterDeserializationAttribute";
        public const string SERIALIZABLE_ATTRIBUTE = "Server.SerializableAttribute";
        public const string EMBEDDED_SERIALIZABLE_ATTRIBUTE = "Server.EmbeddedSerializableAttribute";
        public const string SERIALIZABLE_PARENT_ATTRIBUTE = "Server.SerializableParentAttribute";
        public const string SERIALIZABLE_FIELD_ATTRIBUTE = "Server.SerializableFieldAttribute";
        public const string SERIALIZABLE_FIELD_ATTR_ATTRIBUTE = "Server.SerializableFieldAttrAttribute";
        public const string SERIALIZABLE_INTERFACE = "Server.ISerializable";
        public const string GENERIC_WRITER_INTERFACE = "Server.IGenericWriter";
        public const string GENERIC_READER_INTERFACE = "Server.IGenericReader";
        public const string DELTA_DATE_TIME_ATTRIBUTE = "Server.DeltaDateTimeAttribute";
        public const string INTERN_STRING_ATTRIBUTE = "Server.InternStringAttribute";
        public const string ENCODED_INT_ATTRIBUTE = "Server.EncodedIntAttribute";
        public const string TIDY_ATTRIBUTE = "Server.TidyAttribute";
        public const string POINT2D_STRUCT = "Server.Point2D";
        public const string POINT3D_STRUCT = "Server.Point3D";
        public const string RECTANGLE2D_STRUCT = "Server.Rectangle2D";
        public const string RECTANGLE3D_STRUCT = "Server.Rectangle3D";
        public const string RACE_CLASS = "Server.Race";
        public const string MAP_CLASS = "Server.Map";
        public const string TIMER_CLASS = "Server.Timer";
        public const string TIMER_DRIFT_ATTRIBUTE = "Server.TimerDriftAttribute";
        public const string DESERIALIZE_TIMER_FIELD_ATTRIBUTE = "Server.DeserializeTimerFieldAttribute";

        public static bool IsTimerDrift(this AttributeData attr, Compilation compilation) =>
            attr?.IsAttribute(compilation.GetTypeByMetadataName(TIMER_DRIFT_ATTRIBUTE)) == true;

        public static bool IsTimer(this ITypeSymbol symbol, Compilation compilation) =>
            symbol.CanBeConstructedFrom(compilation.GetTypeByMetadataName(TIMER_CLASS));

        public static bool IsEncodedInt(this AttributeData attr, Compilation compilation) =>
            attr?.IsAttribute(compilation.GetTypeByMetadataName(ENCODED_INT_ATTRIBUTE)) == true;

        public static bool IsDeltaDateTime(this AttributeData attr, Compilation compilation) =>
            attr?.IsAttribute(compilation.GetTypeByMetadataName(DELTA_DATE_TIME_ATTRIBUTE)) == true;

        public static bool IsInternString(this AttributeData attr, Compilation compilation) =>
            attr?.IsAttribute(compilation.GetTypeByMetadataName(INTERN_STRING_ATTRIBUTE)) == true;

        public static bool IsTidy(this AttributeData attr, Compilation compilation) =>
            attr?.IsAttribute(compilation.GetTypeByMetadataName(TIDY_ATTRIBUTE)) == true;

        public static bool IsAttribute(this AttributeData attr, ISymbol symbol) =>
            attr?.AttributeClass?.Equals(symbol, SymbolEqualityComparer.Default) == true;

        public static bool IsEnum(this ITypeSymbol symbol) =>
            symbol.SpecialType == SpecialType.System_Enum || symbol.TypeKind == TypeKind.Enum;

        public static bool HasSerializableInterface(
            this ITypeSymbol symbol,
            Compilation compilation,
            ImmutableArray<INamedTypeSymbol> serializableTypes
        ) =>
            symbol.ContainsInterface(compilation.GetTypeByMetadataName(SERIALIZABLE_INTERFACE)) ||
            serializableTypes.Contains(symbol);

        public static bool Contains(this ImmutableArray<INamedTypeSymbol> symbols, ITypeSymbol symbol) =>
            symbol is INamedTypeSymbol namedSymbol &&
            symbols.Contains(namedSymbol, SymbolEqualityComparer.Default);

        public static bool HasGenericReaderCtor(
            this INamedTypeSymbol symbol,
            Compilation compilation,
            ISymbol? parentSymbol,
            out bool requiresParent
        )
        {
            var genericReaderInterface = compilation.GetTypeByMetadataName(GENERIC_READER_INTERFACE);
            var genericCtor = symbol.Constructors.FirstOrDefault(
                m => !m.IsStatic &&
                     m.MethodKind == MethodKind.Constructor &&
                     m.Parameters.Length <= 2 &&
                     SymbolEqualityComparer.Default.Equals(m.Parameters[0].Type, genericReaderInterface)
            );

            requiresParent = genericCtor?.Parameters.Length == 2 && SymbolEqualityComparer.Default.Equals(genericCtor.Parameters[1].Type, parentSymbol);
            return genericCtor != null;
        }

        public static bool HasPublicSerializeMethod(
            this ITypeSymbol symbol,
            Compilation compilation,
            ImmutableArray<INamedTypeSymbol> serializableTypes
        )
        {
            if (symbol.HasSerializableInterface(compilation, serializableTypes))
            {
                return true;
            }

            var genericWriterInterface = compilation.GetTypeByMetadataName(GENERIC_WRITER_INTERFACE);

            return symbol.GetAllMethods("Serialize")
                .Any(
                    m => !m.IsStatic &&
                         m.ReturnsVoid &&
                         m.Parameters.Length == 1 &&
                         SymbolEqualityComparer.Default.Equals(m.Parameters[0].Type, genericWriterInterface) &&
                         m.DeclaredAccessibility == Accessibility.Public
                );
        }

        public static bool HasPublicDeserializeMethod(
            this ITypeSymbol symbol,
            Compilation compilation,
            ImmutableArray<INamedTypeSymbol> serializableTypes
        )
        {
            if (symbol.HasSerializableInterface(compilation, serializableTypes))
            {
                return true;
            }

            var genericReaderInterface = compilation.GetTypeByMetadataName(GENERIC_READER_INTERFACE);

            return symbol.GetAllMethods("Deserialize")
                .Any(
                    m => !m.IsStatic &&
                         m.ReturnsVoid &&
                         m.Parameters.Length == 1 &&
                         SymbolEqualityComparer.Default.Equals(m.Parameters[0].Type, genericReaderInterface) &&
                         m.DeclaredAccessibility == Accessibility.Public
                );
        }

        public static bool IsPoint2D(this ISymbol symbol, Compilation compilation) =>
            symbol.Equals(
                compilation.GetTypeByMetadataName(POINT2D_STRUCT),
                SymbolEqualityComparer.Default
            );

        public static bool IsPoint3D(this ISymbol symbol, Compilation compilation) =>
            symbol.Equals(
                compilation.GetTypeByMetadataName(POINT3D_STRUCT),
                SymbolEqualityComparer.Default
            );

        public static bool IsRectangle2D(this ISymbol symbol, Compilation compilation) =>
            symbol.Equals(
                compilation.GetTypeByMetadataName(RECTANGLE2D_STRUCT),
                SymbolEqualityComparer.Default
            );

        public static bool IsRectangle3D(this ISymbol symbol, Compilation compilation) =>
            symbol.Equals(
                compilation.GetTypeByMetadataName(RECTANGLE3D_STRUCT),
                SymbolEqualityComparer.Default
            );

        public static bool IsRace(this ISymbol symbol, Compilation compilation) =>
            symbol.Equals(
                compilation.GetTypeByMetadataName(RACE_CLASS),
                SymbolEqualityComparer.Default
            );

        public static bool IsMap(this ISymbol symbol, Compilation compilation) =>
            symbol.Equals(
                compilation.GetTypeByMetadataName(MAP_CLASS),
                SymbolEqualityComparer.Default
            );

        public static AttributeData? GetAttribute(this ISymbol symbol, ISymbol attrSymbol) =>
            symbol
                .GetAttributes()
                .FirstOrDefault(
                    ad => ad.AttributeClass != null && SymbolEqualityComparer.Default.Equals(ad.AttributeClass, attrSymbol)
                );

        public static bool WillBeSerializable(this INamedTypeSymbol classSymbol, Compilation compilation, out AttributeData? attributeData)
        {
            var serializableInterface = compilation.GetTypeByMetadataName(SERIALIZABLE_INTERFACE);

            if (!classSymbol.ContainsInterface(serializableInterface))
            {
                attributeData = null;
                return false;
            }

            var serializableEntityAttribute =
                compilation.GetTypeByMetadataName(SERIALIZABLE_ATTRIBUTE);

            attributeData = classSymbol.GetAttribute(serializableEntityAttribute);
            return attributeData != null;
        }

        public static bool IsEmbeddedSerializable(this INamedTypeSymbol classSymbol, Compilation compilation, out AttributeData? attributeData)
        {
            var embeddedSerializableEntityAttribute =
                compilation.GetTypeByMetadataName(EMBEDDED_SERIALIZABLE_ATTRIBUTE);

            attributeData = classSymbol.GetAttribute(embeddedSerializableEntityAttribute);
            return attributeData != null;
        }
    }
}