// Copyright (c) .NET Foundation and contributors. All rights reserved.
// Licensed under the MIT license. See LICENSE file in the project root for full license information.

using System.Text;
using Mono.Cecil;

namespace Mono.Linker
{
    /// <summary>
    ///  Generates a signature for a member, in the format used for C# Documentation Comments:
    ///  https://github.com/dotnet/csharplang/blob/master/spec/documentation-comments.md#id-string-format
    ///  Adapted from Roslyn's DocumentationCommentIDVisitor:
    ///  https://github.com/dotnet/roslyn/blob/master/src/Compilers/CSharp/Portable/DocumentationComments/DocumentationCommentIDVisitor.cs
    /// </summary>
    internal sealed partial class DocumentationSignatureGenerator
    {
        internal const string MethodPrefix = "M:";
        internal const string FieldPrefix = "F:";
        internal const string EventPrefix = "E:";
        internal const string PropertyPrefix = "P:";
        internal const string TypePrefix = "T:";

        private DocumentationSignatureGenerator()
        {
        }

        public static void VisitMember(IMemberDefinition member, StringBuilder builder, ITryResolveMetadata resolver)
        {
            switch (member.MetadataToken.TokenType)
            {
                case TokenType.TypeDef:
                    VisitTypeDefinition((TypeDefinition)member, builder, resolver);
                    break;
                case TokenType.Method:
                    VisitMethod((MethodDefinition)member, builder, resolver);
                    break;
                case TokenType.Property:
                    VisitProperty((PropertyDefinition)member, builder, resolver);
                    break;
                case TokenType.Field:
                    VisitField((FieldDefinition)member, builder, resolver);
                    break;
                case TokenType.Event:
                    VisitEvent((EventDefinition)member, builder, resolver);
                    break;
                default:
                    break;
            }
        }

        private static void VisitMethod(MethodDefinition method, StringBuilder builder, ITryResolveMetadata resolver)
        {
            builder.Append(MethodPrefix);
            PartVisitor.Instance.VisitMethodDefinition(method, builder, resolver);
        }

        private static void VisitField(FieldDefinition field, StringBuilder builder, ITryResolveMetadata resolver)
        {
            builder.Append(FieldPrefix);
            PartVisitor.Instance.VisitField(field, builder, resolver);
        }

        private static void VisitEvent(EventDefinition evt, StringBuilder builder, ITryResolveMetadata resolver)
        {
            builder.Append(EventPrefix);
            PartVisitor.Instance.VisitEvent(evt, builder, resolver);
        }

        private static void VisitProperty(PropertyDefinition property, StringBuilder builder, ITryResolveMetadata resolver)
        {
            builder.Append(PropertyPrefix);
            PartVisitor.Instance.VisitProperty(property, builder, resolver);
        }

        private static void VisitTypeDefinition(TypeDefinition type, StringBuilder builder, ITryResolveMetadata resolver)
        {
            builder.Append(TypePrefix);
            PartVisitor.Instance.VisitTypeReference(type, builder, resolver);
        }
    }
}