// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
// See the LICENSE file in the project root for more information.
 
using System;
using System.Diagnostics.CodeAnalysis;
using Microsoft.CodeAnalysis.Diagnostics;
 
namespace Microsoft.CodeAnalysis
{
    /// <remarks>
    /// Assembly path is used as a part of a generator identity to deal with the case that the user accidentally installed the same
    /// generator twice from two different paths, or actually has two different generators that just happened to use the same name.
    /// In the wild we've seen cases where a user has a broken project or build that results in the same generator being added twice;
    /// we aren't going to try to deduplicate those anywhere since currently the compiler does't do any deduplication either:
    /// you'll simply get duplicate outputs which might collide and cause compile errors. If https://github.com/dotnet/roslyn/issues/56619
    /// is addressed, we can potentially match the compiler behavior by taking a different approach here.
    /// </remarks>
    internal record struct SourceGeneratorIdentity
    {
        public required string AssemblyName { get; init; }
        public required string? AssemblyPath { get; init; }
        public required Version AssemblyVersion { get; init; }
        public required string TypeName { get; init; }
 
        [SetsRequiredMembers]
        public SourceGeneratorIdentity(ISourceGenerator generator, AnalyzerReference analyzerReference)
        {
            var generatorType = generator.GetGeneratorType();
            var assembly = generatorType.Assembly;
            var assemblyName = assembly.GetName();
            AssemblyName = assemblyName.Name!;
            AssemblyPath = analyzerReference.FullPath;
            AssemblyVersion = assemblyName.Version!;
            TypeName = generatorType.FullName!;
        }
 
        public static string GetGeneratorTypeName(ISourceGenerator generator)
        {
            return generator.GetGeneratorType().FullName!;
        }
    }
}