// 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.
 
#nullable disable
 
using System.Collections.Immutable;
 
namespace Microsoft.CodeAnalysis.Diagnostics
{
 
    internal abstract class AbstractDiagnosticPropertiesService : IDiagnosticPropertiesService
    {
        public ImmutableDictionary<string, string> GetAdditionalProperties(Diagnostic diagnostic)
            => GetAdditionalProperties(diagnostic, GetCompilation());
 
        protected abstract Compilation GetCompilation();
 
        private static ImmutableDictionary<string, string> GetAdditionalProperties(
            Diagnostic diagnostic,
            Compilation compilation)
        {
            var assemblyIds = compilation.GetUnreferencedAssemblyIdentities(diagnostic);
            var requiredVersion = Compilation.GetRequiredLanguageVersion(diagnostic);
            if (assemblyIds.IsDefaultOrEmpty && requiredVersion == null)
            {
                return null;
            }
 
            var result = ImmutableDictionary.CreateBuilder<string, string>();
            if (!assemblyIds.IsDefaultOrEmpty)
            {
                result.Add(
                    DiagnosticPropertyConstants.UnreferencedAssemblyIdentity,
                    assemblyIds[0].GetDisplayName());
            }
 
            if (requiredVersion != null)
            {
                result.Add(
                    DiagnosticPropertyConstants.RequiredLanguageVersion,
                    requiredVersion);
            }
 
            return result.ToImmutable();
        }
    }
}