// 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.Collections.Immutable;
using System.Linq;
using Microsoft.CodeAnalysis.QuickInfo;
using Microsoft.CodeAnalysis.Shared.Extensions;
 
namespace Microsoft.CodeAnalysis.CSharp.QuickInfo;
 
internal static class OnTheFlyDocsUtilities
{
    public static ImmutableArray<OnTheFlyDocsRelevantFileInfo?> GetAdditionalOnTheFlyDocsContext(Solution solution, ISymbol symbol)
    {
        var parameters = symbol.GetParameters();
        var typeArguments = symbol.GetTypeArguments();
 
        var parameterStrings = parameters.Select(parameter =>
        {
            var typeSymbol = parameter.Type;
            return GetOnTheFlyDocsRelevantFileInfo(typeSymbol);
 
        }).ToImmutableArray();
 
        var typeArgumentStrings = typeArguments.Select(typeArgument =>
        {
            return GetOnTheFlyDocsRelevantFileInfo(typeArgument);
 
        }).ToImmutableArray();
 
        return parameterStrings.AddRange(typeArgumentStrings);
 
        OnTheFlyDocsRelevantFileInfo? GetOnTheFlyDocsRelevantFileInfo(ITypeSymbol typeSymbol)
        {
            var typeSyntaxReference = typeSymbol.DeclaringSyntaxReferences.FirstOrDefault();
            if (typeSyntaxReference is not null)
            {
                var typeSpan = typeSyntaxReference.Span;
                var syntaxReferenceDocument = solution.GetDocument(typeSyntaxReference.SyntaxTree);
                if (syntaxReferenceDocument is not null)
                {
                    return new OnTheFlyDocsRelevantFileInfo(syntaxReferenceDocument, typeSpan);
                }
            }
 
            return null;
        }
    }
}