// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
 
using System.Diagnostics.CodeAnalysis;
using Microsoft.VisualStudio.Utilities;
 
namespace Microsoft.VisualStudio.Razor.LanguageClient;
 
internal abstract class RazorFilePathToContentTypeProviderBase(
    IContentTypeRegistryService contentTypeRegistryService,
    ILspEditorFeatureDetector lspEditorFeatureDetector) : IFilePathToContentTypeProvider
{
    private readonly IContentTypeRegistryService _contentTypeRegistryService = contentTypeRegistryService;
    private readonly ILspEditorFeatureDetector _lspEditorFeatureDetector = lspEditorFeatureDetector;
 
    public bool TryGetContentTypeForFilePath(string filePath, [NotNullWhen(true)] out IContentType? contentType)
    {
        if (UseLSPEditor(filePath))
        {
            contentType = _contentTypeRegistryService.GetContentType(RazorConstants.RazorLSPContentTypeName);
            return true;
        }
 
        contentType = null;
        return false;
    }
 
    private bool UseLSPEditor(string filePath)
    {
        // When cohosting is on, it's on for all non .NET Framework projects, regardless of feature flags or
        // project capabilities. If the file is not in a project (e.g. loose files, left side of diff), we
        // also want to use the LSP editor, even though the .NET capability check would fail.
        if (_lspEditorFeatureDetector.IsDotNetCoreProject(filePath) is { } check &&
            (!check.IsInProject || check.HasCapability))
        {
            return true;
        }
 
        // Otherwise, we just check for the lack of feature flag feature or project capability.
        if (_lspEditorFeatureDetector.IsLspEditorSupported(filePath))
        {
            return true;
        }
 
        return false;
    }
}