// 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.Threading;
using Roslyn.LanguageServer.Protocol;
 
namespace Microsoft.CodeAnalysis.LanguageServer.Handler.SpellCheck;
 
[Method(VSInternalMethods.TextDocumentSpellCheckableRangesName)]
internal sealed class DocumentSpellCheckHandler : AbstractSpellCheckHandler<VSInternalDocumentSpellCheckableParams, VSInternalSpellCheckableRangeReport>
{
    public override TextDocumentIdentifier GetTextDocumentIdentifier(VSInternalDocumentSpellCheckableParams requestParams)
        => requestParams.TextDocument;
 
    protected override VSInternalSpellCheckableRangeReport CreateReport(TextDocumentIdentifier identifier, int[]? ranges, string? resultId)
        => new()
        {
            Ranges = ranges,
            ResultId = resultId,
        };
 
    protected override ImmutableArray<PreviousPullResult>? GetPreviousResults(VSInternalDocumentSpellCheckableParams requestParams)
    {
        if (requestParams.PreviousResultId != null && requestParams.TextDocument != null)
        {
            return ImmutableArray.Create(new PreviousPullResult(requestParams.PreviousResultId, requestParams.TextDocument));
        }
 
        // The client didn't provide us with a previous result to look for, so we can't lookup anything.
        return null;
    }
 
    protected override ImmutableArray<Document> GetOrderedDocuments(RequestContext context, CancellationToken cancellationToken)
        => GetRequestedDocument(context);
 
    internal static ImmutableArray<Document> GetRequestedDocument(RequestContext context)
    {
        // For the single document case, that is the only doc we want to process.
        //
        // Note: context.Document may be null in the case where the client is asking about a document that we have
        // since removed from the workspace.  In this case, we don't really have anything to process.
        // GetPreviousResults will be used to properly realize this and notify the client that the doc is gone.
        //
        // Only consider open documents here (and only closed ones in the WorkspaceSpellCheckingHandler).  Each
        // handler treats those as separate worlds that they are responsible for.
        if (context.Document == null)
        {
            context.TraceInformation("Ignoring spell check request because no document was provided");
            return [];
        }
 
        if (!context.IsTracking(context.Document.GetURI()))
        {
            context.TraceInformation($"Ignoring spell check request for untracked document: {context.Document.GetURI()}");
            return [];
        }
 
        return [context.Document];
    }
}