// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.

using Microsoft.Build.Framework;
using System.IO;
using XliffTasks.Model;

namespace XliffTasks.Tasks;

[MSBuildMultiThreadableTask]
public sealed class UpdateXlf : XlfTask
{
    [Required]
    public ITaskItem[] Sources { get; set; }

    [Required]
    public string[] Languages { get; set; }

    [Required]
    public bool AllowModification { get; set; }

    private const string HowToUpdate =
        "Run `msbuild /t:UpdateXlf` to update .xlf files or set UpdateXlfOnBuild=true"
        + " to update them on every build, but note that it is strongly discouraged to set"
        + " UpdateXlfOnBuild=true in official/CI build environments as they should not"
        + " modify source code during the build.";

    protected override void ExecuteCore()
    {
        foreach (ITaskItem item in Sources)
        {
            string sourcePath = item.ItemSpec;
            string sourceDocumentPath = item.GetMetadataOrDefault(MetadataKey.SourceDocumentPath, item.ItemSpec);
            string sourceFormat = item.GetMetadataOrThrow(MetadataKey.XlfSourceFormat);
            TranslatableDocument sourceDocument = XlfTask.LoadSourceDocument(TaskEnvironment.GetAbsolutePath(sourcePath), sourceFormat);
            string sourceDocumentId = XlfTask.GetSourceDocumentId(sourcePath);

            foreach (string language in Languages)
            {
                string xlfPath = XlfTask.GetXlfPath(sourceDocumentPath, language);
                AbsolutePath absoluteXlfPath = TaskEnvironment.GetAbsolutePath(xlfPath);
                XlfDocument xlfDocument;

                try
                {
                    xlfDocument = XlfTask.LoadXlfDocument(absoluteXlfPath, language, createIfNonExistent: AllowModification);
                }
                // Document.Load opens the file through FileInfo.FullName, which canonicalizes it,
                // so compare against the canonical form rather than the raw absolute path.
                catch (FileNotFoundException fileNotFoundEx) when (fileNotFoundEx.FileName == absoluteXlfPath.GetCanonicalForm().Value)
                {
                    Release.Assert(!AllowModification);
                    throw new BuildErrorException($"'{xlfPath}' for '{sourcePath}' does not exist. {HowToUpdate}");
                }
                catch (System.Xml.XmlException xmlEx)
                {
                    throw new BuildErrorException($"Unable to load file: {xmlEx.Message}")
                    {
                        RelatedFile = xlfPath
                    };
                }

                bool updated = xlfDocument.Update(sourceDocument, sourceDocumentId);

                if (!updated)
                {
                    continue; // no changes
                }

                if (!AllowModification)
                {
                    throw new BuildErrorException($"'{xlfPath}' is out-of-date with '{sourcePath}'. {HowToUpdate}");
                }

                Directory.CreateDirectory(Path.GetDirectoryName(absoluteXlfPath));
                xlfDocument.Save(new FileInfo(absoluteXlfPath));
            }
        }
    }
}