// Copyright (c) .NET Foundation. All rights reserved.
// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.

using System.IO;
using Xunit;
using Xunit.Abstractions;

namespace Templates.Test
{
    public class ByteOrderMarkTest
    {
        private readonly ITestOutputHelper _output;
        private readonly char _separator = Path.DirectorySeparatorChar;

        public ByteOrderMarkTest(ITestOutputHelper output)
        {
            _output = output;
        }

        [Theory]
        [InlineData("Microsoft.AspNetCore.SpaTemplates")]
        [InlineData("Microsoft.DotNet.Web.ProjectTemplates")]
        [InlineData("Microsoft.DotNet.Web.Spa.ProjectTemplates")]
        public void CheckForByteOrderMarkSpaTemplates(string projectType)
        {
            var currentDirectory = Directory.GetCurrentDirectory();
            var repositoryPath = Directory.GetParent(currentDirectory).Parent.Parent.Parent.Parent.FullName;
            var srcDirectory = Path.Combine(repositoryPath, "src");
            var path = Path.Combine(projectType, "content");
            var directories = Directory.GetDirectories(Path.Combine(srcDirectory, path), "*Sharp");

            var filesWithBOMCharactersPresent = false;
            foreach (var directory in directories)
            {
                var files = Directory.GetFiles(directory, "*.json");
                foreach (var file in files)
                {
                    var filePath = Path.GetFullPath(file);
                    var fileStream = new FileStream(filePath, FileMode.Open);

                    var bytes = new byte[3];
                    fileStream.Read(bytes, 0, 3);

                    // Check for UTF8 BOM 0xEF,0xBB,0xBF
                    if (bytes[0] == 0xEF && bytes[1] == 0xBB && bytes[2] == 0xBF)
                    {
                        _output.WriteLine($"File {filePath} has UTF-8 BOM characters.");
                        filesWithBOMCharactersPresent = true;
                    }
                    // Check for UTF16 BOM 0xFF, 0xFE
                    if (bytes[0] == 0xFF && bytes[1] == 0xFE)
                    {
                        _output.WriteLine($"File {filePath} has UTF-16 BOM characters.");
                        filesWithBOMCharactersPresent = true;
                    }
                }
            }

            Assert.False(filesWithBOMCharactersPresent);
        }
    }
}