refactor: Common components are moved to the Common library.

src/ZonyLrcTools.Common/Infrastructure/IO/FileScanner.cs

@@ -0,0 +1,65 @@
+using System.Collections.Concurrent;
+using Microsoft.Extensions.Logging;
+using Microsoft.Extensions.Logging.Abstractions;
+using ZonyLrcTools.Common.Infrastructure.DependencyInject;
+using ZonyLrcTools.Common.Infrastructure.Exceptions;
+using ZonyLrcTools.Common.Infrastructure.Extensions;
+
+namespace ZonyLrcTools.Common.Infrastructure.IO
+{
+    public class FileScanner : IFileScanner, ITransientDependency
+    {
+        public ILogger<FileScanner> Logger { get; set; }
+
+        public FileScanner()
+        {
+            Logger = NullLogger<FileScanner>.Instance;
+        }
+
+        public Task<List<FileScannerResult>> ScanAsync(string path, IEnumerable<string> extensions)
+        {
+            if (extensions == null || !extensions.Any())
+            {
+                throw new ErrorCodeException(ErrorCodes.FileSuffixIsEmpty);
+            }
+
+            if (!Directory.Exists(path))
+            {
+                throw new ErrorCodeException(ErrorCodes.DirectoryNotExist);
+            }
+
+            var files = new List<FileScannerResult>();
+            foreach (var extension in extensions)
+            {
+                var tempResult = new ConcurrentBag<string>();
+                SearchFile(tempResult, path, extension);
+
+                files.Add(new FileScannerResult(
+                    Path.GetExtension(extension) ?? throw new ErrorCodeException(ErrorCodes.UnableToGetTheFileExtension),
+                    tempResult.ToList()));
+            }
+
+            return Task.FromResult(files);
+        }
+
+        private void SearchFile(ConcurrentBag<string> files, string folder, string extension)
+        {
+            try
+            {
+                foreach (var file in Directory.GetFiles(folder, extension))
+                {
+                    files.Add(file);
+                }
+
+                foreach (var directory in Directory.GetDirectories(folder))
+                {
+                    SearchFile(files, directory, extension);
+                }
+            }
+            catch (Exception e)
+            {
+                Logger.LogWarningWithErrorCode(ErrorCodes.ScanFileError, e);
+            }
+        }
+    }
+}