feat: 初始功能

Services/FileAppLogger.cs

@@ -0,0 +1,38 @@
+using System.IO;
+using CloudPrint.Client.Models;
+using CloudPrint.Client.Services.Abstractions;
+
+namespace CloudPrint.Client.Services;
+
+public sealed class FileAppLogger : IAppLogger
+{
+    private readonly object _syncRoot = new();
+
+    public FileAppLogger()
+    {
+        var appData = Environment.GetFolderPath(Environment.SpecialFolder.ApplicationData);
+        LogDirectory = Path.Combine(appData, "CloudPrint.Client", "logs");
+    }
+
+    public string LogDirectory { get; }
+
+    public void Write(AppLogEntry entry)
+    {
+        ArgumentNullException.ThrowIfNull(entry);
+        Directory.CreateDirectory(LogDirectory);
+
+        var logPath = Path.Combine(LogDirectory, $"cloudprint-{DateTime.Now:yyyyMMdd}.log");
+        lock (_syncRoot)
+        {
+            File.AppendAllText(logPath, Format(entry) + Environment.NewLine);
+        }
+    }
+
+    private static string Format(AppLogEntry entry)
+    {
+        var exceptionText = string.IsNullOrWhiteSpace(entry.ExceptionText)
+            ? string.Empty
+            : $" | Exception={entry.ExceptionText}";
+        return $"{entry.Timestamp:yyyy-MM-dd HH:mm:ss.fff} [{entry.LevelText}] {entry.Message}{exceptionText}";
+    }
+}