changed logging to allow debugging

Program.cs

@@ -4,6 +4,8 @@ using Cronos;
 using Renci.SshNet;
 using Renci.SshNet.Sftp;
 using Serilog;
+using Serilog.Core;
+using Serilog.Events;
 
 var resetEvent = new ManualResetEvent(false);
 using var tokenSource = new CancellationTokenSource();
@@ -30,14 +32,27 @@ return;
 
 static void SetupLogging()
 {
+    var minLevel = (Environment.GetEnvironmentVariable("LOG_LEVEL") ?? "info").ToUpperInvariant() switch
+    {
+        "VERBOSE" => LogEventLevel.Verbose,
+        "DEBUG" => LogEventLevel.Debug,
+        "WARNING" => LogEventLevel.Warning,
+        "ERROR" => LogEventLevel.Error,
+        "FATAL" => LogEventLevel.Fatal,
+        _ => LogEventLevel.Information
+    };
+    var levelSwitch =  new LoggingLevelSwitch(minLevel);
+    
     Log.Logger = new LoggerConfiguration()
-        .MinimumLevel.Information()
+        .MinimumLevel.ControlledBy(levelSwitch)
         .WriteTo.Console()
         .WriteTo.File("log.txt",
             rollingInterval: RollingInterval.Day, 
             rollOnFileSizeLimit: true,
             retainedFileCountLimit: 10)
         .CreateLogger();
+    
+    Log.Debug($"Logging initialized at {minLevel}");
 }
 
 static Config LoadConfig()
@@ -92,9 +107,12 @@ static async Task ScheduleJobs(Config config, CancellationToken token)
 static async Task RunJob(Config config, CancellationToken token)
 {
     using var client = GetClient(config.FTP);
+    Log.Information($"Connecting to {config.FTP.Host}:{config.FTP.Port} as {config.FTP.UserName}");
+    
     var buffer = Math.Clamp(config.BufferSizeMB ?? 1, 0.5f, 4);
     client.BufferSize = (uint)(1024 * 1024 * buffer);
-    Log.Information($"Connecting to {config.FTP.Host}:{config.FTP.Port} as {config.FTP.UserName}");
+    Log.Debug($"Connection buffer size: {client.BufferSize}");
+    
     await client.ConnectAsync(token);
     foreach (var target in config.Targets)
     {