Fix UserAgent formatting

UserAgent should not be added after it already existed

API/MangaDownloadClients/HttpDownloadClient.cs

@@ -7,12 +7,14 @@ internal class HttpDownloadClient : DownloadClient
 {
     private static readonly HttpClient Client = new()
     {
-        Timeout = TimeSpan.FromSeconds(10)
+        Timeout = TimeSpan.FromSeconds(10),
+        DefaultVersionPolicy = HttpVersionPolicy.RequestVersionOrHigher
     };
 
     public HttpDownloadClient()
     {
-        Client.DefaultRequestHeaders.TryAddWithoutValidation("User-Agent", TrangaSettings.userAgent);
+        if(Client.DefaultRequestHeaders.UserAgent.Count < 1)
+            Client.DefaultRequestHeaders.UserAgent.ParseAdd(TrangaSettings.userAgent);
     }
     
     internal override RequestResult MakeRequestInternal(string url, string? referrer = null, string? clickButton = null)
@@ -20,25 +22,35 @@ internal class HttpDownloadClient : DownloadClient
         if (clickButton is not null)
             Log.Warn("Client can not click button");
         HttpResponseMessage? response = null;
-        while (response is null)
+        Uri uri = new(url);
+        HttpRequestMessage requestMessage = new(HttpMethod.Get, uri);
+        if (referrer is not null)
+            requestMessage.Headers.Referrer = new (referrer);
+        Log.Debug($"Requesting {url}");
+        try
         {
-            HttpRequestMessage requestMessage = new(HttpMethod.Get, url);
-            if (referrer is not null)
-                requestMessage.Headers.Referrer = new (referrer);
-            Log.Debug($"Requesting {url}");
-            try
-            {
-                response = Client.Send(requestMessage);
-            }
-            catch (HttpRequestException e)
-            {
-                Log.Error(e);
-                return new (HttpStatusCode.Unused, null, Stream.Null);
-            }
+            response = Client.Send(requestMessage);
+        }
+        catch (HttpRequestException e)
+        {
+            Log.Error(e);
+            return new (HttpStatusCode.Unused, null, Stream.Null);
         }
 
         if (!response.IsSuccessStatusCode)
         {
+            Log.Debug($"Request returned status code {(int)response.StatusCode} {response.StatusCode}:\n" +
+                      $"=====\n" +
+                      $"Request:\n" +
+                      $"{requestMessage.Method} {requestMessage.RequestUri}\n" +
+                      $"{requestMessage.Version} {requestMessage.VersionPolicy}\n" +
+                      $"Headers:\n\t{string.Join("\n\t", requestMessage.Headers.Select(h => $"{h.Key}: <{string.Join(">, <", h.Value)}"))}>\n" +
+                      $"{requestMessage.Content?.ReadAsStringAsync().Result}" +
+                      $"=====\n" +
+                      $"Response:\n" +
+                      $"{response.Version}\n" +
+                      $"Headers:\n\t{string.Join("\n\t", response.Headers.Select(h => $"{h.Key}: <{string.Join(">, <", h.Value)}"))}>\n" +
+                      $"{response.Content.ReadAsStringAsync().Result}");
             return new (response.StatusCode,  null, Stream.Null);
         }
 
@@ -64,7 +76,7 @@ internal class HttpDownloadClient : DownloadClient
         }
 
         // Request has been redirected to another page. For example, it redirects directly to the results when there is only 1 result
-        if (response.RequestMessage is not null && response.RequestMessage.RequestUri is not null)
+        if (response.RequestMessage is not null && response.RequestMessage.RequestUri is not null && response.RequestMessage.RequestUri != uri)
         {
             return new (response.StatusCode, document, stream, true, response.RequestMessage.RequestUri.AbsoluteUri);
         }

API/TrangaSettings.cs

@@ -11,7 +11,7 @@ public static class TrangaSettings
     public static string downloadLocation { get; private set; } = (RuntimeInformation.IsOSPlatform(OSPlatform.Linux) ? "/Manga" : Path.Join(Directory.GetCurrentDirectory(), "Downloads"));
     public static string workingDirectory { get; private set; } = Path.Join(RuntimeInformation.IsOSPlatform(OSPlatform.Linux) ? "/usr/share" : Environment.GetFolderPath(Environment.SpecialFolder.ApplicationData), "tranga-api");
     [JsonIgnore]
-    internal static readonly string DefaultUserAgent = $"Tranga ({Enum.GetName(Environment.OSVersion.Platform)}; {(Environment.Is64BitOperatingSystem ? "x64" : "")}) / 2.0";
+    internal static readonly string DefaultUserAgent = $"Tranga/2.0 ({Enum.GetName(Environment.OSVersion.Platform)}; {(Environment.Is64BitOperatingSystem ? "x64" : "")})";
     public static string userAgent { get; private set; } = DefaultUserAgent;
     public static int compression{ get; private set; } = 40;
     public static bool bwImages { get; private set; } = false;