Add support to download public node (retrieved with GetNodeFromLink) with Download(INode) method (#196)

* #195 Add support to download public node (retrieved with GetNodeFromLink) with Download(INode) method

* Use proper DownloadRequest for public nodes created by GetNodesFromLink

Author: gpailler

MegaApiClient.Tests/Data/SampleZipFile.zip

@@ -191,15 +191,28 @@ public static IEnumerable<object[]> DownloadLinkToFileInvalidParameter
       }
     }
 
-    [Fact]
-    public void DownloadLink_ToFile_Succeeds()
+    [Theory]
+    [JsonInputsDataAttribute(new object[] { "Data/SampleZipFile.zip" }, new[] { "ZipFileLink" })]
+    [JsonInputsDataAttribute(new object[] { "Data/SampleFile.jpg" }, new[] { "FileLink" })]
+    public void DownloadLink_ToFile_Succeeds(string resultFile, string uri)
     {
-      const string ExpectedResultFile = "Data/SampleFile.jpg";
+      var outFile = GetTempFileName();
+      Context.Client.DownloadFile(new Uri(uri), outFile);
+
+      Assert.Equal(File.ReadAllBytes(GetAbsoluteFilePath(resultFile)), File.ReadAllBytes(outFile));
+    }
+
+    [Theory]
+    [JsonInputsDataAttribute(new object[] { "Data/SampleZipFile.zip" }, new[] { "ZipFileLink" })]
+    [JsonInputsDataAttribute(new object[] { "Data/SampleFile.jpg" }, new[] { "FileLink" })]
+    public void GetNodeFromLink_And_Download_ToFile_Succeeds(string resultFile, string uri)
+    {
+      var node = Context.Client.GetNodeFromLink(new Uri(uri));
 
       var outFile = GetTempFileName();
-      Context.Client.DownloadFile(new Uri(AuthenticatedTestContext.Inputs.FileLink), outFile);
+      Context.Client.DownloadFile(node, outFile);
 
-      Assert.Equal(File.ReadAllBytes(GetAbsoluteFilePath(ExpectedResultFile)), File.ReadAllBytes(outFile));
+      Assert.Equal(File.ReadAllBytes(GetAbsoluteFilePath(resultFile)), File.ReadAllBytes(outFile));
     }
 
     [Fact]

MegaApiClient.Tests/DownloadUpload.cs

@@ -596,7 +596,7 @@ public Stream Download(INode node, CancellationToken? cancellationToken = null)
       EnsureLoggedIn();
 
       // Retrieve download URL
-      var downloadRequest = new DownloadUrlRequest(node);
+      var downloadRequest = node is PublicNode publicNode && publicNode.ParentId == null ? (RequestBase)new DownloadUrlRequestFromId(node.Id) : new DownloadUrlRequest(node);
       var downloadResponse = Request<DownloadUrlResponse>(downloadRequest);
 
       Stream dataStream = new BufferedStream(_webClient.GetRequestRaw(new Uri(downloadResponse.Url)));
@@ -665,13 +665,13 @@ public INode GetNodeFromLink(Uri uri)
 
       EnsureLoggedIn();
 
-      GetPartsFromUri(uri, out var id, out _, out _, out var key);
+      GetPartsFromUri(uri, out var id, out var iv, out var metaMac, out var key);
 
       // Retrieve attributes
       var downloadRequest = new DownloadUrlRequestFromId(id);
       var downloadResponse = Request<DownloadUrlResponse>(downloadRequest);
 
-      return new Node(id, downloadResponse, key);
+      return new PublicNode(new Node(id, downloadResponse, key, iv, metaMac), null);
     }
 
     /// <summary>

MegaApiClient/MegaApiClient.cs

@@ -24,13 +24,16 @@ public Node(byte[] masterKey, ref List<SharedKey> sharedKeys)
       _sharedKeys = sharedKeys;
     }
 
-    internal Node(string id, DownloadUrlResponse downloadResponse, byte[] key)
+    internal Node(string id, DownloadUrlResponse downloadResponse, byte[] key, byte[] iv, byte[] metaMac)
     {
       Id = id;
       Attributes = Crypto.DecryptAttributes(downloadResponse.SerializedAttributes.FromBase64(), key);
       Size = downloadResponse.Size;
       Type = NodeType.File;
       FileAttributes = DeserializeFileAttributes(downloadResponse.SerializedFileAttributes);
+      Key = key;
+      Iv = iv;
+      MetaMac = metaMac;
     }
 
     #region Public properties
@@ -271,9 +274,16 @@ private bool IsShareRoot
     {
       get
       {
-        var serializedKey = _node.SerializedKey.Split('/')[0];
-        var splitPosition = serializedKey.IndexOf(":", StringComparison.Ordinal);
-        return serializedKey.Substring(0, splitPosition) == Id;
+        if (_node.SerializedKey == null)
+        {
+          return true;
+        }
+        else
+        {
+          var serializedKey = _node.SerializedKey.Split('/')[0];
+          var splitPosition = serializedKey.IndexOf(":", StringComparison.Ordinal);
+          return serializedKey.Substring(0, splitPosition) == Id;
+        }
       }
     }
   }