/// <summary>
/// Applies the PATH operation to the given Document.
/// </summary>
/// <param name="operation">The PATCH operation.</param>
/// <param name="document">The Document.</param>
/// <exception cref="System.ArgumentNullException"></exception>
public static void Apply(this PatchOperationDto operation, Document document)
{
operation.Validate();
if (document == null)
throw new ArgumentNullException(nameof(document));
var dictionary = document.AsDictionary();
var path = new JsonPath(operation.path);
operation.Apply(dictionary, path);
}
private static void Apply(this PatchOperationDto operation, object parentObject, JsonPath path)
{
if (parentObject == null)
throw new ArgumentNullException(nameof(parentObject));
if (path == null)
throw new ArgumentNullException(nameof(path));
if (path.Segments.Count < 1)
throw new ArgumentException($"Invalid path: '{path}'");
var currentSegment = path.Segments[0];
if (parentObject is IList)
{
var array = parentObject as IList;
var index = currentSegment.ToArrayIndex(array);
if (path.HasNext())
{
// We're not yet on the target location, continue traversing the path.
var nextPath = path.GetNext();
object childObject = index < array.Count ? array[index] : null;
operation.Apply(childObject, nextPath);
}
else
{
// We are on the target location, perform the operation.
switch (operation.op)
{
case PatchOpCode.ADD:
array.Insert(index, operation.value);
break;
case PatchOpCode.REPLACE:
array[index] = operation.value;
break;
case PatchOpCode.REMOVE:
array.RemoveAt(index);
break;
}
}
}
else if (parentObject is IDictionary<string, object>)
{
var dictionary = parentObject as IDictionary<string, object>;
var fieldName = currentSegment;
if (path.HasNext())
{
// We're not yet on the target location, continue traversing the path.
var nextPath = path.GetNext();
object childObject = dictionary.ContainsKey(fieldName) ? dictionary[fieldName] : null;
operation.Apply(childObject, nextPath);
}
else
{
// We are on the target location, perform the operation.
switch (operation.op)
{
case PatchOpCode.ADD:
case PatchOpCode.REPLACE:
dictionary[fieldName] = operation.value;
break;
case PatchOpCode.REMOVE:
dictionary.Remove(fieldName);
break;
}
}
}
}
