public IHttpActionResult Get(int id)
{
//MethodSummary: get object, compare and return diff
DiffObject diffObject;
//if Left or Right properties were not set return not found
if (!_diffObjectRepository.TryGet(id, out diffObject) || diffObject.Left == null || diffObject.Right == null)
{
return(NotFound());
}
ObjectDiff objectDiff = _differ.GetDiff(diffObject.Left, diffObject.Right);
return(Ok(objectDiff));
}
/// <summary>
/// Gets the difference.
/// </summary>
/// <returns>ObjectDiff representing difference between left and right</returns>
public ObjectDiff GetDiff(byte[] left, byte[] right)
{
//edge case left is null or empty
if (left == null || left.Length == 0)
{
if (right == null || right.Length == 0)
{
return(new ObjectDiff {
diffResultType = DiffResultType.Equals
});
}
return(new ObjectDiff {
diffResultType = DiffResultType.SizeDoNotMatch
});
}
//edge case right is null or empty but left is not empty
if (right == null || right.Length == 0)
{
return(new ObjectDiff {
diffResultType = DiffResultType.SizeDoNotMatch
});
}
//both left and right has lenghth > 0, test if lengthes are equal
if (left.Length != right.Length)
{
return(new ObjectDiff {
diffResultType = DiffResultType.SizeDoNotMatch
});
}
//left and right has equal length, compare content
List <ContentDiff> contentDiffs = new List <ContentDiff>();
int offset = 0;
int length = 0;
//scan through to find all diff sequences
for (int i = 0; i < left.Length; i++)
{
if (left[i] != right[i])
{
//test if it is a beginning of new diff sequence
if (length == 0)
{
//mark where it starts
offset = i;
}
//increase the diff length
length++;
}
else if (length > 0) //test if diff sequence ends here
{
//report new diff sequence
contentDiffs.Add(new ContentDiff
{
offset = offset,
length = length
});
//reset diff length
length = 0;
}
}
//every byte different
if (length > 0)
{
contentDiffs.Add(new ContentDiff
{
offset = offset,
length = length
});
}
ObjectDiff objectDiff = new ObjectDiff
{
diffResultType = DiffResultType.Equals,
};
//if there were different sequences mark result as ContentDoNotMatch
if (contentDiffs.Count > 0)
{
objectDiff.diffResultType = DiffResultType.ContentDoNotMatch;
objectDiff.diffs = contentDiffs;
}
return(objectDiff);
}