/// <summary>
/// Invert the all of the paths in an expandToken, such that they are now in the same order as they are present in the
/// base url
/// </summary>
/// <param name="treeToInvert">the tree to invert paths on</param>
/// <returns>a new tree with all of its paths inverted</returns>
public ExpandToken NormalizePaths(ExpandToken treeToInvert)
{
// iterate through each expand term token, and reverse the tree in its path property
List <ExpandTermToken> updatedTerms = new List <ExpandTermToken>();
foreach (ExpandTermToken term in treeToInvert.ExpandTerms)
{
PathReverser pathReverser = new PathReverser();
PathSegmentToken reversedPath = term.PathToNavProp.Accept(pathReverser);
// we also need to call the select token normalizer for this level to reverse the select paths
SelectToken newSelectToken = term.SelectOption;
if (term.SelectOption != null)
{
SelectTreeNormalizer selectTreeNormalizer = new SelectTreeNormalizer();
newSelectToken = selectTreeNormalizer.NormalizeSelectTree(term.SelectOption);
}
ExpandToken subExpandTree;
if (term.ExpandOption != null)
{
subExpandTree = this.NormalizePaths(term.ExpandOption);
}
else
{
subExpandTree = null;
}
ExpandTermToken newTerm = new ExpandTermToken(reversedPath, term.FilterOption, term.OrderByOptions, term.TopOption, term.SkipOption, term.CountQueryOption, term.LevelsOption, term.SearchOption, newSelectToken, subExpandTree);
updatedTerms.Add(newTerm);
}
return(new ExpandToken(updatedTerms));
}
/// <summary>
/// Normalize a SelectToken into something that can be used to trim an expand tree.
/// </summary>
/// <param name="treeToNormalize">The select token to normalize</param>
/// <returns>Normalized SelectToken</returns>
public SelectToken NormalizeSelectTree(SelectToken treeToNormalize)
{
PathReverser pathReverser = new PathReverser();
List <PathSegmentToken> invertedPaths = (from property in treeToNormalize.Properties
select property.Accept(pathReverser)).ToList();
// to normalize a select token we just need to invert its paths, so that
// we match the ordering on an ExpandToken.
return(new SelectToken(invertedPaths));
}
/// <summary>
/// Build the next level PathReverser
/// </summary>
/// <param name="nextLevelToken">the next level token</param>
/// <param name="nextChildToken">the next levels child token</param>
/// <returns>the path token from the next level.</returns>
private static PathSegmentToken BuildNextStep(PathSegmentToken nextLevelToken, PathSegmentToken nextChildToken)
{
PathReverser nextStepReverser = new PathReverser(nextChildToken);
return(nextLevelToken.Accept(nextStepReverser));
}