public Task BindModelAsync(ModelBindingContext bindingContext)
{
if (bindingContext == null)
{
throw new ArgumentNullException(nameof(bindingContext));
}
var modelName = bindingContext.ModelName;
// Try to fetch the value of the argument by name
var valueProviderResult =
bindingContext.ValueProvider.GetValue(modelName);
if (valueProviderResult == ValueProviderResult.None)
{
bindingContext.Result = ModelBindingResult.Success(Enumerable.Empty <ISortParticle <TEntity> >());
return(Task.CompletedTask);
}
bindingContext.ModelState.SetModelValue(modelName, valueProviderResult);
var csvInput = valueProviderResult.FirstValue;
if (!PContext.TryParseCsv(
input: csvInput,
out IEnumerable <ISortParticle <TEntity> > particles
))
{
bindingContext.ModelState.TryAddModelError(modelName, "Could not parse provided sorts.");
return(Task.CompletedTask);
}
bindingContext.Result = ModelBindingResult.Success(particles);
return(Task.CompletedTask);
}
public bool TryGenerate(IPContext context, string input, out IFilterParticle <TEntity> particle)
{
input = input.Trim();
// Attempt to split the input by all "||" not enclosed in quotes or parenthesis.
Regex regex = new Regex("[||](?=(?:[^\"]*\"[^\"]*\")*(?![^\"]*\"))(?=(((?!\\)).)*\\()|[^\\(\\)]*$)");
var splitInput = regex
.Split(input)
.Where(x => !string.IsNullOrWhiteSpace(x));
// If we dont end up with at least two parts, there's no OR operation here.
if (splitInput.Count() < 2)
{
particle = null;
return(false);
}
var trimmedInputs = splitInput.Select(x => x.Trim());
// We parse each split input and OR it to the previous one.
IFilterParticle <TEntity> resultParticle = null;
foreach (var filter in trimmedInputs)
{
var cleanFilter = filter;
if (filter.StartsWith("(") && filter.EndsWith(")"))
{
cleanFilter = filter.Substring(1, filter.Length - 2);
}
if (!context.TryParseCsv(cleanFilter, out IEnumerable <IFilterParticle <TEntity> > particles))
{
particle = null;
return(false);
}
var partialResult = particles.Count() > 1 ?
new AndFilterParticle <TEntity>(particles.ToArray()) :
particles.Single();
resultParticle = resultParticle is null ?
partialResult :
new OrFilterParticle <TEntity>(resultParticle, partialResult);
}
particle = resultParticle;
return(true);
}