public async Task <Exercise> Add(string name, string description)
{
if (string.IsNullOrWhiteSpace(name))
{
throw new ArgumentNullException(name);
}
if (string.IsNullOrWhiteSpace(description))
{
throw new ArgumentNullException(description);
}
var exercise = await Get(name);
if (exercise != null)
{
throw new EntityExistsException($"Exercise with name {name} already exists.");
}
exercise = new Exercise
{
Name = name,
Description = description
};
_context.Exercises.Add(exercise);
await _context.SaveChangesAsync();
return(exercise);
}