/// <summary>
/// Updates a material found by id to match newMaterial. Will validate all the data passed. Expects a full
/// Material object to update by. Fields that are to remain the same, should still be passed holding the
/// original value.
/// </summary>
/// <param name="id">The ID of the material</param>
/// <param name="newMaterial">The new data wrapped in a Material object</param>
/// <returns>The number of rows that were changed</returns>
///
/// <exception cref="ArgumentNullException">
/// If any of the Isbn, Title, Language or Description properties
/// are null or empty
/// </exception>
///
/// <exception cref="ArgumentException">
/// If MaterialType, any of MaterialSubjects or any of MaterialAuthors can't
/// be found in the database
/// </exception>
///
/// <remarks>NOT TESTED</remarks>
public int Update(int id, Material newMaterial)
{
var material = FindByID(id);
if (material == null)
{
return(0);
}
// validate material data
if (newMaterial.Isbn.IsNullOrEmpty())
{
throw new ArgumentNullException(nameof(newMaterial.Isbn), "ISBN can't be null or empty");
}
if (newMaterial.Title.IsNullOrEmpty())
{
throw new ArgumentNullException(nameof(newMaterial.Title), "Title can't be null or empty");
}
if (newMaterial.Language.IsNullOrEmpty())
{
throw new ArgumentNullException(nameof(newMaterial.Language), "Language can't be null or empty");
}
if (newMaterial.Description.IsNullOrEmpty())
{
throw new ArgumentNullException(nameof(newMaterial.Description), "Description can't be null or empty");
}
var materialType = _context.MaterialTypes.Find(newMaterial.Type.TypeId);
if (materialType == null)
{
throw new ArgumentException("MaterialType must already exist", nameof(newMaterial.Type));
}
material.Isbn = newMaterial.Isbn;
material.Title = newMaterial.Title;
material.Language = newMaterial.Language;
material.Lendable = newMaterial.Lendable;
material.Description = newMaterial.Description;
material.Type = materialType;
var materialSubjects = newMaterial.MaterialSubjects
.Select(ms =>
{
var subject = ms.MaterialSubject;
var fetchedSubject = _context.MaterialSubjects.Find(subject.SubjectId);
if (fetchedSubject == null)
{
throw new ArgumentException("MaterialSubjects must already exist", nameof(newMaterial.MaterialSubjects));
}
return(new MaterialSubjects {
MaterialSubject = fetchedSubject, Material = material
});
}).ToList();
var materialAuthors = newMaterial.MaterialAuthors
.Select(ma =>
{
var author = ma.Author;
var fetchedAuthor = _authorController.FindByID(author.AuthorId);
if (fetchedAuthor == null)
{
if (author.FirstName.IsNullOrEmpty() || author.LastName.IsNullOrEmpty())
{
throw new ArgumentNullException(
nameof(newMaterial.MaterialAuthors),
"New authors must be provided with FirstName AND LastName"
);
}
var newAuthor = _authorController.Create(author.FirstName, author.LastName);
_authorController.Insert(newAuthor);
return(new MaterialAuthor {
Author = newAuthor, Material = material
});
}
return(new MaterialAuthor {
Author = fetchedAuthor, Material = material
});
}).ToList();
// remove previous material subjects
_context.RemoveRange(material.MaterialSubjects);
material.MaterialSubjects = materialSubjects;
// remove pre-existing authors
_context.RemoveRange(material.MaterialAuthors);
material.MaterialAuthors = materialAuthors;
return(_context.SaveChanges());
}