/// <summary>
/// Deletes the proveded conversion method, but does not touch the source and target units
/// </summary>
/// <param name="entity"></param>
/// <returns></returns>
public bool DeleteConversionMethod(ConversionMethod entity)
{
Contract.Requires(entity != null, "provided unit can not be null");
Contract.Requires(entity.Id >= 0, "Id can not be empty");
using (IUnitOfWork uow = this.GetUnitOfWork())
{
IRepository<ConversionMethod> repoCM = uow.GetRepository<ConversionMethod>();
entity = repoCM.Reload(entity);
// remove all associations
entity.Source = null;
entity.Target = null;
//delete the entity
repoCM.Delete(entity);
// commit changes
uow.Commit();
}
// if any problem was detected during the commit, an exception will be thrown!
return (true);
}
public ConversionMethod UpdateConversionMethod(ConversionMethod entity)
{
Contract.Requires(entity != null, "provided entity can not be null");
Contract.Requires(entity.Id >= 0, "provided entity must have a permant ID");
Contract.Ensures(Contract.Result<ConversionMethod>() != null && Contract.Result<ConversionMethod>().Id >= 0, "No entity is persisted!");
using (IUnitOfWork uow = this.GetUnitOfWork())
{
IRepository<ConversionMethod> repoCM = uow.GetRepository<ConversionMethod>();
repoCM.Put(entity); // Merge is required here!!!!
uow.Commit();
}
return (entity);
}
/// <summary>
/// if there is no conversion method between source and target units, creates one otherwise fails
/// </summary>
/// <param name="description"></param>
/// <param name="formula"></param>
/// <param name="source"></param>
/// <param name="target"></param>
/// <returns></returns>
public ConversionMethod CreateConversionMethod(string formula, string description, Unit source, Unit target)
{
Contract.Requires(!string.IsNullOrWhiteSpace(formula), "formula can not be empty");
Contract.Requires(formula.Contains("s"), "Formula must use \'s\' as the representative for the source unit");
Contract.Requires(source != null, "source unit can not be null");
Contract.Requires(source.Id >= 0, "source unit must be persisted before this call");
Contract.Requires(target != null, "target unit can not be null");
Contract.Requires(target.Id >= 0, "target unit must be persisted before this call");
Contract.Ensures(Contract.Result<ConversionMethod>() != null && Contract.Result<ConversionMethod>().Id >= 0, "No Conversion Method persisted!");
ConversionMethod cm = new ConversionMethod()
{
Formula = formula,
Description = description,
Source = source,
Target = target,
};
source.ConversionsIamTheSource.Add(cm);
target.ConversionsIamTheTarget.Add(cm);
using (IUnitOfWork uow = this.GetUnitOfWork())
{
IRepository<ConversionMethod> repoCM = uow.GetRepository<ConversionMethod>();
ConversionMethod temp = repoCM.Get(c => c.Source.Id == source.Id && c.Target.Id == target.Id).FirstOrDefault(); // change it to Count instead of Get
if (temp != null)
throw new Exception(string.Format("There is already a conversion method between {0} and {1} having [{2}] formula", cm.Source.Name, cm.Target.Name, cm.Formula));
repoCM.Put(cm);
uow.Commit();
}
return (cm);
}
