/// <summary>
/// Loads the refrence for the entity
/// return true if the entity reference changed
/// </summary>
/// <param name="entity"></param>
/// <param name="dbReference"></param>
/// <returns></returns>
private bool LoadDbMultiReference(IDbEntity entity, IList dbMultiRefs)
{
// if null
// do nothing
if (dbMultiRefs == null)
{
return(false);
}
bool changed = false;
for (int i = dbMultiRefs.Count - 1; i >= 0; i--)
{
IDbReference reference = (IDbReference)dbMultiRefs[i];
IDbEntity otherRef = FindEntity(reference.EntityType, reference.ReferenceId.Value);
// if other ref is null
// that means that the link between the entities is gone
// so delete from the list
if (otherRef == null)
{
dbMultiRefs.RemoveAt(i);
changed = true;
}
}
return(changed);
}
/// <summary>
/// Wire up the references of an entity
/// </summary>
/// <param name="entity"></param>
private void InjectSingleReferences(IDbEntity entity)
{
Type entityType = entity.GetType();
EntityInfo infos = GetEntityInfo(entityType);
bool changed = false;
// single refs
foreach (SingleReferenceProperty referenceProperty in infos.SingleReferenceInjectors)
{
IDbReference dbReference = (IDbReference)referenceProperty.PropertyAccessor.GetValue(entity);
if (LoadSingleDbReference(entityType, entity, dbReference))
{
changed = true;
}
}
// trigger if event is entity is changed
if (changed)
{
OnEntityChanged?.Invoke(entity);
}
}
/// <summary>
/// Remove entity from Db
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="t"></param>
public void Remove <T>(T t) where T : IDbEntity
{
AddType <T>();
Type type = typeof(T);
Database[type].Remove(t);
// check entity references
foreach (KeyValuePair <Type, HashSet <IDbEntity> > kv in Database)
{
Type entityType = kv.Key;
EntityInfo infos = GetEntityInfo(entityType);
foreach (IDbEntity entity in kv.Value)
{
bool changed = false;
// single refs
foreach (SingleReferenceProperty referenceProperty in infos.SingleReferenceInjectors)
{
IDbReference dbReference = (IDbReference)referenceProperty.PropertyAccessor.GetValue(entity);
if (dbReference.ReferenceId == t.EntityId && dbReference.EntityType == type)
{
dbReference.ReferenceId = null;
dbReference.Entity = null;
changed = true;
}
}
// multiple refs
foreach (MultipleReferenceProperty referenceProperty in infos.MultipleReferenceInjectors)
{
IList dbReference = (IList)referenceProperty.PropertyAccessor.GetValue(entity);
if (dbReference == null)
{
continue;
}
for (int i = dbReference.Count - 1; i >= 0; i--)
{
IDbReference reference = (IDbReference)dbReference[i];
if (reference.ReferenceId == t.EntityId && reference.EntityType == type)
{
dbReference.RemoveAt(i);
changed = true;
}
}
}
if (changed)
{
OnEntityChanged?.Invoke(entity);
}
}
}
OnDatabaseChanged?.Invoke(this);
OnEntityRemoved?.Invoke(t);
}
/// <summary>
/// Loads the refrence for the entity
/// return true if the entity reference changed
/// </summary>
/// <param name="entity"></param>
/// <param name="dbReference"></param>
/// <returns></returns>
private bool LoadSingleDbReference(Type entityType, IDbEntity entity, IDbReference dbReference)
{
// if null
// do nothing
if (dbReference == null)
{
return(false);
}
// if refrence id doesn't exist
// then set to null
if (!dbReference.ReferenceId.HasValue && dbReference.Entity != null)
{
dbReference.Entity = null;
return(true);
}
// else if id exists but instance isn't linked
// then inject the value from the db
else if (dbReference.ReferenceId.HasValue)
{
IDbEntity searchReference = null;
// if entity is null
// or if different id
// then load from db
if (dbReference.Entity == null || dbReference.Entity.EntityId != dbReference.ReferenceId)
{
searchReference = Database[dbReference.EntityType].FirstOrDefault(e => e.EntityId == dbReference.ReferenceId.Value);
if (searchReference == null)
{
dbReference.ReferenceId = null;
throw new Exception($"Entity doesn't exist ( type : { dbReference.EntityType.Name } , id : { dbReference.ReferenceId.Value } )");
}
}
else
{
searchReference = dbReference.Entity;
}
List <MultipleReferenceProperty> otherMultiRef = EntityInfos[dbReference.EntityType].MultipleReferenceInjectors.Where(i => i.ReferenceType == entityType).ToList();
if (otherMultiRef != null)
{
foreach (MultipleReferenceProperty mutli in otherMultiRef)
{
IList multiRefList = (IList)mutli.PropertyAccessor.GetValue(searchReference);
// if the multi list doesn't already contain a reference to the current entity
// add a new reference to the list
if (multiRefList.Cast <IDbReference>().FirstOrDefault(r => r.ReferenceId == entity.EntityId) == null)
{
IDbReference reference = mutli.ReferenceCreator();
reference.Entity = entity;
reference.ReferenceId = entity.EntityId;
multiRefList.Add(reference);
}
}
}
List <SingleReferenceProperty> otherSingleRef = EntityInfos[dbReference.EntityType].SingleReferenceInjectors.Where(i => i.ReferenceType == entityType).ToList();
if (otherSingleRef != null)
{
foreach (SingleReferenceProperty single in otherSingleRef)
{
IDbReference singleReference = (IDbReference)single.PropertyAccessor.GetValue(searchReference);
if (singleReference.ReferenceId != entity.EntityId)
{
singleReference.Entity = entity;
singleReference.ReferenceId = entity.EntityId;
}
}
}
dbReference.Entity = searchReference;
return(true);
}
return(false);
}