private static string SerializeColumnToString <T>(T column)
{
if (column == null)
{
return("null");
}
var columnType = column.GetType();
var result = new StringBuilder();
if (EntityTypeDescriptor.IsSimpleType(columnType) || EntityTypeDescriptor.IsNullableType(columnType))
{
result.Append(column);
}
else if (EntityTypeDescriptor.IsSupportedEnumerable(columnType))
{
var enumerable = column as IEnumerable;
foreach (var item in enumerable)
{
result.AppendFormat("{0},", SerializeColumnToString(item));
}
}
else
{
var typeDescription = EntityTypeDescriptor.GetTypeDescription(columnType);
foreach (var item in typeDescription.Columns)
{
result.AppendFormat("{0}={1}\n", item.ColumnAttribute.Name ?? item.ColumnInfo.Name,
SerializeColumnToString(item.ColumnInfo.GetValue(column, null)));
}
}
return(result.ToString());
}
private static object ConvertValue(object value, Type columnType)
{
if (value == null)
{
return(null);
}
if (columnType.IsEnum)
{
return(Enum.Parse(columnType, value.ToString()));
}
if (columnType == typeof(DateTime))
{
return(DateTime.Parse(value.ToString()));
}
if (columnType == typeof(DateTimeOffset))
{
return(DateTimeOffset.Parse(value.ToString()));
}
if (EntityTypeDescriptor.IsNullableType(columnType))
{
return(Convert.ChangeType(value, Nullable.GetUnderlyingType(columnType)));
}
return(Convert.ChangeType(value, columnType));
}
private static void AppendPrimaryKey <TEntity>(TEntity entity, NodeReference node)
{
var typeDescription = EntityTypeDescriptor.GetTypeDescription(entity.GetType());
var identityKeys = typeDescription.IdentityKeys;
if (identityKeys.Any())
{
//according to the validation rules
var identityKey = identityKeys.Single();
var newSeed = IncrementIdentity(node);
var propertyType = identityKey.ColumnInfo.PropertyType;
propertyType = !EntityTypeDescriptor.IsNullableType(propertyType)
? propertyType
: Nullable.GetUnderlyingType(propertyType);
var correctValue = Convert.ChangeType(newSeed, propertyType);
identityKey.ColumnInfo.SetValue(entity, correctValue, null);
node.AppendSubscript(newSeed);
}
else
{
var hash = PrimaryKeyCalculator.GetPrimaryKey(entity);
if (IsKeyExists(hash, node))
{
throw new GlobalsDbException("Violation of Primary Key constraint. Cannot insert duplicate key");
}
node.SetSubscriptCount(0);
node.AppendSubscript(hash);
}
}
private static void WriteComplexEntity <TEntity>(TEntity entity, NodeReference node)
{
if (entity == null)
{
return;
}
var entityType = entity.GetType();
var underlyingType = EntityTypeDescriptor.IsNullableType(entityType)
? Nullable.GetUnderlyingType(entityType)
: entityType;
var columns = EntityTypeDescriptor.GetTypeDescription(underlyingType).Columns;
foreach (var column in columns)
{
node.AppendSubscript(column.ColumnAttribute.Name ?? column.ColumnInfo.Name);
if (column.IsSimpleColumn)
{
var value = column.ColumnInfo.GetValue(entity, null);
if (value != null)
{
if (column.IsNullableColumn)
{
node.Set(value != null ? value.ToString() : null);
}
else
{
node.Set(value.ToString());
}
}
}
else if (column.IsArrayColumn)
{
var array = column.ColumnInfo.GetValue(entity, null) as Array;
WriteArray(node, array);
}
else if (column.IsEnumerableColumn)
{
var items = column.ColumnInfo.GetValue(entity, null) as IEnumerable;
if (items != null)
{
WriteEnumerable(node, items);
}
}
else
{
WriteComplexEntity(column.ColumnInfo.GetValue(entity, null), node);
}
node.SetSubscriptCount(node.GetSubscriptCount() - 1);
}
}
private static object ReadComplexNode(NodeReference node, Type objectType)
{
var isNullable = EntityTypeDescriptor.IsNullableType(objectType);
if (isNullable && IsNullableComplexColumnEmpty(node))
{
return(null);
}
var underlyingType = !isNullable
? objectType
: Nullable.GetUnderlyingType(objectType);
var typeDescription = EntityTypeDescriptor.GetTypeDescription(underlyingType);
var instance = InstanceCreator.CreateInstance(underlyingType);
foreach (var column in typeDescription.Columns)
{
var subscript = column.ColumnAttribute.Name ?? column.ColumnInfo.Name;
if (column.IsSimpleColumn)
{
node.AppendSubscript(subscript);
var nodeValue = node.GetObject();
column.ColumnInfo.SetValue(instance, ConvertValue(nodeValue, column.ColumnInfo.PropertyType), null);
}
else if (column.IsArrayColumn)
{
node.AppendSubscript(subscript);
column.ColumnInfo.SetValue(instance, ReadArray(node, column.ColumnInfo.PropertyType), null);
}
else if (column.IsEnumerableColumn)
{
node.AppendSubscript(subscript);
column.ColumnInfo.SetValue(instance, ReadEnumerable(node, column.ColumnInfo.PropertyType), null);
}
else if (column.IsComplexColumn)
{
node.AppendSubscript(subscript);
column.ColumnInfo.SetValue(instance,
ReadComplexNode(node, column.ColumnInfo.PropertyType), null);
}
node.SetSubscriptCount(node.GetSubscriptCount() - 1);
}
return(instance);
}
private static object PerformBinaryOperation(object left, Type leftDataType, object right,
Type rightDataType, ExpressionType nodeType)
{
var leftNode = left as NodeReference;
var rightNode = right as NodeReference;
var leftData = (leftNode == null) ? left : DatabaseManager.ReadNode(leftNode, leftDataType);
var rightData = (rightNode == null) ? right : DatabaseManager.ReadNode(rightNode, rightDataType);
if ((EntityTypeDescriptor.IsNullableType(leftDataType) || EntityTypeDescriptor.IsNullableType(rightDataType)) &&
(leftData == null || rightData == null))
{
return(ResolveNullableOperation(leftData, rightData, nodeType));
}
return(BinaryOperationHandler[nodeType](leftData, rightData));
}
private static Type ResolveParameterType(Type type, Type parentType)
{
if (EntityTypeDescriptor.IsNullableType(type))
{
return(type);
}
if (type == typeof(IQueryable))
{
return(parentType.GetGenericArguments().First());
}
var genericArguments = type.GetGenericArguments();
if (genericArguments.Length == 1)
{
return(genericArguments.Single());
}
return(type);
}
private static object ResolveColumn(ColumnAttribute columnAttribute, MemberExpression expression, IEnumerable <NodeReference> references)
{
if (columnAttribute != null)
{
foreach (var nodeReference in references)
{
nodeReference.AppendSubscript(columnAttribute.Name ?? expression.Member.Name);
}
return(references);
}
if (EntityTypeDescriptor.IsSupportedEnumerable(expression.Expression.Type) && expression.Member.Name == "Count")
{
var result = references.Select(DatabaseManager.GetEnumerableCount).ToList();
return(result);
}
if (EntityTypeDescriptor.IsArrayType(expression.Expression.Type) && expression.Member.Name == "Length")
{
var result = references.Select(DatabaseManager.GetEnumerableCount).ToList();
return(result);
}
if (EntityTypeDescriptor.IsArrayType(expression.Expression.Type) && expression.Member.Name == "LongLength")
{
var result = references.Select(DatabaseManager.GetEnumerableCount).ToList();
return(result);
}
if (EntityTypeDescriptor.IsNullableType(expression.Expression.Type) && expression.Member.Name == "Value")
{
return(references);
}
var parentType = expression.Expression.Type;
var data = DatabaseManager.ReadNodes(references, parentType) as IEnumerable;
return(ProcessLoadedEntityMembers(data, expression));
}
internal static object GetDefaultValue(Type instanceType)
{
return(((!instanceType.IsValueType) || (EntityTypeDescriptor.IsNullableType(instanceType)))
? null
: CreateInstance(instanceType));
}
