/// <summary>
/// Default constructor
/// </summary>
/// <param name="table">The main table</param>
/// <param name="principleKeyColumn">The principle key column of the <see cref="Table"/></param>
/// <param name="referencedTable">The referenced table</param>
/// <param name="foreignKeyColumn">The foreign key column of the <see cref="ReferencedTable"/></param>
/// <param name="index">
/// The index level of the join.
/// NOTE: If the index is set to zero, then the <see cref="Table"/> is the root table!
/// </param>
/// <param name="isRightJoin">
/// A flag indicating whether we have a foreign key to primary key join (right join) or not.
/// NOTE: When this is set to <see cref="false"/> a left join is applied (the navigation property of the root type is an <see cref="IEnumerable{T}"/>)!
/// NOTE: When this is set to <see cref="true"/> a right join is applied (the navigation property of the root type is an object)!
/// </param>
public JoinMap(IDbProviderTable table, IDbProviderColumn principleKeyColumn, IDbProviderTable referencedTable, IDbProviderColumn foreignKeyColumn, int index, bool isRightJoin) : base()
{
Table = table ?? throw new ArgumentNullException(nameof(table));
PrincipleKeyColumn = principleKeyColumn ?? throw new ArgumentNullException(nameof(principleKeyColumn));
ReferencedTable = referencedTable ?? throw new ArgumentNullException(nameof(referencedTable));
ForeignKeyColumn = foreignKeyColumn ?? throw new ArgumentNullException(nameof(foreignKeyColumn));
Index = index;
IsRightJoin = isRightJoin;
}
/// <summary>
/// Performs the required includes on the specified <paramref name="queryable"/>
/// </summary>
/// <param name="queryable">The queryable</param>
/// <param name="initialTable">The initial table</param>
/// <returns></returns>
private IQueryable PerformIncludes(IQueryable queryable, IDbProviderTable initialTable)
{
// For every join...
foreach (var join in Joins)
{
var joinsPath = ComputePath(join);
// For every related join...
foreach (var j in joinsPath)
{
// Get the type of the model
var modelType = queryable.GetType().GetGenericArguments()[0];
// If it's the first join...
if (joinsPath.ElementAt(0) == j)
{
// Get the navigation property name
var navigationPropertyName = CeidDiplomatikiHelpers.GetPluralForm(j.ReferencedTable.TableName);
// Get the navigation property
var navigationProperty = modelType.GetProperty(navigationPropertyName);
// Create the expression
var expression = ExpressionHelpers.CreatePropertySelectorExpression(modelType, navigationProperty);
// Get the Include<TEntity, TProperty> method
var includeMethod = typeof(EntityFrameworkQueryableExtensions).GetMethods().First(x => x.Name == nameof(EntityFrameworkQueryableExtensions.Include) && x.GetParameters()[1].ParameterType != typeof(string));
// Set the generic arguments (TEntity and TProperty)
includeMethod = includeMethod.MakeGenericMethod(modelType, navigationProperty.PropertyType);
// Call the Include method
queryable = (IQueryable)includeMethod.Invoke(null, new object[] { queryable, expression });
// Continue
continue;
}
queryable = PerformThenInclude(queryable, j);
}
}
// Return the queryable
return(queryable);
}
