/// <summary>
/// Returns a function that convert a SQLite row into an instance of type T using the provided builder functions. The builder
/// function may return the same instane of builder more than once, provided that the instance is thread local or locked such
/// that only a single given thread ever has access to the instance between calls to builder and build.
/// </summary>
/// <returns>The result selector function.</returns>
/// <param name="builder">A function that provides a builder object that can be used to build an instance of T.</param>
/// <param name="build">A function that builds and instance of T using the builder.</param>
/// <typeparam name="TBuilder">The builder type.</typeparam>
/// <typeparam name="T">The mapped type.</typeparam>
public static Func <IReadOnlyList <IResultSetValue>, T> RowToObject <TBuilder, T>(Func <TBuilder> builder, Func <TBuilder, T> build)
{
Contract.Requires(builder != null);
Contract.Requires(build != null);
var columns = new Dictionary <string, PropertyInfo>();
var tableName = TableMapping.Get <T>().TableName;
var typ = typeof(TBuilder);
var props = typ.GetNotIgnoredSettableProperties();
foreach (var prop in props)
{
var columnName = prop.GetColumnName();
columns.Add(columnName, prop);
}
return((IReadOnlyList <IResultSetValue> row) =>
{
var builderInst = builder();
foreach (var column in row)
{
var columnInfo = column.ColumnInfo;
PropertyInfo prop;
if (columnInfo.TableName == tableName && columns.TryGetValue(columnInfo.OriginName, out prop))
{
var value = column.ToObject(prop.PropertyType);
prop.SetValue(builderInst, value, null);
}
}
return build(builderInst);
});
}
/// <summary>
/// Deletes all rows in a given table.
/// </summary>
/// <param name="This">The database connection.</param>
/// <typeparam name="T">The mapped type.</typeparam>
public static void DeleteAllRows <T>(this IDatabaseConnection This)
{
var tableMapping = TableMapping.Get <T>();
This.Execute(SQLBuilder.DeleteAll(tableMapping.TableName));
}
/// <summary>
/// Drops the table if it exists. Otherwise this is a no-op.
/// </summary>
/// <param name="This">The database connection.</param>
/// <typeparam name="T">The mapped type.</typeparam>
/// <seealso href="https://www.sqlite.org/lang_droptable.html"/>
public static void DropTableIfExists <T>(this IDatabaseConnection This)
{
var tableMapping = TableMapping.Get <T>();
This.Execute(SQLBuilder.DropTableIfExists(tableMapping.TableName));
}
internal static string PrimaryKeyColumn(this TableMapping This) =>
primaryKeyColumn.GetValue(This, mapping =>
// Intentionally throw if the column doesn't have a primary key
mapping.Columns.Where(x =>
x.Value.Metadata.IsPrimaryKeyPart).Select(x => x.Key).First());
