From c17dcb8930a82f961b490e877bc339faeb81c33b Mon Sep 17 00:00:00 2001
From: Alexis Hernandez <alexis22229@gmail.com>
Date: Sun, 15 Apr 2018 00:27:08 -0500
Subject: [PATCH] server: Add FieldOrderingSQLInterpreter

---
 .../interpreters/ColumnNameResolver.scala      | 11 +++++++++++
 .../FieldOrderingSQLInterpreter.scala          | 18 ++++++++++++++++++
 2 files changed, 29 insertions(+)
 create mode 100644 server/app/com/xsn/explorer/data/anorm/interpreters/ColumnNameResolver.scala
 create mode 100644 server/app/com/xsn/explorer/data/anorm/interpreters/FieldOrderingSQLInterpreter.scala

diff --git a/server/app/com/xsn/explorer/data/anorm/interpreters/ColumnNameResolver.scala b/server/app/com/xsn/explorer/data/anorm/interpreters/ColumnNameResolver.scala
new file mode 100644
index 0000000..7723d09
--- /dev/null
+++ b/server/app/com/xsn/explorer/data/anorm/interpreters/ColumnNameResolver.scala
@@ -0,0 +1,11 @@
+package com.xsn.explorer.data.anorm.interpreters
+
+import scala.annotation.implicitNotFound
+
+@implicitNotFound(
+  "No column name resolver found for type ${A}. Try to implement an implicit ColumnNameResolver for this type."
+)
+trait ColumnNameResolver[A] {
+
+  def getColumnName(field: A): String
+}
diff --git a/server/app/com/xsn/explorer/data/anorm/interpreters/FieldOrderingSQLInterpreter.scala b/server/app/com/xsn/explorer/data/anorm/interpreters/FieldOrderingSQLInterpreter.scala
new file mode 100644
index 0000000..a5df63a
--- /dev/null
+++ b/server/app/com/xsn/explorer/data/anorm/interpreters/FieldOrderingSQLInterpreter.scala
@@ -0,0 +1,18 @@
+package com.xsn.explorer.data.anorm.interpreters
+
+import com.xsn.explorer.models.base.{FieldOrdering, OrderingCondition}
+
+class FieldOrderingSQLInterpreter {
+
+  def toOrderByClause[A](fieldOrdering: FieldOrdering[A])(implicit columnNameResolver: ColumnNameResolver[A]) = {
+    val field = columnNameResolver.getColumnName(fieldOrdering.field)
+    val condition = getCondition(fieldOrdering.orderingCondition)
+
+    s"ORDER BY $field $condition"
+  }
+
+  private def getCondition(ordering: OrderingCondition) = ordering match {
+    case OrderingCondition.AscendingOrder => "ASC"
+    case OrderingCondition.DescendingOrder => "DESC"
+  }
+}