1 files changed, 53 insertions, 0 deletions
diff --git a/src/view/sort.ts b/src/view/sort.ts
new file mode 100644
index 0000000..3fed7fd
--- /dev/null
+++ b/src/view/sort.ts
@@ -0,0 +1,53 @@
+import * as Food from 'food'
+import * as Search from 'lib/search'
+
+export interface Sort {
+  field: Field,
+  order: Order,
+}
+
+export enum Field {
+  Name,
+  GlycemicIndex,
+  Carbohydrates,
+  GlycemicLoad,
+}
+
+export enum Order {
+  Down,
+  Up,
+}
+
+export const init: Sort = {
+  field: Field.Name,
+  order: Order.Down,
+}
+
+export function aliments(a1: Food.Aliment, a2: Food.Aliment, sort: Sort) {
+  return getField(a1, sort.field) > getField(a2, sort.field)
+    ? (sort.order === Order.Down ? 1 : -1)
+    : (sort.order === Order.Down ? -1 : 1)
+}
+
+function getField(a: Food.Aliment, sort: Field) {
+  if (sort === Field.Name) {
+    return Search.format(a.name)
+  } else if (sort === Field.GlycemicIndex) {
+    return a.glycemicIndex
+  } else if (sort === Field.Carbohydrates) {
+    return a.carbohydrates
+  } else {
+    return Food.glycemicLoad(a)
+  }
+}
+
+export function toggle(sort: Sort, field: Field): Sort {
+  return {
+    field,
+    order: sort.field === field ? reverseOrder(sort.order) : Order.Down
+  }
+}
+
+function reverseOrder(order: Order): Order {
+  return order === Order.Down ? Order.Up : Order.Down
+}