feat: day of the week literals

src/lib/on.spec.ts

@@ -8,4 +8,8 @@ describe('on', () => {
   it('should provide on 3rd day of the month', () => {
     expect(onDayOfTheMonth(3).toString()).toBe('0 0 3 * *');
   });
+
+  it('should provide day of the week using literals', () => {
+    expect(onDayOfTheWeek('Sunday').toString()).toBe('0 0 * * 0');
+  });
 });

src/lib/on.ts

@@ -1,5 +1,14 @@
 import { DayOfTheMonthExpression, DayOfTheWeekExpression } from './expression';
 
+/**
+ * In specific day of the month
+ *
+ * ```
+ * onDayOfTheMonth(3); // * * 3 * *
+ * onDayOfTheMonth([3,5]); // * * 3,5 * *
+ * ```
+ *
+ */
 export const onDayOfTheMonth = (
   dayOfTheMonth: DayOfTheMonth | DayOfTheMonth[]
 ) => {
@@ -12,12 +21,51 @@ export const onDayOfTheMonth = (
   });
 };
 
-export const onDayOfTheWeek = (dayOfTheWeek: DayOfTheWeek | DayOfTheWeek[]) => {
+const map = {
+  Monday: 1,
+  Tuesday: 2,
+  Wednesday: 3,
+  Thursday: 4,
+  Friday: 5,
+  Saturday: 6,
+  Sunday: 0,
+};
+
+/**
+ * In specific day of the week
+ *
+ * ```
+ * onDayOfTheWeek(3); // 0 0 * * 3
+ * onDayOfTheWeek([3,5]); // 0 0 * * 3,5
+ *
+ * onDayOfTheWeek('Monday'); // 0 0 * * 1
+ * onDayOfTheWeek(['Sunday', 'Thursday']); // 0 0 * * 0,4
+ * ```
+ */
+export const onDayOfTheWeek = (
+  dayOfTheWeek:
+    | DayOfTheWeek
+    | DayOfTheWeek[]
+    | DayOfTheWeekLiteral
+    | DayOfTheWeekLiteral[]
+) => {
+  const arrayInput = Array.isArray(dayOfTheWeek)
+    ? dayOfTheWeek
+    : [dayOfTheWeek];
+
+  if (typeof arrayInput[0] === 'string') {
+    return new DayOfTheWeekExpression({
+      minute: '0',
+      hour: '0',
+      dayOfTheWeek: (arrayInput as DayOfTheWeekLiteral[])
+        .map((day) => map[day])
+        .join(','),
+    });
+  }
+
   return new DayOfTheWeekExpression({
     minute: '0',
     hour: '0',
-    dayOfTheWeek: `${
-      Array.isArray(dayOfTheWeek) ? dayOfTheWeek.join(',') : dayOfTheWeek
-    }`,
+    dayOfTheWeek: arrayInput.join(','),
   });
 };

src/lib/types.ts

@@ -140,4 +140,13 @@ type DayOfTheMonth =
   | 31;
 
 // eslint-disable-next-line @typescript-eslint/no-unused-vars
-type DayOfTheWeek = 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7;
+type DayOfTheWeek = 0 | 1 | 2 | 3 | 4 | 5 | 6;
+// eslint-disable-next-line @typescript-eslint/no-unused-vars
+type DayOfTheWeekLiteral =
+  | 'Monday'
+  | 'Tuesday'
+  | 'Wednesday'
+  | 'Thursday'
+  | 'Friday'
+  | 'Saturday'
+  | 'Sunday';