meal plan dialog

vue3/src/utils/date_utils.ts

@@ -2,13 +2,38 @@ import {DateTime} from "luxon";
 
 /**
  * shifts a range of dates/any array of dates by the number of days given in the day modifier (can be positive or negative)
- * @param dateRange
- * @param dayModifier
+ * @param dateRange array of dates
+ * @param dayModifier number of days to modify array of dates with
+ * @return dateRange array of dates modified
  */
-export function shiftDateRange(dateRange: Date[], dayModifier: number){
+export function shiftDateRange(dateRange: Date[], dayModifier: number) {
     let newDateRange: Date[] = []
     dateRange.forEach(date => {
         newDateRange.push(DateTime.fromJSDate(date).plus({'days': dayModifier}).toJSDate())
     })
     return newDateRange
+}
+
+/**
+ * adjust the length of a date range by either adding or removing the given number of days
+ * when adding days to an empty date Range it starts with the current date
+ * @param dateRange array of dates
+ * @param dayModifier number of days to modify array of dates with
+ * @return dateRange sorted array of dates modified
+ */
+export function adjustDateRangeLength(dateRange: Date[], dayModifier: number) {
+    dateRange = dateRange.sort((a: Date, b: Date) => a.getTime() - b.getTime());
+    if (dayModifier < 0) {
+        dateRange.splice(dateRange.length - Math.abs(dayModifier), Math.abs(dayModifier))
+    } else {
+        if (dateRange.length == 0) {
+            dateRange.push(new Date())
+        } else {
+            let lastDate = DateTime.fromJSDate(dateRange[dateRange.length - 1])
+            for (let i = 0; i < dayModifier; i++) {
+                dateRange.push(lastDate.plus({'days': (i + 1)}).toJSDate())
+            }
+        }
+    }
+    return dateRange
 }