chore: initialize public repository

app/services/workdays.py

@@ -0,0 +1,37 @@
+from datetime import date
+
+
+DEFAULT_WORKING_DAYS = (0, 1, 2, 3, 4)
+
+
+def normalize_working_days(days: list[int] | set[int] | tuple[int, ...]) -> list[int]:
+    normalized = sorted({int(day) for day in days if 0 <= int(day) <= 6})
+    if not normalized:
+        return list(DEFAULT_WORKING_DAYS)
+    return normalized
+
+
+def serialize_working_days(days: list[int] | set[int] | tuple[int, ...]) -> str:
+    return ",".join(str(day) for day in normalize_working_days(days))
+
+
+def parse_working_days_csv(value: str | None) -> set[int]:
+    if not value:
+        return set(DEFAULT_WORKING_DAYS)
+
+    parsed: list[int] = []
+    for part in value.split(","):
+        item = part.strip()
+        if not item:
+            continue
+        try:
+            parsed.append(int(item))
+        except ValueError:
+            continue
+
+    normalized = normalize_working_days(parsed)
+    return set(normalized)
+
+
+def is_workday(day: date, relevant_weekdays: set[int]) -> bool:
+    return day.weekday() in relevant_weekdays