package fees

const JuniorFeeDefault = 500 // CZK fallback for 2+ practices when month not in JuniorFeeMonthlyRate

// JuniorFeeMonthlyRate mirrors JUNIOR_MONTHLY_RATE in scripts/attendance.py.
// Months absent from this map fall back to JuniorFeeDefault.
var JuniorFeeMonthlyRate = map[string]int{
	"2025-09": 250,
	"2026-03": 250,
}

// Expected is the result of a junior fee calculation.
// When Unknown is true the fee requires manual review (Python returns "?");
// in that case Value is meaningless — always check Unknown first.
type Expected struct {
	Value   int
	Unknown bool
}

// CalculateJuniorFee returns the junior fee for attendanceCount practices in
// the given monthKey (format "YYYY-MM").
//
//	0 practices → Expected{Value: 0}
//	1 practice  → Expected{Unknown: true}  (manual review; Python sentinel "?")
//	2+          → Expected{Value: JuniorFeeMonthlyRate[monthKey] or JuniorFeeDefault}
func CalculateJuniorFee(attendanceCount int, monthKey string) Expected {
	if attendanceCount == 0 {
		return Expected{Value: 0}
	}
	if attendanceCount == 1 {
		return Expected{Unknown: true}
	}
	if rate, ok := JuniorFeeMonthlyRate[monthKey]; ok {
		return Expected{Value: rate}
	}
	return Expected{Value: JuniorFeeDefault}
}