package say

// The counted noun, in the form the number in front of it demands.
//
// Russian inflects a noun after a numeral, and the form depends on the last two
// digits: 1 градус, 2 градуса, 5 градусов, 11 градусов, 21 градус, 22 градуса.
// A line file cannot spell that out, so a count in a template splits into two
// placeholders — the number, and {word} filled from here.
//
// The rule lived once as hostWord in cmd/mavend/netscan.go and once as
// pluralDaysRU in internal/memory, which meant the weather line said "градусов"
// for every temperature and the task list said "дн." — a written abbreviation
// read aloud. One helper, every count site (Vikunja #521).

import "math"

// CountWord picks between the three forms n needs: one for 1, few for 2-4, many
// for 0, 5-20 and anything ending in those. A negative count reads its own
// magnitude, since minus does not change the noun: -2 градуса.
func CountWord(n int, one, few, many string) string {
	if n < 0 {
		n = -n
	}
	if n%100 >= 11 && n%100 <= 14 {
		return many
	}
	switch n % 10 {
	case 1:
		return one
	case 2, 3, 4:
		return few
	default:
		return many
	}
}

// Degrees — the noun for a temperature. Takes the reading as it arrives from a
// weather provider and counts by the whole degrees she is about to say, so the
// noun agrees with the number in the same sentence rather than with the reading
// behind it.
func Degrees(temp float64) string {
	return CountWord(int(math.Round(temp)), "градус", "градуса", "градусов")
}

// Devices — the noun for a count of hosts on the LAN or of smart-home devices.
func Devices(n int) string {
	return CountWord(n, "устройство", "устройства", "устройств")
}

// Days — the noun for a stretch of days. This is what replaces «дн.» in the
// overdue and due-soon reasons: an abbreviation is written shorthand, and every
// one of these lines is spoken.
func Days(n int) string {
	return CountWord(n, "день", "дня", "дней")
}