// GoToSocial
// Copyright (C) GoToSocial Authors admin@gotosocial.org
// SPDX-License-Identifier: AGPL-3.0-or-later
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

package util

type Number interface {
	~int | ~int8 | ~int16 | ~int32 | ~int64 |
		~uint | ~uint8 | ~uint16 | ~uint32 | ~uint64 |
		~uintptr | ~float32 | ~float64
}

// Decr performs a safe decrement of
// n, clamping minimum value at zero.
func Decr[N Number](n N) N {
	if n <= 0 {
		return 0
	}
	return n - 1
}

// Div performs a safe division of
// n1 and n2, checking for zero n2. In the
// case of zero n2, zero is returned.
func Div[N Number](n1, n2 N) N {
	if n2 == 0 {
		return 0
	}
	return n1 / n2
}