package api

import "strconv"

const (
	defaultPageLimit = 50
	maxPageLimit     = 500
)

func parseLimitOffset(limitStr, offsetStr string) (limit, offset int) {
	limit, _ = strconv.Atoi(limitStr)
	offset, _ = strconv.Atoi(offsetStr)
	if limit <= 0 {
		limit = defaultPageLimit
	}
	if limit > maxPageLimit {
		limit = maxPageLimit
	}
	if offset < 0 {
		offset = 0
	}
	return limit, offset
}

func paginateSlice[T any](items []T, limit, offset int) ([]T, int) {
	total := len(items)
	if offset >= total {
		return nil, total
	}
	end := offset + limit
	if end > total {
		end = total
	}
	return items[offset:end], total
}