udeServer/internal/logic/pagination.go

package logic

import "math"

const (
	defaultPage     = 1
	defaultPageSize = 10
	maxPageSize     = 100
)

// normalizePage applies defaults and bounds to the requested page/pageSize,
// and keeps the computed offset within int64 even for absurd page numbers.
func normalizePage(page, pageSize int64) (int64, int64) {
	if page < 1 {
		page = defaultPage
	}
	if pageSize < 1 {
		pageSize = defaultPageSize
	}
	if pageSize > maxPageSize {
		pageSize = maxPageSize
	}

	const safeOffset = math.MaxInt64 / 2
	if page-1 > safeOffset/pageSize {
		page = safeOffset/pageSize + 1
	}

	return page, pageSize
}