package common

import (
	"unicode/utf8"

	"github.com/labring/aiproxy/core/common/conv"
)

func TruncateByRune[T ~string](s T, length int) T {
	total := 0
	for _, r := range s {
		runeLen := utf8.RuneLen(r)
		if runeLen == -1 || total+runeLen > length {
			return s[:total]
		}

		total += runeLen
	}

	return s[:total]
}

func TruncateBytesByRune(b []byte, length int) []byte {
	total := 0
	for _, r := range conv.BytesToString(b) {
		runeLen := utf8.RuneLen(r)
		if runeLen == -1 || total+runeLen > length {
			return b[:total]
		}

		total += runeLen
	}

	return b[:total]
}