package file

import (
	"fmt"
	"git.0x7f.app/WOJ/woj-server/pkg/utils"
	"os"
)

type LimitedWriter struct {
	File  *os.File
	Limit int64
	n     int64
}

func (lw *LimitedWriter) Write(p []byte) (int, error) {
	remaining := lw.Limit - lw.n
	if remaining <= 0 {
		return 0, fmt.Errorf("write limit exceeded")
	}

	var err, err2 error
	var n int

	writeLen := int64(len(p))
	if writeLen > remaining {
		err = fmt.Errorf("write limit exceeded")
		writeLen = remaining
	}

	n, err2 = lw.File.Write(p[:writeLen])
	lw.n += int64(n)

	return n, utils.If(err2 != nil, err2, err)
}