package git

import (
	"bytes"
	"io"
)

func truncateCommandOutput(out io.Reader, maxBytes int64) (string, bool, error) {
	var buf []byte
	var err error

	if maxBytes < 0 {
		buf, err = io.ReadAll(out)
	} else {
		buf, err = io.ReadAll(io.LimitReader(out, maxBytes))
	}
	if err != nil {
		return "", false, err
	}
	truncated := len(buf) >= int(maxBytes)
	// Remove the last line if it's truncated
	if truncated {
		// Find the index of the last newline character
		lastNewline := bytes.LastIndexByte(buf, '\n')

		if lastNewline > 0 {
			// Trim the data buffer up to the last newline character
			buf = buf[:lastNewline]
		}
	}

	return string(buf), truncated, nil
}