package fsutil

import (
	"os"
)

// Return true if os.Stat doesn't return an error.
func PathExists(path string) bool {
	_, err := os.Stat(path)
	return err == nil
}

// Returns true if os.Stat doesn't return an error and the path is a regular file.
func FileExists(path string) bool {
	fi, err := os.Stat(path)
	if err != nil {
		return false
	}
	return fi.Mode().IsRegular()
}

// Returns true if os.Stat doesn't return an error and the path is a directory.
func DirExists(path string) bool {
	fi, err := os.Stat(path)
	if err != nil {
		return false
	}
	return fi.Mode().IsDir()
}

// Write a file atomically on a POSIX file system.
func WriteFileAtomic(data []byte, tmpPath, finalPath string) error {
	f, err := os.Create(tmpPath)
	if err != nil {
		return err
	}

	if _, err := f.Write(data); err != nil {
		f.Close()
		return err
	}

	if err := f.Sync(); err != nil {
		f.Close()
		return err
	}

	if err := f.Close(); err != nil {
		return err
	}

	return os.Rename(tmpPath, finalPath)
}