// fs implements galaxy/storage.Storage with filesystem
package fs

import (
	"fmt"
	"galaxy/util"
)

type fsStorage struct {
	path string
}

// NewFS returns on-filesystem implementation of the "galaxy/storage.Storage" with root located at rootPath.
// rootPath must me a directory and has write access to the current user. If initial checks failed, return nil and non-nil error.
func NewStorage(path string) (*fsStorage, error) {
	if ok, err := util.PathExists(path, true); err != nil {
		return nil, fmt.Errorf("new storage: check path %q exists: %w", path, err)
	} else if !ok {
		return nil, fmt.Errorf("new storage: path %q does not exists", path)
	}
	if ok, err := util.Writable(path); err != nil {
		return nil, fmt.Errorf("new storage: check path %q writable: %w", path, err)
	} else if !ok {
		return nil, fmt.Errorf("new storage: path %q is not writable", path)
	}
	s := &fsStorage{
		path: path,
	}
	return s, nil
}