// Copyright The Helm Authors.
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at

// http://www.apache.org/licenses/LICENSE-2.0

// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package helmpath

import (
	"os"
	"path/filepath"

	"github.com/open-hand/helm/pkg/helmpath/xdg"
)

// lazypath is an lazy-loaded path buffer for the XDG base directory specification.
type lazypath string

func (l lazypath) path(envVar string, defaultFn func() string, elem ...string) string {
	base := os.Getenv(envVar)
	if base == "" {
		base = defaultFn()
	}
	return filepath.Join(base, string(l), filepath.Join(elem...))
}

// cachePath defines the base directory relative to which user specific non-essential data files
// should be stored.
func (l lazypath) cachePath(elem ...string) string {
	return l.path(xdg.CacheHomeEnvVar, cacheHome, filepath.Join(elem...))
}

// configPath defines the base directory relative to which user specific configuration files should
// be stored.
func (l lazypath) configPath(elem ...string) string {
	return l.path(xdg.ConfigHomeEnvVar, configHome, filepath.Join(elem...))
}

// dataPath defines the base directory relative to which user specific data files should be stored.
func (l lazypath) dataPath(elem ...string) string {
	return l.path(xdg.DataHomeEnvVar, dataHome, filepath.Join(elem...))
}
