package localfs

import (
	"errors"
	"io"
	"io/ioutil"
	"net/http"
	"os"
	"path"

	"github.com/andreimarcu/linx-server/backends"
)

type LocalfsBackend struct {
	basePath string
}

func (b LocalfsBackend) Delete(key string) error {
	return os.Remove(path.Join(b.basePath, key))
}

func (b LocalfsBackend) Exists(key string) (bool, error) {
	_, err := os.Stat(path.Join(b.basePath, key))
	return err == nil, err
}

func (b LocalfsBackend) Get(key string) ([]byte, error) {
	return ioutil.ReadFile(path.Join(b.basePath, key))
}

func (b LocalfsBackend) Put(key string, r io.Reader) (int64, error) {
	dst, err := os.Create(path.Join(b.basePath, key))
	if err != nil {
		return 0, err
	}
	defer dst.Close()

	bytes, err := io.Copy(dst, r)
	if bytes == 0 {
		b.Delete(key)
		return bytes, errors.New("Empty file")
	} else if err != nil {
		b.Delete(key)
		return bytes, err
	}

	return bytes, err
}

func (b LocalfsBackend) Open(key string) (backends.ReadSeekCloser, error) {
	return os.Open(path.Join(b.basePath, key))
}

func (b LocalfsBackend) ServeFile(key string, w http.ResponseWriter, r *http.Request) {
	filePath := path.Join(b.basePath, key)
	http.ServeFile(w, r, filePath)
}

func (b LocalfsBackend) Size(key string) (int64, error) {
	fileInfo, err := os.Stat(path.Join(b.basePath, key))
	if err != nil {
		return 0, err
	}

	return fileInfo.Size(), nil
}

func (b LocalfsBackend) List() ([]string, error) {
	var output []string

	files, err := ioutil.ReadDir(b.basePath)
	if err != nil {
		return nil, err
	}

	for _, file := range files {
		output = append(output, file.Name())
	}

	return output, nil
}

func NewLocalfsBackend(basePath string) LocalfsBackend {
	return LocalfsBackend{basePath: basePath}
}