// FIXME: Do more extensive tests (ex: create multiple, delete, recreate;
//       create multiple, check the amount of images and paths, etc..)
func TestGraphCreate(t *testing.T) {
	graph, _ := tempGraph(t)
	defer nukeGraph(graph)
	archive, err := fakeTar()
	if err != nil {
		t.Fatal(err)
	}
	img, err := graph.Create(archive, "", "", "Testing", "", nil, nil)
	if err != nil {
		t.Fatal(err)
	}
	if err := utils.ValidateID(img.ID); err != nil {
		t.Fatal(err)
	}
	if img.Comment != "Testing" {
		t.Fatalf("Wrong comment: should be '%s', not '%s'", "Testing", img.Comment)
	}
	if img.DockerVersion != dockerversion.VERSION {
		t.Fatalf("Wrong docker_version: should be '%s', not '%s'", dockerversion.VERSION, img.DockerVersion)
	}
	images, err := graph.Map()
	if err != nil {
		t.Fatal(err)
	} else if l := len(images); l != 1 {
		t.Fatalf("Wrong number of images. Should be %d, not %d", 1, l)
	}
	if images[img.ID] == nil {
		t.Fatalf("Could not find image with id %s", img.ID)
	}
}

func validateRemoteName(remoteName string) error {
	var (
		namespace string
		name      string
	)
	nameParts := strings.SplitN(remoteName, "/", 2)
	if len(nameParts) < 2 {
		namespace = "library"
		name = nameParts[0]

		// the repository name must not be a valid image ID
		if err := utils.ValidateID(name); err == nil {
			return fmt.Errorf("Invalid repository name (%s), cannot specify 64-byte hexadecimal strings", name)
		}
	} else {
		namespace = nameParts[0]
		name = nameParts[1]
	}
	if !validNamespaceChars.MatchString(namespace) {
		return fmt.Errorf("Invalid namespace name (%s). Only [a-z0-9-_] are allowed.", namespace)
	}
	if len(namespace) < 4 || len(namespace) > 30 {
		return fmt.Errorf("Invalid namespace name (%s). Cannot be fewer than 4 or more than 30 characters.", namespace)
	}
	if strings.HasPrefix(namespace, "-") || strings.HasSuffix(namespace, "-") {
		return fmt.Errorf("Invalid namespace name (%s). Cannot begin or end with a hyphen.", namespace)
	}
	if strings.Contains(namespace, "--") {
		return fmt.Errorf("Invalid namespace name (%s). Cannot contain consecutive hyphens.", namespace)
	}
	if !validRepo.MatchString(name) {
		return fmt.Errorf("Invalid repository name (%s), only [a-z0-9-_.] are allowed", name)
	}
	return nil
}

func LoadImage(root string) (*Image, error) {
	// Load the json data
	jsonData, err := ioutil.ReadFile(jsonPath(root))
	if err != nil {
		return nil, err
	}
	img := &Image{}

	if err := json.Unmarshal(jsonData, img); err != nil {
		return nil, err
	}
	if err := utils.ValidateID(img.ID); err != nil {
		return nil, err
	}

	if buf, err := ioutil.ReadFile(path.Join(root, "layersize")); err != nil {
		if !os.IsNotExist(err) {
			return nil, err
		}
		// If the layersize file does not exist then set the size to a negative number
		// because a layer size of 0 (zero) is valid
		img.Size = -1
	} else {
		size, err := strconv.Atoi(string(buf))
		if err != nil {
			return nil, err
		}
		img.Size = int64(size)
	}

	return img, nil
}

func validateRepositoryName(repositoryName string) error {
	var (
		namespace string
		name      string
	)
	nameParts := strings.SplitN(repositoryName, "/", 2)
	if len(nameParts) < 2 {
		namespace = "library"
		name = nameParts[0]

		// the repository name must not be a valid image ID
		if err := utils.ValidateID(name); err == nil {
			return fmt.Errorf("Invalid repository name (%s), cannot specify 64-byte hexadecimal strings", name)
		}
	} else {
		namespace = nameParts[0]
		name = nameParts[1]
	}
	if !validNamespace.MatchString(namespace) {
		return fmt.Errorf("Invalid namespace name (%s), only [a-z0-9_] are allowed, size between 4 and 30", namespace)
	}
	if !validRepo.MatchString(name) {
		return fmt.Errorf("Invalid repository name (%s), only [a-z0-9-_.] are allowed", name)
	}
	return nil
}

// Register imports a pre-existing image into the graph.
func (graph *Graph) Register(img *image.Image, jsonData []byte, layerData archive.ArchiveReader) (err error) {
	defer func() {
		// If any error occurs, remove the new dir from the driver.
		// Don't check for errors since the dir might not have been created.
		// FIXME: this leaves a possible race condition.
		if err != nil {
			graph.driver.Remove(img.ID)
		}
	}()
	if err := utils.ValidateID(img.ID); err != nil {
		return err
	}
	// (This is a convenience to save time. Race conditions are taken care of by os.Rename)
	if graph.Exists(img.ID) {
		return fmt.Errorf("Image %s already exists", img.ID)
	}

	// Ensure that the image root does not exist on the filesystem
	// when it is not registered in the graph.
	// This is common when you switch from one graph driver to another
	if err := os.RemoveAll(graph.ImageRoot(img.ID)); err != nil && !os.IsNotExist(err) {
		return err
	}

	// If the driver has this ID but the graph doesn't, remove it from the driver to start fresh.
	// (the graph is the source of truth).
	// Ignore errors, since we don't know if the driver correctly returns ErrNotExist.
	// (FIXME: make that mandatory for drivers).
	graph.driver.Remove(img.ID)

	tmp, err := graph.Mktemp("")
	defer os.RemoveAll(tmp)
	if err != nil {
		return fmt.Errorf("Mktemp failed: %s", err)
	}

	// Create root filesystem in the driver
	if err := graph.driver.Create(img.ID, img.Parent); err != nil {
		return fmt.Errorf("Driver %s failed to create image rootfs %s: %s", graph.driver, img.ID, err)
	}
	// Mount the root filesystem so we can apply the diff/layer
	rootfs, err := graph.driver.Get(img.ID, "")
	if err != nil {
		return fmt.Errorf("Driver %s failed to get image rootfs %s: %s", graph.driver, img.ID, err)
	}
	defer graph.driver.Put(img.ID)
	img.SetGraph(graph)
	if err := image.StoreImage(img, jsonData, layerData, tmp, rootfs); err != nil {
		return err
	}
	// Commit
	if err := os.Rename(tmp, graph.ImageRoot(img.ID)); err != nil {
		return err
	}
	graph.idIndex.Add(img.ID)
	return nil
}

func (s *TagStore) recursiveLoad(eng *engine.Engine, address, tmpImageDir string) error {
	if err := eng.Job("image_get", address).Run(); err != nil {
		logrus.Debugf("Loading %s", address)

		imageJson, err := ioutil.ReadFile(path.Join(tmpImageDir, "repo", address, "json"))
		if err != nil {
			logrus.Debugf("Error reading json", err)
			return err
		}

		layer, err := os.Open(path.Join(tmpImageDir, "repo", address, "layer.tar"))
		if err != nil {
			logrus.Debugf("Error reading embedded tar", err)
			return err
		}
		img, err := image.NewImgJSON(imageJson)
		if err != nil {
			logrus.Debugf("Error unmarshalling json", err)
			return err
		}
		if err := utils.ValidateID(img.ID); err != nil {
			logrus.Debugf("Error validating ID: %s", err)
			return err
		}

		// ensure no two downloads of the same layer happen at the same time
		if c, err := s.poolAdd("pull", "layer:"+img.ID); err != nil {
			if c != nil {
				logrus.Debugf("Image (id: %s) load is already running, waiting: %v", img.ID, err)
				<-c
				return nil
			}

			return err
		}

		defer s.poolRemove("pull", "layer:"+img.ID)

		if img.Parent != "" {
			if !s.graph.Exists(img.Parent) {
				if err := s.recursiveLoad(eng, img.Parent, tmpImageDir); err != nil {
					return err
				}
			}
		}
		if err := s.graph.Register(img, layer); err != nil {
			return err
		}
	}
	logrus.Debugf("Completed processing %s", address)

	return nil
}

func (s *TagStore) recursiveLoad(eng *engine.Engine, address, tmpImageDir string) error {
	if err := eng.Job("image_get", address).Run(); err != nil {
		log.Debugf("Loading %s", address)

		imageJson, err := ioutil.ReadFile(path.Join(tmpImageDir, "repo", address, "json"))
		if err != nil {
			log.Debugf("Error reading json", err)
			return err
		}

		layer, err := os.Open(path.Join(tmpImageDir, "repo", address, "layer.tar"))
		if err != nil {
			log.Debugf("Error reading embedded tar", err)
			return err
		}
		img, err := image.NewImgJSON(imageJson)
		if err != nil {
			log.Debugf("Error unmarshalling json", err)
			return err
		}
		if err := utils.ValidateID(img.ID); err != nil {
			log.Debugf("Error validating ID: %s", err)
			return err
		}
		if img.Parent != "" {
			if !s.graph.Exists(img.Parent) {
				if err := s.recursiveLoad(eng, img.Parent, tmpImageDir); err != nil {
					return err
				}
			}
		}
		if err := s.graph.Register(img, layer); err != nil {
			return err
		}
	}
	log.Debugf("Completed processing %s", address)

	return nil
}

func LoadImage(root string) (*Image, error) {
	// Open the JSON file to decode by streaming
	jsonSource, err := os.Open(jsonPath(root))
	if err != nil {
		return nil, err
	}
	defer jsonSource.Close()

	img := &Image{}
	dec := json.NewDecoder(jsonSource)

	// Decode the JSON data
	if err := dec.Decode(img); err != nil {
		return nil, err
	}
	if err := utils.ValidateID(img.ID); err != nil {
		return nil, err
	}

	if buf, err := ioutil.ReadFile(path.Join(root, "layersize")); err != nil {
		if !os.IsNotExist(err) {
			return nil, err
		}
		// If the layersize file does not exist then set the size to a negative number
		// because a layer size of 0 (zero) is valid
		img.Size = -1
	} else {
		// Using Atoi here instead would temporarily convert the size to a machine
		// dependent integer type, which causes images larger than 2^31 bytes to
		// display negative sizes on 32-bit machines:
		size, err := strconv.ParseInt(string(buf), 10, 64)
		if err != nil {
			return nil, err
		}
		img.Size = int64(size)
	}

	return img, nil
}