package image

 
 import (

 	"encoding/json"

 	"errors"
 	"io"

 	"time"
 

 	"github.com/docker/distribution/digest"

 	"github.com/docker/engine-api/types/container"

 )
 

 // ID is the content-addressable ID of an image.
 type ID digest.Digest

 func (id ID) String() string {
 	return digest.Digest(id).String()

 }
 

 // V1Image stores the V1 image configuration.
 type V1Image struct {

 	// ID a unique 64 character identifier of the image

 	ID string `json:"id,omitempty"`

 	// Parent id of the image
 	Parent string `json:"parent,omitempty"`
 	// Comment user added comment
 	Comment string `json:"comment,omitempty"`
 	// Created timestamp when image was created
 	Created time.Time `json:"created"`
 	// Container is the id of the container used to commit
 	Container string `json:"container,omitempty"`

 	// ContainerConfig is the configuration of the container that is committed into the image

 	ContainerConfig container.Config `json:"container_config,omitempty"`

 	// DockerVersion specifies version on which image is built
 	DockerVersion string `json:"docker_version,omitempty"`
 	// Author of the image
 	Author string `json:"author,omitempty"`
 	// Config is the configuration of the container received from the client

 	Config *container.Config `json:"config,omitempty"`

 	// Architecture is the hardware that the image is build and runs on
 	Architecture string `json:"architecture,omitempty"`
 	// OS is the operating system used to build and run the image
 	OS string `json:"os,omitempty"`
 	// Size is the total size of the image including all layers it is composed of

 	Size int64 `json:",omitempty"`

 }
 

 // Image stores the image configuration
 type Image struct {
 	V1Image

 	Parent     ID        `json:"parent,omitempty"`
 	RootFS     *RootFS   `json:"rootfs,omitempty"`
 	History    []History `json:"history,omitempty"`
 	OSVersion  string    `json:"os.version,omitempty"`
 	OSFeatures []string  `json:"os.features,omitempty"`

 	// rawJSON caches the immutable JSON associated with this image.
 	rawJSON []byte
 
 	// computedID is the ID computed from the hash of the image config.
 	// Not to be confused with the legacy V1 ID in V1Image.
 	computedID ID

 }
 

 // RawJSON returns the immutable JSON associated with the image.
 func (img *Image) RawJSON() []byte {
 	return img.rawJSON
 }
 
 // ID returns the image's content-addressable ID.
 func (img *Image) ID() ID {
 	return img.computedID

 }

 // ImageID stringizes ID.
 func (img *Image) ImageID() string {
 	return string(img.ID())
 }
 
 // RunConfig returns the image's container config.
 func (img *Image) RunConfig() *container.Config {
 	return img.Config
 }
 

 // MarshalJSON serializes the image to JSON. It sorts the top-level keys so
 // that JSON that's been manipulated by a push/pull cycle with a legacy
 // registry won't end up with a different key order.
 func (img *Image) MarshalJSON() ([]byte, error) {
 	type MarshalImage Image

 	pass1, err := json.Marshal(MarshalImage(*img))

 	if err != nil {
 		return nil, err
 	}
 
 	var c map[string]*json.RawMessage

 	if err := json.Unmarshal(pass1, &c); err != nil {

 		return nil, err
 	}
 	return json.Marshal(c)
 }
 

 // History stores build commands that were used to create an image
 type History struct {
 	// Created timestamp for build point
 	Created time.Time `json:"created"`
 	// Author of the build point
 	Author string `json:"author,omitempty"`
 	// CreatedBy keeps the Dockerfile command used while building image.
 	CreatedBy string `json:"created_by,omitempty"`

 	// Comment is custom message set by the user when creating the image.

 	Comment string `json:"comment,omitempty"`
 	// EmptyLayer is set to true if this history item did not generate a
 	// layer. Otherwise, the history item is associated with the next
 	// layer in the RootFS section.
 	EmptyLayer bool `json:"empty_layer,omitempty"`

 }
 

 // Exporter provides interface for exporting and importing images
 type Exporter interface {

 	Load(io.ReadCloser, io.Writer, bool) error

 	// TODO: Load(net.Context, io.ReadCloser, <- chan StatusMessage) error
 	Save([]string, io.Writer) error
 }
 
 // NewFromJSON creates an Image configuration from json.
 func NewFromJSON(src []byte) (*Image, error) {
 	img := &Image{}
 
 	if err := json.Unmarshal(src, img); err != nil {
 		return nil, err

 	}

 	if img.RootFS == nil {
 		return nil, errors.New("Invalid image JSON, no RootFS key.")
 	}
 
 	img.rawJSON = src
 
 	return img, nil

 }