from peewee import IntegrityError

from data import model, database
from data.model import DataModelException
from endpoints.v2.models_interface import (
  Blob,
  BlobUpload,
  DockerRegistryV2DataInterface,
  ManifestJSON,
  Repository,
  RepositoryReference,
  Tag,)
from image.docker.v1 import DockerV1Metadata

_MEDIA_TYPE = "application/vnd.docker.distribution.manifest.v1+prettyjws"


class PreOCIModel(DockerRegistryV2DataInterface):
  """
  PreOCIModel implements the data model for the v2 Docker Registry protocol using a database schema
  before it was changed to support the OCI specification.
  """

  def create_repository(self, namespace_name, repo_name, creating_user=None):
    return model.repository.create_repository(namespace_name, repo_name, creating_user)

  def get_repository(self, namespace_name, repo_name):
    repo = model.repository.get_repository(namespace_name, repo_name)
    if repo is None:
      return None
    return _repository_for_repo(repo)

  def has_active_tag(self, namespace_name, repo_name, tag_name):
    try:
      model.tag.get_active_tag(namespace_name, repo_name, tag_name)
      return True
    except database.RepositoryTag.DoesNotExist:
      return False

  def has_tag(self, namespace_name, repo_name, tag_name):
    try:
      model.tag.get_possibly_expired_tag(namespace_name, repo_name, tag_name)
      return True
    except database.RepositoryTag.DoesNotExist:
      return False

  def get_manifest_by_tag(self, namespace_name, repo_name, tag_name):
    try:
      manifest = model.tag.load_tag_manifest(namespace_name, repo_name, tag_name)
      return ManifestJSON(digest=manifest.digest, json=manifest.json_data, media_type=_MEDIA_TYPE)
    except model.InvalidManifestException:
      return None

  def get_manifest_by_digest(self, namespace_name, repo_name, digest):
    try:
      manifest = model.tag.load_manifest_by_digest(namespace_name, repo_name, digest)
      return ManifestJSON(digest=digest, json=manifest.json_data, media_type=_MEDIA_TYPE)
    except model.InvalidManifestException:
      return None

  def delete_manifest_by_digest(self, namespace_name, repo_name, digest):
    def _tag_view(tag):
      return Tag(name=tag.name, repository=RepositoryReference(
        id=tag.repository_id,
        name=repo_name,
        namespace_name=namespace_name,))

    tags = model.tag.delete_manifest_by_digest(namespace_name, repo_name, digest)
    return [_tag_view(tag) for tag in tags]

  def get_docker_v1_metadata_by_tag(self, namespace_name, repo_name, tag_name):
    try:
      repo_img = model.tag.get_tag_image(namespace_name, repo_name, tag_name, include_storage=True)
      return _docker_v1_metadata(namespace_name, repo_name, repo_img)
    except DataModelException:
      return None

  def get_docker_v1_metadata_by_image_id(self, repository, docker_image_ids):
    images_query = model.image.lookup_repository_images(repository.id, docker_image_ids)
    return {
      image.docker_image_id: _docker_v1_metadata(repository.namespace_name, repository.name, image)
      for image in images_query
    }

  def get_parents_docker_v1_metadata(self, namespace_name, repo_name, docker_image_id):
    repo_image = model.image.get_repo_image(namespace_name, repo_name, docker_image_id)
    if repo_image is None:
      return []

    parents = model.image.get_parent_images(namespace_name, repo_name, repo_image)
    return [_docker_v1_metadata(namespace_name, repo_name, image) for image in parents]

  def create_manifest_and_update_tag(self, namespace_name, repo_name, tag_name, manifest_digest,
                                     manifest_bytes):
    try:
      model.tag.associate_generated_tag_manifest(namespace_name, repo_name, tag_name,
                                                 manifest_digest, manifest_bytes)
    except IntegrityError:
      # It's already there!
      pass

  def synthesize_v1_image(self, repository, storage, image_id, created, comment, command,
                          compat_json, parent_image_id):
    parent_image = None
    if parent_image_id is not None:
      parent_image = model.image.get_image(repository.id, parent_image_id)
      if parent_image is None:
        raise DataModelException('Unknown parent image: %s' % parent_image_id)

    repo_image = model.image.synthesize_v1_image(repository.id, storage.id, storage.size,
                                                 image_id, created, comment, command, compat_json,
                                                 parent_image)
    return _docker_v1_metadata(repository.namespace_name, repository.name, repo_image)

  def save_manifest(self, repository, tag_name, leaf_layer_docker_id, manifest_digest,
                    manifest_bytes):
    (_, newly_created) = model.tag.store_tag_manifest_for_repo(
      repository.id, tag_name, leaf_layer_docker_id, manifest_digest, manifest_bytes)
    return newly_created

  def repository_tags(self, namespace_name, repo_name, limit, offset):
    def _tag_view(tag):
      return Tag(name=tag.name, repository=RepositoryReference(
        id=tag.repository_id,
        name=repo_name,
        namespace_name=namespace_name,))

    tags_query = model.tag.list_repository_tags(namespace_name, repo_name)
    tags_query = tags_query.limit(limit).offset(offset)
    return [_tag_view(tag) for tag in tags_query]

  def get_visible_repositories(self, username, limit, offset, include_public=None):
    if include_public is None:
      include_public = (username is None)

    query = model.repository.get_visible_repositories(username, kind_filter='image',
                                                      include_public=include_public)
    query = query.limit(limit).offset(offset)
    return [_repository_for_repo(repo) for repo in query]

  def create_blob_upload(self, namespace_name, repo_name, upload_uuid, location_name,
                         storage_metadata):
    try:
      model.blob.initiate_upload(namespace_name, repo_name, upload_uuid, location_name,
                                 storage_metadata)
      return True
    except database.Repository.DoesNotExist:
      return False

  def blob_upload_by_uuid(self, namespace_name, repo_name, upload_uuid):
    try:
      found = model.blob.get_blob_upload(namespace_name, repo_name, upload_uuid)
    except model.InvalidBlobUpload:
      return None

    return BlobUpload(
      repo_namespace_name=namespace_name,
      repo_name=repo_name,
      uuid=upload_uuid,
      byte_count=found.byte_count,
      uncompressed_byte_count=found.uncompressed_byte_count,
      chunk_count=found.chunk_count,
      sha_state=found.sha_state,
      piece_sha_state=found.piece_sha_state,
      piece_hashes=found.piece_hashes,
      location_name=found.location.name,
      storage_metadata=found.storage_metadata,)

  def update_blob_upload(self, blob_upload):
    # Lookup the blob upload object.
    try:
      blob_upload_record = model.blob.get_blob_upload(blob_upload.repo_namespace_name,
                                                      blob_upload.repo_name, blob_upload.uuid)
    except model.InvalidBlobUpload:
      return

    blob_upload_record.uncompressed_byte_count = blob_upload.uncompressed_byte_count
    blob_upload_record.piece_hashes = blob_upload.piece_hashes
    blob_upload_record.piece_sha_state = blob_upload.piece_sha_state
    blob_upload_record.storage_metadata = blob_upload.storage_metadata
    blob_upload_record.byte_count = blob_upload.byte_count
    blob_upload_record.chunk_count = blob_upload.chunk_count
    blob_upload_record.sha_state = blob_upload.sha_state
    blob_upload_record.save()

  def delete_blob_upload(self, namespace_name, repo_name, uuid):
    try:
      found = model.blob.get_blob_upload(namespace_name, repo_name, uuid)
      found.delete_instance()
    except model.InvalidBlobUpload:
      return

  def create_blob_and_temp_tag(self, namespace_name, repo_name, blob_digest, blob_upload,
                               expiration_sec):
    location_obj = model.storage.get_image_location_for_name(blob_upload.location_name)
    blob_record = model.blob.store_blob_record_and_temp_link(
      namespace_name, repo_name, blob_digest, location_obj.id, blob_upload.byte_count,
      expiration_sec, blob_upload.uncompressed_byte_count)
    return Blob(
      id=blob_record.id,
      uuid=blob_record.uuid,
      digest=blob_digest,
      size=blob_upload.byte_count,
      locations=[blob_upload.location_name],
      cas_path=blob_record.cas_path
    )

  def lookup_blobs_by_digest(self, repository, digests):
    def _blob_view(blob_record):
      return Blob(
        id=blob_record.id,
        uuid=blob_record.uuid,
        digest=blob_record.content_checksum,
        size=blob_record.image_size,
        cas_path=blob_record.cas_path,
        locations=None,  # Note: Locations is None in this case.
      )

    query = model.storage.lookup_repo_storages_by_content_checksum(repository.id, digests)
    return {storage.content_checksum: _blob_view(storage) for storage in query}

  def get_blob_by_digest(self, namespace_name, repo_name, digest):
    try:
      blob_record = model.blob.get_repo_blob_by_digest(namespace_name, repo_name, digest)
      return Blob(
        id=blob_record.id,
        uuid=blob_record.uuid,
        digest=digest,
        size=blob_record.image_size,
        locations=list(blob_record.locations),
        cas_path=blob_record.cas_path
      )
    except model.BlobDoesNotExist:
      return None

  def save_bittorrent_pieces(self, blob, piece_size, piece_bytes):
    blob_record = model.storage.get_storage_by_uuid(blob.uuid)
    model.storage.save_torrent_info(blob_record, piece_size, piece_bytes)

  def create_manifest_labels(self, namespace_name, repo_name, manifest_digest, labels):
    if not labels:
      # No point in doing anything more.
      return

    tag_manifest = model.tag.load_manifest_by_digest(namespace_name, repo_name, manifest_digest)
    for label in labels:
      model.label.create_manifest_label(tag_manifest, label.key, label.value, label.source_type,
                                        label.media_type)

  def get_blob_path(self, blob):
    return model.storage.get_layer_path_for_storage(blob.uuid, blob.cas_path, blob.digest)

  def set_manifest_expires_after(self, namespace_name, repo_name, digest, expires_after_sec):
    try:
      manifest = model.tag.load_manifest_by_digest(namespace_name, repo_name, digest)
      manifest.tag.lifetime_end_ts = manifest.tag.lifetime_start_ts + expires_after_sec
      manifest.tag.save()
    except model.InvalidManifestException:
      return

  def is_namespace_enabled(self, namespace_name):
    namespace = model.user.get_namespace_user(namespace_name)
    return namespace is None or namespace.enabled


def _docker_v1_metadata(namespace_name, repo_name, repo_image):
  """
  Returns a DockerV1Metadata object for the given Pre-OCI repo_image under the
  repository with the given namespace and name. Note that the namespace and
  name are passed here as an optimization, and are *not checked* against the
  image.
  """
  return DockerV1Metadata(
    namespace_name=namespace_name,
    repo_name=repo_name,
    image_id=repo_image.docker_image_id,
    checksum=repo_image.v1_checksum,
    content_checksum=repo_image.storage.content_checksum,
    compat_json=repo_image.v1_json_metadata,
    created=repo_image.created,
    comment=repo_image.comment,
    command=repo_image.command,
    # TODO: make sure this isn't needed anywhere, as it is expensive to lookup
    parent_image_id=None,
  )


def _repository_for_repo(repo):
  """ Returns a Repository object representing the Pre-OCI data model repo instance given. """
  return Repository(
    id=repo.id,
    name=repo.name,
    namespace_name=repo.namespace_user.username,
    description=repo.description,
    is_public=model.repository.is_repository_public(repo),
    kind=model.repository.get_repo_kind_name(repo),
    trust_enabled=repo.trust_enabled,)


data_model = PreOCIModel()