""" Manage the manifests of a repository. """
import json
import logging

from flask import request

from app import label_validator, storage
from data.model import InvalidLabelKeyException, InvalidMediaTypeException
from data.registry_model import registry_model
from digest import digest_tools
from endpoints.api import (resource, nickname, require_repo_read, require_repo_write,
                           RepositoryParamResource, log_action, validate_json_request,
                           path_param, parse_args, query_param, abort, api,
                           disallow_for_app_repositories, format_date)
from endpoints.api.image import image_dict
from endpoints.exception import NotFound
from util.validation import VALID_LABEL_KEY_REGEX


BASE_MANIFEST_ROUTE = '/v1/repository/<apirepopath:repository>/manifest/<regex("{0}"):manifestref>'
MANIFEST_DIGEST_ROUTE = BASE_MANIFEST_ROUTE.format(digest_tools.DIGEST_PATTERN)
ALLOWED_LABEL_MEDIA_TYPES = ['text/plain', 'application/json']


logger = logging.getLogger(__name__)

def _label_dict(label):
  return {
    'id': label.uuid,
    'key': label.key,
    'value': label.value,
    'source_type': label.source_type_name,
    'media_type': label.media_type_name,
  }


def _layer_dict(manifest_layer, index):
  # NOTE: The `command` in the layer is either a JSON string of an array (schema 1) or
  # a single string (schema 2). The block below normalizes it to have the same format.
  command = None
  if manifest_layer.command:
    try:
      command = json.loads(manifest_layer.command)
    except (TypeError, ValueError):
      command = [manifest_layer.command]

  return {
    'index': index,
    'compressed_size': manifest_layer.compressed_size,
    'is_remote': manifest_layer.is_remote,
    'urls': manifest_layer.urls,
    'command': command,
    'comment': manifest_layer.comment,
    'author': manifest_layer.author,
    'blob_digest': str(manifest_layer.blob_digest),
    'created_datetime': format_date(manifest_layer.created_datetime),
  }


def _manifest_dict(manifest):
  image = None
  if manifest.legacy_image_if_present is not None:
    image = image_dict(manifest.legacy_image, with_history=True)

  layers = None
  if not manifest.is_manifest_list:
    layers = registry_model.list_manifest_layers(manifest, storage)
    if layers is None:
      logger.debug('Missing layers for manifest `%s`', manifest.digest)
      abort(404)

  return {
    'digest': manifest.digest,
    'is_manifest_list': manifest.is_manifest_list,
    'manifest_data': manifest.internal_manifest_bytes.as_unicode(),
    'image': image,
    'layers': ([_layer_dict(lyr.layer_info, idx) for idx, lyr in enumerate(layers)]
               if layers else None),
  }


@resource(MANIFEST_DIGEST_ROUTE)
@path_param('repository', 'The full path of the repository. e.g. namespace/name')
@path_param('manifestref', 'The digest of the manifest')
class RepositoryManifest(RepositoryParamResource):
  """ Resource for retrieving a specific repository manifest. """
  @require_repo_read
  @nickname('getRepoManifest')
  @disallow_for_app_repositories
  def get(self, namespace_name, repository_name, manifestref):
    repo_ref = registry_model.lookup_repository(namespace_name, repository_name)
    if repo_ref is None:
      raise NotFound()

    manifest = registry_model.lookup_manifest_by_digest(repo_ref, manifestref,
                                                        include_legacy_image=True)
    if manifest is None:
      raise NotFound()

    return _manifest_dict(manifest)


@resource(MANIFEST_DIGEST_ROUTE + '/labels')
@path_param('repository', 'The full path of the repository. e.g. namespace/name')
@path_param('manifestref', 'The digest of the manifest')
class RepositoryManifestLabels(RepositoryParamResource):
  """ Resource for listing the labels on a specific repository manifest. """
  schemas = {
    'AddLabel': {
      'type': 'object',
      'description': 'Adds a label to a manifest',
      'required': [
        'key',
        'value',
        'media_type',
      ],
      'properties': {
        'key': {
          'type': 'string',
          'description': 'The key for the label',
        },
        'value': {
          'type': 'string',
          'description': 'The value for the label',
        },
        'media_type': {
          'type': ['string', 'null'],
          'description': 'The media type for this label',
          'enum': ALLOWED_LABEL_MEDIA_TYPES + [None],
        },
      },
    },
  }

  @require_repo_read
  @nickname('listManifestLabels')
  @disallow_for_app_repositories
  @parse_args()
  @query_param('filter', 'If specified, only labels matching the given prefix will be returned',
               type=str, default=None)
  def get(self, namespace_name, repository_name, manifestref, parsed_args):
    repo_ref = registry_model.lookup_repository(namespace_name, repository_name)
    if repo_ref is None:
      raise NotFound()

    manifest = registry_model.lookup_manifest_by_digest(repo_ref, manifestref)
    if manifest is None:
      raise NotFound()

    labels = registry_model.list_manifest_labels(manifest, parsed_args['filter'])
    if labels is None:
      raise NotFound()

    return {
      'labels': [_label_dict(label) for label in labels]
    }

  @require_repo_write
  @nickname('addManifestLabel')
  @disallow_for_app_repositories
  @validate_json_request('AddLabel')
  def post(self, namespace_name, repository_name, manifestref):
    """ Adds a new label into the tag manifest. """
    label_data = request.get_json()

    # Check for any reserved prefixes.
    if label_validator.has_reserved_prefix(label_data['key']):
      abort(400, message='Label has a reserved prefix')

    repo_ref = registry_model.lookup_repository(namespace_name, repository_name)
    if repo_ref is None:
      raise NotFound()

    manifest = registry_model.lookup_manifest_by_digest(repo_ref, manifestref)
    if manifest is None:
      raise NotFound()

    label = None
    try:
      label = registry_model.create_manifest_label(manifest,
                                                   label_data['key'],
                                                   label_data['value'],
                                                   'api',
                                                   label_data['media_type'])
    except InvalidLabelKeyException:
      message = ('Label is of an invalid format or missing please ' +
                 'use %s format for labels' % VALID_LABEL_KEY_REGEX)
      abort(400, message=message)
    except InvalidMediaTypeException:
      message = 'Media type is invalid please use a valid media type: text/plain, application/json'
      abort(400, message=message)

    if label is None:
      raise NotFound()

    metadata = {
      'id': label.uuid,
      'key': label.key,
      'value': label.value,
      'manifest_digest': manifestref,
      'media_type': label.media_type_name,
      'namespace': namespace_name,
      'repo': repository_name,
    }

    log_action('manifest_label_add', namespace_name, metadata, repo_name=repository_name)

    resp = {'label': _label_dict(label)}
    repo_string = '%s/%s' % (namespace_name, repository_name)
    headers = {
      'Location': api.url_for(ManageRepositoryManifestLabel, repository=repo_string,
                              manifestref=manifestref, labelid=label.uuid),
    }
    return resp, 201, headers


@resource(MANIFEST_DIGEST_ROUTE + '/labels/<labelid>')
@path_param('repository', 'The full path of the repository. e.g. namespace/name')
@path_param('manifestref', 'The digest of the manifest')
@path_param('labelid', 'The ID of the label')
class ManageRepositoryManifestLabel(RepositoryParamResource):
  """ Resource for managing the labels on a specific repository manifest. """
  @require_repo_read
  @nickname('getManifestLabel')
  @disallow_for_app_repositories
  def get(self, namespace_name, repository_name, manifestref, labelid):
    """ Retrieves the label with the specific ID under the manifest. """
    repo_ref = registry_model.lookup_repository(namespace_name, repository_name)
    if repo_ref is None:
      raise NotFound()

    manifest = registry_model.lookup_manifest_by_digest(repo_ref, manifestref)
    if manifest is None:
      raise NotFound()

    label = registry_model.get_manifest_label(manifest, labelid)
    if label is None:
      raise NotFound()

    return _label_dict(label)


  @require_repo_write
  @nickname('deleteManifestLabel')
  @disallow_for_app_repositories
  def delete(self, namespace_name, repository_name, manifestref, labelid):
    """ Deletes an existing label from a manifest. """
    repo_ref = registry_model.lookup_repository(namespace_name, repository_name)
    if repo_ref is None:
      raise NotFound()

    manifest = registry_model.lookup_manifest_by_digest(repo_ref, manifestref)
    if manifest is None:
      raise NotFound()

    deleted = registry_model.delete_manifest_label(manifest, labelid)
    if deleted is None:
      raise NotFound()

    metadata = {
      'id': labelid,
      'key': deleted.key,
      'value': deleted.value,
      'manifest_digest': manifestref,
      'namespace': namespace_name,
      'repo': repository_name,
    }

    log_action('manifest_label_delete', namespace_name, metadata, repo_name=repository_name)
    return '', 204