import logging
from base64 import b64encode

import cnr
from cnr.api.impl import registry as cnr_registry
from cnr.api.registry import _pull, repo_name
from cnr.exception import (
  ChannelNotFound, CnrException, Forbidden, InvalidParams, InvalidRelease, InvalidUsage,
  PackageAlreadyExists, PackageNotFound, PackageReleaseNotFound, UnableToLockResource,
  UnauthorizedAccess, Unsupported)
from flask import jsonify, request

from auth.auth_context import get_authenticated_user
from auth.credentials import validate_credentials
from auth.decorators import process_auth
from auth.permissions import CreateRepositoryPermission, ModifyRepositoryPermission
from endpoints.appr import appr_bp, require_app_repo_read, require_app_repo_write
from endpoints.appr.cnr_backend import Blob, Channel, Package, User
from endpoints.appr.decorators import disallow_for_image_repository
from endpoints.appr.models_cnr import model
from endpoints.decorators import anon_allowed, anon_protect, check_region_blacklisted
from util.names import REPOSITORY_NAME_REGEX, TAG_REGEX

logger = logging.getLogger(__name__)


@appr_bp.errorhandler(Unsupported)
@appr_bp.errorhandler(PackageAlreadyExists)
@appr_bp.errorhandler(InvalidRelease)
@appr_bp.errorhandler(Forbidden)
@appr_bp.errorhandler(UnableToLockResource)
@appr_bp.errorhandler(UnauthorizedAccess)
@appr_bp.errorhandler(PackageNotFound)
@appr_bp.errorhandler(PackageReleaseNotFound)
@appr_bp.errorhandler(CnrException)
@appr_bp.errorhandler(InvalidUsage)
@appr_bp.errorhandler(InvalidParams)
@appr_bp.errorhandler(ChannelNotFound)
def render_error(error):
  response = jsonify({"error": error.to_dict()})
  response.status_code = error.status_code
  return response


@appr_bp.route("/version")
@anon_allowed
def version():
  return jsonify({"cnr-api": cnr.__version__})


@appr_bp.route("/api/v1/users/login", methods=['POST'])
@anon_allowed
def login():
  values = request.get_json(force=True, silent=True) or {}
  username = values.get('user', {}).get('username')
  password = values.get('user', {}).get('password')
  if not username or not password:
    raise InvalidUsage('Missing username or password')

  result, _ = validate_credentials(username, password)
  if not result.auth_valid:
    raise UnauthorizedAccess(result.error_message)

  return jsonify({'token': "basic " + b64encode("%s:%s" % (username, password))})


# @TODO: Redirect to S3 url
@appr_bp.route(
  "/api/v1/packages/<string:namespace>/<string:package_name>/blobs/sha256/<string:digest>",
  methods=['GET'],
  strict_slashes=False,)
@process_auth
@require_app_repo_read
@check_region_blacklisted(namespace_name_kwarg='namespace')
@anon_protect
def blobs(namespace, package_name, digest):
  reponame = repo_name(namespace, package_name)
  data = cnr_registry.pull_blob(reponame, digest, blob_class=Blob)
  json_format = request.args.get('format', None) == 'json'
  return _pull(data, json_format=json_format)


@appr_bp.route("/api/v1/packages", methods=['GET'], strict_slashes=False)
@process_auth
@anon_protect
def list_packages():
  namespace = request.args.get('namespace', None)
  media_type = request.args.get('media_type', None)
  query = request.args.get('query', None)
  user = get_authenticated_user()
  username = None
  if user:
    username = user.username
  result_data = cnr_registry.list_packages(namespace, package_class=Package, search=query,
                                           media_type=media_type, username=username)
  return jsonify(result_data)


@appr_bp.route(
  "/api/v1/packages/<string:namespace>/<string:package_name>/<string:release>/<string:media_type>",
  methods=['DELETE'], strict_slashes=False)
@process_auth
@require_app_repo_write
@anon_protect
def delete_package(namespace, package_name, release, media_type):
  reponame = repo_name(namespace, package_name)
  result = cnr_registry.delete_package(reponame, release, media_type, package_class=Package)
  model.log_action('delete_tag', namespace, repo_name=package_name,
                   metadata={'release': release, 'mediatype': media_type})
  return jsonify(result)


@appr_bp.route(
  "/api/v1/packages/<string:namespace>/<string:package_name>/<string:release>/<string:media_type>",
  methods=['GET'], strict_slashes=False)
@process_auth
@require_app_repo_read
@check_region_blacklisted(namespace_name_kwarg='namespace')
@anon_protect
def show_package(namespace, package_name, release, media_type):
  reponame = repo_name(namespace, package_name)
  result = cnr_registry.show_package(reponame, release, media_type, channel_class=Channel,
                                     package_class=Package)
  return jsonify(result)


@appr_bp.route("/api/v1/packages/<string:namespace>/<string:package_name>", methods=['GET'],
               strict_slashes=False)
@process_auth
@require_app_repo_read
@anon_protect
def show_package_releases(namespace, package_name):
  reponame = repo_name(namespace, package_name)
  media_type = request.args.get('media_type', None)
  result = cnr_registry.show_package_releases(reponame, media_type=media_type,
                                              package_class=Package)
  return jsonify(result)


@appr_bp.route("/api/v1/packages/<string:namespace>/<string:package_name>/<string:release>",
               methods=['GET'], strict_slashes=False)
@process_auth
@require_app_repo_read
@anon_protect
def show_package_release_manifests(namespace, package_name, release):
  reponame = repo_name(namespace, package_name)
  result = cnr_registry.show_package_manifests(reponame, release, package_class=Package)
  return jsonify(result)


@appr_bp.route(
  "/api/v1/packages/<string:namespace>/<string:package_name>/<string:release>/<string:media_type>/pull",
  methods=['GET'],
  strict_slashes=False,)
@process_auth
@require_app_repo_read
@check_region_blacklisted(namespace_name_kwarg='namespace')
@anon_protect
def pull(namespace, package_name, release, media_type):
  logger.debug('Pull of release %s of app repository %s/%s', release, namespace, package_name)
  reponame = repo_name(namespace, package_name)
  data = cnr_registry.pull(reponame, release, media_type, Package, blob_class=Blob)
  model.log_action('pull_repo', namespace, repo_name=package_name,
                   metadata={'release': release, 'mediatype': media_type})
  json_format = request.args.get('format', None) == 'json'
  return _pull(data, json_format)


@appr_bp.route("/api/v1/packages/<string:namespace>/<string:package_name>", methods=['POST'],
               strict_slashes=False)
@disallow_for_image_repository()
@process_auth
@anon_protect
def push(namespace, package_name):
  reponame = repo_name(namespace, package_name)

  if not REPOSITORY_NAME_REGEX.match(package_name):
    logger.debug('Found invalid repository name CNR push: %s', reponame)
    raise InvalidUsage('invalid repository name: %s' % reponame)

  values = request.get_json(force=True, silent=True) or {}
  private = values.get('visibility', 'private')

  owner = get_authenticated_user()
  if not Package.exists(reponame):
    if not CreateRepositoryPermission(namespace).can():
      raise Forbidden("Unauthorized access for: %s" % reponame,
                      {"package": reponame,
                       "scopes": ['create']})
    Package.create_repository(reponame, private, owner)
    model.log_action('create_repo', namespace, repo_name=package_name)

  if not ModifyRepositoryPermission(namespace, package_name).can():
    raise Forbidden("Unauthorized access for: %s" % reponame,
                    {"package": reponame,
                     "scopes": ['push']})

  if not 'release' in values:
    raise InvalidUsage('Missing release')

  if not 'media_type' in values:
    raise InvalidUsage('Missing media_type')

  if not 'blob' in values:
    raise InvalidUsage('Missing blob')

  release_version = str(values['release'])
  media_type = values['media_type']
  force = request.args.get('force', 'false') == 'true'

  blob = Blob(reponame, values['blob'])
  app_release = cnr_registry.push(reponame, release_version, media_type, blob, force,
                                  package_class=Package, user=owner, visibility=private)
  model.log_action('push_repo', namespace, repo_name=package_name,
                   metadata={'release': release_version})
  return jsonify(app_release)


@appr_bp.route("/api/v1/packages/search", methods=['GET'], strict_slashes=False)
@process_auth
@anon_protect
def search_packages():
  query = request.args.get("q")
  user = get_authenticated_user()
  username = None
  if user:
    username = user.username

  search_results = cnr_registry.search(query, Package, username=username)
  return jsonify(search_results)


# CHANNELS
@appr_bp.route("/api/v1/packages/<string:namespace>/<string:package_name>/channels",
               methods=['GET'], strict_slashes=False)
@process_auth
@require_app_repo_read
@anon_protect
def list_channels(namespace, package_name):
  reponame = repo_name(namespace, package_name)
  return jsonify(cnr_registry.list_channels(reponame, channel_class=Channel))


@appr_bp.route(
  "/api/v1/packages/<string:namespace>/<string:package_name>/channels/<string:channel_name>",
  methods=['GET'], strict_slashes=False)
@process_auth
@require_app_repo_read
@anon_protect
def show_channel(namespace, package_name, channel_name):
  reponame = repo_name(namespace, package_name)
  channel = cnr_registry.show_channel(reponame, channel_name, channel_class=Channel)
  return jsonify(channel)


@appr_bp.route(
  "/api/v1/packages/<string:namespace>/<string:package_name>/channels/<string:channel_name>/<string:release>",
  methods=['POST'],
  strict_slashes=False,)
@process_auth
@require_app_repo_write
@anon_protect
def add_channel_release(namespace, package_name, channel_name, release):
  _check_channel_name(channel_name, release)
  reponame = repo_name(namespace, package_name)
  result = cnr_registry.add_channel_release(reponame, channel_name, release, channel_class=Channel,
                                            package_class=Package)
  model.log_action('create_tag', namespace, repo_name=package_name,
                   metadata={'channel': channel_name, 'release': release})
  return jsonify(result)


def _check_channel_name(channel_name, release=None):
  if not TAG_REGEX.match(channel_name):
    logger.debug('Found invalid channel name CNR add channel release: %s', channel_name)
    raise InvalidUsage("Found invalid channelname %s" % release,
                       {'name': channel_name,
                        'release': release})

  if release is not None and not TAG_REGEX.match(release):
    logger.debug('Found invalid release name CNR add channel release: %s', release)
    raise InvalidUsage('Found invalid channel release name %s' % release,
                       {'name': channel_name,
                        'release': release})


@appr_bp.route(
  "/api/v1/packages/<string:namespace>/<string:package_name>/channels/<string:channel_name>/<string:release>",
  methods=['DELETE'],
  strict_slashes=False,)
@process_auth
@require_app_repo_write
@anon_protect
def delete_channel_release(namespace, package_name, channel_name, release):
  _check_channel_name(channel_name, release)
  reponame = repo_name(namespace, package_name)
  result = cnr_registry.delete_channel_release(reponame, channel_name, release,
                                               channel_class=Channel, package_class=Package)
  model.log_action('delete_tag', namespace, repo_name=package_name,
                   metadata={'channel': channel_name, 'release': release})
  return jsonify(result)


@appr_bp.route(
  "/api/v1/packages/<string:namespace>/<string:package_name>/channels/<string:channel_name>",
  methods=['DELETE'],
  strict_slashes=False,)
@process_auth
@require_app_repo_write
@anon_protect
def delete_channel(namespace, package_name, channel_name):
  _check_channel_name(channel_name)
  reponame = repo_name(namespace, package_name)
  result = cnr_registry.delete_channel(reponame, channel_name, channel_class=Channel)
  model.log_action('delete_tag', namespace, repo_name=package_name,
                   metadata={'channel': channel_name})
  return jsonify(result)