""" List, create and manage repositories. """

import logging
import datetime
import features

from datetime import timedelta, datetime

from flask import request, abort

from data import model
from data.database import Repository as RepositoryTable
from endpoints.api import (truthy_bool, format_date, nickname, log_action, validate_json_request,
                           require_repo_read, require_repo_write, require_repo_admin,
                           RepositoryParamResource, resource, query_param, parse_args, ApiResource,
                           request_error, require_scope, path_param, page_support, parse_args,
                           query_param, truthy_bool)
from endpoints.exception import Unauthorized, NotFound, InvalidRequest, ExceedsLicenseException
from endpoints.api.billing import lookup_allowed_private_repos, get_namespace_plan
from endpoints.api.subscribe import check_repository_usage

from auth.permissions import (ModifyRepositoryPermission, AdministerRepositoryPermission,
                              CreateRepositoryPermission, ReadRepositoryPermission)
from auth.auth_context import get_authenticated_user
from auth import scopes
from util.names import REPOSITORY_NAME_REGEX


logger = logging.getLogger(__name__)

REPOS_PER_PAGE = 100
MAX_DAYS_IN_3_MONTHS = 92

def check_allowed_private_repos(namespace):
  """ Checks to see if the given namespace has reached its private repository limit. If so,
      raises a ExceedsLicenseException.
  """
  # Not enabled if billing is disabled.
  if not features.BILLING:
    return

  if not lookup_allowed_private_repos(namespace):
    raise ExceedsLicenseException()


@resource('/v1/repository')
class RepositoryList(ApiResource):
  """Operations for creating and listing repositories."""
  schemas = {
    'NewRepo': {
      'type': 'object',
      'description': 'Description of a new repository',
      'required': [
        'repository',
        'visibility',
        'description',
      ],
      'properties': {
        'repository': {
          'type': 'string',
          'description': 'Repository name',
        },
        'visibility': {
          'type': 'string',
          'description': 'Visibility which the repository will start with',
          'enum': [
            'public',
            'private',
          ],
        },
        'namespace': {
          'type': 'string',
          'description': ('Namespace in which the repository should be created. If omitted, the '
                          'username of the caller is used'),
        },
        'description': {
          'type': 'string',
          'description': 'Markdown encoded description for the repository',
        },
      },
    },
  }

  @require_scope(scopes.CREATE_REPO)
  @nickname('createRepo')
  @validate_json_request('NewRepo')
  def post(self):
    """Create a new repository."""
    owner = get_authenticated_user()
    req = request.get_json()

    if owner is None and 'namespace' not in 'req':
      raise InvalidRequest('Must provide a namespace or must be logged in.')

    namespace_name = req['namespace'] if 'namespace' in req else owner.username

    permission = CreateRepositoryPermission(namespace_name)
    if permission.can():
      repository_name = req['repository']
      visibility = req['visibility']

      existing = model.repository.get_repository(namespace_name, repository_name)
      if existing:
        raise request_error(message='Repository already exists')

      visibility = req['visibility']
      if visibility == 'private':
        check_allowed_private_repos(namespace_name)

      # Verify that the repository name is valid.
      if not REPOSITORY_NAME_REGEX.match(repository_name):
        raise InvalidRequest('Invalid repository name')

      repo = model.repository.create_repository(namespace_name, repository_name, owner, visibility)
      repo.description = req['description']
      repo.save()

      log_action('create_repo', namespace_name, {'repo': repository_name,
                                                 'namespace': namespace_name}, repo=repo)
      return {
        'namespace': namespace_name,
        'name': repository_name
      }, 201

    raise Unauthorized()


  @require_scope(scopes.READ_REPO)
  @nickname('listRepos')
  @parse_args()
  @query_param('namespace', 'Filters the repositories returned to this namespace', type=str)
  @query_param('starred', 'Filters the repositories returned to those starred by the user',
               type=truthy_bool, default=False)
  @query_param('public', 'Adds any repositories visible to the user by virtue of being public',
               type=truthy_bool, default=False)
  @query_param('last_modified', 'Whether to include when the repository was last modified.',
               type=truthy_bool, default=False)
  @query_param('popularity', 'Whether to include the repository\'s popularity metric.',
               type=truthy_bool, default=False)
  @page_support()
  def get(self, page_token, parsed_args):
    """ Fetch the list of repositories visible to the current user under a variety of situations.
    """
    # Ensure that the user requests either filtered by a namespace, only starred repositories,
    # or public repositories. This ensures that the user is not requesting *all* visible repos,
    # which can cause a surge in DB CPU usage.
    if not parsed_args['namespace'] and not parsed_args['starred'] and not parsed_args['public']:
      raise InvalidRequest('namespace, starred or public are required for this API call')

    user = get_authenticated_user()
    username = user.username if user else None
    next_page_token = None
    repos = None

    # Lookup the requested repositories (either starred or non-starred.)
    if parsed_args['starred']:
      if not username:
        # No repositories should be returned, as there is no user.
        abort(400)

      # Return the full list of repos starred by the current user that are still visible to them.
      def can_view_repo(repo):
        return ReadRepositoryPermission(repo.namespace_user.username, repo.name).can()

      unfiltered_repos = model.repository.get_user_starred_repositories(user)
      repos = [repo for repo in unfiltered_repos if can_view_repo(repo)]
    elif parsed_args['namespace']:
      # Repositories filtered by namespace do not need pagination (their results are fairly small),
      # so we just do the lookup directly.
      repos = list(model.repository.get_visible_repositories(username=username,
                                                             include_public=parsed_args['public'],
                                                             namespace=parsed_args['namespace']))
    else:
      # Determine the starting offset for pagination. Note that we don't use the normal
      # model.modelutil.paginate method here, as that does not operate over UNION queries, which
      # get_visible_repositories will return if there is a logged-in user (for performance reasons).
      #
      # Also note the +1 on the limit, as paginate_query uses the extra result to determine whether
      # there is a next page.
      start_id = model.modelutil.pagination_start(page_token)
      repo_query = model.repository.get_visible_repositories(username=username,
                                                             include_public=parsed_args['public'],
                                                             start_id=start_id,
                                                             limit=REPOS_PER_PAGE+1)

      repos, next_page_token = model.modelutil.paginate_query(repo_query, limit=REPOS_PER_PAGE,
                                                              id_alias='rid')

    # Collect the IDs of the repositories found for subequent lookup of popularity
    # and/or last modified.
    if parsed_args['last_modified'] or parsed_args['popularity']:
      repository_ids = [repo.rid for repo in repos]

      if parsed_args['last_modified']:
        last_modified_map = model.repository.get_when_last_modified(repository_ids)

      if parsed_args['popularity']:
        action_sum_map = model.log.get_repositories_action_sums(repository_ids)

    # Collect the IDs of the repositories that are starred for the user, so we can mark them
    # in the returned results.
    star_set = set()
    if username:
      starred_repos = model.repository.get_user_starred_repositories(user)
      star_set = {starred.id for starred in starred_repos}

    def repo_view(repo_obj):
      repo = {
        'namespace': repo_obj.namespace_user.username,
        'name': repo_obj.name,
        'description': repo_obj.description,
        'is_public': repo_obj.visibility_id == model.repository.get_public_repo_visibility().id,
      }

      repo_id = repo_obj.rid

      if parsed_args['last_modified']:
        repo['last_modified'] = last_modified_map.get(repo_id)

      if parsed_args['popularity']:
        repo['popularity'] = action_sum_map.get(repo_id, 0)

      if username:
        repo['is_starred'] = repo_id in star_set

      return repo

    return {
      'repositories': [repo_view(repo) for repo in repos]
    }, next_page_token


@resource('/v1/repository/<apirepopath:repository>')
@path_param('repository', 'The full path of the repository. e.g. namespace/name')
class Repository(RepositoryParamResource):
  """Operations for managing a specific repository."""
  schemas = {
    'RepoUpdate': {
      'type': 'object',
      'description': 'Fields which can be updated in a repository.',
      'required': [
        'description',
      ],
      'properties': {
        'description': {
          'type': 'string',
          'description': 'Markdown encoded description for the repository',
        },
      }
    }
  }

  @parse_args()
  @query_param('includeStats', 'Whether to include action statistics', type=truthy_bool,
               default=False)
  @require_repo_read
  @nickname('getRepo')
  def get(self, namespace, repository, parsed_args):
    """Fetch the specified repository."""
    logger.debug('Get repo: %s/%s' % (namespace, repository))

    def tag_view(tag):
      tag_info = {
        'name': tag.name,
        'image_id': tag.image.docker_image_id,
        'size': tag.image.aggregate_size
      }

      if tag.lifetime_start_ts > 0:
        last_modified = format_date(datetime.fromtimestamp(tag.lifetime_start_ts))
        tag_info['last_modified'] = last_modified

      return tag_info

    repo = model.repository.get_repository(namespace, repository)
    stats = None
    if repo:
      tags = model.tag.list_repository_tags(namespace, repository, include_storage=True)
      tag_dict = {tag.name: tag_view(tag) for tag in tags}
      can_write = ModifyRepositoryPermission(namespace, repository).can()
      can_admin = AdministerRepositoryPermission(namespace, repository).can()

      is_starred = (model.repository.repository_is_starred(get_authenticated_user(), repo)
                    if get_authenticated_user() else False)
      is_public = model.repository.is_repository_public(repo)

      if parsed_args['includeStats']:
        stats = []
        found_dates = {}

        start_date = datetime.now() - timedelta(days=MAX_DAYS_IN_3_MONTHS)
        counts = model.log.get_repository_action_counts(repo, start_date)
        for count in counts:
          stats.append({
            'date': count.date.isoformat(),
            'count': count.count,
          })

          found_dates['%s/%s' % (count.date.month, count.date.day)] = True

        # Fill in any missing stats with zeros.
        for day in range(1, MAX_DAYS_IN_3_MONTHS):
          day_date = datetime.now() - timedelta(days=day)
          key = '%s/%s' % (day_date.month, day_date.day)
          if not key in found_dates:
            stats.append({
              'date': day_date.date().isoformat(),
              'count': 0,
            })

      repo_data = {
        'namespace': namespace,
        'name': repository,
        'description': repo.description,
        'tags': tag_dict,
        'can_write': can_write,
        'can_admin': can_admin,
        'is_public': is_public,
        'is_organization': repo.namespace_user.organization,
        'is_starred': is_starred,
        'status_token': repo.badge_token if not is_public else '',
      }

      if stats is not None:
        repo_data['stats'] = stats

      return repo_data

    raise NotFound()

  @require_repo_write
  @nickname('updateRepo')
  @validate_json_request('RepoUpdate')
  def put(self, namespace, repository):
    """ Update the description in the specified repository. """
    repo = model.repository.get_repository(namespace, repository)
    if repo:
      values = request.get_json()
      repo.description = values['description']
      repo.save()

      log_action('set_repo_description', namespace,
                 {'repo': repository, 'description': values['description']},
                 repo=repo)
      return {
          'success': True
      }
    raise NotFound()

  @require_repo_admin
  @nickname('deleteRepository')
  def delete(self, namespace, repository):
    """ Delete a repository. """
    model.repository.purge_repository(namespace, repository)
    user = model.user.get_namespace_user(namespace)
    if features.BILLING:
      plan = get_namespace_plan(namespace)
      check_repository_usage(user, plan)
    log_action('delete_repo', namespace,
               {'repo': repository, 'namespace': namespace})
    return 'Deleted', 204


@resource('/v1/repository/<apirepopath:repository>/changevisibility')
@path_param('repository', 'The full path of the repository. e.g. namespace/name')
class RepositoryVisibility(RepositoryParamResource):
  """ Custom verb for changing the visibility of the repository. """
  schemas = {
    'ChangeVisibility': {
      'type': 'object',
      'description': 'Change the visibility for the repository.',
      'required': [
        'visibility',
      ],
      'properties': {
        'visibility': {
          'type': 'string',
          'description': 'Visibility which the repository will start with',
          'enum': [
            'public',
            'private',
          ],
        },
      }
    }
  }

  @require_repo_admin
  @nickname('changeRepoVisibility')
  @validate_json_request('ChangeVisibility')
  def post(self, namespace, repository):
    """ Change the visibility of a repository. """
    repo = model.repository.get_repository(namespace, repository)
    if repo:
      values = request.get_json()
      visibility = values['visibility']
      if visibility == 'private':
        check_allowed_private_repos(namespace)

      model.repository.set_repository_visibility(repo, visibility)
      log_action('change_repo_visibility', namespace,
                 {'repo': repository, 'visibility': values['visibility']},
                 repo=repo)
      return {'success': True}