import copy
import logging.config
import json
import os
import shutil

from tempfile import NamedTemporaryFile

import pytest

from Crypto import Random
from flask import jsonify, g
from flask_principal import Identity

from app import storage
from data.database import close_db_filter, configure, DerivedStorageForImage, QueueItem, Image
from data import model
from endpoints.csrf import generate_csrf_token
from util.log import logfile_path

from test.registry.liveserverfixture import LiveServerExecutor


@pytest.fixture()
def registry_server_executor(app):
  def generate_csrf():
    return generate_csrf_token()

  def set_supports_direct_download(enabled):
    storage.put_content(['local_us'], 'supports_direct_download', 'true' if enabled else 'false')
    return 'OK'

  def delete_image(image_id):
    image = Image.get(docker_image_id=image_id)
    image.docker_image_id = 'DELETED'
    image.save()
    return 'OK'

  def get_storage_replication_entry(image_id):
    image = Image.get(docker_image_id=image_id)
    QueueItem.select().where(QueueItem.queue_name ** ('%' + image.storage.uuid + '%')).get()
    return 'OK'

  def set_feature(feature_name, value):
    import features
    old_value = features._FEATURES[feature_name].value
    features._FEATURES[feature_name].value = value
    return jsonify({'old_value': old_value})

  def clear_derived_cache():
    DerivedStorageForImage.delete().execute()
    return 'OK'

  def clear_uncompressed_size(image_id):
    image = model.image.get_image_by_id('devtable', 'newrepo', image_id)
    image.storage.uncompressed_size = None
    image.storage.save()
    return 'OK'

  def add_token():
    another_token = model.token.create_delegate_token('devtable', 'newrepo', 'my-new-token',
                                                      'write')
    another_token.code = 'somecooltokencode'
    another_token.save()
    return another_token.code

  def break_database():
    # Close any existing connection.
    close_db_filter(None)

    # Reload the database config with an invalid connection.
    config = copy.copy(app.config)
    config['DB_URI'] = 'sqlite:///not/a/valid/database'
    configure(config)

    return 'OK'

  def reload_app(server_hostname):
    # Close any existing connection.
    close_db_filter(None)

    # Reload the database config.
    app.config['SERVER_HOSTNAME'] = server_hostname[len('http://'):]
    configure(app.config)

    # Reload random after the process split, as it cannot be used uninitialized across forks.
    Random.atfork()

    # Required for anonymous calls to not exception.
    g.identity = Identity(None, 'none')

    if os.environ.get('DEBUGLOG') == 'true':
      logging.config.fileConfig(logfile_path(debug=True), disable_existing_loggers=False)

    return 'OK'

  def create_app_repository(namespace, name):
    user = model.user.get_user(namespace)
    model.repository.create_repository(namespace, name, user, repo_kind='application')
    return 'OK'

  def disable_namespace(namespace):
    namespace_obj = model.user.get_namespace_user(namespace)
    namespace_obj.enabled = False
    namespace_obj.save()
    return 'OK'

  executor = LiveServerExecutor()
  executor.register('generate_csrf', generate_csrf)
  executor.register('set_supports_direct_download', set_supports_direct_download)
  executor.register('delete_image', delete_image)
  executor.register('get_storage_replication_entry', get_storage_replication_entry)
  executor.register('set_feature', set_feature)
  executor.register('clear_derived_cache', clear_derived_cache)
  executor.register('clear_uncompressed_size', clear_uncompressed_size)
  executor.register('add_token', add_token)
  executor.register('break_database', break_database)
  executor.register('reload_app', reload_app)
  executor.register('create_app_repository', create_app_repository)
  executor.register('disable_namespace', disable_namespace)
  return executor


@pytest.fixture()
def liveserver_app(app, registry_server_executor, init_db_path):
  registry_server_executor.apply_blueprint_to_app(app)

  if os.environ.get('DEBUG', 'false').lower() == 'true':
    app.config['DEBUG'] = True

  # Copy the clean database to a new path. We cannot share the DB created by the
  # normal app fixture, as it is already open in the local process.
  local_db_file = NamedTemporaryFile(delete=True)
  local_db_file.close()

  shutil.copy2(init_db_path, local_db_file.name)
  app.config['DB_URI'] = 'sqlite:///{0}'.format(local_db_file.name)
  return app


@pytest.fixture()
def app_reloader(liveserver, registry_server_executor):
  registry_server_executor.on(liveserver).reload_app(liveserver.url)
  yield


class FeatureFlagValue(object):
  """ Helper object which temporarily sets the value of a feature flag.

      Usage:

      with FeatureFlagValue('ANONYMOUS_ACCESS', False, registry_server_executor.on(liveserver)):
        ... Features.ANONYMOUS_ACCESS is False in this context ...
  """

  def __init__(self, feature_flag, test_value, executor):
    self.feature_flag = feature_flag
    self.test_value = test_value
    self.executor = executor

    self.old_value = None

  def __enter__(self):
    result = self.executor.set_feature(self.feature_flag, self.test_value)
    self.old_value = result.json()['old_value']

  def __exit__(self, type, value, traceback):
    self.executor.set_feature(self.feature_flag, self.old_value)


class ApiCaller(object):
  def __init__(self, liveserver_session, registry_server_executor):
    self.liveserver_session = liveserver_session
    self.csrf_token = registry_server_executor.on_session(liveserver_session).generate_csrf()

  def conduct_auth(self, username, password):
    r = self.post('/api/v1/signin',
                  data=json.dumps(dict(username=username, password=password)),
                  headers={'Content-Type': 'application/json'})
    assert r.status_code == 200

  def _adjust_params(self, kwargs):
    if 'params' not in kwargs:
      kwargs['params'] = {}

    kwargs['params'].update({
      '_csrf_token': self.csrf_token,
    })
    return kwargs

  def get(self, url, **kwargs):
    kwargs = self._adjust_params(kwargs)
    return self.liveserver_session.get(url, **kwargs)

  def post(self, url, **kwargs):
    kwargs = self._adjust_params(kwargs)
    return self.liveserver_session.post(url, **kwargs)

  def change_repo_visibility(self, namespace, repository, visibility):
    self.post('/api/v1/repository/%s/%s/changevisibility' % (namespace, repository),
              data=json.dumps(dict(visibility=visibility)),
              headers={'Content-Type': 'application/json'})


@pytest.fixture(scope="function")
def api_caller(liveserver, registry_server_executor):
  return ApiCaller(liveserver.new_session(), registry_server_executor)