import logging
import json

from flask import Blueprint, request, make_response, jsonify
from flask.ext.restful import Resource, abort, Api, reqparse
from flask.ext.restful.utils.cors import crossdomain
from werkzeug.exceptions import HTTPException
from calendar import timegm
from email.utils import formatdate
from functools import partial, wraps
from jsonschema import validate, ValidationError

from data import model
from util.names import parse_namespace_repository
from auth.permissions import (ReadRepositoryPermission, ModifyRepositoryPermission,
                              AdministerRepositoryPermission, UserReadPermission,
                              UserAdminPermission)
from auth import scopes
from auth.auth_context import get_authenticated_user, get_validated_oauth_token
from auth.auth import process_oauth
from endpoints.csrf import csrf_protect


logger = logging.getLogger(__name__)
api_bp = Blueprint('api', __name__)
api = Api()
api.init_app(api_bp)
api.decorators = [csrf_protect,
                  process_oauth,
                  crossdomain(origin='*', headers=['Authorization', 'Content-Type'])]


class ApiException(Exception):
  def __init__(self, error_type, status_code, error_description, payload=None):
    Exception.__init__(self)
    self.error_description = error_description
    self.status_code = status_code
    self.payload = payload
    self.error_type = error_type

  def to_dict(self):
    rv = dict(self.payload or ())
    if self.error_description is not None:
      rv['error_description'] = self.error_description

    rv['error_type'] = self.error_type
    return rv


class InvalidRequest(ApiException):
  def __init__(self, error_description, payload=None):
    ApiException.__init__(self, 'invalid_request', 400, error_description, payload)


class InvalidToken(ApiException):
  def __init__(self, error_description, payload=None):
    ApiException.__init__(self, 'invalid_token', 401, error_description, payload)


class Unauthorized(ApiException):
  def __init__(self, payload=None):
    user = get_authenticated_user()
    if user is None or user.organization:
      ApiException.__init__(self, 'invalid_token', 401, "Requires authentication", payload)
    else:
      ApiException.__init__(self, 'insufficient_scope', 403, 'Unauthorized', payload)


class ExceedsLicenseException(ApiException):
  def __init__(self, payload=None):
    ApiException.__init__(self, None, 402, 'Payment Required', payload)


class NotFound(ApiException):
  def __init__(self, payload=None):
    ApiException.__init__(self, None, 404, 'Not Found', payload)


@api_bp.app_errorhandler(ApiException)
@crossdomain(origin='*', headers=['Authorization', 'Content-Type'])
def handle_api_error(error):
  response = jsonify(error.to_dict())
  response.status_code = error.status_code
  if error.error_type is not None:
    response.headers['WWW-Authenticate'] = ('Bearer error="%s" error_description="%s"' %
                                            (error.error_type, error.error_description))
  return response


def resource(*urls, **kwargs):
  def wrapper(api_resource):
    if not api_resource:
      return None

    api.add_resource(api_resource, *urls, **kwargs)
    return api_resource
  return wrapper


def show_if(value):
  def f(inner):
    if not value:
      return None

    return inner
  return f


def hide_if(value):
  def f(inner):
    if value:
      return None

    return inner
  return f


def truthy_bool(param):
  return param not in {False, 'false', 'False', '0', 'FALSE', '', 'null'}


def format_date(date):
  """ Output an RFC822 date format. """
  if date is None:
    return None
  return formatdate(timegm(date.utctimetuple()))


def add_method_metadata(name, value):
  def modifier(func):
    if func is None:
      return None

    if '__api_metadata' not in dir(func):
      func.__api_metadata = {}
    func.__api_metadata[name] = value
    return func
  return modifier


def method_metadata(func, name):
  if func is None:
    return None

  if '__api_metadata' in dir(func):
    return func.__api_metadata.get(name, None)
  return None



nickname = partial(add_method_metadata, 'nickname')
related_user_resource = partial(add_method_metadata, 'related_user_resource')
internal_only = add_method_metadata('internal', True)


def query_param(name, help_str, type=reqparse.text_type, default=None,
                choices=(), required=False):
  def add_param(func):
    if '__api_query_params' not in dir(func):
      func.__api_query_params = []
    func.__api_query_params.append({
      'name': name,
      'type': type,
      'help': help_str,
      'default': default,
      'choices': choices,
      'required': required,
    })
    return func
  return add_param


def parse_args(func):
  @wraps(func)
  def wrapper(self, *args, **kwargs):
    if '__api_query_params' not in dir(func):
      abort(500)

    parser = reqparse.RequestParser()
    for arg_spec in func.__api_query_params:
      parser.add_argument(**arg_spec)
    parsed_args = parser.parse_args()

    return func(self, parsed_args, *args, **kwargs)
  return wrapper


def parse_repository_name(func):
  @wraps(func)
  def wrapper(repository, *args, **kwargs):
    (namespace, repository) = parse_namespace_repository(repository)
    return func(namespace, repository, *args, **kwargs)
  return wrapper


class ApiResource(Resource):
  def options(self):
    return None, 200


class RepositoryParamResource(ApiResource):
  method_decorators = [parse_repository_name]


def require_repo_permission(permission_class, scope, allow_public=False):
  def wrapper(func):
    @add_method_metadata('oauth2_scope', scope)
    @wraps(func)
    def wrapped(self, namespace, repository, *args, **kwargs):
      logger.debug('Checking permission %s for repo: %s/%s', permission_class, namespace,
                   repository)
      permission = permission_class(namespace, repository)
      if (permission.can() or
          (allow_public and
           model.repository_is_public(namespace, repository))):
        return func(self, namespace, repository, *args, **kwargs)
      raise Unauthorized()
    return wrapped
  return wrapper


require_repo_read = require_repo_permission(ReadRepositoryPermission, scopes.READ_REPO, True)
require_repo_write = require_repo_permission(ModifyRepositoryPermission, scopes.WRITE_REPO)
require_repo_admin = require_repo_permission(AdministerRepositoryPermission, scopes.ADMIN_REPO)


def require_user_permission(permission_class, scope=None):
  def wrapper(func):
    @add_method_metadata('oauth2_scope', scope)
    @wraps(func)
    def wrapped(self, *args, **kwargs):
      user = get_authenticated_user()
      if not user:
        raise Unauthorized()

      logger.debug('Checking permission %s for user %s', permission_class, user.username)
      permission = permission_class(user.username)
      if permission.can():
        return func(self, *args, **kwargs)
      raise Unauthorized()
    return wrapped
  return wrapper


require_user_read = require_user_permission(UserReadPermission, scopes.READ_USER)
require_user_admin = require_user_permission(UserAdminPermission, None)


def require_scope(scope_object):
  def wrapper(func):
    @add_method_metadata('oauth2_scope', scope_object)
    @wraps(func)
    def wrapped(*args, **kwargs):
      return func(*args, **kwargs)
    return wrapped
  return wrapper


def validate_json_request(schema_name):
  def wrapper(func):
    @add_method_metadata('request_schema', schema_name)
    @wraps(func)
    def wrapped(self, *args, **kwargs):
      schema = self.schemas[schema_name]
      try:
        validate(request.get_json(), schema)
        return func(self, *args, **kwargs)
      except ValidationError as ex:
        raise InvalidRequest(ex.message)
    return wrapped
  return wrapper


def request_error(exception=None, **kwargs):
  data = kwargs.copy()
  message = 'Request error.'
  if exception:
    message = exception.message
  raise InvalidRequest(message, data)


def license_error(exception=None):
  raise ExceedsLicenseException()


def log_action(kind, user_or_orgname, metadata=None, repo=None):
  if not metadata:
    metadata = {}

  oauth_token = get_validated_oauth_token()
  if oauth_token:
    metadata['oauth_token_id'] = oauth_token.id
    metadata['oauth_token_application_id'] = oauth_token.application.client_id
    metadata['oauth_token_application'] = oauth_token.application.name

  performer = get_authenticated_user()
  model.log_action(kind, user_or_orgname, performer=performer, ip=request.remote_addr,
                   metadata=metadata, repository=repo)


import endpoints.api.billing
import endpoints.api.build
import endpoints.api.discovery
import endpoints.api.image
import endpoints.api.logs
import endpoints.api.organization
import endpoints.api.permission
import endpoints.api.prototype
import endpoints.api.repository
import endpoints.api.repositorynotification
import endpoints.api.repotoken
import endpoints.api.robot
import endpoints.api.search
import endpoints.api.superuser
import endpoints.api.tag
import endpoints.api.team
import endpoints.api.trigger
import endpoints.api.user