"""Module for requests validation."""

from functools import wraps

from jsonschema import validate
from jsonschema import ValidationError
from oto import response
from oto.adaptors.flask import flaskify as oto_flaskify

from assets.constants import field_const
from assets.constants import error as error_const
from assets.validation.schema import header


def validate_headers(request, required=True):
    """A decorator to call when validating HTTP request headers.

    Args:
        request (werkzeug.local.LocalProxy): request object from the handler.

    Returns:
        callable: the wrapped function.
    """
    def wrap(function):
        @wraps(function)
        def wrapped_f(*args, **kwargs):
            if required or (not required and field_const.ORCHARD_USER_ID
                            in request.headers):
                try:
                    validate(dict(request.headers), header.user_headers_schema)
                except ValidationError as error:
                    return oto_flaskify(
                        response.create_error_response(
                            code=error_const.ERROR_CODE_HEADER_VALIDATION,
                            message=str(error)))
            return function(*args, **kwargs)

        return wrapped_f
    return wrap


def validate_body(request, schema):
    """A decorator to call when validating HTTP request body.

    Args:
        request (werkzeug.local.LocalProxy): Request object from the handler.
        schema (Draft4Validator): The JSON Draft4 Schema to validate against.

    Returns:
        callable: the wrapped function.
    """
    def wrap(function):
        @wraps(function)
        def wrapped_f(*args, **kwargs):
            try:
                validate(request.get_json(), schema)
            except ValidationError as error:
                return oto_flaskify(
                    response.create_error_response(
                        code=error_const.ERROR_CODE_BODY_VALIDATION,
                        message=str(error)))
            return function(*args, **kwargs)
        return wrapped_f
    return wrap


def validate_query(request, schema):
    """A decorator to call when validating query arguments.

    Args:
        request (werkzeug.local.LocalProxy): Request object from the handler.
        schema (Draft4Validator): The JSON Draft4 Schema to validate against.

    Returns:
        callable: the wrapped function.
    """
    def wrap(function):
        @wraps(function)
        def wrapped_f(*args, **kwargs):
            try:
                source_query = dict(request.args)
                query_dict = {k: (v[0] if len(v) == 1 else v) for k, v in
                              source_query.items()}
                validate(query_dict, schema)
            except ValidationError as error:
                return oto_flaskify(
                    response.create_error_response(
                        code=error_const.ERROR_CODE_QUERY_VALIDATION,
                        message=str(error)))
            return function(*args, **kwargs)
        return wrapped_f
    return wrap