# Copyright (C) 2022 The Software Heritage developers
# See the AUTHORS file at the top-level directory of this distribution
# License: GNU General Public License version 3, or any later version
# See top-level LICENSE file for more information

from datetime import datetime

from ariadne import ScalarType

from swh.graphql.errors import InvalidInputError
from swh.graphql.utils import utils
from swh.model import hashutil
from swh.model.exceptions import ValidationError
from swh.model.model import TimestampWithTimezone
from swh.model.swhids import CoreSWHID

datetime_scalar = ScalarType("DateTime")
swhid_scalar = ScalarType("SWHID")
id_scalar = ScalarType("ID")
content_hash_scalar = ScalarType("ContentHash")


@id_scalar.serializer
def serialize_id(value):
    if type(value) is bytes:
        return value.hex()
    return value


@datetime_scalar.serializer
def serialize_datetime(value):
    # FIXME, handle error and return None
    if type(value) == TimestampWithTimezone:
        value = value.to_datetime()
    if type(value) == datetime:
        return utils.get_formatted_date(value)
    return None


@swhid_scalar.value_parser
def validate_swhid(value):
    try:
        swhid = CoreSWHID.from_string(value)
    except ValidationError as e:
        raise InvalidInputError("Invalid SWHID", e)
    return swhid


@swhid_scalar.serializer
def serialize_swhid(value):
    return str(value)


@content_hash_scalar.value_parser
def validate_content_hash(value):
    try:
        hash_type, hash_string = value.split(":")
        hash_value = hashutil.hash_to_bytes(hash_string)
    except ValueError as e:
        raise InvalidInputError("Invalid content checksum", e)
    if hash_type not in hashutil.ALGORITHMS:
        raise InvalidInputError("Invalid hash algorithm")
    return hash_type, hash_value