MAX_RESULT_BUNDLE_BYTES = 64 * 1024 * 1024
REMOTE_ASSIGNMENT_BASELINE_BYTES = 2 * 1024 * 1024
REMOTE_ASSIGNMENT_MAX_ACTIVE = 50


def validate_remote_assignment_capacity(config):
    values = {}
    fields = (
        'result_bundle_max_event_bytes',
        'remote_assignment_reserve_bytes',
        'remote_assignment_max_active',
        'result_bundle_max_total_bytes',
        'projection_backlog_max_bytes',
        'projection_backlog_headroom_bytes',
        'keycheck_queue_max_items',
        'keycheck_queue_max_bytes',
        'keycheck_candidates_per_event',
        'keycheck_candidate_bytes_per_event',
    )
    for name in fields:
        value = config.get(name)
        if type(value) is not int or value < 0:
            raise ValueError(name)
        values[name] = value

    hard_limit = values['result_bundle_max_event_bytes']
    reserve = values['remote_assignment_reserve_bytes']
    active = values['remote_assignment_max_active']
    if not REMOTE_ASSIGNMENT_BASELINE_BYTES <= reserve <= hard_limit:
        raise ValueError('remote_assignment_reserve_bytes')
    if not REMOTE_ASSIGNMENT_BASELINE_BYTES <= hard_limit <= MAX_RESULT_BUNDLE_BYTES:
        raise ValueError('result_bundle_max_event_bytes')
    if not 1 <= active <= REMOTE_ASSIGNMENT_MAX_ACTIVE:
        raise ValueError('remote_assignment_max_active')

    required_bytes = active * reserve
    if values['result_bundle_max_total_bytes'] < required_bytes:
        raise ValueError('result_bundle_max_total_bytes')
    projection_admission_bytes = (
        values['projection_backlog_max_bytes']
        - values['projection_backlog_headroom_bytes']
    )
    if projection_admission_bytes < required_bytes:
        raise ValueError('projection_backlog_max_bytes')
    if (
        values['keycheck_queue_max_items']
        < active * values['keycheck_candidates_per_event']
    ):
        raise ValueError('keycheck_queue_max_items')
    if (
        values['keycheck_queue_max_bytes']
        < active * values['keycheck_candidate_bytes_per_event']
    ):
        raise ValueError('keycheck_queue_max_bytes')
    return values