from connexion import NoContent

from crc import session
from crc.api.common import ApiError, ApiErrorSchema
from crc.models.study import StudyModelSchema, StudyModel
from crc.models.workflow import WorkflowModel, WorkflowModelSchema, WorkflowSpecModel
from crc.workflow_processor import WorkflowProcessor


def all_studies():
    # todo: Limit returned studies to a user
    schema = StudyModelSchema(many=True)
    return schema.dump(session.query(StudyModel).all())


def add_study(body):
    study = StudyModelSchema().load(body, session=session)
    session.add(study)
    session.commit()
    return StudyModelSchema().dump(study)


def update_study(study_id, body):
    if study_id is None:
        error = ApiError('unknown_study', 'Please provide a valid Study ID.')
        return ApiErrorSchema.dump(error), 404

    study = session.query(StudyModel).filter_by(id=study_id).first()

    if study is None:
        error = ApiError('unknown_study', 'The study "' + study_id + '" is not recognized.')
        return ApiErrorSchema.dump(error), 404

    study = StudyModelSchema().load(body, session=session)
    session.add(study)
    session.commit()
    return StudyModelSchema().dump(study)


def get_study(study_id):
    study = session.query(StudyModel).filter_by(id=study_id).first()
    schema = StudyModelSchema()
    if study is None:
        return NoContent, 404
    return schema.dump(study)


def post_update_study_from_protocol_builder(study_id):
    # todo: Actually get data from an external service here
    return NoContent, 304


def get_study_workflows(study_id):
    workflows = session.query(WorkflowModel).filter_by(study_id=study_id).all()
    schema = WorkflowModelSchema(many=True)
    return schema.dump(workflows)


def add_workflow_to_study(study_id, body):
    workflow_spec_model = session.query(WorkflowSpecModel).filter_by(id=body["id"]).first()
    if workflow_spec_model is None:
        error = ApiError('unknown_spec', 'The specification "' + body['id'] + '" is not recognized.')
        return ApiErrorSchema.dump(error), 404

    processor = WorkflowProcessor.create(workflow_spec_model.id)
    workflow = WorkflowModel(bpmn_workflow_json=processor.serialize(),
                             status=processor.get_status(),
                             study_id=study_id,
                             workflow_spec_id=workflow_spec_model.id)
    session.add(workflow)
    session.commit()
    return WorkflowModelSchema().dump(workflow)