"""Module containing operation related views."""

# vim: set tw=80 ts=4 sw=4 sts=4:

import dateutil.parser

from flask_jwt_extended import jwt_required
from flask_restplus import Namespace, Resource, fields

from ..models import db, result_as_dicts
from ..models.accounts import Account
from ..models.operations import Operation


# pylint: disable=invalid-name
ns = Namespace('operation', description='Operation management')

# Operation with sold model.
operation_model = ns.model('Operation', {
    'id': fields.Integer(
        default=None,
        readonly=True,
        description='Id of the operation'),
    'operation_date': fields.Date(
        dt_format='iso8601',
        required=True,
        description='Date of the operation'),
    'label': fields.String(
        required=True,
        description='Label of the operation'),
    'value': fields.Float(
        required=True,
        description='Value of the operation'),
    'pointed': fields.Boolean(
        required=True,
        description='Pointed status of the operation'),
    'category': fields.String(
        required=False,
        default=None,
        description='Category of the operation'),
    'account_id': fields.Integer(
        required=True,
        readonly=True,
        description='Account id of the operation'),
    'scheduled_operation_id': fields.Integer(
        default=None,
        readonly=True,
        description='Scheduled operation ID of the operation'),
    'confirmed': fields.Boolean(
        description='Confirmed status of the operation'),
    'canceled': fields.Boolean(
        description='Canceled status of the operation (for a scheduled one)')
})

operation_with_balance_model = ns.clone(
    'OperationWithBalance', operation_model, {
        'balance': fields.Float(
            readonly=True,
            description='Cumulated balance'
        ),
    }
)

# Parser for a date range and an account id.
account_range_parser = ns.parser()
account_range_parser.add_argument(
    'begin',
    type=lambda a: dateutil.parser.parse(a) if a else None,
    required=False,
    default=None,
    location='args',
    help='Begin date of the time period'
)
account_range_parser.add_argument(
    'end',
    type=lambda a: dateutil.parser.parse(a) if a else None,
    required=False,
    default=None,
    location='args',
    help='End date of the time period'
)
account_range_parser.add_argument(
    'account_id',
    type=int,
    required=True,
    location='args',
    help='Id of the account'
)
# pylint: enable=invalid-name


# pylint: disable=no-self-use
@ns.route('/')
@ns.doc(
    security='apikey',
    responses={
        401: 'Unauthorized'
    })
class OperationListResource(Resource):
    """Resource to handle operation lists."""

    @ns.response(200, 'OK', [operation_with_balance_model])
    @ns.expect(account_range_parser)
    @ns.marshal_list_with(operation_with_balance_model)
    @jwt_required
    def get(self):
        """Get operations with cumulated balance for a specific account."""

        data = account_range_parser.parse_args()

        account_id = data['account_id']
        begin = data['begin']
        end = data['end']

        return list(result_as_dicts(
            Operation.query_with_balance(account_id, begin=begin, end=end)
        )), 200

    @ns.response(201, 'Operation created', operation_model)
    @ns.response(404, 'Account not found')
    @ns.response(406, 'Invalid operation data')
    @ns.marshal_with(operation_model)
    @jwt_required
    def post(self):
        """Create a new operation."""

        data = self.api.payload

        account_id = data['account_id']

        # FIXME Alexis Lahouze 2017-05-19 Check account_id presence.

        account = Account.query().get(account_id)

        if not account:
            ns.abort(404, 'Account with id %d not found.' % account_id)

        # A new operation MUST NOT have an id;
        if data.get('id') is not None:
            ns.abort(406, 'Id must not be provided on creation.')

        operation = Operation(**data)

        db.session.add(operation)  # pylint: disable=no-member

        return operation, 201


@ns.route('/<int:operation_id>')
@ns.doc(
    security='apikey',
    params={
        'operation_id': 'Id of the operation to manage'
    },
    responses={
        401: 'Unauthorized',
        404: 'Operation not found'
    })
class OperationResource(Resource):
    """Resource to handle operations."""

    @ns.response(200, 'OK', operation_model)
    @ns.marshal_with(operation_model)
    @jwt_required
    def get(self, operation_id):
        """Get operation."""

        # pylint: disable=no-member
        operation = db.session.query(Operation).get(operation_id)
        # pylint: enable=no-member

        if not operation:
            ns.abort(404, 'Operation with id %d not found.' % operation_id)

        return operation, 200

    @ns.expect(operation_model)
    @ns.response(200, 'OK', operation_model)
    @ns.response(406, 'Invalid operation data')
    @ns.marshal_with(operation_model)
    @jwt_required
    def post(self, operation_id):
        """Update an operation."""

        data = self.api.payload

        # Check ID consistency.
        if data.get('id', default=operation_id) != operation_id:
            ns.abort(406, 'Id must not be provided or changed on update.')

        # pylint: disable=no-member
        operation = db.session.query(Operation).get(operation_id)
        # pylint: enable=no-member

        if not operation:
            ns.abort(404, 'Operation with id %d not found.' % operation_id)

        # FIXME check account_id consistency.

        # SQLAlchemy objects ignore __dict__.update() with merge.
        for key, value in data.items():
            setattr(operation, key, value)

        db.session.merge(operation)  # pylint: disable=no-member

        return operation, 200

    @ns.response(204, 'Operation deleted', operation_model)
    @ns.marshal_with(operation_model)
    @jwt_required
    def delete(self, operation_id):
        """Delete an operation."""

        # pylint: disable=no-member
        operation = db.session.query(Operation).get(operation_id)
        # pylint: enable=no-member

        if not operation:
            ns.abort(404, 'Operation with id %d not found.' % operation_id)

        db.session.delete(operation)  # pylint: disable=no-member

        return None, 204