"""
Product Split Model.

Model for getting information about product split.

"""

from sqlalchemy import BigInteger, Column, Float, Integer, exc as sqlexeption

from contracts import response
from contracts.connectors import mysql
from contracts.constants import contracts_constants
from contracts.models import contract_history


class ProductSplit(mysql.BaseModel):
    """ProductSplit class."""

    __tablename__ = 'product_split'

    product_split_id = Column(Integer, primary_key=True)  # noqa B001, B003
    vendor_id = Column(Integer)
    product_id = Column(BigInteger)
    product_split_rate = Column(Float)

    def to_dict(self):
        """Get a dict representation."""
        return {'upc': self.product_id, 'product_split': self.product_split_rate}


def get_product_split(vendor_id, page_offset=None, page_limit=None):
    """Get a product split for provided vendor.

    Args:
        vendor_id (int): Vendor Id.
    Returns:
        response.Response: list of upcs and product_splits

    """
    sort = ProductSplit.product_split_id
    with mysql.db_session() as session:
        query = (
            session.query(ProductSplit)
            .filter(ProductSplit.vendor_id == vendor_id)
            .order_by(sort.desc())
        )

        paginated_query = query.offset(page_offset).limit(page_limit)
        result = [r.to_dict() for r in paginated_query.all()]

        session.expunge_all()

        result_data = {
            'items': result,
            'pagination': {
                'type': 'standard',
                'offset': page_offset,
                'limit': page_limit,
                'total_records': query.count(),
            },
        }
        return response.Response(result_data)


def set_product_split(data, vendor_id):
    """Set a product split for provided UPC.

    Args:
        data (list): a list of dictionaries
        vendor_id (int): Vendor_id
    Returns:
        response.Response: status

    """
    with mysql.db_session() as session:
        for item in data:
            product_split = ProductSplit(
                product_id=item['upc'],
                product_split_rate=item['product_split_rate'],
                vendor_id=vendor_id,
            )
            vendor_history = contract_history.set_product_change_history(
                contracts_constants.SET_PRODUCT_SPLIT_MESSAGE,
                item['upc'],
                item['vend_contract_id'],
                item['oa_user_id'],
                item['product_split_rate'],
            )
            try:
                session.add(product_split)
                session.add(vendor_history)
                session.flush()
            except sqlexeption.IntegrityError:
                session.rollback()
                return response.create_error_response('Conflict', 'Duplicate UPC', 409)
        session.commit()
    return response.create_status_ok_response()


def update_product_split(data):
    """Update a product split for provided UPC.

    Args:
        data (list): a list of dictionaries
    Returns:
        response.Response: status

    """
    with mysql.db_session() as session:
        for item in data:
            row = (
                session.query(ProductSplit)
                .filter(ProductSplit.product_id == item['upc'])
                .first()
            )
            if not row:
                return response.create_not_found_response(
                    item['upc'].join(['UPC: ', ' not found'])
                )
            row.product_split_rate = item['product_split_rate']
            vendor_history = contract_history.set_product_change_history(
                contracts_constants.UPDATE_PRODUCT_SPLIT_MESSAGE,
                item['upc'],
                item['vend_contract_id'],
                item['oa_user_id'],
                item['product_split_rate'],
            )
            session.add(vendor_history)
            session.flush()
        session.commit()
    return response.create_status_ok_response()


def delete_product_split(upc, data):
    """Delete a product split for provided UPC.

    Args:
        upc (int): UPC.
    Returns:
        response.Response: status

    """
    with mysql.db_session() as session:
        row = session.query(ProductSplit).filter(ProductSplit.product_id == upc).first()
        if not row:
            return response.create_not_found_response(upc.join(['UPC: ', ' not found']))
        session.delete(row)
        vendor_history = contract_history.set_product_change_history(
            contracts_constants.DELETE_PRODUCT_SPLIT_MESSAGE,
            upc,
            data['vend_contract_id'],
            data['oa_user_id'],
        )
        session.add(vendor_history)
        session.commit()
    return response.create_status_ok_response()