import uuid

from sqlalchemy import (
    Column,
    DateTime,
    Enum,
    ForeignKey,
    Integer,
    Unicode,
    UniqueConstraint,
    text,
)
from sqlalchemy.dialects.postgresql import UUID
from sqlalchemy.orm import relationship

from .kot import Kot
from .meta import Base
from .voucher_type import VoucherType


class Voucher(Base):
    __tablename__ = "vouchers"
    __table_args__ = (UniqueConstraint("bill_id", "voucher_type"),)

    id = Column(
        "id", UUID(as_uuid=True), primary_key=True, server_default=text("gen_random_uuid()"), default=uuid.uuid4
    )
    date = Column("date", DateTime, nullable=False, index=True)
    pax = Column("pax", Integer, nullable=False)
    bill_id = Column("bill_id", Integer)
    kot_id = Column("kot_id", Integer, nullable=False, unique=True)
    creation_date = Column("creation_date", DateTime(), nullable=False)
    last_edit_date = Column("last_edit_date", DateTime(), nullable=False)
    food_table_id = Column(
        "food_table_id",
        UUID(as_uuid=True),
        ForeignKey("food_tables.id"),
        nullable=False,
    )
    customer_id = Column("customer_id", UUID(as_uuid=True), ForeignKey("customers.id"))
    narration = Column("narration", Unicode(1000), nullable=True)
    reason = Column("reason", Unicode(255))
    voucher_type = Column("voucher_type", Enum(VoucherType), nullable=False)
    user_id = Column("user_id", UUID(as_uuid=True), ForeignKey("users.id"), nullable=False)

    user = relationship("User", backref="vouchers")
    food_table = relationship("FoodTable", backref="vouchers")
    customer = relationship("Customer", backref="vouchers")

    kots = relationship(
        "Kot",
        backref="voucher",
        cascade="delete, delete-orphan",
        cascade_backrefs=False,
        order_by=Kot.date,
    )
    settlements = relationship(
        "Settlement",
        backref="voucher",
        cascade="delete, delete-orphan",
        cascade_backrefs=False,
    )
    reprints = relationship(
        "Reprint",
        backref="voucher",
        cascade="delete, delete-orphan",
        cascade_backrefs=False,
    )

    def __init__(
        self,
        date,
        pax,
        bill_id,
        kot_id,
        food_table_id,
        customer_id,
        voucher_type,
        user_id,
    ):
        self.date = date
        self.pax = pax
        self.creation_date = date
        self.last_edit_date = date
        self.bill_id = bill_id
        self.kot_id = kot_id
        self.food_table_id = food_table_id
        self.customer_id = customer_id
        self.narration = None
        self.voucher_type = voucher_type
        self.user_id = user_id

    @property
    def full_bill_id(self):
        if self.voucher_type == VoucherType.KOT:
            return "K-" + str(self.kot_id)
        if self.voucher_type == VoucherType.NO_CHARGE:
            return "NC-" + str(self.bill_id)
        if self.voucher_type == VoucherType.STAFF:
            return "ST-" + str(self.bill_id)
        if self.voucher_type == VoucherType.REGULAR_BILL:
            return str(self.bill_id // 10000) + "-" + str(self.bill_id % 10000)
        if self.voucher_type == VoucherType.VOID:
            return "K-" + str(self.kot_id)
        else:
            raise Exception

    @property
    def amount(self):
        return round(sum(i.amount for k in self.kots for i in k.inventories), 2)