import uuid
from datetime import datetime
from decimal import Decimal

from sqlalchemy import (
    BigInteger,
    Boolean,
    CheckConstraint,
    DateTime,
    ForeignKey,
    Identity,
    Index,
    Numeric,
    String,
    Text,
    UniqueConstraint,
    func,
    text,
)
from sqlalchemy.orm import Mapped, mapped_column

from app.db import Base


class WebSession(Base):
    __tablename__ = "web_sessions"

    id: Mapped[uuid.UUID] = mapped_column(primary_key=True, default=uuid.uuid4)
    created_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), server_default=func.now())


class Category(Base):
    __tablename__ = "categories"

    id: Mapped[int] = mapped_column(BigInteger, Identity(always=True), primary_key=True)
    name: Mapped[str] = mapped_column(String(80), unique=True)


class Product(Base):
    __tablename__ = "products"
    __table_args__ = (
        CheckConstraint("price >= 0", name="products_price_nonnegative"),
        Index(
            "products_active_category_price_idx",
            "category_id",
            "price",
            "id",
            postgresql_where=text("is_active"),
        ),
    )

    id: Mapped[int] = mapped_column(BigInteger, Identity(always=True), primary_key=True)
    category_id: Mapped[int] = mapped_column(ForeignKey("categories.id"), nullable=False)
    title: Mapped[str] = mapped_column(String(255), nullable=False)
    description: Mapped[str] = mapped_column(Text, nullable=False, default="")
    price: Mapped[Decimal] = mapped_column(Numeric(12, 2), nullable=False)
    is_active: Mapped[bool] = mapped_column(Boolean, nullable=False, default=True, server_default=text("true"))
    image_key: Mapped[str | None] = mapped_column(String(255))
    created_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), server_default=func.now())


class CartItem(Base):
    __tablename__ = "cart_items"
    __table_args__ = (
        UniqueConstraint("owner_key", "product_id", name="uq_cart_owner_product"),
        CheckConstraint("qty > 0 AND qty <= 99", name="cart_qty_range"),
        Index("ix_cart_owner", "owner_key"),
    )

    id: Mapped[int] = mapped_column(BigInteger, Identity(always=True), primary_key=True)
    owner_key: Mapped[str] = mapped_column(String(96), nullable=False)
    product_id: Mapped[int] = mapped_column(ForeignKey("products.id"), nullable=False)
    qty: Mapped[int] = mapped_column(nullable=False)


class Order(Base):
    __tablename__ = "orders"
    __table_args__ = (Index("ix_orders_owner", "owner_key"),)

    id: Mapped[int] = mapped_column(BigInteger, Identity(always=True), primary_key=True)
    owner_key: Mapped[str] = mapped_column(String(96), nullable=False)
    customer_name: Mapped[str] = mapped_column(String(120), nullable=False)
    customer_phone: Mapped[str] = mapped_column(String(32), nullable=False)
    status: Mapped[str] = mapped_column(String(20), nullable=False, default="created", server_default="created")
    total: Mapped[Decimal] = mapped_column(Numeric(12, 2), nullable=False)
    created_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), server_default=func.now())


class OrderItem(Base):
    __tablename__ = "order_items"

    id: Mapped[int] = mapped_column(BigInteger, Identity(always=True), primary_key=True)
    order_id: Mapped[int] = mapped_column(ForeignKey("orders.id", ondelete="CASCADE"), nullable=False)
    product_id: Mapped[int] = mapped_column(ForeignKey("products.id"), nullable=False)
    title: Mapped[str] = mapped_column(String(255), nullable=False)
    price: Mapped[Decimal] = mapped_column(Numeric(12, 2), nullable=False)
    qty: Mapped[int] = mapped_column(nullable=False)


class BotDialog(Base):
    __tablename__ = "bot_dialogs"

    telegram_user_id: Mapped[int] = mapped_column(BigInteger, primary_key=True)
    step: Mapped[str] = mapped_column(String(16), nullable=False)
    name: Mapped[str | None] = mapped_column(String(120))
    updated_at: Mapped[datetime] = mapped_column(
        DateTime(timezone=True), server_default=func.now(), onupdate=func.now()
    )


class TelegramUpdate(Base):
    __tablename__ = "telegram_updates"

    update_id: Mapped[int] = mapped_column(BigInteger, primary_key=True)
    processed_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), server_default=func.now())