# models/database_models.py
from sqlalchemy import Column, Integer, String, DateTime, ForeignKey, Index, UniqueConstraint, Boolean
from sqlalchemy.ext.declarative import declarative_base
from sqlalchemy.orm import relationship
from datetime import datetime

Base = declarative_base()


class User(Base):
    __tablename__ = "users"

    id = Column(Integer, primary_key=True, index=True)
    email = Column(String, unique=True, index=True, nullable=False)
    username = Column(String, unique=True, index=True, nullable=False)
    hashed_password = Column(String, nullable=False)
    role = Column(String, nullable=False, default="user")  # 'admin' or 'user'
    is_active = Column(Boolean, default=True, nullable=False)
    last_login = Column(DateTime, nullable=True)
    created_at = Column(DateTime, default=datetime.utcnow, nullable=False)
    updated_at = Column(DateTime, default=datetime.utcnow, onupdate=datetime.utcnow, nullable=False)

    def __repr__(self):
        return f"<User(username='{self.username}', email='{self.email}', role='{self.role}')>"


class Product(Base):
    __tablename__ = "products"

    id = Column(Integer, primary_key=True, index=True)
    product_id = Column(String, unique=True, index=True, nullable=False)
    title = Column(String, nullable=False)
    description = Column(String)
    link = Column(String)
    image_link = Column(String)
    availability = Column(String, index=True)  # Index for filtering
    price = Column(String)
    brand = Column(String, index=True)  # Index for filtering
    gtin = Column(String, index=True)  # Index for stock lookups
    mpn = Column(String)
    condition = Column(String)
    adult = Column(String)
    multipack = Column(Integer)
    is_bundle = Column(String)
    age_group = Column(String)
    color = Column(String)
    gender = Column(String)
    material = Column(String)
    pattern = Column(String)
    size = Column(String)
    size_type = Column(String)
    size_system = Column(String)
    item_group_id = Column(String)
    google_product_category = Column(String, index=True)  # Index for filtering
    product_type = Column(String)
    custom_label_0 = Column(String)
    custom_label_1 = Column(String)
    custom_label_2 = Column(String)
    custom_label_3 = Column(String)
    custom_label_4 = Column(String)
    additional_image_link = Column(String)
    sale_price = Column(String)
    unit_pricing_measure = Column(String)
    unit_pricing_base_measure = Column(String)
    identifier_exists = Column(String)
    shipping = Column(String)
    currency = Column(String)
    created_at = Column(DateTime, default=datetime.utcnow, nullable=False)
    updated_at = Column(DateTime, default=datetime.utcnow, onupdate=datetime.utcnow, nullable=False)

    # Relationship to stock (one-to-many via GTIN)
    stock_entries = relationship("Stock", foreign_keys="Stock.gtin", primaryjoin="Product.gtin == Stock.gtin",
                                 viewonly=True)

    def __repr__(self):
        return f"<Product(product_id='{self.product_id}', title='{self.title}')>"


class Stock(Base):
    __tablename__ = "stock"

    id = Column(Integer, primary_key=True, index=True)
    gtin = Column(String, index=True, nullable=False)  # Foreign key relationship would be ideal
    location = Column(String, nullable=False, index=True)
    quantity = Column(Integer, nullable=False, default=0)
    created_at = Column(DateTime, default=datetime.utcnow, nullable=False)
    updated_at = Column(DateTime, default=datetime.utcnow, onupdate=datetime.utcnow, nullable=False)

    # Composite unique constraint to prevent duplicate GTIN-location combinations
    __table_args__ = (
        UniqueConstraint('gtin', 'location', name='uq_stock_gtin_location'),
        Index('idx_stock_gtin_location', 'gtin', 'location'),  # Composite index for efficient queries
    )

    def __repr__(self):
        return f"<Stock(gtin='{self.gtin}', location='{self.location}', quantity={self.quantity})>"


class ImportJob(Base):
    __tablename__ = "import_jobs"

    id = Column(Integer, primary_key=True, index=True)
    status = Column(String, nullable=False,
                    default="pending")  # pending, processing, completed, failed, completed_with_errors
    source_url = Column(String, nullable=False)
    user_id = Column(Integer, ForeignKey('users.id'))  # Foreign key to users table
    imported_count = Column(Integer, default=0)
    updated_count = Column(Integer, default=0)
    error_count = Column(Integer, default=0)
    total_processed = Column(Integer, default=0)
    error_message = Column(String)
    created_at = Column(DateTime, default=datetime.utcnow, nullable=False)
    started_at = Column(DateTime)
    completed_at = Column(DateTime)

    # Relationship to user
    user = relationship("User", foreign_keys=[user_id])

    def __repr__(self):
        return f"<ImportJob(id={self.id}, status='{self.status}', imported={self.imported_count})>"