from datetime import datetime
from typing import List, Optional
from sqlmodel import Field, SQLModel, Relationship

# --- User & Auth ---
class User(SQLModel, table=True):
    id: Optional[int] = Field(default=None, primary_key=True)
    username: str = Field(index=True, unique=True)
    hashed_password: str
    is_active: bool = Field(default=True)
    is_admin: bool = Field(default=False)

# --- Inventory & Materials ---
class Material(SQLModel, table=True):
    id: Optional[int] = Field(default=None, primary_key=True)
    name: str = Field(index=True)
    description: Optional[str] = None
    unit: str  # e.g., "meters", "units", "grams"
    stock_quantity: float = Field(default=0.0)
    reorder_level: float = Field(default=0.0)
    cost_per_unit: float = Field(default=0.0)

# --- Products ---
class Product(SQLModel, table=True):
    id: Optional[int] = Field(default=None, primary_key=True)
    name: str = Field(index=True)
    sku: str = Field(index=True, unique=True)
    description: Optional[str] = None
    base_price: float = Field(default=0.0)
    estimated_time_hours: float = Field(default=0.0)
    
    # Relationships
    orders: List["OrderProductLink"] = Relationship(back_populates="product")
    materials: List["ProductMaterialLink"] = Relationship(back_populates="product")

class ProductMaterialLink(SQLModel, table=True):
    product_id: Optional[int] = Field(default=None, foreign_key="product.id", primary_key=True)
    material_id: Optional[int] = Field(default=None, foreign_key="material.id", primary_key=True)
    quantity_required: float
    
    product: Product = Relationship(back_populates="materials")
    material: Material = Relationship()

# --- CRM ---
class Client(SQLModel, table=True):
    id: Optional[int] = Field(default=None, primary_key=True)
    full_name: str = Field(index=True)
    email: Optional[str] = None
    phone: Optional[str] = None
    address: Optional[str] = None
    
    # Measurements (as a JSON or separate fields, keeping it simple for now)
    measurements: Optional[str] = None # Or use a JSON type if supported better
    
    orders: List["Order"] = Relationship(back_populates="client")

# --- Orders & Production ---
class OrderStatus(str):
    QUOTATION = "Quotation"
    PENDING = "Pending"
    IN_PRODUCTION = "In Production"
    SHIPPED = "Shipped"
    DELIVERED = "Delivered"
    CANCELLED = "Cancelled"

class Order(SQLModel, table=True):
    id: Optional[int] = Field(default=None, primary_key=True)
    client_id: int = Field(foreign_key="client.id")
    order_date: datetime = Field(default_factory=datetime.utcnow)
    status: str = Field(default=OrderStatus.QUOTATION)
    total_amount: float = Field(default=0.0)
    notes: Optional[str] = None
    
    client: Client = Relationship(back_populates="orders")
    products: List["OrderProductLink"] = Relationship(back_populates="order")

class OrderProductLink(SQLModel, table=True):
    order_id: Optional[int] = Field(default=None, foreign_key="order.id", primary_key=True)
    product_id: Optional[int] = Field(default=None, foreign_key="product.id", primary_key=True)
    quantity: int = Field(default=1)
    customizations: Optional[str] = None
    
    order: Order = Relationship(back_populates="products")
    product: Product = Relationship(back_populates="orders")

class ProductionStep(SQLModel, table=True):
    id: Optional[int] = Field(default=None, primary_key=True)
    order_id: int = Field(foreign_key="order.id")
    step_name: str # e.g., "Corte", "Confección", "Terminado"
    status: str = Field(default="Pending") # Pending, In Progress, Completed
    assigned_to: Optional[int] = Field(default=None, foreign_key="user.id")
    started_at: Optional[datetime] = None
    completed_at: Optional[datetime] = None