"""
Normalized Database Schema for SCAF (Fixed Assets) and SCAII (Parts Inventory)
SQLAlchemy v2 - Annex 24 Compliance
"""

from typing import Optional, TYPE_CHECKING, List
from sqlalchemy import Boolean, String, Integer, ForeignKey
from sqlalchemy.orm import Mapped, mapped_column, relationship
from api.v1.common.base_models import TenantScopedMixin, TimestampMixin
from core.database import Base

if TYPE_CHECKING:
    from .line_items.models import LineItem

# ============================================================================
# CORE ENTITIES
# ============================================================================


class Item(Base, TenantScopedMixin, TimestampMixin):
    """
    Unified item header table for all import/export operations
    Consolidates headers from both SCAF and SCAII systems
    """
    __tablename__ = "items"
    __table_args__ = {
        "schema": "a76",
    }

    id: Mapped[int] = mapped_column(primary_key=True, autoincrement=True)
    invoice_id: Mapped[int] = mapped_column(ForeignKey("a76.invoice_header.id"))  # CONSECUTIVO        

    # Item references
    reference_number: Mapped[Optional[str]] = mapped_column(
        String(20))  # NUMREFERENCIA
    order: Mapped[Optional[str]] = mapped_column(
        String(50))  # ORDENCOMPRA / ORDENVENTA
    guide_number: Mapped[Optional[str]] = mapped_column(
        String(50))  # NUMEROGUIA/NUMERODEGUIA

    # Dates
    depreciation_date: Mapped[Optional[int]] = mapped_column(
        Integer)  # FECHADEPRECIACION

    # Administrative fields
    rectification: Mapped[Optional[bool]] = mapped_column(
        Boolean)  # RECTIFICACION
    warehouse: Mapped[Optional[str]] = mapped_column(String(30))  # BODEGA
    location: Mapped[Optional[str]] = mapped_column(
        String(200))  # LOCALIZACION

    # Relationships (one-to-many)
    lines: Mapped[List["LineItem"]] = relationship(
        "LineItem", back_populates="item", cascade="all, delete-orphan")
    
    invoice: Mapped["InvoiceHeader"] = relationship("InvoiceHeader")

# ============================================================================
# SUPPORTING TABLES
# ============================================================================


class PackingList(Base, TenantScopedMixin, TimestampMixin):
    """
    Packing list items
    From: SPartidasPackingList
    """
    __tablename__ = "packing_lists"
    __table_args__ = {
        "schema": "a76",
    }

    id: Mapped[int] = mapped_column(primary_key=True, autoincrement=True)
    item_line_id: Mapped[int] = mapped_column(Integer)  # LINEA
    packing_list_number: Mapped[Optional[str]] = mapped_column(
        String(100))  # NUMPACKINGLIST


class CTMReceipt(Base, TenantScopedMixin, TimestampMixin):
    """
    CTM Receipt lines (temporary manufacturing)
    From: SPartidasReciboCTM
    """
    __tablename__ = "ctm_receipts"
    __table_args__ = {
        "schema": "a76",
    }

    id: Mapped[int] = mapped_column(primary_key=True, autoincrement=True)
    receipt_line: Mapped[int] = mapped_column(
        ForeignKey("a76.item_lines.id"))  # LINEARECIBO

    option: Mapped[Optional[str]] = mapped_column(String(3))  # OPCION
    exit_invoice: Mapped[Optional[str]] = mapped_column(
        String(19))  # FACTURASALIDA


class SubassemblyEntry(Base, TenantScopedMixin, TimestampMixin):
    """
    Subassembly/Submanufacturing Entry lines
    From: SPartidasEntradaSM
    """
    __tablename__ = "subassembly_entries"
    __table_args__ = {
        "schema": "a76",
    }

    id: Mapped[int] = mapped_column(primary_key=True, autoincrement=True)
    remission_line: Mapped[int] = mapped_column(Integer)  # LINEAREMISION
    exit_invoice: Mapped[Optional[str]] = mapped_column(
String(15))  # FACTURASALIDA
    exit_line: Mapped[Optional[int]] = mapped_column(Integer)  # LINEASALIDA

# ============================================================================
# INDEXES AND CONSTRAINTS
# ============================================================================


"""
Recommended indexes for optimal query performance:

CREATE INDEX idx_items_consecutive ON items(consecutive);
CREATE INDEX idx_items_invoice ON items(invoice_number);
CREATE INDEX idx_items_type_system ON items(item_type, system_origin);
CREATE INDEX idx_items_dates ON items(invoice_date, depreciation_date);

CREATE INDEX idx_lines_item ON item_lines(item_id);
CREATE INDEX idx_lines_part ON item_lines(part_number);
CREATE INDEX idx_lines_class ON item_lines(class_code);
CREATE INDEX idx_lines_invoice_refs ON item_lines(import_invoice, export_invoice);
CREATE INDEX idx_lines_fractions ON item_lines(import_fraction, export_fraction);

CREATE INDEX idx_packing_consecutive ON packing_lists(consecutive);
CREATE INDEX idx_packing_part ON packing_lists(part_number);

CREATE INDEX idx_repair_invoice ON repair_parts(import_invoice, import_line);
CREATE INDEX idx_ctm_ship_consec ON ctm_shipments(consecutive);
CREATE INDEX idx_ctm_rcpt_consec ON ctm_receipts(consecutive);
CREATE INDEX idx_sub_entry_consec ON subassembly_entries(consecutive);
CREATE INDEX idx_sub_exit_consec ON subassembly_exits(consecutive);
CREATE INDEX idx_imposition_consec ON imposition_parts(consecutive);
"""


# ============================================================================
# MIGRATION NOTES
# ============================================================================

"""
MIGRATION STRATEGY FROM ORIGINAL TABLES TO NORMALIZED SCHEMA:

1. DOCUMENT MAPPING:
   - QEqeMaq (Equipment Import Temp) → items (type='EQUIPMENT_IMPORT_TEMP', system='SCAF')
   - QEqeMaqRep (Equipment Repair Export) → items (type='EQUIPMENT_REPAIR_EXPORT', system='SCAF')
   - QEqiDef (Equipment Import Definitive) → items (type='EQUIPMENT_IMPORT_DEF', system='SCAF')
   - QEqiMaq (Equipment Machinery) → items (type='EQUIPMENT_MACHINERY', system='SCAF')
   - QEqiMaqRep (Equipment Machinery Repair) → items (type='EQUIPMENT_REPAIR_IMPORT', system='SCAF')
   - SPartidasCM (Common Commerce) → items (type='COMMON_COMMERCE', system='SCAII')
   - SPartidasExpo (Export) → items (type='EXPORT', system='SCAII')
   - SPartidasImpo (Import) → items (type='IMPORT', system='SCAII')

2. LINE MAPPING:
   All line items from Q* and SPartidas* tables map to item_lines with appropriate
   field mapping based on the original column names (preserved as comments).

3. FIELD CONSOLIDATION RULES:
   - Costs: Unified under unit_cost_* with currency suffix (usd/mxn/mc)
   - Values: Unified under value_* with currency suffix
   - Quantities: Unified under quantity_* with specific purpose suffixes
   - Descriptions: Consolidated into description_spanish/english/extra
   - Fractions: All fraction fields preserved with clear naming
   
4. DATA INTEGRITY:
   - Original CONSECUTIVO + LINE number preserved for traceability
   - Foreign key relationships established via item_id
   - All original fields retained to prevent data loss
   
5. SPECIAL TABLES:
   - PackingList, RepairPart, CTM*, Subassembly*, ImpositionPart remain separate
     as they serve specific purposes and don't fit the main item/line pattern

6. BENEFITS:
   - Eliminates redundancy across 13 original tables
   - Unified query interface for all operations
   - Maintains full audit trail with original field names
   - Enables cross-system reporting (SCAF + SCAII)
   - Simplifies maintenance with single schema
   
7. QUERYING EXAMPLES:
   ```python
   # Get all imports (both systems)
   session.query(Item).filter(
       Item.item_type.in_(['IMPORT', 'EQUIPMENT_IMPORT_TEMP', 'EQUIPMENT_IMPORT_DEF'])
   )
   
   # Get all lines for a specific part across all items
   session.query(LineItem).filter(
       LineItem.part_number == 'ABC123'
   )
   
   # Get SCAF equipment with depreciation
   session.query(Item).join(LineItem).filter(
       Item.system_origin == 'SCAF',
       LineItem.value_depreciated_usd.isnot(None)
   )
   ```
"""