"""Phase 5.5 — Accounts Receivable & Payable domain models."""
from __future__ import annotations

import uuid
from datetime import date
from decimal import Decimal

from sqlalchemy import (
    Boolean,
    Date,
    ForeignKey,
    Index,
    Integer,
    Numeric,
    String,
    Text,
    UniqueConstraint,
)
from sqlalchemy.orm import Mapped, mapped_column, relationship

from app.core.database import Base
from app.models.base import TenantMixin, TimestampMixin, UUIDPrimaryKeyMixin
from app.models.types import GUID, InvoiceStatus, SettlementStatus


class CustomerAccount(Base, UUIDPrimaryKeyMixin, TenantMixin, TimestampMixin):
    __tablename__ = "customer_accounts"

    code: Mapped[str] = mapped_column(String(50), nullable=False)
    name: Mapped[str] = mapped_column(String(255), nullable=False)
    account_id: Mapped[uuid.UUID | None] = mapped_column(GUID(), nullable=True)
    credit_limit: Mapped[Decimal | None] = mapped_column(Numeric(18, 4), nullable=True)
    currency_id: Mapped[uuid.UUID | None] = mapped_column(GUID(), nullable=True)
    outstanding_balance: Mapped[Decimal] = mapped_column(
        Numeric(18, 4), default=Decimal("0"), nullable=False
    )
    is_active: Mapped[bool] = mapped_column(Boolean, default=True, nullable=False)

    invoices: Mapped[list["ReceivableInvoice"]] = relationship(back_populates="customer")

    __table_args__ = (
        UniqueConstraint("tenant_id", "code", name="uq_customer_tenant_code"),
    )


class SupplierAccount(Base, UUIDPrimaryKeyMixin, TenantMixin, TimestampMixin):
    __tablename__ = "supplier_accounts"

    code: Mapped[str] = mapped_column(String(50), nullable=False)
    name: Mapped[str] = mapped_column(String(255), nullable=False)
    account_id: Mapped[uuid.UUID | None] = mapped_column(GUID(), nullable=True)
    currency_id: Mapped[uuid.UUID | None] = mapped_column(GUID(), nullable=True)
    outstanding_balance: Mapped[Decimal] = mapped_column(
        Numeric(18, 4), default=Decimal("0"), nullable=False
    )
    is_active: Mapped[bool] = mapped_column(Boolean, default=True, nullable=False)

    invoices: Mapped[list["PayableInvoice"]] = relationship(back_populates="supplier")

    __table_args__ = (
        UniqueConstraint("tenant_id", "code", name="uq_supplier_tenant_code"),
    )


class ReceivableInvoice(Base, UUIDPrimaryKeyMixin, TenantMixin, TimestampMixin):
    __tablename__ = "receivable_invoices"

    customer_id: Mapped[uuid.UUID] = mapped_column(
        GUID(), ForeignKey("customer_accounts.id", ondelete="RESTRICT"), nullable=False
    )
    invoice_number: Mapped[str] = mapped_column(String(50), nullable=False)
    invoice_date: Mapped[date] = mapped_column(Date, nullable=False)
    due_date: Mapped[date | None] = mapped_column(Date, nullable=True)
    total_amount: Mapped[Decimal] = mapped_column(Numeric(18, 4), nullable=False)
    paid_amount: Mapped[Decimal] = mapped_column(
        Numeric(18, 4), default=Decimal("0"), nullable=False
    )
    remaining_amount: Mapped[Decimal] = mapped_column(Numeric(18, 4), nullable=False)
    status: Mapped[InvoiceStatus] = mapped_column(nullable=False)
    voucher_id: Mapped[uuid.UUID | None] = mapped_column(GUID(), nullable=True)
    currency_id: Mapped[uuid.UUID | None] = mapped_column(GUID(), nullable=True)

    customer: Mapped["CustomerAccount"] = relationship(back_populates="invoices")

    __table_args__ = (
        UniqueConstraint("tenant_id", "invoice_number", name="uq_receivable_inv_tenant_number"),
        Index("ix_receivable_inv_customer", "tenant_id", "customer_id"),
    )


class PayableInvoice(Base, UUIDPrimaryKeyMixin, TenantMixin, TimestampMixin):
    __tablename__ = "payable_invoices"

    supplier_id: Mapped[uuid.UUID] = mapped_column(
        GUID(), ForeignKey("supplier_accounts.id", ondelete="RESTRICT"), nullable=False
    )
    invoice_number: Mapped[str] = mapped_column(String(50), nullable=False)
    invoice_date: Mapped[date] = mapped_column(Date, nullable=False)
    due_date: Mapped[date | None] = mapped_column(Date, nullable=True)
    total_amount: Mapped[Decimal] = mapped_column(Numeric(18, 4), nullable=False)
    paid_amount: Mapped[Decimal] = mapped_column(
        Numeric(18, 4), default=Decimal("0"), nullable=False
    )
    remaining_amount: Mapped[Decimal] = mapped_column(Numeric(18, 4), nullable=False)
    status: Mapped[InvoiceStatus] = mapped_column(nullable=False)
    voucher_id: Mapped[uuid.UUID | None] = mapped_column(GUID(), nullable=True)
    currency_id: Mapped[uuid.UUID | None] = mapped_column(GUID(), nullable=True)

    supplier: Mapped["SupplierAccount"] = relationship(back_populates="invoices")

    __table_args__ = (
        UniqueConstraint("tenant_id", "invoice_number", name="uq_payable_inv_tenant_number"),
        Index("ix_payable_inv_supplier", "tenant_id", "supplier_id"),
    )


class Settlement(Base, UUIDPrimaryKeyMixin, TenantMixin, TimestampMixin):
    __tablename__ = "settlements"

    settlement_number: Mapped[str] = mapped_column(String(50), nullable=False)
    settlement_date: Mapped[date] = mapped_column(Date, nullable=False)
    settlement_type: Mapped[str] = mapped_column(String(20), nullable=False)
    party_type: Mapped[str] = mapped_column(String(20), nullable=False)
    party_id: Mapped[uuid.UUID] = mapped_column(GUID(), nullable=False)
    total_amount: Mapped[Decimal] = mapped_column(Numeric(18, 4), nullable=False)
    status: Mapped[SettlementStatus] = mapped_column(nullable=False)
    voucher_id: Mapped[uuid.UUID | None] = mapped_column(GUID(), nullable=True)

    allocations: Mapped[list["SettlementAllocation"]] = relationship(
        back_populates="settlement", cascade="all, delete-orphan"
    )

    __table_args__ = (
        UniqueConstraint("tenant_id", "settlement_number", name="uq_settlement_tenant_number"),
    )


class SettlementAllocation(Base, UUIDPrimaryKeyMixin, TenantMixin, TimestampMixin):
    __tablename__ = "settlement_allocations"

    settlement_id: Mapped[uuid.UUID] = mapped_column(
        GUID(), ForeignKey("settlements.id", ondelete="CASCADE"), nullable=False
    )
    invoice_type: Mapped[str] = mapped_column(String(20), nullable=False)
    invoice_id: Mapped[uuid.UUID] = mapped_column(GUID(), nullable=False)
    allocated_amount: Mapped[Decimal] = mapped_column(Numeric(18, 4), nullable=False)

    settlement: Mapped["Settlement"] = relationship(back_populates="allocations")


class CreditNote(Base, UUIDPrimaryKeyMixin, TenantMixin, TimestampMixin):
    __tablename__ = "credit_notes"

    note_number: Mapped[str] = mapped_column(String(50), nullable=False)
    note_date: Mapped[date] = mapped_column(Date, nullable=False)
    party_type: Mapped[str] = mapped_column(String(20), nullable=False)
    party_id: Mapped[uuid.UUID] = mapped_column(GUID(), nullable=False)
    amount: Mapped[Decimal] = mapped_column(Numeric(18, 4), nullable=False)
    reason: Mapped[str | None] = mapped_column(Text, nullable=True)
    voucher_id: Mapped[uuid.UUID | None] = mapped_column(GUID(), nullable=True)

    __table_args__ = (
        UniqueConstraint("tenant_id", "note_number", name="uq_credit_note_tenant_number"),
    )


class DebitNote(Base, UUIDPrimaryKeyMixin, TenantMixin, TimestampMixin):
    __tablename__ = "debit_notes"

    note_number: Mapped[str] = mapped_column(String(50), nullable=False)
    note_date: Mapped[date] = mapped_column(Date, nullable=False)
    party_type: Mapped[str] = mapped_column(String(20), nullable=False)
    party_id: Mapped[uuid.UUID] = mapped_column(GUID(), nullable=False)
    amount: Mapped[Decimal] = mapped_column(Numeric(18, 4), nullable=False)
    reason: Mapped[str | None] = mapped_column(Text, nullable=True)
    voucher_id: Mapped[uuid.UUID | None] = mapped_column(GUID(), nullable=True)

    __table_args__ = (
        UniqueConstraint("tenant_id", "note_number", name="uq_debit_note_tenant_number"),
    )


class AdvancePayment(Base, UUIDPrimaryKeyMixin, TenantMixin, TimestampMixin):
    __tablename__ = "advance_payments"

    supplier_id: Mapped[uuid.UUID] = mapped_column(GUID(), nullable=False)
    amount: Mapped[Decimal] = mapped_column(Numeric(18, 4), nullable=False)
    remaining_amount: Mapped[Decimal] = mapped_column(Numeric(18, 4), nullable=False)
    payment_date: Mapped[date] = mapped_column(Date, nullable=False)
    voucher_id: Mapped[uuid.UUID | None] = mapped_column(GUID(), nullable=True)


class AdvanceReceipt(Base, UUIDPrimaryKeyMixin, TenantMixin, TimestampMixin):
    __tablename__ = "advance_receipts"

    customer_id: Mapped[uuid.UUID] = mapped_column(GUID(), nullable=False)
    amount: Mapped[Decimal] = mapped_column(Numeric(18, 4), nullable=False)
    remaining_amount: Mapped[Decimal] = mapped_column(Numeric(18, 4), nullable=False)
    receipt_date: Mapped[date] = mapped_column(Date, nullable=False)
    voucher_id: Mapped[uuid.UUID | None] = mapped_column(GUID(), nullable=True)


class CustomerStatement(Base, UUIDPrimaryKeyMixin, TenantMixin, TimestampMixin):
    __tablename__ = "customer_statements"

    customer_id: Mapped[uuid.UUID] = mapped_column(GUID(), nullable=False)
    statement_date: Mapped[date] = mapped_column(Date, nullable=False)
    opening_balance: Mapped[Decimal] = mapped_column(Numeric(18, 4), nullable=False)
    closing_balance: Mapped[Decimal] = mapped_column(Numeric(18, 4), nullable=False)
    statement_data: Mapped[str | None] = mapped_column(Text, nullable=True)


class SupplierStatement(Base, UUIDPrimaryKeyMixin, TenantMixin, TimestampMixin):
    __tablename__ = "supplier_statements"

    supplier_id: Mapped[uuid.UUID] = mapped_column(GUID(), nullable=False)
    statement_date: Mapped[date] = mapped_column(Date, nullable=False)
    opening_balance: Mapped[Decimal] = mapped_column(Numeric(18, 4), nullable=False)
    closing_balance: Mapped[Decimal] = mapped_column(Numeric(18, 4), nullable=False)
    statement_data: Mapped[str | None] = mapped_column(Text, nullable=True)


class AgingSnapshot(Base, UUIDPrimaryKeyMixin, TenantMixin, TimestampMixin):
    __tablename__ = "aging_snapshots"

    party_type: Mapped[str] = mapped_column(String(20), nullable=False)
    party_id: Mapped[uuid.UUID] = mapped_column(GUID(), nullable=False)
    snapshot_date: Mapped[date] = mapped_column(Date, nullable=False)
    current_amount: Mapped[Decimal] = mapped_column(Numeric(18, 4), nullable=False)
    days_1_30: Mapped[Decimal] = mapped_column(Numeric(18, 4), nullable=False)
    days_31_60: Mapped[Decimal] = mapped_column(Numeric(18, 4), nullable=False)
    days_61_90: Mapped[Decimal] = mapped_column(Numeric(18, 4), nullable=False)
    days_90_plus: Mapped[Decimal] = mapped_column(Numeric(18, 4), nullable=False)
    total_outstanding: Mapped[Decimal] = mapped_column(Numeric(18, 4), nullable=False)

    __table_args__ = (
        Index("ix_aging_snapshot_party", "tenant_id", "party_type", "party_id"),
    )