from __future__ import annotations

from datetime import datetime, timezone

from sqlalchemy import DateTime, Float, ForeignKey, Integer, String, Text, UniqueConstraint
from sqlalchemy.orm import Mapped, mapped_column

from app.core.db.common import CommonBase


def _utcnow():
    return datetime.now(timezone.utc)


class AccountingOpeningBalanceRun(CommonBase):
    __tablename__ = "accounting_opening_balance_runs"

    id: Mapped[int] = mapped_column(Integer, primary_key=True, autoincrement=True)
    tenant_id: Mapped[int] = mapped_column(ForeignKey("tenants.id", ondelete="CASCADE"), nullable=False, index=True)
    client_id: Mapped[int] = mapped_column(ForeignKey("clients.id", ondelete="CASCADE"), nullable=False, index=True)

    previous_company_name: Mapped[str] = mapped_column(String(255), nullable=False)
    previous_company_guid: Mapped[str] = mapped_column(String(120), nullable=False, default="")
    current_company_name: Mapped[str] = mapped_column(String(255), nullable=False)
    current_company_guid: Mapped[str] = mapped_column(String(120), nullable=False, default="")

    status: Mapped[str] = mapped_column(String(30), nullable=False, default="completed", index=True)
    ledger_count: Mapped[int] = mapped_column(Integer, nullable=False, default=0)
    stock_item_count: Mapped[int] = mapped_column(Integer, nullable=False, default=0)
    summary_json: Mapped[str] = mapped_column(Text, nullable=False, default="{}")
    created_by_user_id: Mapped[int | None] = mapped_column(ForeignKey("users.id", ondelete="SET NULL"), nullable=True)
    created_at_utc: Mapped[datetime] = mapped_column(DateTime(timezone=True), nullable=False, default=_utcnow, index=True)


class AccountingOpeningLedgerItem(CommonBase):
    __tablename__ = "accounting_opening_ledger_items"

    id: Mapped[int] = mapped_column(Integer, primary_key=True, autoincrement=True)
    run_id: Mapped[int] = mapped_column(ForeignKey("accounting_opening_balance_runs.id", ondelete="CASCADE"), nullable=False, index=True)

    previous_name: Mapped[str] = mapped_column(String(255), nullable=False, default="", index=True)
    previous_guid: Mapped[str] = mapped_column(String(120), nullable=False, default="")
    previous_group: Mapped[str] = mapped_column(String(255), nullable=False, default="")
    previous_closing_balance: Mapped[float] = mapped_column(Float, nullable=False, default=0)

    current_name: Mapped[str] = mapped_column(String(255), nullable=False, default="", index=True)
    current_guid: Mapped[str] = mapped_column(String(120), nullable=False, default="")
    current_group: Mapped[str] = mapped_column(String(255), nullable=False, default="")
    current_opening_balance: Mapped[float] = mapped_column(Float, nullable=False, default=0)

    difference: Mapped[float] = mapped_column(Float, nullable=False, default=0)
    match_status: Mapped[str] = mapped_column(String(40), nullable=False, index=True)
    match_method: Mapped[str] = mapped_column(String(50), nullable=False, default="")
    confidence: Mapped[int] = mapped_column(Integer, nullable=False, default=0)

    correction_status: Mapped[str] = mapped_column(String(40), nullable=False, default="not_requested", index=True)
    correction_note: Mapped[str] = mapped_column(Text, nullable=False, default="")
    verified_opening_balance: Mapped[float | None] = mapped_column(Float, nullable=True)
    corrected_by_user_id: Mapped[int | None] = mapped_column(ForeignKey("users.id", ondelete="SET NULL"), nullable=True)
    corrected_at_utc: Mapped[datetime | None] = mapped_column(DateTime(timezone=True), nullable=True)


class AccountingOpeningStockItem(CommonBase):
    __tablename__ = "accounting_opening_stock_items"

    id: Mapped[int] = mapped_column(Integer, primary_key=True, autoincrement=True)
    run_id: Mapped[int] = mapped_column(ForeignKey("accounting_opening_balance_runs.id", ondelete="CASCADE"), nullable=False, index=True)

    previous_name: Mapped[str] = mapped_column(String(255), nullable=False, default="", index=True)
    previous_guid: Mapped[str] = mapped_column(String(120), nullable=False, default="")
    previous_group: Mapped[str] = mapped_column(String(255), nullable=False, default="")
    previous_hsn: Mapped[str] = mapped_column(String(40), nullable=False, default="")
    previous_unit: Mapped[str] = mapped_column(String(80), nullable=False, default="")
    previous_closing_qty: Mapped[float] = mapped_column(Float, nullable=False, default=0)
    previous_closing_value: Mapped[float] = mapped_column(Float, nullable=False, default=0)
    previous_closing_rate: Mapped[str] = mapped_column(String(100), nullable=False, default="")

    current_name: Mapped[str] = mapped_column(String(255), nullable=False, default="", index=True)
    current_guid: Mapped[str] = mapped_column(String(120), nullable=False, default="")
    current_group: Mapped[str] = mapped_column(String(255), nullable=False, default="")
    current_hsn: Mapped[str] = mapped_column(String(40), nullable=False, default="")
    current_unit: Mapped[str] = mapped_column(String(80), nullable=False, default="")
    current_opening_qty: Mapped[float] = mapped_column(Float, nullable=False, default=0)
    current_opening_value: Mapped[float] = mapped_column(Float, nullable=False, default=0)

    quantity_difference: Mapped[float] = mapped_column(Float, nullable=False, default=0)
    value_difference: Mapped[float] = mapped_column(Float, nullable=False, default=0)
    match_status: Mapped[str] = mapped_column(String(50), nullable=False, index=True)
    match_method: Mapped[str] = mapped_column(String(50), nullable=False, default="")
    confidence: Mapped[int] = mapped_column(Integer, nullable=False, default=0)

    correction_status: Mapped[str] = mapped_column(String(40), nullable=False, default="not_requested", index=True)
    correction_note: Mapped[str] = mapped_column(Text, nullable=False, default="")
    verified_opening_qty: Mapped[float | None] = mapped_column(Float, nullable=True)
    verified_opening_value: Mapped[float | None] = mapped_column(Float, nullable=True)
    corrected_by_user_id: Mapped[int | None] = mapped_column(ForeignKey("users.id", ondelete="SET NULL"), nullable=True)
    corrected_at_utc: Mapped[datetime | None] = mapped_column(DateTime(timezone=True), nullable=True)


class AccountingOpeningMasterMapping(CommonBase):
    __tablename__ = "accounting_opening_master_mappings"
    __table_args__ = (
        UniqueConstraint(
            "tenant_id",
            "client_id",
            "master_type",
            "previous_company_guid",
            "previous_name_norm",
            "current_company_guid",
            name="uq_accounting_opening_master_mapping",
        ),
    )

    id: Mapped[int] = mapped_column(Integer, primary_key=True, autoincrement=True)
    tenant_id: Mapped[int] = mapped_column(ForeignKey("tenants.id", ondelete="CASCADE"), nullable=False, index=True)
    client_id: Mapped[int] = mapped_column(ForeignKey("clients.id", ondelete="CASCADE"), nullable=False, index=True)
    master_type: Mapped[str] = mapped_column(String(20), nullable=False, index=True)

    previous_company_guid: Mapped[str] = mapped_column(String(120), nullable=False, default="")
    previous_name: Mapped[str] = mapped_column(String(255), nullable=False)
    previous_name_norm: Mapped[str] = mapped_column(String(255), nullable=False, index=True)

    current_company_guid: Mapped[str] = mapped_column(String(120), nullable=False, default="")
    current_name: Mapped[str] = mapped_column(String(255), nullable=False)

    note: Mapped[str] = mapped_column(Text, nullable=False, default="")
    created_by_user_id: Mapped[int | None] = mapped_column(ForeignKey("users.id", ondelete="SET NULL"), nullable=True)
    created_at_utc: Mapped[datetime] = mapped_column(DateTime(timezone=True), nullable=False, default=_utcnow)