from __future__ import annotations

from datetime import datetime, timezone

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

from app.core.db.common import CommonBase


class AccountingInternalModel(CommonBase):
    __tablename__ = "accounting_internal_models"

    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)

    version_label: Mapped[str] = mapped_column(String(80), nullable=False, index=True)
    algorithm: Mapped[str] = mapped_column(String(80), nullable=False, default="multinomial_nb_v1")
    status: Mapped[str] = mapped_column(String(30), nullable=False, default="shadow", index=True)
    is_active: Mapped[bool] = mapped_column(Boolean, nullable=False, default=False, index=True)

    training_examples: Mapped[int] = mapped_column(Integer, nullable=False, default=0)
    validation_examples: Mapped[int] = mapped_column(Integer, nullable=False, default=0)
    class_count: Mapped[int] = mapped_column(Integer, nullable=False, default=0)
    vocabulary_size: Mapped[int] = mapped_column(Integer, nullable=False, default=0)

    validation_accuracy: Mapped[float] = mapped_column(Float, nullable=False, default=0)
    validation_macro_recall: Mapped[float] = mapped_column(Float, nullable=False, default=0)
    validation_top2_accuracy: Mapped[float] = mapped_column(Float, nullable=False, default=0)

    model_json: Mapped[str] = mapped_column(Text, nullable=False)
    metrics_json: Mapped[str | None] = mapped_column(Text, nullable=True)
    training_summary_json: Mapped[str | None] = mapped_column(Text, nullable=True)

    trained_by_user_id: Mapped[int | None] = mapped_column(
        ForeignKey("users.id", ondelete="SET NULL"), nullable=True
    )
    trained_at_utc: Mapped[datetime] = mapped_column(
        DateTime(timezone=True), nullable=False, default=lambda: datetime.now(timezone.utc), index=True
    )


class AccountingInternalPrediction(CommonBase):
    __tablename__ = "accounting_internal_predictions"

    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)
    model_id: Mapped[int] = mapped_column(
        ForeignKey("accounting_internal_models.id", ondelete="CASCADE"), nullable=False, index=True
    )

    source_type: Mapped[str] = mapped_column(String(30), nullable=False, index=True)
    source_record_id: Mapped[int] = mapped_column(Integer, nullable=False, index=True)
    source_fingerprint: Mapped[str] = mapped_column(String(80), nullable=False, default="", index=True)

    predicted_nature_id: Mapped[int | None] = mapped_column(
        ForeignKey("accounting_natures.id", ondelete="SET NULL"), nullable=True, index=True
    )
    predicted_probability: Mapped[float] = mapped_column(Float, nullable=False, default=0)
    top2_json: Mapped[str | None] = mapped_column(Text, nullable=True)
    explanation_json: Mapped[str | None] = mapped_column(Text, nullable=True)

    shadow_mode: Mapped[bool] = mapped_column(Boolean, nullable=False, default=True, index=True)
    applied_to_source: Mapped[bool] = mapped_column(Boolean, nullable=False, default=False, index=True)

    final_nature_id: Mapped[int | None] = mapped_column(
        ForeignKey("accounting_natures.id", ondelete="SET NULL"), nullable=True, index=True
    )
    prediction_correct: Mapped[bool | None] = mapped_column(Boolean, nullable=True, index=True)
    reviewed_by_user_id: Mapped[int | None] = mapped_column(
        ForeignKey("users.id", ondelete="SET NULL"), nullable=True
    )
    reviewed_at_utc: Mapped[datetime | None] = mapped_column(DateTime(timezone=True), nullable=True)

    created_at_utc: Mapped[datetime] = mapped_column(
        DateTime(timezone=True), nullable=False, default=lambda: datetime.now(timezone.utc), index=True
    )