"""ImportSettings — single-row table holding the importer's tunable knobs.

Enforced as a single row via a CHECK (id = 1) constraint. The application
always SELECTs id=1 and never inserts/deletes after the initial migration.
"""

from sqlalchemy import Boolean, CheckConstraint, Float, Integer, Text
from sqlalchemy.orm import Mapped, mapped_column

from .base import Base


class ImportSettings(Base):
    __tablename__ = "import_settings"
    # Bare constraint name — Base.metadata's naming convention applies the
    # ck_<table>_<name> prefix, producing the final ck_import_settings_singleton.
    __table_args__ = (CheckConstraint("id = 1", name="singleton"),)

    id: Mapped[int] = mapped_column(Integer, primary_key=True)
    import_scan_path: Mapped[str] = mapped_column(Text, nullable=False, default="/import")

    min_width: Mapped[int] = mapped_column(Integer, nullable=False, default=0)
    min_height: Mapped[int] = mapped_column(Integer, nullable=False, default=0)

    skip_transparent: Mapped[bool] = mapped_column(Boolean, nullable=False, default=False)
    transparency_threshold: Mapped[float] = mapped_column(Float, nullable=False, default=0.9)

    skip_single_color: Mapped[bool] = mapped_column(Boolean, nullable=False, default=False)
    single_color_threshold: Mapped[float] = mapped_column(Float, nullable=False, default=0.95)
    single_color_tolerance: Mapped[int] = mapped_column(Integer, nullable=False, default=30)

    phash_threshold: Mapped[int] = mapped_column(Integer, nullable=False, default=10)

    # FC-3c downloader knobs
    download_rate_limit_seconds: Mapped[float] = mapped_column(
        Float, nullable=False, default=3.0
    )
    download_validate_files: Mapped[bool] = mapped_column(
        Boolean, nullable=False, default=True
    )

    # FC-3d scheduling knobs
    download_schedule_default_seconds: Mapped[int] = mapped_column(
        Integer, nullable=False, default=28800
    )
    download_event_retention_days: Mapped[int] = mapped_column(
        Integer, nullable=False, default=90
    )
    download_failure_warning_threshold: Mapped[int] = mapped_column(
        Integer, nullable=False, default=5
    )

    # FC-3h backup knobs.
    backup_db_nightly_enabled: Mapped[bool] = mapped_column(
        Boolean, nullable=False, default=False,
    )
    backup_db_nightly_hour_utc: Mapped[int] = mapped_column(
        Integer, nullable=False, default=3,
    )
    backup_db_keep_last_n: Mapped[int] = mapped_column(
        Integer, nullable=False, default=14,
    )
    backup_images_keep_last_n: Mapped[int] = mapped_column(
        Integer, nullable=False, default=3,
    )