"""Portable column types: the same models run on Postgres (prod/compose) and SQLite (tests)."""

from datetime import UTC, datetime
from typing import Any

from sqlalchemy import JSON, DateTime, Dialect
from sqlalchemy.dialects.postgresql import JSONB
from sqlalchemy.types import TypeDecorator

# JSONB on Postgres (indexable, compact), plain JSON elsewhere. Lists are stored as JSON instead of ARRAY
# so the schema stays portable to SQLite.
JSONType = JSON().with_variant(JSONB(), "postgresql")


class TZDateTime(TypeDecorator[datetime]):
    """Timezone-aware timestamp, stored in UTC.

    Rejects naive datetimes: every business timestamp must come from `app.core.clock` (ADR-005), which
    returns aware values. SQLite drops tzinfo on storage, so values read back are re-tagged as UTC.
    """

    impl = DateTime(timezone=True)
    cache_ok = True

    def process_bind_param(self, value: datetime | None, dialect: Dialect) -> datetime | None:
        if value is None:
            return None
        if value.tzinfo is None:
            raise ValueError("naive datetime: take time from app.core.clock (ADR-005)")
        return value.astimezone(UTC)

    def process_result_value(self, value: Any, dialect: Dialect) -> datetime | None:
        if value is None:
            return None
        if value.tzinfo is None:
            return value.replace(tzinfo=UTC)
        return value