import json

from app.core.db import get_connection
from app.schemas.common import ListResponse
from app.schemas.observation import ObservationSummary


class ObservationRepository:
    def save(self, observation: ObservationSummary) -> None:
        payload_json = json.dumps(observation.model_dump())
        with get_connection() as connection:
            connection.execute(
                """
                INSERT OR REPLACE INTO observations (id, payload_json)
                VALUES (?, ?)
                """,
                (observation.id, payload_json),
            )
            connection.commit()

    def get(self, observation_id: str) -> ObservationSummary | None:
        with get_connection() as connection:
            row = connection.execute(
                """
                SELECT payload_json
                FROM observations
                WHERE id = ?
                """,
                (observation_id,),
            ).fetchone()
        if row is None:
            return None
        return ObservationSummary.model_validate_json(row["payload_json"])

    def list(self) -> ListResponse[ObservationSummary]:
        with get_connection() as connection:
            rows = connection.execute(
                """
                SELECT payload_json
                FROM observations
                ORDER BY created_at DESC
                """
            ).fetchall()
        items = [
            ObservationSummary.model_validate_json(row["payload_json"]) for row in rows
        ]
        return ListResponse(items=items)