from __future__ import annotations

import sqlalchemy as sa
from geoalchemy2.elements import WKTElement
from uuid import UUID
from sqlalchemy.orm import Session

from backend.app.db.models import Track
from backend.app.repositories.base import BaseRepository
from backend.app.models import TrackCreate


class TrackRepository(BaseRepository[Track]):
    model = Track

    def __init__(self, session: Session) -> None:
        super().__init__(session)

    def list_all(self) -> list[Track]:
        statement = sa.select(self.model)
        return list(self.session.scalars(statement))

    @staticmethod
    def _ensure_uuid(value: UUID | str) -> UUID:
        if isinstance(value, UUID):
            return value
        return UUID(str(value))

    @staticmethod
    def _line_string(coordinates: list[tuple[float, float]]) -> WKTElement:
        if len(coordinates) < 2:
            raise ValueError("Track geometry requires at least two coordinate pairs")
        parts = [f"{lon} {lat}" for lat, lon in coordinates]
        return WKTElement(f"LINESTRING({', '.join(parts)})", srid=4326)

    def create(self, data: TrackCreate) -> Track:
        coordinates = list(data.coordinates)
        geometry = self._line_string(coordinates)
        track = Track(
            name=data.name,
            start_station_id=self._ensure_uuid(data.start_station_id),
            end_station_id=self._ensure_uuid(data.end_station_id),
            length_meters=data.length_meters,
            max_speed_kph=data.max_speed_kph,
            is_bidirectional=data.is_bidirectional,
            status=data.status,
            track_geometry=geometry,
        )
        self.session.add(track)
        return track