map_writer.py

"""Write the active POI map configuration safely."""

from __future__ import annotations

import json
from pathlib import Path
from threading import Lock
from typing import Any


REPO_ROOT = Path(__file__).resolve().parent
MAP_ROOT = REPO_ROOT / "threejs-poi-map-demo"
MAP_IMAGES_ROOT = MAP_ROOT / "images"
MAP_CONFIG_PATH = MAP_ROOT / "config.js"
GROUND_MAP_PATH = MAP_IMAGES_ROOT / "ground-map.png"
_config_lock = Lock()
_ground_map_lock = Lock()


def write_active_map(
    *,
    latitude: float,
    longitude: float,
    radius_m: int,
    mood: str,
    mood_text: str,
    recommendation: str,
    pois: list[dict[str, Any]],
    ground_map_url: str | None = None,
) -> None:
    """Atomically replace the active, location-scoped map data.

    A map represents one user location at a time. Replacing the JSON payload
    prevents stale POIs from earlier locations from leaking outside its radius.
    """

    MAP_IMAGES_ROOT.mkdir(parents=True, exist_ok=True)
    payload = {
        "origin": {"lat": latitude, "lon": longitude},
        "radius_m": radius_m,
        "mood": mood,
        # The raw text the user typed/spoke, as opposed to `mood` (the short resolved
        # label like "hungry" used for prompt-building). The mood textarea restores
        # from this on page load -- without it, the full-page reload after every real
        # search re-parsed index.html's hardcoded default textarea content and silently
        # overwrote whatever the user had actually typed.
        "mood_text": mood_text,
        "recommendation": recommendation,
        "pois": pois,
        "ground_map_url": ground_map_url,
    }
    source = "window.POI_MAP_CONFIG = " + json.dumps(payload, indent=2, ensure_ascii=False) + ";\n"
    temporary_path = MAP_CONFIG_PATH.with_suffix(".tmp")
    with _config_lock:
        temporary_path.write_text(source, encoding="utf-8")
        temporary_path.replace(MAP_CONFIG_PATH)


def write_ground_map_image(image_bytes: bytes) -> None:
    """Atomically replace the ground-plane satellite/street overlay image."""

    MAP_IMAGES_ROOT.mkdir(parents=True, exist_ok=True)
    temporary_path = GROUND_MAP_PATH.with_suffix(".tmp")
    with _ground_map_lock:
        temporary_path.write_bytes(image_bytes)
        temporary_path.replace(GROUND_MAP_PATH)


def image_path_for(poi_id: str) -> Path:
    safe_id = "".join(character.lower() if character.isalnum() else "-" for character in poi_id)
    safe_id = "-".join(part for part in safe_id.split("-") if part)[:72] or "poi"
    return MAP_IMAGES_ROOT / f"generated-{safe_id}.png"


def map_image_url(path: Path) -> str:
    return path.resolve().relative_to(MAP_ROOT.resolve()).as_posix()