import { SEARCH_ICON } from "/js/icons.js";
import { escapeHtml } from "/js/gpx.js";

const NOMINATIM_API = "https://nominatim.openstreetmap.org/search";
// "lat, lng" / "lat lng" decimal degrees — the same plain-text shape the
// topbar's own coordinate readout copies to the clipboard (map.js). Tried
// before hitting the geocoder, so pasting a coordinate pair jumps straight
// there with no network round-trip.
const COORD_PATTERN = /^\s*(-?\d+(?:\.\d+)?)\s*[, ]\s*(-?\d+(?:\.\d+)?)\s*$/;

// A place-name/coordinate search box, matching NPS's own Park Tiles viewer.
// Online only, like this app's other non-basemap online features (Radar,
// the Wikipedia layer) — no offline geocoding index to fall back to.
// Nominatim: OpenStreetMap's own geocoder, free, no API key, matching the
// online basemap's own OSM-derived style already used here.
export class SearchControl {
  constructor() {
    this._results = [];
  }

  onAdd(map) {
    this._map = map;
    this._container = document.createElement("div");
    this._container.className = "maplibregl-ctrl maplibregl-ctrl-group search-ctrl";
    this._container.innerHTML = `
      <button type="button" class="search-ctrl__button" title="Search" aria-label="Search">${SEARCH_ICON}</button>
      <div class="search-panel" hidden>
        <form class="search-panel__form">
          <input type="text" class="search-panel__input" placeholder="Search, or lat, lng">
        </form>
        <ul class="search-panel__results"></ul>
      </div>
    `;
    this._button = this._container.querySelector(".search-ctrl__button");
    this._panel = this._container.querySelector(".search-panel");
    this._input = this._container.querySelector(".search-panel__input");
    this._resultsEl = this._container.querySelector(".search-panel__results");

    this._button.addEventListener("click", () => this._toggle());
    this._container.querySelector(".search-panel__form").addEventListener("submit", (event) => {
      event.preventDefault();
      this._search();
    });

    return this._container;
  }

  onRemove() {
    this._container.remove();
  }

  getDefaultPosition() {
    return "top-left";
  }

  _toggle() {
    const opening = this._panel.hidden;
    this._panel.hidden = !opening;
    this._button.classList.toggle("active", opening);
    if (opening) this._input.focus();
  }

  async _search() {
    const query = this._input.value.trim();
    if (!query) return;

    const coords = query.match(COORD_PATTERN);
    if (coords) {
      this._resultsEl.innerHTML = "";
      this._jumpTo(Number(coords[1]), Number(coords[2]));
      return;
    }

    this._resultsEl.innerHTML = `<li class="search-panel__status">Searching…</li>`;
    let places;
    try {
      const url = new URL(NOMINATIM_API);
      url.searchParams.set("q", query);
      url.searchParams.set("format", "jsonv2");
      url.searchParams.set("limit", "5");
      places = await (await fetch(url)).json();
    } catch {
      this._resultsEl.innerHTML = `<li class="search-panel__status">Search unavailable — check your connection.</li>`;
      return;
    }
    this._renderResults(places);
  }

  _renderResults(places) {
    this._results = places;
    if (places.length === 0) {
      this._resultsEl.innerHTML = `<li class="search-panel__status">No results</li>`;
      return;
    }
    this._resultsEl.innerHTML = places
      .map((place, i) => `<li class="search-panel__result" data-index="${i}">${escapeHtml(place.display_name)}</li>`)
      .join("");
    this._resultsEl.querySelectorAll(".search-panel__result").forEach((el) => {
      el.addEventListener("click", () => {
        const place = this._results[Number(el.dataset.index)];
        this._jumpTo(Number(place.lat), Number(place.lon));
      });
    });
  }

  _jumpTo(lat, lng) {
    this._map.flyTo({ center: [lng, lat], zoom: Math.max(this._map.getZoom(), 14) });
    this._panel.hidden = true;
    this._button.classList.remove("active");
  }
}