"use client";

import { useMemo, useState } from "react";
import { LoaderCircle, MapPin, Search, X } from "lucide-react";
import { useLocationSearch } from "@/hooks/use-location-search";
import { useWeatherStore } from "@/lib/store";
import { findNearestSynopStation, locateSynopStations } from "@/lib/location-utils";
import { useI18n } from "@/lib/i18n";
import type { MeteoStationPosition, SynopStation } from "@/types/imgw";

export function LocationSearch({ stations, positions }: { stations: SynopStation[]; positions: MeteoStationPosition[] }) {
  const { language, t } = useI18n();
  const [query, setQuery] = useState("");
  const [isFocused, setIsFocused] = useState(false);
  const selectedLocation = useWeatherStore((state) => state.selectedLocation);
  const selectLocation = useWeatherStore((state) => state.selectLocation);
  const { data: locations, isFetching, isError } = useLocationSearch(query, language);
  const locatedStations = useMemo(() => locateSynopStations(stations, positions), [positions, stations]);
  const suggestions = useMemo(() => (locations ?? []).map((location) => ({
    location,
    nearest: findNearestSynopStation(location, locatedStations),
  })).filter((suggestion) => suggestion.nearest !== null), [locatedStations, locations]);
  const showSuggestions = isFocused && query.trim().length >= 2;
  const isPreparingStations = positions.length === 0;

  return (
    <section className="relative z-30">
      <div className="glass rounded-[1.75rem] p-3 sm:p-4">
        <div className="flex items-center gap-2 px-1 pb-3">
          <MapPin className="size-4 text-sky-700 dark:text-sky-300" />
          <p className="text-xs font-semibold uppercase tracking-[0.16em] text-sky-700 dark:text-sky-300">{t("location.label")}</p>
        </div>
        <label className="relative block">
          <span className="sr-only">{t("location.searchLabel")}</span>
          {isFetching || isPreparingStations ? <LoaderCircle className="pointer-events-none absolute left-3.5 top-1/2 size-4 -translate-y-1/2 animate-spin text-sky-600" /> : <Search className="pointer-events-none absolute left-3.5 top-1/2 size-4 -translate-y-1/2 text-slate-500" />}
          <input
            value={query}
            onChange={(event) => setQuery(event.target.value)}
            onFocus={() => setIsFocused(true)}
            onBlur={() => window.setTimeout(() => setIsFocused(false), 150)}
            placeholder={t("location.placeholder")}
            autoComplete="off"
            className="w-full rounded-2xl border border-white/40 bg-white/55 py-3.5 pl-10 pr-10 text-sm placeholder:text-slate-500 focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-sky-500 dark:border-white/10 dark:bg-white/10"
          />
          {query && <button type="button" aria-label={t("location.clear")} onClick={() => setQuery("")} className="absolute right-3 top-1/2 -translate-y-1/2 rounded-full p-1 text-slate-500 transition hover:bg-white/50 focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-sky-500 dark:hover:bg-white/10"><X className="size-4" /></button>}
        </label>
        {selectedLocation && (
          <p className="mt-3 px-1 text-xs text-slate-600 dark:text-slate-300">
            {t("location.currentSource", { location: selectedLocation.name, station: selectedLocation.stationName, distance: selectedLocation.distanceKm })}
          </p>
        )}
        <p className="mt-3 px-1 text-[0.68rem] text-slate-500 dark:text-slate-400">
          {t("location.attribution")} <a href="https://open-meteo.com/en/docs/geocoding-api" target="_blank" rel="noreferrer" className="underline decoration-slate-400/60 underline-offset-2 transition hover:text-sky-700 dark:hover:text-sky-300">Open-Meteo / GeoNames</a>
        </p>
      </div>
      {showSuggestions && (
        <div className="glass absolute inset-x-0 top-[calc(100%+0.5rem)] overflow-hidden rounded-[1.5rem] p-2 shadow-glass">
          {isPreparingStations ? <p className="px-3 py-4 text-sm text-slate-600 dark:text-slate-300">{t("location.preparing")}</p> :
            isError ? <p className="px-3 py-4 text-sm text-slate-600 dark:text-slate-300">{t("location.error")}</p> :
            !isFetching && !suggestions.length ? <p className="px-3 py-4 text-sm text-slate-600 dark:text-slate-300">{t("location.empty")}</p> :
              suggestions.map(({ location, nearest }) => nearest && (
                <button
                  type="button"
                  key={location.id}
                  onClick={() => {
                    selectLocation(nearest);
                    setQuery("");
                    setIsFocused(false);
                  }}
                  className="flex w-full items-start justify-between gap-3 rounded-2xl px-3 py-3 text-left transition hover:bg-white/50 focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-sky-500 dark:hover:bg-white/10"
                >
                  <span>
                    <span className="block text-sm font-semibold">{location.name}</span>
                    <span className="mt-0.5 block text-xs text-slate-500 dark:text-slate-400">{[location.district, location.province].filter(Boolean).join(" · ")}</span>
                  </span>
                  <span className="shrink-0 text-right text-[0.68rem] leading-5 text-slate-500 dark:text-slate-400">{t("location.nearest")}<br /><strong className="font-semibold text-slate-700 dark:text-slate-200">{nearest.stationName} · {nearest.distanceKm} km</strong></span>
                </button>
              ))}
        </div>
      )}
    </section>
  );
}
