'use client';

/* eslint-disable import-x/no-named-as-default-member */
import mapboxgl from 'mapbox-gl';
import * as React from 'react';
import 'mapbox-gl/dist/mapbox-gl.css';
import { useMapboxStyle } from '@/lib/mapbox-style';
import { cn } from '@/lib/utils';
import { type POIItem, type POICategory, POI_CATEGORY_CONFIG } from './types';

// ── Mapbox layer IDs ──────────────────────────────────────────────────────────
const SOURCE_ID = 'poi-source';
const LAYER_CLUSTERS = 'poi-clusters';
const LAYER_CLUSTER_COUNT = 'poi-cluster-count';
const LAYER_UNCLUSTERED = 'poi-unclustered';

/**
 * Color lookup per POI category — kept in sync with `POI_CATEGORY_CONFIG`.
 * Used in Mapbox `match` expressions so the map layer drives coloring without
 * requiring separate image assets for each category.
 */
const CATEGORY_COLORS: Record<POICategory, string> = {
  school: '#3B82F6',
  hospital: '#EF4444',
  transit: '#8B5CF6',
  shopping: '#F59E0B',
  restaurant: '#F97316',
  park: '#22C55E',
};

/** Build a GeoJSON FeatureCollection from `pois`, filtered to `activeCategories`. */
function buildGeoJson(
  pois: POIItem[],
  activeCategories: Set<POICategory>,
): GeoJSON.FeatureCollection {
  return {
    type: 'FeatureCollection',
    features: pois
      .filter((poi) => activeCategories.has(poi.category))
      .map((poi) => ({
        type: 'Feature' as const,
        geometry: { type: 'Point' as const, coordinates: [poi.lng, poi.lat] },
        properties: {
          id: poi.id,
          name: poi.name,
          category: poi.category,
          categoryLabel: POI_CATEGORY_CONFIG[poi.category].label,
          distance: poi.distance ?? null,
        },
      })),
  };
}

interface NeighborhoodPOIMapProps {
  center: { lat: number; lng: number };
  pois: POIItem[];
  zoom?: number;
  height?: string;
  className?: string;
}

export function NeighborhoodPOIMap({
  center,
  pois,
  zoom = 14,
  height = '400px',
  className,
}: NeighborhoodPOIMapProps) {
  const mapContainerRef = React.useRef<HTMLDivElement>(null);
  const mapRef = React.useRef<mapboxgl.Map | null>(null);
  const centerMarkerRef = React.useRef<mapboxgl.Marker | null>(null);
  const mapStyle = useMapboxStyle();
  const [mapLoaded, setMapLoaded] = React.useState(false);

  const [activeCategories, setActiveCategories] = React.useState<Set<POICategory>>(
    () => new Set(Object.keys(POI_CATEGORY_CONFIG) as POICategory[]),
  );

  const toggleCategory = React.useCallback((category: POICategory) => {
    setActiveCategories((prev) => {
      const next = new Set(prev);
      if (next.has(category)) {
        next.delete(category);
      } else {
        next.add(category);
      }
      return next;
    });
  }, []);

  // ── Initialize map ──────────────────────────────────────────────────────────
  React.useEffect(() => {
    if (!mapContainerRef.current) return;

    const token = process.env['NEXT_PUBLIC_MAPBOX_TOKEN'];
    if (!token) return;

    mapboxgl.accessToken = token;

    const map = new mapboxgl.Map({
      container: mapContainerRef.current,
      style: mapStyle,
      center: [center.lng, center.lat],
      zoom,
      attributionControl: false,
    });

    map.addControl(new mapboxgl.NavigationControl(), 'top-right');
    map.addControl(new mapboxgl.AttributionControl({ compact: true }), 'bottom-right');

    map.on('load', () => setMapLoaded(true));

    mapRef.current = map;

    return () => {
      map.remove();
      mapRef.current = null;
      setMapLoaded(false);
    };
    // eslint-disable-next-line react-hooks/exhaustive-deps
  }, []);

  // ── Re-apply style and rebuild state on theme change ────────────────────────
  React.useEffect(() => {
    const map = mapRef.current;
    if (!map) return;
    setMapLoaded(false);
    map.setStyle(mapStyle);
    const onStyleLoad = () => setMapLoaded(true);
    map.once('style.load', onStyleLoad);
    return () => {
      map.off('style.load', onStyleLoad);
    };
  }, [mapStyle]);

  // ── Fly to center when prop changes ─────────────────────────────────────────
  React.useEffect(() => {
    mapRef.current?.flyTo({ center: [center.lng, center.lat], zoom });
  }, [center, zoom]);

  // ── Property centre marker (DOM, single, no clustering) ─────────────────────
  React.useEffect(() => {
    const map = mapRef.current;
    if (!map || !mapLoaded) return;

    centerMarkerRef.current?.remove();

    const el = document.createElement('div');
    el.style.cssText = `
      width: 16px; height: 16px; border-radius: 50%;
      background: hsl(var(--primary));
      border: 3px solid white;
      box-shadow: 0 0 0 2px hsl(var(--primary)), 0 2px 8px rgba(0,0,0,0.3);
    `;

    centerMarkerRef.current = new mapboxgl.Marker({ element: el, anchor: 'center' })
      .setLngLat([center.lng, center.lat])
      .addTo(map);

    return () => {
      centerMarkerRef.current?.remove();
      centerMarkerRef.current = null;
    };
  }, [mapLoaded, center]);

  // ── POI GeoJSON source + cluster layers ─────────────────────────────────────
  React.useEffect(() => {
    const map = mapRef.current;
    if (!map || !mapLoaded) return;

    const geoJson = buildGeoJson(pois, activeCategories);

    // If the source already exists (e.g. category toggle or pois prop update)
    // just refresh the data — no need to recreate layers.
    const existing = map.getSource(SOURCE_ID) as mapboxgl.GeoJSONSource | undefined;
    if (existing) {
      existing.setData(geoJson);
      return;
    }

    // ── GeoJSON source with built-in clustering ──────────────────────────────
    map.addSource(SOURCE_ID, {
      type: 'geojson',
      data: geoJson,
      cluster: true,
      clusterMaxZoom: 13, // stop clustering above zoom 13
      clusterRadius: 50,  // pixels radius for merging
    });

    // ── Cluster bubble ───────────────────────────────────────────────────────
    map.addLayer({
      id: LAYER_CLUSTERS,
      type: 'circle',
      source: SOURCE_ID,
      filter: ['has', 'point_count'],
      paint: {
        // Small clusters: primary; medium: amber; large: red
        'circle-color': [
          'step',
          ['get', 'point_count'],
          'hsl(var(--primary))',
          5,
          '#f59e0b',
          20,
          '#ef4444',
        ],
        'circle-radius': [
          'step',
          ['get', 'point_count'],
          18, // < 5
          5,
          24, // 5–19
          20,
          32, // ≥ 20
        ],
        'circle-stroke-width': 2,
        'circle-stroke-color': 'white',
        'circle-opacity': 0.9,
      },
    });

    // ── Cluster count label ──────────────────────────────────────────────────
    map.addLayer({
      id: LAYER_CLUSTER_COUNT,
      type: 'symbol',
      source: SOURCE_ID,
      filter: ['has', 'point_count'],
      layout: {
        'text-field': '{point_count_abbreviated}',
        'text-font': ['DIN Offc Pro Medium', 'Arial Unicode MS Bold'],
        'text-size': 12,
      },
      paint: {
        'text-color': '#ffffff',
      },
    });

    // ── Individual POI circle (unclustered) ──────────────────────────────────
    map.addLayer({
      id: LAYER_UNCLUSTERED,
      type: 'circle',
      source: SOURCE_ID,
      filter: ['!', ['has', 'point_count']],
      paint: {
        'circle-radius': 10,
        'circle-color': [
          'match',
          ['get', 'category'],
          'school',     CATEGORY_COLORS.school,
          'hospital',   CATEGORY_COLORS.hospital,
          'transit',    CATEGORY_COLORS.transit,
          'shopping',   CATEGORY_COLORS.shopping,
          'restaurant', CATEGORY_COLORS.restaurant,
          'park',       CATEGORY_COLORS.park,
          '#888888',
        ],
        'circle-stroke-width': 2,
        'circle-stroke-color': 'white',
        'circle-opacity': 0.95,
      },
    });

    // ── Click cluster → zoom in / expand ────────────────────────────────────
    map.on('click', LAYER_CLUSTERS, (e) => {
      const features = map.queryRenderedFeatures(e.point, { layers: [LAYER_CLUSTERS] });
      if (!features.length) return;
      const clusterId = features[0]?.properties?.['cluster_id'] as number;
      (map.getSource(SOURCE_ID) as mapboxgl.GeoJSONSource).getClusterExpansionZoom(
        clusterId,
        (err, expansionZoom) => {
          if (err || expansionZoom == null) return;
          const coords = (features[0]?.geometry as GeoJSON.Point).coordinates as [number, number];
          map.easeTo({ center: coords, zoom: expansionZoom });
        },
      );
    });

    // ── Click unclustered POI → popup ────────────────────────────────────────
    map.on('click', LAYER_UNCLUSTERED, (e) => {
      const features = map.queryRenderedFeatures(e.point, { layers: [LAYER_UNCLUSTERED] });
      if (!features.length) return;
      const { name, categoryLabel, distance } = features[0]?.properties ?? {};
      const coords = (features[0]?.geometry as GeoJSON.Point).coordinates.slice() as [
        number,
        number,
      ];
      new mapboxgl.Popup({ closeButton: true, closeOnClick: true, offset: 12 })
        .setLngLat(coords)
        .setHTML(
          `<div style="font-family:system-ui,sans-serif;padding:8px 10px;border-radius:6px;">
            <p style="font-weight:600;font-size:13px;margin:0 0 2px;">${name}</p>
            <p style="font-size:12px;color:hsl(var(--muted-foreground));margin:0;">${categoryLabel}${distance ? ` · ${distance}m` : ''}</p>
          </div>`,
        )
        .addTo(map);
    });

    // ── Cursor changes ───────────────────────────────────────────────────────
    map.on('mouseenter', LAYER_CLUSTERS, () => {
      map.getCanvas().style.cursor = 'pointer';
    });
    map.on('mouseleave', LAYER_CLUSTERS, () => {
      map.getCanvas().style.cursor = '';
    });
    map.on('mouseenter', LAYER_UNCLUSTERED, () => {
      map.getCanvas().style.cursor = 'pointer';
    });
    map.on('mouseleave', LAYER_UNCLUSTERED, () => {
      map.getCanvas().style.cursor = '';
    });
  }, [mapLoaded, pois, activeCategories]);

  const hasToken = typeof process !== 'undefined' && process.env['NEXT_PUBLIC_MAPBOX_TOKEN'];

  const allCategories = Object.entries(POI_CATEGORY_CONFIG) as [
    POICategory,
    (typeof POI_CATEGORY_CONFIG)[POICategory],
  ][];

  return (
    <div className={cn('relative overflow-hidden rounded-lg border', className)}>
      <div ref={mapContainerRef} style={{ height }} className="w-full" />

      {/* Layer toggle controls */}
      <div className="absolute left-3 top-3 flex flex-col gap-1.5">
        {allCategories.map(([key, config]) => {
          const isActive = activeCategories.has(key);
          const poiCount = pois.filter((p) => p.category === key).length;
          return (
            <button
              key={key}
              type="button"
              onClick={() => toggleCategory(key)}
              className={cn(
                'flex items-center gap-1.5 rounded-full px-2.5 py-1 text-xs font-medium shadow-sm transition-all',
                isActive
                  ? 'bg-card text-card-foreground ring-1 ring-inset ring-border'
                  : 'bg-card/60 text-muted-foreground line-through ring-1 ring-inset ring-transparent',
              )}
              title={`${isActive ? 'Ẩn' : 'Hiện'} ${config.label}`}
            >
              <config.icon className="h-3.5 w-3.5" aria-hidden="true" />
              <span>{config.label}</span>
              {poiCount > 0 && (
                <span
                  className={cn(
                    'ml-0.5 inline-flex h-4 min-w-4 items-center justify-center rounded-full px-1 text-[10px] font-bold',
                    isActive
                      ? 'bg-primary/10 text-primary'
                      : 'bg-muted text-muted-foreground',
                  )}
                >
                  {poiCount}
                </span>
              )}
            </button>
          );
        })}
      </div>

      {/* Fallback when no Mapbox token */}
      {!hasToken && (
        <div
          className="absolute inset-0 flex items-center justify-center bg-gradient-to-b from-blue-50 to-green-50"
          style={{ height }}
        >
          <div className="text-center">
            <svg
              className="mx-auto mb-2 h-10 w-10 text-muted-foreground"
              fill="none"
              stroke="currentColor"
              viewBox="0 0 24 24"
            >
              <path
                strokeLinecap="round"
                strokeLinejoin="round"
                strokeWidth={1.5}
                d="M17.657 16.657L13.414 20.9a1.998 1.998 0 01-2.827 0l-4.244-4.243a8 8 0 1111.314 0z"
              />
              <path
                strokeLinecap="round"
                strokeLinejoin="round"
                strokeWidth={1.5}
                d="M15 11a3 3 0 11-6 0 3 3 0 016 0z"
              />
            </svg>
            <p className="text-sm text-muted-foreground">
              Thiết lập NEXT_PUBLIC_MAPBOX_TOKEN để hiển thị bản đồ POI
            </p>
          </div>
        </div>
      )}
    </div>
  );
}
