'use client';

import { useEffect, useMemo, useState, useCallback, useRef } from 'react';
import { MapContainer, TileLayer, Marker, Popup, Polyline, useMap } from 'react-leaflet';
import { OrderItem, Supplier, DriverLocation } from '@/lib/types';
import { formatCurrency, calculateDistance, parseCoordinates } from '@/lib/utils';
import { getDriverTrail, isAuthenticated, getCurrentUser } from '@/lib/pocketbase';
import { Navigation, AlertTriangle, Route, Crosshair, Layers } from 'lucide-react';
import L from 'leaflet';
import 'leaflet/dist/leaflet.css';

const defaultIcon = L.icon({
  iconUrl: 'https://cdnjs.cloudflare.com/ajax/libs/leaflet/1.7.1/images/marker-icon.png',
  iconRetinaUrl: 'https://cdnjs.cloudflare.com/ajax/libs/leaflet/1.7.1/images/marker-icon-2x.png',
  shadowUrl: 'https://cdnjs.cloudflare.com/ajax/libs/leaflet/1.7.1/images/marker-shadow.png',
  iconSize: [25, 41],
  iconAnchor: [12, 41],
  popupAnchor: [1, -34],
  shadowSize: [41, 41],
});

const currentLocationIcon = L.divIcon({
  className: 'custom-div-icon',
  html: `<div style="position:relative;">
    <div style="width:22px;height:22px;background:#ea580c;border:3px solid white;border-radius:50%;box-shadow:0 2px 8px rgba(0,0,0,0.3);position:relative;z-index:2;"></div>
    <div style="width:40px;height:40px;background:rgba(234,88,12,0.15);border-radius:50%;position:absolute;top:-9px;left:-9px;z-index:1;animation:pulse 2s infinite;"></div>
  </div>
  <style>@keyframes pulse{0%,100%{transform:scale(1);opacity:1}50%{transform:scale(1.5);opacity:0}}</style>`,
  iconSize: [22, 22],
  iconAnchor: [11, 11],
});

interface MapViewProps {
  items: OrderItem[];
  onNavigate: (lat: number, lng: number, name: string) => void;
}

function MapBounds({ items }: { items: OrderItem[] }) {
  const map = useMap();
  useEffect(() => {
    const validPoints = items
      .map((i) => {
        const coords = parseCoordinates(i.expand?.supplier?.coordinates);
        return coords ? [coords.latitude, coords.longitude] as [number, number] : null;
      })
      .filter((point): point is [number, number] => point !== null);
    if (validPoints.length > 0) {
      const bounds = L.latLngBounds(validPoints);
      map.fitBounds(bounds, { padding: [60, 60], maxZoom: 15 });
    }
  }, [map, items]);
  return null;
}

function RecenterButton({ center }: { center: [number, number] }) {
  const map = useMap();
  return (
    <button
      onClick={() => map.setView(center, map.getZoom(), { animate: true })}
      className="flex items-center justify-center w-10 h-10 bg-white/90 backdrop-blur-sm rounded-xl shadow-lg active:bg-gray-100 transition-all touch-manipulation press-feedback-sm"
    >
      <Crosshair size={18} className="text-gray-700" />
    </button>
  );
}

export default function CollectionMap({ items, onNavigate }: MapViewProps) {
  const [userLocation, setUserLocation] = useState<[number, number] | null>(null);
  const [trail, setTrail] = useState<[number, number][]>([]);
  const [showTrail, setShowTrail] = useState(true);
  const intervalRef = useRef<ReturnType<typeof setInterval> | null>(null);

  // Get current position
  useEffect(() => {
    if ('geolocation' in navigator) {
      navigator.geolocation.getCurrentPosition(
        (pos) => setUserLocation([pos.coords.latitude, pos.coords.longitude]),
        () => {},
        { enableHighAccuracy: false, timeout: 30000 }
      );
    }
  }, []);

  // Fetch trail data periodically
  const fetchTrail = useCallback(async () => {
    if (!isAuthenticated()) return;
    const user = getCurrentUser();
    if (!user) return;
    const data = await getDriverTrail(user.id);
    const points = data
      .filter((loc) => loc.latitude && loc.longitude)
      .map((loc) => [loc.latitude, loc.longitude] as [number, number]);
    if (points.length > 0) {
      setTrail(points);
    }
  }, []);

  useEffect(() => {
    fetchTrail();
    intervalRef.current = setInterval(fetchTrail, 60000);
    return () => {
      if (intervalRef.current) clearInterval(intervalRef.current);
    };
  }, [fetchTrail]);

  // Group by supplier
  const suppliers = useMemo(() => {
    const map = new Map<string, { supplier: Supplier; items: OrderItem[]; coords: { latitude: number; longitude: number } }>();
    items.forEach((item) => {
      if (!item.expand?.supplier) return;
      const supplier = item.expand.supplier;
      const coords = parseCoordinates(supplier.coordinates);
      if (!coords) return;
      const key = supplier.id;
      if (!map.has(key)) {
        map.set(key, { supplier, items: [], coords });
      }
      map.get(key)!.items.push(item);
    });
    return Array.from(map.values());
  }, [items]);

  const defaultCenter: [number, number] = [-33.9249, 18.4241];
  const center = userLocation || defaultCenter;

  const getDistance = (coords: { latitude: number; longitude: number }) => {
    if (!userLocation) return null;
    return calculateDistance(userLocation[0], userLocation[1], coords.latitude, coords.longitude);
  };

  return (
    <div className="h-full w-full relative">
      <MapContainer center={center} zoom={12} className="h-full w-full" zoomControl={false}>
        <TileLayer
          attribution='&copy; <a href="https://www.openstreetmap.org/copyright">OpenStreetMap</a>'
          url="https://{s}.tile.openstreetmap.org/{z}/{x}/{y}.png"
        />

        <MapBounds items={items} />

        {userLocation && (
          <Marker position={userLocation} icon={currentLocationIcon}>
            <Popup>
              <div className="text-sm font-medium">Your Location</div>
            </Popup>
          </Marker>
        )}

        {/* Trail polyline */}
        {showTrail && trail.length > 1 && (
          <>
            <Polyline
              positions={trail}
              pathOptions={{
                color: '#2563eb',
                weight: 4,
                opacity: 0.7,
                dashArray: '10, 8',
              }}
            />
            <Marker
              position={trail[0]}
              icon={L.divIcon({
                className: '',
                html: '<div style="width:14px;height:14px;background:#22c55e;border:3px solid white;border-radius:50%;box-shadow:0 1px 4px rgba(0,0,0,0.3);"></div>',
                iconSize: [14, 14],
                iconAnchor: [7, 7],
              })}
            >
              <Popup><div className="text-xs font-medium">Trip Start</div></Popup>
            </Marker>
          </>
        )}

        {suppliers.map(({ supplier, items: supplierItems, coords }) => {
          const distance = getDistance(coords);
          return (
            <Marker key={supplier.id} position={[coords.latitude, coords.longitude]} icon={defaultIcon}>
              <Popup>
                <div className="min-w-[200px] max-w-[260px]">
                  <h3 className="font-bold text-sm mb-1">{supplier.suppliername}</h3>
                  {supplier.supplieraddress && (
                    <p className="text-xs text-gray-500 mb-2">{supplier.supplieraddress}</p>
                  )}
                  {distance && (
                    <p className="text-xs text-orange-600 mb-2 font-semibold">
                      {distance < 1 ? `${Math.round(distance * 1000)}m` : `${distance.toFixed(1)} km`} away
                    </p>
                  )}
                  <div className="space-y-1.5 mb-3">
                    {supplierItems.map((i) => (
                      <div key={i.id} className="text-xs p-2 bg-gray-50 rounded-lg">
                        <div className="flex items-center gap-1.5">
                          {(i.item_status === 'problem' || i.problem_flag) && <AlertTriangle size={12} className="text-red-500 flex-shrink-0" />}
                          <span className="font-medium truncate">{i.description}</span>
                        </div>
                        <span className="text-gray-400 text-[11px]">Qty: {i.order_qty || i.quantity || 0}</span>
                      </div>
                    ))}
                  </div>
                  <button
                    onClick={() => onNavigate(coords.latitude, coords.longitude, supplier.suppliername)}
                    className="w-full flex items-center justify-center gap-1.5 py-2 px-3 bg-orange-500 text-white rounded-lg text-sm font-semibold active:bg-orange-600 transition-colors"
                  >
                    <Navigation size={14} /> Navigate
                  </button>
                </div>
              </Popup>
            </Marker>
          );
        })}
      </MapContainer>

      {/* Floating controls */}
      <div className="absolute top-3 right-3 space-y-2 z-[400]">
        {/* Recenter */}
        {userLocation && (
          <RecenterButton center={userLocation} />
        )}

        {/* Trail toggle */}
        {trail.length > 1 && (
          <button
            onClick={() => setShowTrail(!showTrail)}
            className={`flex items-center gap-1.5 px-3 py-2 rounded-xl text-xs font-semibold shadow-lg transition-colors press-feedback-sm ${
              showTrail ? 'bg-blue-500 text-white' : 'bg-white/90 backdrop-blur-sm text-gray-700'
            }`}
          >
            <Route size={14} />
            Trail
          </button>
        )}

        {/* Legend */}
        <div className="bg-white/90 backdrop-blur-sm rounded-xl p-3 shadow-lg">
          <p className="text-[10px] font-bold text-gray-500 uppercase tracking-wider mb-2">Legend</p>
          <div className="space-y-1.5">
            <div className="flex items-center gap-2">
              <div className="w-3 h-3 rounded-full bg-orange-500 border-2 border-white shadow-sm" />
              <span className="text-[11px] text-gray-600">You</span>
            </div>
            <div className="flex items-center gap-2">
              <div className="w-3 h-3.5 bg-blue-900/70 rounded-sm" />
              <span className="text-[11px] text-gray-600">Stop</span>
            </div>
            {trail.length > 1 && (
              <div className="flex items-center gap-2">
                <div className="w-5 h-0" style={{ borderTop: '2px dashed #2563eb' }} />
                <span className="text-[11px] text-gray-600">Route</span>
              </div>
            )}
          </div>
        </div>
      </div>
    </div>
  );
}