/**
 * Mapa de features. Dibuja la geometría GeoJSON del proyecto (puntos, líneas,
 * polígonos) sobre Google Maps y permite seleccionar una feature tocándola.
 *
 * Nota: las tiles de Google Maps requieren conexión; la geometría sí se dibuja
 * sin red. Requiere una API key de Google Maps (ver app.config.js / README).
 */
import * as Location from 'expo-location';
import React, { useMemo, useRef } from 'react';
import { StyleSheet, Text, TouchableOpacity, View } from 'react-native';
import MapView, { Marker, Polygon, Polyline, PROVIDER_GOOGLE } from 'react-native-maps';
import { Feature } from '../api/types';
import { COLORS } from './components';
import { geometryToShapes, LatLng, regionFor } from './geojson';

const STATUS_COLOR: Record<string, string> = {
  pending: '#9aa0a6',
  in_progress: '#1f6f43',
  completed: '#2e7d32',
  blocked: '#b00020',
};

function colorFor(status?: string): string {
  return (status && STATUS_COLOR[status]) || COLORS.primary;
}

export function FeatureMap({
  features,
  selectedId,
  onSelect,
}: {
  features: Feature[];
  selectedId: number | null;
  onSelect: (id: number) => void;
}) {
  const mapRef = useRef<MapView>(null);

  const { shaped, region } = useMemo(() => {
    const all: LatLng[] = [];
    const shaped = features.map((f) => {
      const shapes = geometryToShapes(f.geometry);
      all.push(...shapes.points, ...shapes.lines.flat(), ...shapes.polygons.flat());
      return { feature: f, shapes };
    });
    return { shaped, region: regionFor(all) };
  }, [features]);

  const recenter = async () => {
    const perm = await Location.requestForegroundPermissionsAsync();
    if (!perm.granted) return;
    const pos = await Location.getCurrentPositionAsync({});
    mapRef.current?.animateToRegion({
      latitude: pos.coords.latitude,
      longitude: pos.coords.longitude,
      latitudeDelta: 0.01,
      longitudeDelta: 0.01,
    });
  };

  if (!region) {
    return (
      <View style={styles.empty}>
        <Text style={{ color: COLORS.muted }}>Las features no tienen geometría.</Text>
      </View>
    );
  }

  return (
    <View style={styles.container}>
      <MapView
        ref={mapRef}
        style={StyleSheet.absoluteFill}
        provider={PROVIDER_GOOGLE}
        initialRegion={region}
        showsUserLocation
      >
        {shaped.map(({ feature, shapes }) => {
          const color = colorFor(feature.status);
          const selected = feature.id === selectedId;
          const stroke = selected ? '#000' : color;
          return (
            <React.Fragment key={feature.id}>
              {shapes.points.map((p, i) => (
                <Marker
                  key={`pt${feature.id}-${i}`}
                  coordinate={p}
                  pinColor={color}
                  title={feature.name}
                  onPress={() => onSelect(feature.id)}
                />
              ))}
              {shapes.lines.map((line, i) => (
                <Polyline
                  key={`ln${feature.id}-${i}`}
                  coordinates={line}
                  strokeColor={stroke}
                  strokeWidth={selected ? 5 : 3}
                  tappable
                  onPress={() => onSelect(feature.id)}
                />
              ))}
              {shapes.polygons.map((poly, i) => (
                <Polygon
                  key={`pg${feature.id}-${i}`}
                  coordinates={poly}
                  strokeColor={stroke}
                  fillColor={`${color}55`}
                  strokeWidth={selected ? 4 : 2}
                  tappable
                  onPress={() => onSelect(feature.id)}
                />
              ))}
            </React.Fragment>
          );
        })}
      </MapView>

      <TouchableOpacity style={styles.locBtn} onPress={() => void recenter()}>
        <Text style={styles.locIcon}>◎</Text>
      </TouchableOpacity>
    </View>
  );
}

const styles = StyleSheet.create({
  container: { flex: 1 },
  empty: { flex: 1, justifyContent: 'center', alignItems: 'center', padding: 24 },
  locBtn: {
    position: 'absolute',
    right: 16,
    bottom: 16,
    width: 48,
    height: 48,
    borderRadius: 24,
    backgroundColor: '#fff',
    justifyContent: 'center',
    alignItems: 'center',
    elevation: 4,
    shadowColor: '#000',
    shadowOpacity: 0.2,
    shadowRadius: 4,
    shadowOffset: { width: 0, height: 2 },
  },
  locIcon: { fontSize: 22, color: COLORS.primary },
});