main_layout.dart

import 'dart:io';
import 'dart:convert';
import 'dart:typed_data';
import 'package:flutter/material.dart';
import 'package:google_fonts/google_fonts.dart';
import 'package:path_provider/path_provider.dart';
import 'package:shared_preferences/shared_preferences.dart';

import 'osm_layer.dart';
import 'stat_charts.dart';
import '../../consts.dart';
import 'choropleth_map.dart';
import '../data_classes.dart';
import 'satellite_layer.dart';
import 'quick_view_chart.dart';
import '../utils/format_month.dart';

/// MapContainerWidget is the main widget that contains the map with all
/// its layers, polygons and markers.
class MapContainerWidget extends StatefulWidget {
  final List<Measurement> measurements;
  final  Uint8List relation;
  final bool serverConnection;

  const MapContainerWidget({Key? key,
    required this.measurements,
    required this.relation,
    required this.serverConnection,
  }) : super(key: key);

  @override
  _MapContainerWidgetState createState() => _MapContainerWidgetState();
}

class _MapContainerWidgetState extends State<MapContainerWidget> {
  bool isMinimized = true;      // Quick view box state tacker

  bool satLayer = false;        // Satellite layer visibility state
  bool osmLayer = false;        // OSM layer visibility state

  bool isSatTapped = false;        // Satellite button tap state tracker
  bool isMapTapped = false;        // OSM button tap state tracker

  Measurement? selectedMeasurement = selectedMarkerList[0];

  // Initialise lastUpdate variable from persistent storage if server fetch fails
  Future<void> checkAndSetLastUpdate() async {
    if (lastUpdate == null) {
      final prefs = await SharedPreferences.getInstance();
      final updateString = prefs.getString('lastUpdate');

      if (updateString != null && updateString.isNotEmpty) {
        final updateData = DateTime.parse(updateString);
        setState(() {
          lastUpdate = updateData;
        });
      }
    }
  }

  // Tile selection handler
  void handleSelection(int index) {
    String indexString = index.toString();
    setState(() {
      for (Measurement measurement in widget.measurements) {
        for (SubDiv subdivision in measurement.subDivs) {
          if (subdivision.sub_div_id == indexString) {
            selectedSubDiv = subdivision;
            selectedMeasurement = measurement;
            break;