import 'dart:convert';
import 'dart:io';
import 'package:xml/xml.dart';



import 'package:http/http.dart' as http;
import 'package:shared_preferences/shared_preferences.dart';

class FetchMenu {
  static var lastFetch = DateTime.now();
  static var fetched = false;

  static Future<List<String>> get() async {
    List<String> menus = [];

    if (!fetched || DateTime.now().difference(lastFetch).inHours >= 2) {
      menus = await fromRequest();
      fetched = true;
    } else {
      menus = await fromCache();
    }

    return menus;
  }

  static Future<List<String>> fromCache() async {
    return await loadCache();
  }

    static Future<List<String>> fromRequest() async {
      List<String> menus = [];
      var now = DateTime.now();
      var today = "${now.day.toString().padLeft(2, '0')}.${now.month.toString().padLeft(2, '0')}.${now.year}";

      http.Response resp = await http.get(Uri.parse(
          "https://www.swfr.de/apispeiseplan?&type=98&tx_speiseplan_pi1[apiKey]=c3841e89a2c8c301b890723ecdb786ad&tx_speiseplan_pi1[ort]=677")); //Api Key lays here, modify this shit when you have time
      var xmlContent = XmlDocument.parse(utf8.decode(resp.bodyBytes));
      for (var tagesplan in xmlContent.findAllElements("tagesplan")){
        var datum = tagesplan.getAttribute('datum')?.trim();
        if (datum == today){
          for (var menu in tagesplan.findElements('menue')){
            var name = menu.findElements('name').map((e) => e.text).join(", ");
            menus.add(name);
          }
        }
      }

    await storeCache(menus);

    lastFetch = DateTime.now();

    return menus;
  }

  static Future<void> storeCache(List<String> menus) async {
    var prefs = await SharedPreferences.getInstance();

    for (var i = 0; i < 4; i++) {
      prefs.setString("menuCache$i", "");
      if (i < menus.length) {
        prefs.setString("menuCache$i", menus[i]);
      }
    }


  }

  static Future<List<String>> loadCache() async {
    var prefs = await SharedPreferences.getInstance();

    List<String> menus = [];

    for (var i = 0; i < 4; i++) {
      var curr = prefs.getString("menuCache$i");
      if (curr != "") {
        menus.add(curr!);
      }
    }

    return menus;
  }
}