feat(classes): implement initiation, start work on dbHelper

lib/main.dart

@@ -6,7 +6,7 @@ import 'transport_helper.dart';
 void main() async {
   await dotenv.load();
   const String dbName = "oeffimasterTransportDb";
-  initDB(dbName);
+  DbHelper.initDb(dbName);
   runApp(const MyApp());
 }
 
@@ -145,4 +145,4 @@ class _MyHomePageState extends State<MyHomePage> {
       ),
     );
   }
-}
+}

lib/transport_helper.dart

@@ -1,48 +1,151 @@
 import 'package:sqflite/sqflite.dart';
+// import './state_helper.dart';
+// import './db_helper.dart';
 
-void initDB(dbName) async {
+// TODO: get access to DB
-  var databasesPath = await getDatabasesPath();
-  var path = databasesPath + dbName;
-  var db = await openDatabase(path);
-  // var db = await openDatabase('/var/db/oeffimaster/transport_db.db');
 
-  // TODO: Make sure the directory exists
+class DbHelper {
+  static late Database db;
+  static String dbName = "";
 
-  // TODO: future optimisation: batch transactions
+  // DbHelper({
+  //   required this.db,
+  //   required this.dbName,
+  // });
 
-  // TODO: create tables for all classes
+  // remnant from when DB was not static
-  // - [] route
+  // factory DbHelper._openDb(Database database, String dbName) => DbHelper(
-  // - [] segment
+  //   db: database,
-  // - [] station
+  //   dbName: dbName,
-  // - [] vehicle
+  // );
-  // - [] line
+
-  // - [] departure
+  static void initDb(String dbName) async {
+    // var db = await openDatabase('/var/db/oeffimaster/transport_db.db');
+    var databasesPath = await getDatabasesPath();
+    var path = databasesPath + dbName;
+    // var newDb = await openDatabase(path);
+    // var dbHelper = DbHelper._openDb(newDb, dbName);
+    db = await openDatabase(path);
+    dbName = dbName;
+
+    // TODO: Make sure the directory exists
+
+    // TODO: future optimisation: batch transactions
+
+    Route.initRouteTable();
+    Segment.initSegmentTable();
+    Station.initStationTable();
+    Vehicle.initVehicleTable();
+    Departure.initDepartureTable();
+    Route.updateHighestId();
+  }
 }
 
 class Route {
+  static int highestId = 0;
+  static const String tableName = "route";
+
+  int id;
   List<Segment> segments = List.empty();
   Duration duration = Duration(minutes: 0);
 
   Route({
+    required this.id,
     required this.segments,
     required this.duration,
   });
 
   // from trip API request
-  factory Route.fromJson(Map<String, dynamic> json) => Route(
+  // TODO: how to connect this best with the database for read/write?
-    segments: json["LegList"]["Leg"].map((leg) => Segment.fromJson(leg)),
+  factory Route.fromJson(Map<String, dynamic> json) {
-    duration:
+    Route newRoute = Route(
-        json["LegList"]["Leg"][-1]["Origin"]["time"] -
+      id: highestId,
-        json["LegList"]["Leg"][0]["Origin"]["time"],
+      segments: json["LegList"]["Leg"].map((leg) => Segment.fromJson(leg)),
-  );
+      duration:
+          json["LegList"]["Leg"][-1]["Origin"]["time"] -
+          json["LegList"]["Leg"][0]["Origin"]["time"],
+    );
+    highestId += 1;
+    return newRoute;
+  }
 
-  // TODO: do we need route in the database???? // what beyond and ID is needed?
+  // rowids will give us new ids for every route-segment connection, but routeid
-  void initRouteTable(Database database) async {
+  // is needed as well, so how do we create these - query highest existing routeid? I think so
-    database.execute("CREATE TABLE IF NOT EXISTS route();");
+  // TODO: get highest routeid in route table (fast)
+  static void initRouteTable() async {
+    Database database = DbHelper.db;
+    database.execute("""CREATE TABLE IF NOT EXISTS routesegments(
+    id       TEXT,
+    segmentid     INTEGER,
+    segmentorder  INTEGER, -- TODO: implement sorting
+    FOREIGN KEY(segmentid) REFERENCES segment(id)
+    );
+    """);
+  }
+
+  static void updateHighestId() async {
+    Database database = DbHelper.db;
+    int newHigh = await getHighestId();
+    highestId = newHigh + 1;
+  }
+
+  /* TODO: better separation between production db and test db
+  *   they share the highestId field regardless, which wont do
+  *   so is an attribut for database needed?
+  */
+
+  /// parse the highest id from the database to continue with ongoing ids but
+  /// create the db entry after the class, for now
+
+  // -- this might be making it more complicated than it needs to be
+  static Future<int> getHighestId() async {
+    Database database = DbHelper.db;
+    try {
+      var tmp = await database.query(
+        "routesegments",
+        columns: ["id"],
+        distinct: true,
+        orderBy: "id",
+        whereArgs: ["id"],
+        limit: 1,
+      );
+      if (tmp.isEmpty) {
+        return 0;
+      }
+      if (tmp[0].isEmpty) {
+        return 0;
+      }
+      // entry "routeid" should definitely exist
+      assert(tmp[0]["id"] != null);
+
+      // Source - https://stackoverflow.com/a/52632172
+      // Posted by Günter Zöchbauer, modified by community. See post 'Timeline' for change history
+      // Retrieved 2026-06-08, License - CC BY-SA 4.0
+      T? cast<T>(x) => x is T ? x : null;
+      // --
+      //doing this in two steps go deal with nullability
+      String highestId = cast<String>(tmp[0]["routeid"]) ?? "0";
+      return int.parse(highestId);
+    } catch (e) {
+      print('Error: Could not get id: $e'); // TODO: use logging
+    }
+    return 0;
+  }
+
+  void writeNewToTable(Route route) async {
+    Database database = DbHelper.db;
+    for (var i = 0; i < route.segments.length; i++) {
+      database.insert("routesegments", {
+        "id": route.id,
+        "segmentid": route.segments[i].id,
+        "segmentorder": i,
+      });
+    }
   }
 }
 
 class Segment {
+  final int id = 0;
   final Station startPoint;
   final Station endPoint;
   final DateTime startTime;
@@ -57,15 +160,21 @@ class Segment {
     required this.vehicle,
   });
 
-  factory Segment.fromJson(Map<String, dynamic> json) => Segment(
+  factory Segment.fromJson(Map<String, dynamic> json) {
-    startPoint: Station.fromJson(json["Origin"]),
+    Database database = DbHelper.db;
-    endPoint: Station.fromJson(json["Destination"]),
+    Segment tmp = Segment(
-    startTime: json["Origin"]["rtTime"],
+      startPoint: Station.fromJson(json["Origin"]),
-    endTime: json["Destination"]["rtTime"],
+      endPoint: Station.fromJson(json["Destination"]),
-    vehicle: Vehicle.fromJson(json["Product"]),
+      startTime: json["Origin"]["rtTime"],
-  );
+      endTime: json["Destination"]["rtTime"],
+      vehicle: Vehicle.fromJson(json["Product"]),
+    );
+    tmp.writeNewToTable(); // TODO: we need to write to db and get the ID!!!!!!!
+    return tmp;
+  }
 
-  void initSegmentTable(Database database) async {
+  static void initSegmentTable() async {
+    Database database = DbHelper.db;
     database.execute("""
     CREATE TABLE IF NOT EXISTS segment(
     startpoint  TEXT,
@@ -74,26 +183,38 @@ class Segment {
     endtime     TEXT,
     vehicle     INTEGER,
     FOREIGN KEY(startpoint) REFERENCES station(stationid),
-    FOREIGN KEY(endpoint) REFERENCES station(stationid)
+    FOREIGN KEY(endpoint) REFERENCES station(stationid),
     FOREIGN KEY(vehicle) REFERENCES vehicle(vehicleid)
     );
     """);
   }
+
+  Future<int> writeNewToTable() async {
+    Database database = DbHelper.db;
+    int id = await database.insert("segment", {
+      "startpoint": startPoint.id,
+      "endpoint": startPoint.id,
+      "startTime": startTime,
+      "endTime": endTime,
+      "vehicle": vehicle.id,
+    });
+    return id;
+  }
 }
 
 class Station {
-  final String stationId;
+  final String id;
   final String name;
   List<Line>? transportLines; // could be normalized away
 
   Station({
-    required this.stationId,
+    required this.id,
     required this.name,
     required this.transportLines, //TODO: make extra db table
   });
 
   factory Station.fromJson(Map<String, dynamic> json) => Station(
-    stationId: json["id"] as String? ?? json["extId"] as String,
+    id: json["id"] as String? ?? json["extId"] as String,
     name: json["name"],
     transportLines: json.containsKey("productAtStop")
         ? json["productAtStop"].map(
@@ -102,9 +223,10 @@ class Station {
         : const [],
   );
 
-  void initStationTable(Database database) async {
+  static void initStationTable() async {
+    Database database = DbHelper.db;
     database.execute("""CREATE TABLE IF NOT EXISTS station(
-      stationid TEXT PRIMARY KEY,
+      id TEXT PRIMARY KEY,
       name      TEXT
     );
     """);
@@ -112,24 +234,25 @@ class Station {
 }
 
 class Vehicle {
-  final String vehicleId;
+  final String id;
   final Line line;
 
   Vehicle({
-    required this.vehicleId,
+    required this.id,
     required this.line,
   });
 
   // we can use the "product" class from within any JSON response
   // (within hafas API, on the appropriate level)
   factory Vehicle.fromJson(Map<String, dynamic> json) => Vehicle(
-    vehicleId: json["matchId"],
+    id: json["matchId"],
     line: Line.fromJson(json),
   );
 
-  void initVehicleTable(Database database) async {
+  static void initVehicleTable() async {
+    Database database = DbHelper.db;
     database.execute("""CREATE TABLE IF NOT EXISTS vehicle(
-      vehicleid TEXT PRIMARY KEY,
+      id TEXT PRIMARY KEY,
       line      TEXT,
       FOREIGN KEY(line) REFERENCES line(lineid)
     );
@@ -138,7 +261,7 @@ class Vehicle {
 }
 
 class Line {
-  final String lineId;
+  final String id;
   Station? destination;
   Station? direction;
   final VehicleType mode;
@@ -147,7 +270,7 @@ class Line {
   Color? bgColor;
 
   Line({
-    required this.lineId,
+    required this.id,
     required this.name,
     required this.mode,
     this.fgColor,
@@ -163,7 +286,7 @@ class Line {
   ];
 
   factory Line.fromJson(Map<String, dynamic> json) => Line(
-    lineId: json["lineId"],
+    id: json["lineId"],
     name: json["name"],
     mode: _vehicleTypeAsCatCode[int.parse(json["catCode"])],
     fgColor:
@@ -173,7 +296,8 @@ class Line {
         Color.fromJson(json["backgroundColor"]) as Color? ??
         Color(r: 50, g: 50, b: 50), // fallback
   );
-  void initLineTable(Database database) async {
+  static void initLineTable() async {
+    Database database = DbHelper.db;
     database.execute("""CREATE TABLE IF NOT EXISTS line(
       lineid      TEXT PRIMARY KEY,
       destination TEXT,
@@ -199,14 +323,15 @@ class Departure {
     required this.departureTime,
   });
 
-  void initDepartureTable(Database database) async {
+  static void initDepartureTable() async {
+    Database database = DbHelper.db;
     database.execute("""CREATE TABLE IF NOT EXISTS departure(
-      departureid     INTEGER,
+      id     INTEGER,
       vehicle         TEXT,
       station         TEXT,
-      departuretime   TEXT
+      departuretime   TEXT,
-      FOREIGN KEY(vehicle) REFERENCES vehicle(vehicleid),
+      FOREIGN KEY(vehicle) REFERENCES vehicle(id),
-      FOREIGN KEY(station) REFERENCES station(stationid)
+      FOREIGN KEY(station) REFERENCES station(id)
      );
      """);
   }