Resolves #306 Improve camera connection

lib/entity_widgets/controls/camera_controls.dart

@@ -1,149 +0,0 @@
-part of '../../main.dart';
-
-class CameraControlsWidget extends StatefulWidget {
-
-  final String url;
-
-  CameraControlsWidget({Key key, @required this.url}) : super(key: key);
-
-  @override
-  _CameraControlsWidgetState createState() => _CameraControlsWidgetState();
-}
-
-class _CameraControlsWidgetState extends State<CameraControlsWidget> {
-
-  @override
-  void initState() {
-    super.initState();
-    _connect();
-  }
-
-  http.Client client;
-  http.StreamedResponse response;
-  List<int> binaryImage = [];
-  String cameraState = "Connecting...";
-  bool timeToStop = false;
-  Completer streamCompleter;
-
-  void _connect() async {
-    timeToStop = false;
-    client = new http.Client(); // create a client to make api calls
-    http.Request request = new http.Request("GET", Uri.parse(widget.url));  // create get request
-    Logger.d("[Sending] ==> ${widget.url}");
-    response = await client.send(request);
-    setState(() {
-      cameraState = "Starting...";
-    });
-    Logger.d("[Received] <== ${response.headers}");
-    String frameBoundary = response.headers['content-type'].split('boundary=')[1];
-    final int frameBoundarySize = frameBoundary.length;
-    List<int> primaryBuffer=[];
-    int imageSizeStart = 59;
-    int imageSizeEnd = 0;
-    int imageStart = 0;
-    int imageSize = 0;
-    String strBuffer = "";
-    String contentType = "";
-    streamCompleter = Completer();
-    response.stream.transform(
-        StreamTransformer.fromHandlers(
-          handleData: (data, sink) {
-            primaryBuffer.addAll(data);
-            imageStart = 0;
-            imageSizeEnd = 0;
-            if (primaryBuffer.length >= imageSizeStart + 10) {
-              contentType = utf8.decode(
-                  primaryBuffer.sublist(frameBoundarySize+16, imageSizeStart + 10), allowMalformed: true).split("\r\n")[0];
-              //Logger.d("$contentType");
-              imageSizeStart = frameBoundarySize + 16 + contentType.length + 18;
-              for (int i = imageSizeStart; i < primaryBuffer.length - 4; i++) {
-                strBuffer = utf8.decode(
-                    primaryBuffer.sublist(i, i + 4), allowMalformed: true);
-                if (strBuffer == "\r\n\r\n") {
-                  imageSizeEnd = i;
-                  imageStart = i + 4;
-                  break;
-                }
-              }
-              if (imageSizeEnd > 0) {
-                imageSize = int.tryParse(utf8.decode(
-                    primaryBuffer.sublist(imageSizeStart, imageSizeEnd),
-                    allowMalformed: true));
-                //Logger.d("content-length: $imageSize");
-                if (imageSize != null &&
-                    primaryBuffer.length >= imageStart + imageSize + 2) {
-                  sink.add(
-                      primaryBuffer.sublist(
-                          imageStart, imageStart + imageSize));
-                  primaryBuffer.removeRange(0, imageStart + imageSize + 2);
-                }
-              }
-            }
-            if (timeToStop) {
-              sink?.close();
-              streamCompleter.complete();
-            }
-          },
-          handleError: (error, stack, sink) {
-            Logger.e("Error parsing MJPEG stream: $error");
-          },
-          handleDone: (sink) {
-            Logger.d("Camera stream finished. Reconnecting...");
-            sink?.close();
-            streamCompleter?.complete();
-            _reconnect();
-          },
-        )
-    ).listen((d) {
-      if (!timeToStop) {
-        setState(() {
-          binaryImage = d;
-        });
-      }
-    });
-  }
-
-  void _reconnect() {
-    disconnect().then((_){
-      _connect();
-    });
-  }
-
-  Future disconnect() {
-    Completer disconF = Completer();
-    timeToStop = true;
-    if (streamCompleter != null && !streamCompleter.isCompleted) {
-      streamCompleter.future.then((_) {
-        client?.close();
-        disconF.complete();
-      });
-    } else {
-      client?.close();
-      disconF.complete();
-    }
-    return disconF.future;
-  }
-
-  @override
-  Widget build(BuildContext context) {
-    if (binaryImage.isEmpty) {
-      return Column(
-        children: <Widget>[
-          Text("$cameraState")
-        ],
-      );
-    } else {
-      return Column(
-        children: <Widget>[
-          Image.memory(Uint8List.fromList(binaryImage), gaplessPlayback: true),
-        ],
-      );
-    }
-  }
-
-  @override
-  void dispose() {
-    disconnect();
-    super.dispose();
-  }
-}