拡大縮小機能で試行錯誤 – 開発日記(11)

import 'package:flutter/material.dart';
import 'package:flutter/services.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';
import 'logic_collection.dart';
import 'dart:math';
import 'dart:convert'; //JSON形式のデータを扱う
import 'package:path/path.dart' as path_dart; //asが無いとcontextを上書きされてしまう
import 'package:file_selector/file_selector.dart';

StateProvider<bool> _relatedIdeaSelectMode = StateProvider((ref) => false);
StateProvider<Idea?> _originIdeaForSelectMode = StateProvider((ref) => null);

StateProvider<double> currentScale = StateProvider((ref) => 1);

void main() {
  runApp(ProviderScope(child: MyApp()));
}

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        body: SafeArea(child: WholeZone()),
      ),
    );
  }
}

class WholeZone extends StatefulWidget {
  @override
  _WholeZoneState createState() => _WholeZoneState();
}

class _WholeZoneState extends State<WholeZone> {
  GlobalKey<_CanvasZoneState> canvasZoneKey = GlobalKey();
  late CanvasZone canvasZone;

  @override
  void initState() {
    canvasZone = CanvasZone(key: canvasZoneKey);
    super.initState();
  }

  void scaleUp() {
    if (canvasZoneKey.currentState == null) return;
    TransformationController controller = canvasZoneKey.currentState!._transformationController;
    controller.value = Matrix4.identity()..scale(controller.value.getMaxScaleOnAxis() * 1.1);
  }

  void scaleDown() {
    if (canvasZoneKey.currentState == null) return;
    TransformationController controller = canvasZoneKey.currentState!._transformationController;
    controller.value = Matrix4.identity()..scale(controller.value.getMaxScaleOnAxis() * 0.9);
  }

  Future<void> saveAs() async {
    String? path = await getSavePath(
      acceptedTypeGroups: [
        const XTypeGroup(label: 'json', extensions: ['json'])
      ],
      suggestedName: "",
    );
    if (path != null) {
      if (path_dart.extension(path) == '') {
        path = '$path.json';
      }
      saveData(fileName: path, widget: canvasZone);
    }
  }

  @override
  Widget build(BuildContext context) {
    return Column(children: [
      Align(
        alignment: Alignment.topCenter,
        child: Container(
          margin: const EdgeInsets.only(top: 10),
          child: Row(
            mainAxisAlignment: MainAxisAlignment.center,
            children: [
              ElevatedButton(
                onPressed: canvasZoneKey.currentState?.addNewLane,
                child: const Text("レーン追加"),
              ),
              const SizedBox(width: 10),
              ElevatedButton(
                onPressed: canvasZoneKey.currentState?.removeLane,
                child: const Text("削除"),
              ),
              const SizedBox(width: 30),
              ElevatedButton(
                onPressed: scaleUp,
                child: const Text("拡大"),
              ),
              const SizedBox(width: 10),
              ElevatedButton(
                onPressed: scaleDown,
                child: const Text("縮小"),
              ),
              const SizedBox(width: 30),
              ElevatedButton(
                onPressed: saveAs,
                child: const Text("名前を付けて保存"),
              ),
              const SizedBox(width: 10),
              ElevatedButton(
                onPressed: canvasZoneKey.currentState?.loadDataWithDialog,
                child: const Text("ファイルを読込"),
              ),
              const SizedBox(width: 30),
              ElevatedButton(
                onPressed: canvasZoneKey.currentState?.test,
                child: const Text("テスト"),
              ),
            ],
          ),
        ),
      ),
      const Divider(),
      Expanded(
          child: canvasZone,
        ),
    ]);
  }
}

class IdeasRelation {
  Idea origin;
  Idea related;
  IdeasRelation({required this.origin, required this.related});
}

class CanvasZone extends StatefulWidget {
  @override
  GlobalKey<_CanvasZoneState> key;

  CanvasZone({required GlobalKey<_CanvasZoneState> this.key}) : super(key: key);

  @override
  State<CanvasZone> createState() => _CanvasZoneState();
}

class _CanvasZoneState extends State<CanvasZone> {
  double widthA = double.infinity;
  List<Lane> lanes = [];
  List<IdeasRelation> relatedIdeasList = [];

  TransformationController _transformationController = TransformationController();

  @override
  void initState() {
    super.initState();
    addNewLane();
    loadData(widget: widget);
    WidgetsBinding.instance.addPostFrameCallback((_) {
      lanes[0].ideas[0].key.currentState?._textFocusNode.requestFocus();
      setState(() {});
    });
  }

  void test() {
    setState(() {});
  }

  Future<void> loadDataWithDialog() async {
    const XTypeGroup typeGroup = XTypeGroup(
      label: 'json',
      extensions: ['json'],
    );
    final XFile? file = await openFile(acceptedTypeGroups: [typeGroup]);
    if (file != null) {
      setState(() {
        loadData(fileName: file.path, widget: widget);
      });
    }
  }

  Future<void> addNewLaneAndFocusTitle(int targetLaneIndex) async {
    if (targetLaneIndex == lanes.length) {
      await addNewLane();
    }
    // ウィジェットが構築されるのを待つ
    WidgetsBinding.instance.addPostFrameCallback((_) {
      lanes[targetLaneIndex].key.currentState?._titleFocusNode.requestFocus();
    });
  }

  Future<void> addNewLane() async {
    setState(() {
      var newLane = Lane(index: lanes.length, ideas: [Idea(index: 0)]);
      lanes.add(newLane);
      newLane.ideas[0].parentLane = newLane;
    });
    WidgetsBinding.instance.addPostFrameCallback((_) {
      lanes[lanes.length - 1].ideas[0].key.currentState?._textFocusNode.requestFocus();
    });
  }

  void removeLane() {
    setState(() {
      if (lanes.length > 1) {
        lanes.removeLast();
      }
    });
  }

  void focusNextLane(int targetLaneIndex, int targetIdeaIndex) {
    if (targetLaneIndex < 0 || targetIdeaIndex < 0) return;
    if (targetLaneIndex == lanes.length) {
      addNewLane();
    }
    if (targetLaneIndex < lanes.length) {
      for (int i = lanes[targetLaneIndex].ideas.length - 1; i < targetIdeaIndex; i++) {
        if (lanes[targetLaneIndex].key.currentState == null) {
          setState(() {
            //addNewIdeaが使えない状態なので、やむなく自力実装
            lanes[targetLaneIndex].ideas.add(Idea(index: i + 1));
            lanes[targetLaneIndex].ideas[lanes[targetLaneIndex].ideas.length - 1].parentLane = lanes[targetLaneIndex];
            for (int j = 0; j < lanes[targetLaneIndex].ideas.length; j++) {
              lanes[targetLaneIndex].ideas[j].index = j;
            }
          });
        } else {
          lanes[targetLaneIndex].key.currentState?.addNewIdea(i);
        }
      }
      lanes[targetLaneIndex].ideas[targetIdeaIndex].key.currentState?._textFocusNode.requestFocus();
    }
  }

  // 関連付けの線を描画する
  void _relationLinePaint(Canvas canvas, Size size) {
    relationLinePaint(canvas, widget);
    //relationLinePaintForDebug(canvas, widget);
  }

  @override
  Widget build(BuildContext context) {
    return CanvasZoneInheritedWidget(
      canvasZoneState: this,
      child: InteractiveViewer(
        constrained: false,
        panEnabled: true,
        scaleEnabled: true,
        minScale: 0.2,
        maxScale: 5.0,
        boundaryMargin: EdgeInsets.all(0), // 縮小を可能にするにはこの設定が必要
        transformationController: _transformationController,
        child: Container( //Canvasのサイズ
          width: MediaQuery.of(context).size.width * 0.4 * lanes.length,
          height: MediaQuery.of(context).size.height, //double.infinity,
          color: Colors.transparent, // カラーを指定しないと上のGestureDetectorの範囲がchildの範囲に収まってしまう
          child: Stack(
            children: [
              ListView.builder( // Laneの横並び
                scrollDirection: Axis.horizontal,
                itemCount: lanes.length,
                itemBuilder: (context, index) {
                  return SizedBox( // Laneごとの箱
                    width: MediaQuery.of(context).size.width * 0.4,
                    child: lanes[index],
                  );
                },
              ),
              CustomPaint(
                painter: _CustomPainterB(_relationLinePaint),
              ),
            ],
          ),
        ),
      ),
    );
  }
}

class CanvasZoneInheritedWidget extends InheritedWidget {
  final _CanvasZoneState canvasZoneState;

  CanvasZoneInheritedWidget({required this.canvasZoneState, required Widget child}) : super(child: child);

  @override
  bool updateShouldNotify(CanvasZoneInheritedWidget oldWidget) => true;

  static _CanvasZoneState of(BuildContext context) {
    return context.dependOnInheritedWidgetOfExactType<CanvasZoneInheritedWidget>()!.canvasZoneState;
  }
}

class Lane extends StatefulWidget {
  @override
  final GlobalKey<_LaneState> key = GlobalKey<_LaneState>();
  int index;
  String title;
  List<Idea> ideas;
  final double indentWidth = 40; //インデントの下げ幅

  Lane({
    required this.index,
    required this.ideas,
    this.title = '',
  }) : super(key: ValueKey(GlobalKey<_LaneState>().toString()));

  @override
  State<Lane> createState() => _LaneState();
}

class _LaneState extends State<Lane> {
  List<Idea> get ideas => widget.ideas;
  final TextEditingController titleController = TextEditingController();
  final FocusNode _titleFocusNode = FocusNode();

  void addNewIdea(int currentIndex) {
    setState(() {
      int currentIndentLevel = ideas[currentIndex].indentLevel;
      ideas.insert(
        currentIndex + 1,
        Idea(
          index: currentIndex + 1,
          parentLane: widget,
          textFieldHeight: 48.0,
          indentLevel: currentIndentLevel,
        ),
      );
      for (int i = currentIndex + 2; i < ideas.length; i++) {
        ideas[i].index = i;
      }
    });

    WidgetsBinding.instance.addPostFrameCallback((_) {
      ideas[currentIndex + 1].key.currentState?._textFocusNode.requestFocus();
    });
  }

  void moveIdea(int currentIndex, int direction) {
    if (currentIndex + direction >= 0 && currentIndex + direction < ideas.length) {
      setState(() {
        Idea temp = ideas[currentIndex];
        ideas[currentIndex] = ideas[currentIndex + direction];
        ideas[currentIndex + direction] = temp;
        ideas[currentIndex].key.currentState?.updateIndex(currentIndex);
        ideas[currentIndex + direction].key.currentState?.updateIndex(currentIndex + direction);
      });
    }
  }

  void deleteIdea(int currentIndex) {
    if (ideas.length > 1) {
      setState(() {
        ideas.removeAt(currentIndex);
        for (int i = currentIndex; i < ideas.length; i++) {
          ideas[i].index = i;
        }
        if (currentIndex > 0) {
          ideas[currentIndex - 1].key.currentState?._textFocusNode.requestFocus();
        } else {
          ideas[currentIndex].key.currentState?._textFocusNode.requestFocus();
        }
      });
    }
  }

  void focusAdjacentIdea(int currentIndex, int direction) {
    if (currentIndex == 0 && direction <= 0) {
      FocusScope.of(context).requestFocus(_titleFocusNode);
    } else if (currentIndex + direction >= 0 && currentIndex + direction < ideas.length) {
      ideas[currentIndex + direction].key.currentState?._textFocusNode.requestFocus();
    }
  }

  void redrawAffectedIdeas(int startIndex, int endIndex) {
    if (startIndex < 0 || endIndex >= ideas.length) return;
    setState(() {
      for (int i = startIndex; i <= endIndex; i++) {
        //再描画を促す
        //ideas[i].key.currentState?.indentLevel = widget.key.currentState?.indentLevel ?? indentLevel;
      }
    });
  }

  @override
  void initState() {
    super.initState();
    titleController.text = widget.title;
  }

  @override
  Widget build(BuildContext context) {
    return LaneInheritedWidget(
      laneState: this,
      child: Column(children: [
        Focus(
            onKey: (FocusNode node, RawKeyEvent event) {
              if (event.runtimeType == RawKeyDownEvent) {
                if (event.logicalKey == LogicalKeyboardKey.arrowDown) {
                  //カーソルキー ↓
                  ideas[0].key.currentState?._textFocusNode.requestFocus();
                } else if (event.logicalKey == LogicalKeyboardKey.arrowRight && //カーソルキー →
                    titleController.selection.baseOffset == titleController.text.length) {
                  CanvasZoneInheritedWidget.of(context).addNewLaneAndFocusTitle(widget.index + 1);
                } else if (event.logicalKey == LogicalKeyboardKey.arrowLeft && //カーソルキー ←
                    titleController.selection.baseOffset == 0) {
                  if (widget.index > 0) {
                    CanvasZoneInheritedWidget.of(context).lanes[widget.index - 1].key.currentState?._titleFocusNode.requestFocus();
                  }
                }
              }
              return KeyEventResult.ignored;
            },
            child: Container(
              color: Colors.blue[50],
              padding: EdgeInsets.symmetric(horizontal: widget.indentWidth),
              child: TextField(
                controller: titleController,
                focusNode: _titleFocusNode,
                decoration: InputDecoration(
                  border: InputBorder.none,
                  disabledBorder: const OutlineInputBorder(
                    borderSide: BorderSide(color: Colors.blue, width: 2.0),
                  ),
                  fillColor: Colors.blue[50],
                  filled: true,
                ),
                style: TextStyle(fontSize: 18.0, fontWeight: FontWeight.bold, color: Colors.blue[900]),
                keyboardType: TextInputType.text,
                textInputAction: TextInputAction.done,
                onSubmitted: (value) {
                  _titleFocusNode.unfocus();
                },
              ),
            )),
        Expanded(
          child: ListView.builder(
            itemCount: ideas.length,
            itemBuilder: (context, index) {
              return ideas[index];
            },
          ),
        ),
      ]),
    );
  }
}

class LaneInheritedWidget extends InheritedWidget {
  final _LaneState laneState;

  LaneInheritedWidget({required this.laneState, required Widget child}) : super(child: child);

  @override
  bool updateShouldNotify(LaneInheritedWidget oldWidget) => true;

  static _LaneState of(BuildContext context) {
    return context.dependOnInheritedWidgetOfExactType<LaneInheritedWidget>()!.laneState;
  }
}

class Idea extends ConsumerStatefulWidget {
  @override
  final GlobalKey<_IdeaState> key = GlobalKey<_IdeaState>();
  int index;
  int indentLevel;
  final double boxSpacing; //他のエディタとの間隔
  final double textFieldHeight; //テキスト欄の高さ
  String content;
  Lane? parentLane;
  List<Idea> relatedIdeas = [];
  GlobalKey textFieldKey = GlobalKey();

  Idea({
    required this.index,
    this.parentLane,
    this.boxSpacing = 8.0,
    this.textFieldHeight = 48.0, //デフォルトは48
    this.indentLevel = 0,
    this.content = '',
  }) : super(key: ValueKey(GlobalKey<_IdeaState>().toString()));

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

class _IdeaState extends ConsumerState<Idea> with AutomaticKeepAliveClientMixin<Idea> {
  final TextEditingController textController = TextEditingController();
  final FocusNode _textFocusNode = FocusNode();

  void updateIndex(int newIndex) {
    setState(() {
      widget.index = newIndex;
    });
  }

  // インデントの線を描画する
  void _indentLinePaint(Canvas canvas, Size size) {
    indentLinePaint(canvas, size, context, widget.index, widget.indentLevel, widget.textFieldHeight, widget.boxSpacing,
        LaneInheritedWidget.of(context).widget.indentWidth);
  }

  String toJson() {
    Map<String, dynamic> data = {
      'index': widget.index,
      'indentLevel': widget.indentLevel,
      'text': textController.text,
    };
    return json.encode(data);
  }

  @override
  void initState() {
    super.initState();
    textController.text = widget.content;
  }

  @override
  bool get wantKeepAlive => true; //これが無いと画面外から出たときに中身も消えてしまう

  @override
  Widget build(BuildContext context) {
    super.build(context);
    return Focus(
        onKey: (FocusNode node, RawKeyEvent event) {
          if (event.runtimeType == RawKeyDownEvent) {
            if (event.logicalKey == LogicalKeyboardKey.capsLock) {
              // CapsLockキーを無視する条件を追加
              return KeyEventResult.ignored;
            } else if (event.isControlPressed) {
              //コントロールキー
              bool needRepaint = false;
              if (event.logicalKey == LogicalKeyboardKey.arrowUp) {
                LaneInheritedWidget.of(context).moveIdea(widget.index, -1);
                needRepaint = true;
              } else if (event.logicalKey == LogicalKeyboardKey.arrowDown) {
                LaneInheritedWidget.of(context).moveIdea(widget.index, 1);
                needRepaint = true;
              }
              if (needRepaint) {
                findAndRepaintAffectedIdeas(context, widget.index, widget.indentLevel, widget.index, widget.index + 1 /*Ctrlキーの場合、１つ下からチェックが必要*/);
              }
            } else if (event.logicalKey == LogicalKeyboardKey.arrowUp) {
              //カーソルキー ↑
              LaneInheritedWidget.of(context).focusAdjacentIdea(widget.index, -1);
            } else if (event.logicalKey == LogicalKeyboardKey.arrowDown) {
              if (widget.index == LaneInheritedWidget.of(context).ideas.length - 1) {
                LaneInheritedWidget.of(context).addNewIdea(widget.index);
              } else {
                LaneInheritedWidget.of(context).focusAdjacentIdea(widget.index, 1);
              }
            } else if (event.logicalKey == LogicalKeyboardKey.arrowRight && //カーソルキー →
                textController.selection.baseOffset == textController.text.length) {
              int laneIndex = CanvasZoneInheritedWidget.of(context).lanes.indexOf(LaneInheritedWidget.of(context).widget);
              CanvasZoneInheritedWidget.of(context).focusNextLane(laneIndex + 1, widget.index);
            } else if (event.logicalKey == LogicalKeyboardKey.arrowLeft && textController.selection.baseOffset == 0) {
              int laneIndex = CanvasZoneInheritedWidget.of(context).lanes.indexOf(LaneInheritedWidget.of(context).widget);
              CanvasZoneInheritedWidget.of(context).focusNextLane(laneIndex - 1, widget.index);
            } else if (event.logicalKey == LogicalKeyboardKey.tab) {
              //TABキー
              if (event.isShiftPressed) {
                setState(() {
                  widget.indentLevel = max(0, widget.indentLevel - 1);
                });
              } else {
                setState(() {
                  widget.indentLevel += 1;
                });
              }
              findAndRepaintAffectedIdeas(context, widget.index, widget.indentLevel, widget.index, widget.index);
              return KeyEventResult.handled; //デフォルトのタブの挙動を無効化して、フォーカスの移動を防ぐ
            } else if ((event.logicalKey == LogicalKeyboardKey.delete || //DEL & BSキー
                    event.logicalKey == LogicalKeyboardKey.backspace) &&
                textController.text.isEmpty) {
              LaneInheritedWidget.of(context).deleteIdea(widget.index);
            } else if (event.logicalKey == LogicalKeyboardKey.f1) {
              StateController<bool> mode = ref.watch(_relatedIdeaSelectMode.notifier);
              mode.state = true;
              ref.watch(_originIdeaForSelectMode.notifier).state = widget;
              ScaffoldMessenger.of(context).showSnackBar(
                SnackBar(
                  content: Text(
                      'IdeaSelectMode:${mode.state} Lane:${CanvasZoneInheritedWidget.of(context).lanes.indexOf(LaneInheritedWidget.of(context).widget)} Idea:${widget.index}'),
                ),
              );
            }
          }
          return KeyEventResult.ignored;
        },
        child: RawKeyboardListener(
          focusNode: FocusNode(),
          child: Container(
            margin: EdgeInsets.symmetric(horizontal: 16, vertical: widget.boxSpacing),
            child: Row(
              crossAxisAlignment: CrossAxisAlignment.center,
              children: [
                const SizedBox(width: 26, child: DecoratedBox(decoration: BoxDecoration(color: Colors.red))),
                Expanded(
                  flex: 4,
                  child: Row(children: [
                    CustomPaint(
                      painter: _CustomPainter(_indentLinePaint),
                      child: Container(width: LaneInheritedWidget.of(context).widget.indentWidth * widget.indentLevel),
                    ),
                    Expanded(
                      child: SizedBox(
                        height: widget.textFieldHeight,
                        child: TextField(
                          key: widget.textFieldKey,
                          controller: textController,
                          focusNode: _textFocusNode,
                          maxLines: 1,
                          decoration: const InputDecoration(
                            border: OutlineInputBorder(),
                          ),
                          keyboardType: TextInputType.multiline,
                          textInputAction: TextInputAction.done,
                          onSubmitted: (value) {
                            Offset? globalOffset;
                            if (ref.watch(_relatedIdeaSelectMode.notifier).state == true) {
                              StateController<bool> mode = ref.watch(_relatedIdeaSelectMode.notifier);
                              Idea? origin = ref.watch(_originIdeaForSelectMode.notifier).state;
                              if (origin != null) {
                                widget.relatedIdeas.add(origin);
                                CanvasZoneInheritedWidget.of(context).widget.key.currentState!.relatedIdeasList.add(IdeasRelation(origin: origin, related: widget));
                                origin = null;
                                RenderBox? box = widget.key.currentContext?.findRenderObject() as RenderBox;
                                globalOffset = box.localToGlobal(Offset.zero);
                              }
                              ScaffoldMessenger.of(context).hideCurrentSnackBar();
                              ScaffoldMessenger.of(context).showSnackBar(
                                SnackBar(
                                  content: Text(
                                      'globaolOffset:$globalOffset | originIndex:${widget.relatedIdeas[0].index}  | Lane:${CanvasZoneInheritedWidget.of(context).lanes.indexOf(LaneInheritedWidget.of(context).widget)} Idea:${widget.index}'),
                                ),
                              );
                              mode.state = false;
                            } else {
                              _textFocusNode.unfocus();
                              LaneInheritedWidget.of(context).addNewIdea(widget.index);
                            }
                          },
                        ),
                      ),
                    ),
                  ]),
                ),
              ],
            ),
          ),
        ));
  }
}

class _CustomPainter extends CustomPainter {
  final void Function(Canvas, Size) _paint;
  _CustomPainter(this._paint);

  @override
  void paint(Canvas canvas, Size size) {
    _paint(canvas, size);
  }

  @override
  bool shouldRepaint(covariant CustomPainter oldDelegate) => false;
}

class _CustomPainterB extends CustomPainter {
  final void Function(Canvas, Size) _paint;
  _CustomPainterB(this._paint);

  @override
  void paint(Canvas canvas, Size size) {
    _paint(canvas, size);
  }

  @override
  bool shouldRepaint(covariant CustomPainter oldDelegate) => false;
}

import 'package:flutter/material.dart';
import 'main.dart';
import 'dart:convert'; //JSON形式のデータを扱う
import 'package:path_provider/path_provider.dart';
import 'dart:io';

//関連付けの線を描画する
void relationLinePaint(Canvas canvas,CanvasZone widget) {
  final paint = Paint()
    ..color = Colors.blue
    ..strokeWidth = 2;

  if (widget.key.currentState == null) return;
  if (widget.key.currentState!.lanes.isEmpty) return;
  if (widget.key.currentState!.lanes[0].ideas.isEmpty) return;
  if (widget.key.currentState!.lanes[0].key.currentContext == null) return;

  if (widget.key.currentState!.relatedIdeasList.isNotEmpty) {
    for (var relationSet in widget.key.currentState!.relatedIdeasList) {
      Idea origin = relationSet.origin;
      Idea related = relationSet.related;
      print("[relationLinePaint] origin lane:${origin.parentLane?.index},idea:${origin.index} , related lane:${related.parentLane?.index},idea:${related.index}");

      RenderBox lane0Box = widget.key.currentState!.lanes[0].key.currentContext?.findRenderObject() as RenderBox;
      RenderBox originIdeaBox = origin.key.currentContext?.findRenderObject() as RenderBox;
      RenderBox originIdeaTextFieldBox = origin.textFieldKey.currentContext?.findRenderObject() as RenderBox;
      RenderBox relatedIdeaBox = related.key.currentContext?.findRenderObject() as RenderBox;
      RenderBox relatedIdeaTextFieldBox = related.textFieldKey.currentContext?.findRenderObject() as RenderBox;

      double originIdeaY = originIdeaBox.localToGlobal(Offset.zero).dy - lane0Box.localToGlobal(Offset.zero).dy + (originIdeaBox.size.height / 2 );
      double originTextFieldX = originIdeaTextFieldBox.localToGlobal(Offset.zero).dx;
      if (origin.parentLane!.index < related.parentLane!.index) { //Originが左側なら、Originの右側を起点とする
        originTextFieldX += originIdeaTextFieldBox.size.width;
      }

      canvas.drawCircle(Offset(originTextFieldX, originIdeaY) , 3, paint);

      double relatedIdeaY = relatedIdeaBox.localToGlobal(Offset.zero).dy - lane0Box.localToGlobal(Offset.zero).dy + (relatedIdeaBox.size.height / 2 );
      double relatedTextFieldX = relatedIdeaTextFieldBox.localToGlobal(Offset.zero).dx;
      if (origin.parentLane!.index > related.parentLane!.index) { //Originが右側なら、Relatedの右側を起点とする
        relatedTextFieldX += relatedIdeaTextFieldBox.size.width;
      }
      if (origin.parentLane!.index < related.parentLane!.index && related.indentLevel >= 1) { //Relatedが右側にあり、インデントされている場合
        relatedIdeaY += 5; //Related側のインデントの線と重なるのを避けるために少しずらす
      }

      canvas.drawCircle(Offset(relatedTextFieldX, relatedIdeaY) , 3, paint);
      canvas.drawLine(Offset(originTextFieldX, originIdeaY), Offset(relatedTextFieldX, relatedIdeaY), paint);

    }
  }
}

void relationLinePaintForDebug(Canvas canvas, CanvasZone widget) {
  //ツールバーの下：Offset(0,0) 又は canvasZone..RenderObject()のTop
  //lanes[0]..RenderObject().localToGlobalのTopは、なぜかIdeasのTopの位置あたりになってしまう（タイトルより下）
  //lanes[0].ideas[0]..RenderObject().localToGlobalのTopは、中途半端に２つめのIdeasのTopのあたりになってしまう
  //とりあえずtitle分下にずらし、idea[0]のTopの位置を求めるには下記で行けそう、
  //allIdeaTopY = idea0box.localToGlobal(Offset.zero).dy - lane0box.localToGlobal(Offset.zero).dy;

  final paint = Paint()
    ..color = Colors.black;
  canvas.drawCircle(const Offset(10,0), 5, paint);

  paint.color = Colors.purple;
  canvas.drawCircle( (widget.key.currentContext?.findRenderObject() as RenderBox).localToGlobal(Offset.zero), 5, paint);

  if (widget.key.currentState == null) return;
  if (widget.key.currentState!.lanes.isEmpty) return;
  if (widget.key.currentState!.lanes[0].ideas.isEmpty) return;

  RenderBox lane0Box = widget.key.currentState!.lanes[0].key.currentContext?.findRenderObject() as RenderBox;
  RenderBox idea0Box = widget.key.currentState!.lanes[0].ideas[0].key.currentContext?.findRenderObject() as RenderBox;
  RenderBox idea0TextFieldBox = widget.key.currentState!.lanes[0].ideas[0].textFieldKey.currentContext?.findRenderObject() as RenderBox;

  paint.color = Colors.red;
  canvas.drawCircle(lane0Box.localToGlobal(Offset.zero), 5, paint);

  paint.color = Colors.green;
  canvas.drawCircle(idea0Box.localToGlobal(Offset.zero), 10, paint);

  double allIdeaTopY = idea0Box.localToGlobal(Offset.zero).dy - lane0Box.localToGlobal(Offset.zero).dy;
  double textFieldLeftX = idea0TextFieldBox.localToGlobal(Offset.zero).dx;
  paint.color = Colors.yellow;
  canvas.drawCircle(Offset(textFieldLeftX + idea0TextFieldBox.size.width, allIdeaTopY + (idea0Box.size.height / 2 )) , 5, paint);
}

void indentLinePaint(Canvas canvas,Size size,BuildContext context, int index, int indentLevel, double textFieldHeight, double boxSpacing, double indentWidth) {
  // インデントの線を描画する
  final paint = Paint()
    ..color = Colors.grey
    ..strokeWidth = 1;
  var leftX = indentWidth / 2;

  // 一行上のIdeaのindentLevelを取得する
  int upperIndentLevel = 0;
  int upperIndex = index - 1;

  //描画：Canvasの起点は左側センター
  if (indentLevel > 0 && index > 0 /*一番上の時はツリーを描画しない*/) {
    //一番上の親が居ない場合の特別対応：自分の上のどこかに、indentLevelが小さい親がいるかチェック
    bool cancelFlg = false; //描画しない特別な場合用
    var i = index - 1;
    while (i >= 0) {
      if ((LaneInheritedWidget.of(context)
          .ideas[i].indentLevel) <
          indentLevel) {
        break;
      }
      i--;
    }
    if (i == -1) cancelFlg = true;

    if (!cancelFlg) {
      //縦の線：左側の基準
      leftX = leftX + (indentWidth * (indentLevel - 1));

      //縦の線：自分の領域内で上に引く
      double startY =
          0 - (textFieldHeight / 2) - (boxSpacing * 2);

      //縦の線：自分の領域外でどのくらい上まで引くかを計算
      upperIndentLevel = LaneInheritedWidget.of(context)
          .ideas[upperIndex].indentLevel;
      if (indentLevel <= upperIndentLevel) {
        while (indentLevel < upperIndentLevel && upperIndex >= 0) {
          startY -= (textFieldHeight + boxSpacing * 2);
          upperIndex--;
          upperIndentLevel = LaneInheritedWidget.of(context)
              .ideas[upperIndex].indentLevel;
        }
        if (indentLevel <= upperIndentLevel) {
          startY -= textFieldHeight / 2;
        }
      }

      //縦の線
      canvas.drawLine(Offset(leftX, 0), Offset(leftX, startY), paint);

      //横の線
      canvas.drawLine(Offset(leftX, size.height),
          Offset(indentWidth * indentLevel, size.height), paint);
    }
  }
}

void findAndRepaintAffectedIdeas(BuildContext context, int myIndex, int myIndentLevel, int startIndex, int endIndex){
  // Find the start index
  for (int i = myIndex - 1; i >= 0; i--) {
    if (LaneInheritedWidget.of(context)
        .ideas[i].indentLevel == myIndentLevel - 1) {
      startIndex = i;
      break;
    }
  }
  // Find the end index
  for (int i = myIndex + 1;
  i < LaneInheritedWidget.of(context).ideas.length;
  i++) {
    if ((LaneInheritedWidget.of(context)
        .ideas[i].indentLevel) >= myIndentLevel) {
      endIndex = i;
      break;
    }
  }
  LaneInheritedWidget.of(context).redrawAffectedIdeas(startIndex, endIndex);
}

Future<String> get _defaultFileName async {
  final directory = await getApplicationDocumentsDirectory();
  return '${directory.path}/default.json';
}

Future<void> saveData({String? fileName, required CanvasZone? widget}) async {
  List<Map<String, dynamic>> lanesJson = [];

  fileName ??= await _defaultFileName;

  if(widget == null) return;
  if(widget.key.currentState == null) return;

  for (var lane in widget.key.currentState!.lanes ) {
    List<Map<String, dynamic>> ideasJson = [];
    for (var idea in lane.ideas) {
      ideasJson.add({
        'index': idea.index,
        'indentLevel': idea.indentLevel,
        'content': idea.key.currentState?.textController.text ?? '',
      });
    }
    lanesJson.add({
      'key': lane.key.toString(),
      'index': lane.index,
      'title': lane.key.currentState?.titleController.text ?? '',
      'ideas': ideasJson,
    });
  }

  List<Map<String, dynamic>> relatedIdeasJson = [];
  widget.key.currentState!.relatedIdeasList.forEach((relationSet) {
    relatedIdeasJson.add({
      'origin_lane_index': relationSet.origin.parentLane?.index,
      'origin_idea_key': relationSet.origin.key.toString(),
      'origin_idea_index': relationSet.origin.index,
      'related_lane_index': relationSet.related.parentLane?.index,
      'related_idea_key': relationSet.related.key.toString(),
      'related_idea_index': relationSet.related.index,
    });
  });

  String jsonString = jsonEncode({'lanes': lanesJson, 'relatedIdeas': relatedIdeasJson});
  await File(fileName).writeAsString(jsonString);
}

Future<void> loadData({String? fileName, required CanvasZone? widget}) async {
  fileName ??= await _defaultFileName;
  final file = File(fileName);
  if (await file.exists() == false) {
    print('No such files:{$fileName}');
    return;
  }
  String jsonString = await file.readAsString();
  Map<String, dynamic> jsonMap = jsonDecode(jsonString);

  if(widget == null) return;
  if(widget.key.currentState == null) return;

  List<Lane> loadedLanes = [];
  for (var laneJson in jsonMap['lanes']) {
    List<Idea> loadedIdeas = [];

    var newLane = Lane(
      index: laneJson['index'] ?? 0,
      title: laneJson['title'] ?? '',
      ideas: loadedIdeas,
    );
    for (var ideaJson in laneJson['ideas']) {
      loadedIdeas.add(Idea(
        index: ideaJson['index'],
        indentLevel: ideaJson['indentLevel'],
        parentLane: newLane,
      ));
    }
    loadedLanes.add(newLane);
  }
  for (int i = 0; i < loadedLanes.length; i++) {
    for (int j = 0; j < loadedLanes[i].ideas.length; j++) {
      loadedLanes[i].ideas[j].content = jsonMap['lanes'][i]['ideas'][j]['content'];
    }
  }
  widget.key.currentState!.lanes = loadedLanes;

  widget.key.currentState!.relatedIdeasList.clear();
  if (jsonMap['relatedIdeas'] != null) {
    for (var relatedJson in jsonMap['relatedIdeas']) {
      var originLaneIndex = relatedJson['origin_lane_index'];
      var originIdeaIndex = relatedJson['origin_idea_index'];
      var relatedLaneIndex = relatedJson['related_lane_index'];
      var relatedIdeaIndex = relatedJson['related_idea_index'];
      IdeasRelation relationSet = IdeasRelation(
          origin: loadedLanes[originLaneIndex].ideas[originIdeaIndex], related: loadedLanes[relatedLaneIndex].ideas[relatedIdeaIndex]);
      widget.key.currentState!.relatedIdeasList.add(relationSet);
      print("[loadData] origin lane:$originLaneIndex,idea:$originIdeaIndex, related lane:$relatedLaneIndex,idea:$relatedIdeaIndex");
      loadedLanes[originLaneIndex].ideas[originIdeaIndex].relatedIdeas.add(loadedLanes[relatedLaneIndex].ideas[relatedIdeaIndex]);
    }
  }
}