import 'package:fis_measure/interfaces/enums/annotation.dart';
import 'package:fis_measure/interfaces/process/annotations/annotation.dart';
import 'package:fis_measure/interfaces/process/workspace/application.dart';
import 'package:flutter/material.dart';
import 'package:get/get.dart';

import '../positioned_cursor.dart';
import 'arrow_gesture_panel.dart';
import 'input_position_panel.dart';
import 'label_drag_target_pannel.dart';

/// 注释手势层
class AnnotationGestureLayer extends StatefulWidget {
  const AnnotationGestureLayer({Key? key}) : super(key: key);

  @override
  State<AnnotationGestureLayer> createState() => _AnnotationGestureLayerState();
}

class _AnnotationGestureLayerState extends State<AnnotationGestureLayer> {
  late final application = Get.find<IApplication>();

  final mouseState = Get.put<IMouseState>(MouseState());

  IAnnotationItem? currentItem;

  @override
  void initState() {
    currentItem = application.activeAnnotationItem;
    application.activeAnnotationItemChanged.addListener(_onItemChanged);
    super.initState();
  }

  @override
  void dispose() {
    application.activeAnnotationItemChanged.removeListener(_onItemChanged);
    super.dispose();
  }

  void _onItemChanged(Object sender, IAnnotationItem? item) {
    if (!mounted) return;

    if (item?.type != currentItem?.type) {
      setState(() {
        currentItem = item;
      });
    } else {
      currentItem = item;
    }
  }

  @override
  Widget build(BuildContext context) {
    return _buildItemPanel();
    // TODO: melon - optimize with handlers
    return Stack(
      children: [
        _buildItemPanel(),
        _buildTopGesture(),
      ],
    );
  }

  Widget _buildTopGesture() {
    return GestureDetector(
      onPanUpdate: (details) {
        mouseState.mousePosition = details.localPosition;
      },
      child: MouseRegion(
        cursor: SystemMouseCursors.none,
        onHover: (details) {
          mouseState.mousePosition = details.localPosition;
        },
        child: Stack(
          children: const [
            PositionedCursor(),
          ],
        ),
      ),
    );
  }

  Widget _buildItemPanel() {
    if (currentItem == null) {
      return const SizedBox();
    }
    final type = currentItem!.type;
    switch (type) {
      case AnnotationType.label:
        return const AnnotationLabelDragTargetPanel();
      case AnnotationType.input:
        return const AnnotationInputPositionPanel();
      case AnnotationType.arrow:
        return const AnnotationArrowGesturePanel();
    }
  }
}