APP_NEW/lib/Class/Screenshot/screenshot.dart

import 'dart:ui' as ui;
import 'dart:typed_data';
import 'package:flutter/material.dart';
import 'package:flutter/rendering.dart';
import 'package:flutter/widgets.dart';
import 'package:flutter_localizations/flutter_localizations.dart';
import 'package:image_gallery_saver/image_gallery_saver.dart';
import 'package:lamiter/Class/Screenshot/screenshot_widget.dart';
import 'package:lamiter/Provider/Diagnosis/Diagnosis_Item/constitution_provider.dart';
import 'package:lamiter/Provider/Diagnosis/Diagnosis_Item/urban_disease_provider.dart';
import 'package:lamiter/Provider/Diagnosis/Diagnosis_Item/posture_issue_provider.dart';
import 'package:lamiter/Provider/Diagnosis/Diagnosis_Item/symptom_provider.dart';
import 'package:lamiter/Provider/Language/language_provider.dart';
import 'package:provider/provider.dart';
import 'package:flutter_gen/gen_l10n/app_localizations.dart';

class Screenshot {
  final List<ScreenshotWidget> children;
  final double width = 2024;

  const Screenshot({
    required this.children,
  });

  Future<void> screenshot(Locale locale) async {
    final pngBytes = await _mergeWidgetsToPng(
      children,
      locale,
      width: width,
      pixelRatio: 1,
    );
    if (pngBytes == null) return;
    await ImageGallerySaver.saveImage(
      pngBytes,
      quality: 60,
    );
  }

  // 合併多個 widget 的 PNG bytes
  Future<Uint8List?> _mergeWidgetsToPng(
    List<Widget> widgets,
    Locale locale, {
    required double width,
    double pixelRatio = 1.0,
  }) async {
    final images = <ui.Image>[];

    // 渲染每個 widget 成為圖片
    for (var widget in widgets) {
      final image = await _widgetToImage(widget, width, locale);
      if (image == null) return null;
      images.add(image);
    }

    // 計算合併後圖像的總高度
    final totalHeight =
        images.fold(0.0, (sum, img) => sum + img.height.toDouble());

    // 創建畫布
    final recorder = ui.PictureRecorder();
    final canvas = Canvas(
      recorder,
      Rect.fromLTWH(0, 0, width * pixelRatio, totalHeight * pixelRatio),
    );

    // 將圖像逐一繪製到畫布
    double currentOffset = 0.0;
    for (var image in images) {
      final src =
          Rect.fromLTWH(0, 0, image.width.toDouble(), image.height.toDouble());
      final dst = Rect.fromLTWH(0, currentOffset * pixelRatio,
          width * pixelRatio, image.height.toDouble() * pixelRatio);
      canvas.drawImageRect(image, src, dst, Paint());
      currentOffset += image.height.toDouble();
    }

    // 將畫布轉為圖像
    final mergedImage = await recorder.endRecording().toImage(
        (width * pixelRatio).toInt(), (totalHeight * pixelRatio).toInt());

    // 將圖像轉為 PNG bytes
    final byteData =
        await mergedImage.toByteData(format: ui.ImageByteFormat.png);
    return byteData?.buffer.asUint8List();
  }

  // 將 widget 轉換為 PNG
  Future<ui.Image?> _widgetToImage(
      Widget widget, double width, Locale locale) async {
    // 創建一個離屏的 RenderRepaintBoundary
    final repaintBoundary = RenderRepaintBoundary();

    // 創建一個 RenderView 並將 RepaintBoundary 作為子節點
    final renderView = RenderView(
      child: RenderPositionedBox(
        alignment: Alignment.center,
        child: repaintBoundary,
      ),
      configuration: ViewConfiguration(
        physicalConstraints: BoxConstraints(maxWidth: width),
        logicalConstraints: BoxConstraints(maxWidth: width),
        devicePixelRatio: 1.0,
      ),
      view: WidgetsBinding.instance.window,
    );

    // 構建 PipelineOwner
    final pipelineOwner = PipelineOwner();
    renderView.attach(pipelineOwner);
    renderView.prepareInitialFrame();
    // pipelineOwner.rootNode = renderView;

    // 構建 BuildOwner
    final buildOwner = BuildOwner(focusManager: FocusManager());
    final constitutionProvider = ConstitutionProvider();
    await constitutionProvider.init();
    final postureIssueProvider = PostureIssueProvider();
    await postureIssueProvider.init();
    final symptomProvider = SymptomProvider();
    await symptomProvider.init();
    final urbanDiseaseProvider = UrbanDiseaseProvider();
    await urbanDiseaseProvider.init();

    final providerWidgetTree = MultiProvider(
      providers: [
        ChangeNotifierProvider(create: (context) => constitutionProvider),
        ChangeNotifierProvider(create: (context) => postureIssueProvider),
        ChangeNotifierProvider(create: (context) => symptomProvider),
        ChangeNotifierProvider(create: (context) => urbanDiseaseProvider),
        ChangeNotifierProvider(create: (context) => LanguageProvider()),
      ],
      child: Localizations(
        delegates: const [
          AppLocalizations.delegate,
          GlobalMaterialLocalizations.delegate,
          GlobalWidgetsLocalizations.delegate,
          GlobalCupertinoLocalizations.delegate,
        ],
        locale: locale,
        child: widget,
      ),
    );

    final renderElement = RenderObjectToWidgetAdapter<RenderBox>(
      container: repaintBoundary,
      child: providerWidgetTree,
    ).attachToRenderTree(buildOwner);

    // 執行布局和繪製
    buildOwner.buildScope(renderElement);
    pipelineOwner.flushLayout();
    pipelineOwner.flushCompositingBits();
    pipelineOwner.flushPaint();

    Size size = renderElement.size ?? Size(1, 1);
    final pixelRatio = width / size.width;

    // 提取圖像
    final image = await repaintBoundary.toImage(pixelRatio: pixelRatio);
    return image;
  }
}