tablet-app/lib/Screens/PDF/pdf_view.dart

import 'dart:async';
import 'dart:convert';
import 'dart:io';
//import 'dart:html';
import 'dart:ui' as ui;

import 'package:flutter/foundation.dart';
import 'package:flutter/material.dart';
import 'package:flutter_pdfview/flutter_pdfview.dart';
import 'package:manager_api/api.dart';
import 'package:path_provider/path_provider.dart';
import 'package:provider/provider.dart';
import 'package:tablet_app/Components/loading_common.dart';
import 'package:tablet_app/Models/tabletContext.dart';
import 'package:tablet_app/Screens/PDF/pdf_filter.dart';
import 'package:tablet_app/app_context.dart';
import 'package:tablet_app/constants.dart';


class PDFViewWidget extends StatefulWidget {
  final SectionDTO? section;
  PDFViewWidget({this.section});

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

class _PDFViewWidget extends State<PDFViewWidget> {
  PdfDTO pdfDTO = PdfDTO();
  String remotePDFpath = "";
  final Completer<PDFViewController> _controller = Completer<PDFViewController>();
  int? pages = 0;
  int? currentPage = 0;
  bool isReady = false;
  String errorMessage = '';
  late ValueNotifier<PDFFileDTO?> selectedPdf = ValueNotifier<PDFFileDTO?>(pdfDTO.pdfs!.first);
  ValueNotifier<Map<String, int>> currentState = ValueNotifier<Map<String, int>>({'page': 0, 'total': 1});

  @override
  void initState() {
    print(widget.section!.data);
    pdfDTO = PdfDTO.fromJson(jsonDecode(widget.section!.data!))!;
    print(pdfDTO);
    super.initState();

    /*createFileOfPdfUrl(pdfDTO.source_!).then((f) {
      setState(() {
        remotePDFpath = f.path;
        print("paaath");
        print(remotePDFpath);
      });
    });*/
  }

  Future<File?> createFileOfPdfUrl(TabletAppContext tabletAppContext, PDFFileDTO pdfFileDTO) async {
    Completer<File?> completer = Completer();

    if(pdfFileDTO.pdfFilesAndTitles!.firstWhere((pfat) => pfat.language == tabletAppContext.language).resourceId == null) {
      completer.complete(null);
    } else {
      var file = await _checkIfLocalResourceExists(tabletAppContext, pdfFileDTO.pdfFilesAndTitles!.firstWhere((pfat) => pfat.language == tabletAppContext.language).resourceId!);

      if(file == null) {
        print("Start download file from internet!");
        try {
          // "https://berlin2017.droidcon.cod.newthinking.net/sites/global.droidcon.cod.newthinking.net/files/media/documents/Flutter%20-%2060FPS%20UI%20of%20the%20future%20%20-%20DroidconDE%2017.pdf";
          // final url = "https://pdfkit.org/docs/guide.pdf";
          final url = pdfFileDTO.pdfFilesAndTitles!.firstWhere((pfat) => pfat.language == tabletAppContext.language).resourceUrl!;
          final filename = url.substring(url.lastIndexOf("/") + 1);
          var request = await HttpClient().getUrl(Uri.parse(url));
          var response = await request.close();
          var bytes = await consolidateHttpClientResponseBytes(response);
          var dir = await getApplicationDocumentsDirectory();
          print("Download files");
          print("${dir.path}/$filename");
          File file = File("${dir.path}/$filename");

          await file.writeAsBytes(bytes, flush: true);
          completer.complete(file);
        } catch (e) {
          throw Exception('Error parsing asset file!');
        }
      } else {
        print("FOUND FILE PDF");
        completer.complete(file);
      }
    }

    return completer.future;
  }

  @override
  void dispose() {
    //_webView = null;
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    final appContext = Provider.of<AppContext>(context);
    TabletAppContext tabletAppContext = appContext.getContext();

    var primaryColor = tabletAppContext.configuration != null ? tabletAppContext.configuration!.primaryColor != null ? new Color(int.parse(tabletAppContext.configuration!.primaryColor!.split('(0x')[1].split(')')[0], radix: 16)) : kTestSecondColor : kTestSecondColor;

    pdfDTO.pdfs!.sort((a, b) => a.order!.compareTo(b.order!));

    return pdfDTO.pdfs != null && pdfDTO.pdfs!.length > 0 ?
      Center(
        child: Row(
          mainAxisAlignment: MainAxisAlignment.spaceBetween,
          children: [
            Expanded(
              flex: 1,
              child: Container(
                decoration: BoxDecoration(
                  color: kBackgroundColor,
                  borderRadius: BorderRadius.all(Radius.circular(tabletAppContext.configuration!.roundedValue?.toDouble() ?? 20.0)),
                ),
                child: Padding(
                  padding: const EdgeInsets.all(8.0),
                  child: PdfFilter(
                      pdfsList: pdfDTO.pdfs!,
                      onPDFSelected: (selectedOrder) {
                        selectedPdf.value = pdfDTO.pdfs!.firstWhere((pdf) => pdf.order == selectedOrder);
                      }),
                ),
              ),
            ),
            Expanded(
              flex: 4,
              child: Padding(
                padding: const EdgeInsets.all(8.0),
                child: ValueListenableBuilder<PDFFileDTO?>(
                  valueListenable: selectedPdf,
                  builder: (context, value, _) {
                    return FutureBuilder(
                      future: createFileOfPdfUrl(tabletAppContext, value!),
                      builder: (context, AsyncSnapshot<dynamic> snapshot) {
                        print("snapshot.data");
                        print(snapshot.data);
                        if (snapshot.connectionState == ConnectionState.done) {
                          if(snapshot.data == null) {
                            return Center(child: Text("Aucun fichier à afficher"));
                          } else {
                            return Stack(
                              children: [
                                PDFView(
                                  filePath: snapshot.data.path,
                                  enableSwipe: true,
                                  swipeHorizontal: true,
                                  autoSpacing: true,
                                  pageFling: true,
                                  fitPolicy: FitPolicy.HEIGHT,
                                  onRender: (_pages) {
                                    //setState(() {
                                    pages = _pages;
                                    isReady = true;
                                    //});
                                  },
                                  onError: (error) {
                                    print(error.toString());
                                  },
                                  onPageError: (page, error) {
                                    print('$page: ${error.toString()}');
                                  },
                                  onViewCreated: (PDFViewController pdfViewController) {
                                    //_controller.complete(pdfViewController);
                                  },
                                  onPageChanged: (int? page, int? total) {
                                    currentPage = page;
                                    pages = total;
                                    currentState.value = {'page': page!, 'total': total!};

                                    print('page change: $page/$total');
                                  },
                                ),
                                Positioned(
                                  bottom: 20,
                                  left: 20,
                                  child: ValueListenableBuilder<Map<String, int>>(
                                    valueListenable: currentState,
                                    builder: (context, value, _) {
                                      return Container(
                                        decoration: BoxDecoration(
                                            borderRadius: BorderRadius.all(Radius.circular(tabletAppContext.configuration!.roundedValue?.toDouble() ?? 20.0)),
                                            color: primaryColor
                                          ),
                                          child: Padding(
                                            padding: const EdgeInsets.all(6.0),
                                            child: Text("${value["page"]!+1}/${value["total"]!}",
                                                style: TextStyle(color: Colors.white, fontSize: 20)),
                                          )
                                      );
                                    },
                                  ),
                                ),
                              ],
                            );
                          }
                        } else {
                          return Center(
                              child: Container(
                                  child: LoadingCommon()
                              )
                          );
                        }
                      }
                    );
                  }
                ),
              ),
            ),
          ],
        ),
      ) :
      Center(child: Text("Aucun pdf à afficher", style: TextStyle(fontSize: kNoneInfoOrIncorrect)));
  }
} //_webView

Future<File?> _checkIfLocalResourceExists(TabletAppContext tabletAppContext, String resourceId) async {
  try {
    Directory? appDocumentsDirectory = Platform.isIOS ? await getApplicationDocumentsDirectory() : await getDownloadsDirectory();
    String localPath = appDocumentsDirectory!.path;
    Directory configurationDirectory = Directory('$localPath/${tabletAppContext.configuration!.id}');
    List<FileSystemEntity> fileList = configurationDirectory.listSync();

    if(fileList.any((fileL) => fileL.uri.pathSegments.last.contains(resourceId))) {
      File file = File(fileList.firstWhere((fileL) => fileL.uri.pathSegments.last.contains(resourceId)).path);
      return file;
    }
  } catch (e) {
    print("ERROR _checkIfLocalResourceExists PDF");
    print(e);
  }

  return null;
}