import 'dart:async';

import 'package:flutter/cupertino.dart';
import 'package:flutter/material.dart';
import 'package:flutter_pdfview/flutter_pdfview.dart';

class PDFScreen extends StatefulWidget {
  final String path;
  final int inlet;

  PDFScreen({Key key, this.path, this.inlet}) : super(key: key);

  _PDFScreenState createState() => _PDFScreenState();
}

class _PDFScreenState extends State<PDFScreen> with WidgetsBindingObserver {
  final Completer<PDFViewController> _controller =
      Completer<PDFViewController>();
  int pages = 0;
  int currentPage = 0;
  int pageTotal = 0;
  bool isReady = false;
  String errorMessage = '';

  @override
  Widget build(BuildContext context) {
    return widget.inlet == 1
        ? Material(
            type: MaterialType.transparency,
            child: Stack(
              children: <Widget>[
                Center(
                  child: Container(
                    height: 250,
                    decoration: BoxDecoration(
                      color: Colors.white,
                    ),
                    child: PDFView(
                      filePath: widget.path,
                      enableSwipe: true,
                      swipeHorizontal: true,
                      autoSpacing: false,
                      pageFling: true,
                      pageSnap: true,
                      defaultPage: currentPage,
                      fitPolicy: FitPolicy.BOTH,
                      preventLinkNavigation: false,
                      // if set to true the link is handled in flutter
                      onRender: (_pages) {
                        setState(() {
                          pages = _pages;
                          isReady = true;
                        });
                      },
                      onError: (error) {
                        setState(() {
                          errorMessage = error.toString();
                        });
                        print(error.toString());
                      },
                      onPageError: (page, error) {
                        setState(() {
                          errorMessage = '$page: ${error.toString()}';
                        });
                        print('$page: ${error.toString()}');
                      },
                      onViewCreated: (PDFViewController pdfViewController) {
                        _controller.complete(pdfViewController);
                      },
                      onLinkHandler: (String uri) {
                        print('goto uri: $uri');
                      },
                      onPageChanged: (int page, int total) {
                        if (total > 0) {
                          print('page change: $page/$total');
                          setState(() {
                            currentPage = page;
                            pageTotal = total;
                          });
                        } else {
                          pageTotal = 1;
                        }
                      },
                    ),
                  ),
                ),
                errorMessage.isEmpty
                    ? !isReady
                        ? Center(
                            child: CircularProgressIndicator(),
                          )
                        : Container()
                    : Center(
                        child: Text(errorMessage),
                      ),
                //pdfindex显示
                Positioned(
                  width: MediaQuery.of(context).size.width,
                  bottom: 45,
                  child: Center(
                    child: Text("${currentPage + 1}/${(pageTotal > 0)?pageTotal:1}",
                        style: TextStyle(color: Colors.white, fontSize: 16)),
                  ),
                ),
              ],
            ),
          )
        : Scaffold(
            body: Stack(
              children: <Widget>[
                PDFView(
                  filePath: widget.path,
                  enableSwipe: true,
                  swipeHorizontal: true,
                  autoSpacing: false,
                  pageFling: true,
                  pageSnap: true,
                  defaultPage: currentPage,
                  fitPolicy: FitPolicy.BOTH,
                  preventLinkNavigation: false,
                  // if set to true the link is handled in flutter
                  onRender: (_pages) {
                    setState(() {
                      pages = _pages;
                      isReady = true;
                    });
                  },
                  onError: (error) {
                    setState(() {
                      errorMessage = error.toString();
                    });
                    print(error.toString());
                  },
                  onPageError: (page, error) {
                    setState(() {
                      errorMessage = '$page: ${error.toString()}';
                    });
                    print('$page: ${error.toString()}');
                  },
                  onViewCreated: (PDFViewController pdfViewController) {
                    _controller.complete(pdfViewController);
                  },
                  onLinkHandler: (String uri) {
                    print('goto uri: $uri');
                  },
                  onPageChanged: (int page, int total) {
                    if (total > 0) {
                      print('page change: $page/$total');
                      setState(() {
                        currentPage = page;
                        pageTotal = total;
                      });
                    } else {
                      pageTotal = 1;
                    }
                  },
                ),
                errorMessage.isEmpty
                    ? !isReady
                        ? Center(
                            child: CircularProgressIndicator(),
                          )
                        : Container()
                    : Center(
                        child: Text(errorMessage),
                      ),
                //pdfindex显示
                Positioned(
                  bottom: 45,
                  width: MediaQuery.of(context).size.width,
                  child: Center(
                    child: Text("${currentPage + 1}/${(pageTotal > 0)?pageTotal:1}",
                        style: TextStyle(color: Colors.black, fontSize: 16)),
                  ),
                ),
                Positioned(
                  //右上角关闭按钮
                  right: 10,
                  top: MediaQuery.of(context).padding.top,
                  child: IconButton(
                    icon: Icon(
                      Icons.close,
                      size: 30,
                      color: Colors.black,
                    ),
                    onPressed: () {
                      Navigator.of(context).pop();
                    },
                  ),
                ),
              ],
            ),
          );
  }
}