import 'dart:convert';
import 'dart:typed_data';

import 'package:charset_converter/charset_converter.dart';
import 'package:esc_pos_bluetooth/esc_pos_bluetooth.dart';
import 'package:esc_pos_utils/esc_pos_utils.dart';
import 'package:flutter/material.dart' hide Image;
import 'package:image/image.dart' as Im;
import 'package:flutter/services.dart';
import 'package:intl/intl.dart';

class PrinterSelectView extends StatefulWidget {
  PrinterSelectView({Key key, this.title}) : super(key: key);
  final String title;

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

class _PrinterSelectViewState extends State<PrinterSelectView> {
  PrinterBluetoothManager printerManager = PrinterBluetoothManager();
  List<PrinterBluetooth> _devices = [];

  @override
  void initState() {
    super.initState();

    printerManager.scanResults.listen((devices) async {
      // print('UI: Devices found ${devices.length}');
      setState(() {
        _devices = devices;
      });
    });
  }

  void _startScanDevices() {
    setState(() {
      _devices = [];
    });
    printerManager.startScan(Duration(seconds: 4));
  }

  void _stopScanDevices() {
    printerManager.stopScan();
  }

  Future<Ticket> demoReceipt(PaperSize paper) async {
    final Ticket ticket = Ticket(paper, );

    // Print image
    final ByteData data = await rootBundle.load('assets/images/aman_kassa_check.png');
    final Uint8List bytes = data.buffer.asUint8List();
    final Im.Image image = Im.decodeImage(bytes);
    Im.Image thumbnail = Im.copyResize(image, width: 270);
    // ticket.image(thumbnail, align: PosAlign.center);

    //ticket.imageRaster(image, align: PosAlign.center);

    ticket.text('AMAN-SATU',
        styles: PosStyles(
          align: PosAlign.center,
          height: PosTextSize.size2,
          width: PosTextSize.size2,
        ),
        linesAfter: 1);

    ticket.text('889  Watson Lane', styles: PosStyles(align: PosAlign.center));
    ticket.text('Русский язык', styles: PosStyles(align: PosAlign.center, codeTable: PosCodeTable.westEur), containsChinese: true);
    ticket.text('Русский язык', styles: PosStyles(align: PosAlign.center, fontType: PosFontType.fontA), containsChinese: true);
    ticket.text('Русский язык', styles: PosStyles(align: PosAlign.center, fontType: PosFontType.fontB), containsChinese: true);
    ticket.text('Русский язык', styles: PosStyles(align: PosAlign.center, height: PosTextSize.size1), containsChinese: true);
    ticket.text('Русский язык', styles: PosStyles(align: PosAlign.center, width: PosTextSize.size2), containsChinese: true);
    ticket.text('Русский язык', styles: PosStyles(align: PosAlign.center, width: PosTextSize.size3), containsChinese: true);
    ticket.text('Русский язык', styles: PosStyles(align: PosAlign.center, width: PosTextSize.size4), containsChinese: true);
    ticket.text('Tel: 830-221-1234', styles: PosStyles(align: PosAlign.center));
    ticket.text('Web: www.example.com',
        styles: PosStyles(align: PosAlign.center), linesAfter: 1);

    ticket.hr();
    ticket.row([
      PosColumn(text: 'Qty', width: 1),
      PosColumn(text: 'Item', width: 7),
      PosColumn(
          text: 'Price', width: 2, styles: PosStyles(align: PosAlign.right)),
      PosColumn(
          text: 'Total', width: 2, styles: PosStyles(align: PosAlign.right)),
    ]);

    ticket.row([
      PosColumn(text: '2', width: 1),
      PosColumn(text: 'ONION RINGS', width: 7),
      PosColumn(
          text: '0.99', width: 2, styles: PosStyles(align: PosAlign.right)),
      PosColumn(
          text: '1.98', width: 2, styles: PosStyles(align: PosAlign.right)),
    ]);
    ticket.row([
      PosColumn(text: '1', width: 1),
      PosColumn(text: 'PIZZA', width: 7),
      PosColumn(
          text: '3.45', width: 2, styles: PosStyles(align: PosAlign.right)),
      PosColumn(
          text: '3.45', width: 2, styles: PosStyles(align: PosAlign.right)),
    ]);
    ticket.row([
      PosColumn(text: '1', width: 1),
      PosColumn(text: 'SPRING ROLLS', width: 7),
      PosColumn(
          text: '2.99', width: 2, styles: PosStyles(align: PosAlign.right)),
      PosColumn(
          text: '2.99', width: 2, styles: PosStyles(align: PosAlign.right)),
    ]);
    ticket.row([
      PosColumn(text: '3', width: 1),
      PosColumn(text: 'CRUNCHY STICKS', width: 7),
      PosColumn(
          text: '0.85', width: 2, styles: PosStyles(align: PosAlign.right)),
      PosColumn(
          text: '2.55', width: 2, styles: PosStyles(align: PosAlign.right)),
    ]);
    ticket.hr();

    ticket.row([
      PosColumn(
          text: 'TOTAL',
          width: 6,
          styles: PosStyles(
            height: PosTextSize.size2,
            width: PosTextSize.size2,
          )),
      PosColumn(
          text: '\$10.97',
          width: 6,
          styles: PosStyles(
            align: PosAlign.right,
            height: PosTextSize.size2,
            width: PosTextSize.size2,
          )),
    ]);

    ticket.hr(ch: '=', linesAfter: 1);

    ticket.row([
      PosColumn(
          text: 'Cash',
          width: 7,
          styles: PosStyles(align: PosAlign.right, width: PosTextSize.size2)),
      PosColumn(
          text: '\$15.00',
          width: 5,
          styles: PosStyles(align: PosAlign.right, width: PosTextSize.size2)),
    ]);
    ticket.row([
      PosColumn(
          text: 'Change',
          width: 7,
          styles: PosStyles(align: PosAlign.right, width: PosTextSize.size2)),
      PosColumn(
          text: '\$4.03',
          width: 5,
          styles: PosStyles(align: PosAlign.right, width: PosTextSize.size2)),
    ]);

    ticket.feed(2);
    ticket.text('Thank you!',
        styles: PosStyles(align: PosAlign.center, bold: true));

    final now = DateTime.now();
    final formatter = DateFormat('MM/dd/yyyy H:m');
    final String timestamp = formatter.format(now);
    ticket.text(timestamp,
        styles: PosStyles(align: PosAlign.center), linesAfter: 2);

    // Print QR Code from image
    // try {
    //   const String qrData = 'example.com';
    //   const double qrSize = 200;
    //   final uiImg = await QrPainter(
    //     data: qrData,
    //     version: QrVersions.auto,
    //     gapless: false,
    //   ).toImageData(qrSize);
    //   final dir = await getTemporaryDirectory();
    //   final pathName = '${dir.path}/qr_tmp.png';
    //   final qrFile = File(pathName);
    //   final imgFile = await qrFile.writeAsBytes(uiImg.buffer.asUint8List());
    //   final img = decodeImage(imgFile.readAsBytesSync());

    //   ticket.image(img);
    // } catch (e) {
    //   print(e);
    // }

    // Print QR Code using native function
    // ticket.qrcode('example.com');

    ticket.feed(2);
    ticket.cut();
    return ticket;
  }

  Future<Ticket> testTicket(PaperSize paper) async {
    final Ticket ticket = Ticket(paper);
    Uint8List encTxt4 =
    await CharsetConverter.encode("cp866", "Russian: Привет Мир!");
    ticket.textEncoded(encTxt4,
        styles: PosStyles(codeTable: PosCodeTable.pc866_2));

    ticket.text('Kazakh: Сәлем Әлем!',
        styles: PosStyles(codeTable: PosCodeTable.westEur), containsChinese: true);

    // Uint8List encTxt1 =
    // await CharsetConverter.encode("utf-8", "Kazakh: Сәлем Әлем!");
    // ticket.textEncoded(encTxt1,
    //     styles: PosStyles(codeTable: PosCodeTable.pc866_2));
    ticket.text(
        'Regular: aA bB cC dD eE fF gG hH iI jJ kK lL mM nN oO pP qQ rR sS tT uU vV wW xX yY zZ');
    ticket.text('Special 1: àÀ èÈ éÉ ûÛ üÜ çÇ ôÔ',
        styles: PosStyles(codeTable: PosCodeTable.westEur));
    ticket.text('Special 2: blåbærgrød',
        styles: PosStyles(codeTable: PosCodeTable.westEur));

    ticket.text('Bold text', styles: PosStyles(bold: true));
    ticket.text('Reverse text', styles: PosStyles(reverse: true));
    ticket.text('Underlined text',
        styles: PosStyles(underline: true), linesAfter: 1);
    ticket.text('Align left', styles: PosStyles(align: PosAlign.left));
    ticket.text('Align center', styles: PosStyles(align: PosAlign.center));
    ticket.text('Align right',
        styles: PosStyles(align: PosAlign.right), linesAfter: 1);

    ticket.row([
      PosColumn(
        text: 'col3',
        width: 3,
        styles: PosStyles(align: PosAlign.center, underline: true),
      ),
      PosColumn(
        text: 'col6',
        width: 6,
        styles: PosStyles(align: PosAlign.center, underline: true),
      ),
      PosColumn(
        text: 'col3',
        width: 3,
        styles: PosStyles(align: PosAlign.center, underline: true),
      ),
    ]);

    ticket.text('Text size 200%',
        styles: PosStyles(
          height: PosTextSize.size2,
          width: PosTextSize.size2,
        ));

    // Print image
    //final ByteData data = await rootBundle.load('assets/images/logo.png');
    //final Uint8List bytes = data.buffer.asUint8List();
    // Print image using alternative commands
    // ticket.imageRaster(image);
    // ticket.imageRaster(image, imageFn: PosImageFn.graphics);

    // Print barcode
    final List<int> barData = [1, 2, 3, 4, 5, 6, 7, 8, 9, 0, 4];
    ticket.barcode(Barcode.upcA(barData));

    // Print mixed (chinese + latin) text. Only for printers supporting Kanji mode
    ticket.text(
      'hello ! 中文字 # world @ éphémère &',
      styles: PosStyles(codeTable: PosCodeTable.westEur),
      containsChinese: true,
    );

    ticket.text(
      'hello ! Мир # world @ éphémère &',
      styles: PosStyles(codeTable: PosCodeTable.westEur),
      containsChinese: true,
    );

    ticket.feed(2);

    ticket.cut();
    return ticket;
  }

  void _testPrint(PrinterBluetooth printer) async {
    printerManager.selectPrinter(printer);

    // TODO Don't forget to choose printer's paper
    const PaperSize paper = PaperSize.mm58;

    // TEST PRINT
    // final PosPrintResult res =
    // await printerManager.printTicket(await testTicket(paper));

    // DEMO RECEIPT
    final PosPrintResult res =
    await printerManager.printTicket(await testTicket(paper) , queueSleepTimeMs: 50);

  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text(widget.title),
      ),
      body: ListView.builder(
          itemCount: _devices.length,
          itemBuilder: (BuildContext context, int index) {
            return InkWell(
              onTap: () => _testPrint(_devices[index]),
              child: Column(
                children: <Widget>[
                  Container(
                    height: 60,
                    padding: EdgeInsets.only(left: 10),
                    alignment: Alignment.centerLeft,
                    child: Row(
                      children: <Widget>[
                        Icon(Icons.print),
                        SizedBox(width: 10),
                        Expanded(
                          child: Column(
                            crossAxisAlignment: CrossAxisAlignment.start,
                            mainAxisAlignment: MainAxisAlignment.center,
                            children: <Widget>[
                              Text(_devices[index].name ?? ''),
                              Text(_devices[index].address),
                              Text(
                                'Click to print a test receipt',
                                style: TextStyle(color: Colors.grey[700]),
                              ),
                            ],
                          ),
                        )
                      ],
                    ),
                  ),
                  Divider(),
                ],
              ),
            );
          }),
      floatingActionButton: StreamBuilder<bool>(
        stream: printerManager.isScanningStream,
        initialData: false,
        builder: (c, snapshot) {
          if (snapshot.data) {
            return FloatingActionButton(
              child: Icon(Icons.stop),
              onPressed: _stopScanDevices,
              backgroundColor: Colors.red,
            );
          } else {
            return FloatingActionButton(
              child: Icon(Icons.search),
              onPressed: _startScanDevices,
            );
          }
        },
      ),
    );
  }

}