import 'dart:convert' show base64Decode;

import 'package:flutter/material.dart';
import 'package:fotodocumentation/dto/customer_dto.dart';
import 'package:fotodocumentation/dto/picture_dto.dart';
import 'package:fotodocumentation/pages/customer/customer_back_button.dart';
import 'package:fotodocumentation/pages/customer/picture_fullscreen_dialog.dart';
import 'package:fotodocumentation/pages/ui_utils/component/page_header_widget.dart';
import 'package:fotodocumentation/pages/ui_utils/general_style.dart';
import 'package:fotodocumentation/utils/di_container.dart';
import 'package:fotodocumentation/utils/global_router.dart';
import 'package:intl/intl.dart';

class PictureWidgetHolder {
  final CustomerDto customerDto;
  final PictureDto pictureDto;

  const PictureWidgetHolder(this.customerDto, this.pictureDto);
}

class PictureWidget extends StatefulWidget {
  final CustomerDto customerDto;
  final PictureDto pictureDto;
  const PictureWidget({super.key, required this.customerDto, required this.pictureDto});

  @override
  State<PictureWidget> createState() => _PictureWidgetState();
}

class _PictureWidgetState extends State<PictureWidget> {
  GeneralStyle get _generalStyle => DiContainer.get();

  late PictureDto _selectedPicture;
  late DateFormat _dateFormat;
  final ScrollController _commentScrollController = ScrollController();

  @override
  void initState() {
    super.initState();
    _dateFormat = DateFormat('dd.MM.yyyy, hh:mm');
    _selectedPicture = widget.pictureDto;
  }

  @override
  void dispose() {
    _commentScrollController.dispose();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: Container(
        color: _generalStyle.pageBackgroundColor,
        child: Padding(
          padding: const EdgeInsets.only(top: 8.0, left: 50.0, right: 50.0, bottom: 8.0),
          child: _body(context),
        ),
      ),
    );
  }

  Widget _body(BuildContext context) {
    final pictures = widget.customerDto.pictures;
    return Column(
      mainAxisAlignment: MainAxisAlignment.start,
      crossAxisAlignment: CrossAxisAlignment.start,
      children: [
        PageHeaderWidget(text: widget.customerDto.name),
        CustomerBackButton(path: GlobalRouter.pathCustomer),
        const SizedBox(height: 24),
        Expanded(
          child: _mainWidget(context),
        ),
        _bottomNavigationWidget(pictures),
      ],
    );
  }

  Widget _mainWidget(BuildContext context) {
    return LayoutBuilder(
      builder: (context, constraints) {
        final isNarrow = constraints.maxWidth < 800;
        return SingleChildScrollView(
          child: isNarrow
              ? Column(
                  mainAxisAlignment: MainAxisAlignment.start,
                  crossAxisAlignment: CrossAxisAlignment.start,
                  children: [
                    _imageWidget(_selectedPicture),
                    const SizedBox(height: 32),
                    _contentWidget(_selectedPicture),
                  ],
                )
              : Row(
                  mainAxisAlignment: MainAxisAlignment.start,
                  crossAxisAlignment: CrossAxisAlignment.start,
                  children: [
                    _imageWidget(_selectedPicture),
                    const SizedBox(width: 32),
                    Expanded(child: _contentWidget(_selectedPicture)),
                  ],
                ),
        );
      },
    );
  }

  Widget _imageWidget(PictureDto dto) {
    return GestureDetector(
      key: const Key("image"),
      behavior: HitTestBehavior.opaque,
      onTap: () => _showFullscreenImage(dto),
      child: MouseRegion(
        cursor: SystemMouseCursors.click,
        child: ConstrainedBox(
          constraints: const BoxConstraints(minWidth: 100, minHeight: 100),
          child: Image.memory(
            base64Decode(dto.image),
            fit: BoxFit.contain,
          ),
        ),
      ),
    );
  }

  void _showFullscreenImage(PictureDto dto) {
    showDialog(
      context: context,
      builder: (BuildContext context) {
        return PictureFullscreenDialog(dto: dto);
      },
    );
  }

  Widget _contentWidget(PictureDto dto) {
    final labelStyle = TextStyle(
      fontWeight: FontWeight.normal,
      fontSize: 16,
      fontFamily: _generalStyle.fontFamily,
      color: _generalStyle.primaryTextLabelColor,
    );

    final contentStyle = TextStyle(
      fontWeight: FontWeight.bold,
      fontSize: 16,
      fontFamily: _generalStyle.fontFamily,
      color: _generalStyle.secondaryTextLabelColor,
    );

    return Column(crossAxisAlignment: CrossAxisAlignment.start, children: [
      Text(
        _dateFormat.format(dto.pictureDate),
        style: TextStyle(
          fontWeight: FontWeight.bold,
          fontSize: 44,
          fontFamily: _generalStyle.fontFamily,
          color: _generalStyle.primaryTextLabelColor,
        ),
      ),
      
      Padding(
        padding: const EdgeInsets.only(top: 20.0),
        child: Text(
          "KUNDENNUMMER",
          style: labelStyle,
        ),
      ),
      Padding(
        padding: const EdgeInsets.only(top: 4.0),
        child: Text(
          widget.customerDto.customerNumber,
          style: contentStyle,
        ),
      ),
      Padding(
        padding: const EdgeInsets.only(top: 20.0),
        child: Text(
          "KOMMENTAR",
          style: labelStyle,
        ),
      ),
      Padding(
        padding: const EdgeInsets.only(top: 4.0),
        child: SizedBox(
          width: double.infinity,
          height: 150,
          child: Scrollbar(
            controller: _commentScrollController,
            thumbVisibility: true,
            child: SingleChildScrollView(
              controller: _commentScrollController,
              padding: const EdgeInsets.all(8.0),
              child: Text(
                dto.comment ?? "",
                style: contentStyle,
              ),
            ),
          ),
        ),
      ),
    ]);
  }

  // Bottom navigation buttons
  Widget _bottomNavigationWidget(List<PictureDto> pictures) {
    final currentIndex = pictures.indexWhere((p) => p.id == _selectedPicture.id);
    final hasPrevious = currentIndex > 0;
    final hasNext = currentIndex < pictures.length - 1;

    return Padding(
      padding: const EdgeInsets.only(bottom: 24.0),
      child: Row(
        mainAxisAlignment: MainAxisAlignment.center,
        children: [
          // Previous button
          IconButton(
            onPressed: hasPrevious ? () => _actionNavigateToPicture(currentIndex - 1) : null,
            icon: Icon(Icons.chevron_left, color: _generalStyle.nextTextColor, size: 32),
          ),
          const SizedBox(width: 24),
          // Picture counter text
          Row(
            mainAxisSize: MainAxisSize.min,
            children: [
              Container(
                padding: const EdgeInsets.symmetric(horizontal: 12, vertical: 6),
                decoration: BoxDecoration(
                  color: Colors.white,
                  borderRadius: BorderRadius.circular(8),
                ),
                child: Text(
                  '${currentIndex + 1}',
                  style: TextStyle(
                    fontFamily: _generalStyle.fontFamily,
                    fontSize: 16,
                    fontWeight: FontWeight.bold,
                    color: _generalStyle.nextTextColor,
                  ),
                ),
              ),
              const SizedBox(width: 8),
              Text(
                'von ${pictures.length}',
                style: TextStyle(
                  fontFamily: _generalStyle.fontFamily,
                  fontSize: 16,
                  fontWeight: FontWeight.normal,
                  color: _generalStyle.nextTextColor,
                ),
              ),
            ],
          ),
          const SizedBox(width: 24),
          // Next button
          IconButton(
            onPressed: hasNext ? () => _actionNavigateToPicture(currentIndex + 1) : null,
            icon: Icon(Icons.chevron_right, color: _generalStyle.nextTextColor, size: 32),
          ),
        ],
      ),
    );
  }

  void _actionNavigateToPicture(int index) {
    final pictures = widget.customerDto.pictures;
    if (index >= 0 && index < pictures.length) {
      setState(() {
        _selectedPicture = pictures[index];
      });
    }
  }
}