import 'dart:io';

import 'package:cached_network_image/cached_network_image.dart';
import 'package:carousel_slider/carousel_slider.dart';
import 'package:file_picker/file_picker.dart';
import 'package:flutter/material.dart';
import 'package:flutter_file_dialog/flutter_file_dialog.dart';
import 'package:path/path.dart' as p;
import 'package:path_provider/path_provider.dart';
import 'package:relatica/utils/clipboard_utils.dart';

import '../friendica_client/friendica_client.dart';
import '../globals.dart';
import '../models/media_attachment.dart';
import '../services/auth_service.dart';
import '../utils/snackbar_builder.dart';

class ImageViewerScreen extends StatefulWidget {
  final List<MediaAttachment> attachments;
  final int initialIndex;

  const ImageViewerScreen({
    super.key,
    required this.attachments,
    this.initialIndex = 0,
  });

  @override
  State<ImageViewerScreen> createState() => _ImageViewerScreenState();
}

class _ImageViewerScreenState extends State<ImageViewerScreen> {
  MediaAttachment? currentAttachment;

  @override
  void initState() {
    super.initState();
    currentAttachment = widget.attachments[widget.initialIndex];
  }

  Future<void> saveImage(
    BuildContext context,
    MediaAttachment attachment,
  ) async {
    buildSnackbar(context, 'Downloading full image to save locally');
    final appsDir = await getApplicationDocumentsDirectory();
    final filename = p.basename(attachment.fullFileUri.path);
    final bytesResult =
        await RemoteFileClient(getIt<AccountsService>().currentProfile)
            .getFileBytes(attachment.uri);
    if (bytesResult.isFailure && mounted) {
      buildSnackbar(context,
          'Error getting full size version of file: ${bytesResult.error}');
      return;
    }

    if (Platform.isAndroid || Platform.isIOS) {
      final params = SaveFileDialogParams(
        data: bytesResult.value,
        fileName: filename,
      );
      await FlutterFileDialog.saveFile(params: params);
    } else {
      final location = await FilePicker.platform.saveFile(
        dialogTitle: 'Save Image',
        fileName: filename,
        initialDirectory: appsDir.path,
      );
      if (location != null) {
        await File(location).writeAsBytes(bytesResult.value);
      }
    }
  }

  @override
  Widget build(BuildContext context) {
    final width = MediaQuery.of(context).size.width;
    final height = MediaQuery.of(context).size.height;
    final carouselHeight =
        widget.attachments.length == 1 ? height * 0.9 : height * 0.8;
    return Scaffold(
      appBar: AppBar(
        actions: [
          IconButton(
              onPressed: currentAttachment == null
                  ? null
                  : () => saveImage(context, currentAttachment!),
              icon: const Icon(Icons.download))
        ],
      ),
      body: SafeArea(
        child: Column(
          children: [
            CarouselSlider.builder(
              disableGesture: true,
              itemCount: widget.attachments.length,
              itemBuilder: (context, index, realIndex) {
                return SizedBox(
                  width: width,
                  height: carouselHeight,
                  child: InteractiveViewer(
                    maxScale: 10.0,
                    scaleFactor: 400,
                    child: CachedNetworkImage(
                        imageUrl: widget.attachments[index].uri.toString()),
                  ),
                );
              },
              options: CarouselOptions(
                  height: carouselHeight,
                  initialPage: widget.initialIndex,
                  enableInfiniteScroll: false,
                  enlargeCenterPage: true,
                  viewportFraction: 0.95,
                  onPageChanged: (index, reason) {
                    setState(() {
                      currentAttachment = widget.attachments[index];
                    });
                  }),
            ),
            if (currentAttachment != null) buildTextArea(currentAttachment!),
          ],
        ),
      ),
    );
  }

  Widget buildTextArea(MediaAttachment attachment) {
    return Expanded(
      child: Padding(
        padding: const EdgeInsets.all(8.0),
        child: Row(
          mainAxisAlignment: MainAxisAlignment.spaceBetween,
          children: [
            Expanded(
                child: SingleChildScrollView(
              child: Text(attachment.description),
            )),
            IconButton(
              onPressed: () async {
                await copyToClipboard(
                    context: context,
                    text: attachment.description,
                    message: 'Image description copied to clipboard');
              },
              icon: Icon(Icons.copy),
            ),
          ],
        ),
      ),
    );
  }
}