import 'package:flutter/material.dart';
import 'package:go_router/go_router.dart';
import 'package:result_monad/result_monad.dart';

import '../controls/login_aware_cached_network_image.dart';
import '../controls/padding.dart';
import '../controls/responsive_max_width.dart';
import '../controls/standard_appbar.dart';
import '../globals.dart';
import '../models/exec_error.dart';
import '../models/image_entry.dart';
import '../models/visibility.dart';
import '../services/gallery_service.dart';
import '../utils/active_profile_selector.dart';
import '../utils/snackbar_builder.dart';

class ImageEditorScreen extends StatefulWidget {
  final String galleryName;
  final String imageId;

  const ImageEditorScreen({
    super.key,
    required this.galleryName,
    required this.imageId,
  });

  @override
  State<ImageEditorScreen> createState() => _ImageEditorScreenState();
}

class _ImageEditorScreenState extends State<ImageEditorScreen> {
  late final Result<ImageEntry, ExecError> originalImageResult;
  final altTextController = TextEditingController();

  @override
  void initState() {
    super.initState();
    originalImageResult = getIt<ActiveProfileSelector<GalleryService>>()
        .activeEntry
        .andThen((gs) => gs.getImage(widget.galleryName, widget.imageId))
        .withResult((image) {
      altTextController.text = image.description;
    }).execErrorCast();
  }

  bool get changed => originalImageResult
      .transform((image) => image.description != altTextController.text)
      .getValueOrElse(() => false);

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: StandardAppBar.build(
        context,
        'Edit Image',
        withDrawer: true,
      ),
      body: SingleChildScrollView(
        child: ResponsiveMaxWidth(
          child: Padding(
            padding: const EdgeInsets.all(8.0),
            child: Column(
              children: [
                ...originalImageResult.fold(
                  onSuccess: (image) => buildEditor(image),
                  onError: (error) => buildError(error),
                ),
                const VerticalPadding(),
                Row(
                  mainAxisAlignment: MainAxisAlignment.center,
                  children: [
                    ElevatedButton(
                        onPressed: () async {
                          if (!changed) {
                            return;
                          }
                          final result = await getIt<
                                  ActiveProfileSelector<GalleryService>>()
                              .activeEntry
                              .andThenAsync(
                                (gs) async => await gs
                                    .updateImage(originalImageResult.value.copy(
                                  description: altTextController.text,
                                )),
                              );

                          if (!mounted) {
                            return;
                          }

                          result.match(
                            onSuccess: (_) => context.pop(),
                            onError: (error) => buildSnackbar(context,
                                'Error attempting to update image: $error'),
                          );
                        },
                        child: const Text('Save')),
                    const HorizontalPadding(),
                    ElevatedButton(
                        onPressed: () async {
                          if (!changed) {
                            context.pop();
                          }

                          final ok = await showYesNoDialog(
                            context,
                            'Cancel changes?',
                          );
                          if (ok == true && mounted) {
                            context.pop();
                          }
                        },
                        child: const Text('Cancel')),
                  ],
                )
              ],
            ),
          ),
        ),
      ),
    );
  }

  List<Widget> buildEditor(ImageEntry originalImage) {
    return [
      Row(
        children: [
          const Text('Visibility:'),
          const HorizontalPadding(),
          originalImage.visibility.type == VisibilityType.public
              ? const Icon(Icons.public)
              : const Icon(Icons.lock),
        ],
      ),
      const VerticalPadding(),
      LoginAwareCachedNetworkImage(imageUrl: originalImage.thumbnailUrl),
      const VerticalPadding(),
      TextField(
        controller: altTextController,
        maxLines: 10,
        decoration: InputDecoration(
          labelText: 'ALT Text',
          alignLabelWithHint: true,
          border: OutlineInputBorder(
            borderSide: const BorderSide(),
            borderRadius: BorderRadius.circular(5.0),
          ),
        ),
      ),
    ];
  }

  List<Widget> buildError(ExecError error) {
    return [Text('Error loading image: $error')];
  }
}