import 'package:flutter_riverpod/flutter_riverpod.dart';
import 'package:logging/logging.dart';
import 'package:result_monad/result_monad.dart';
import 'package:riverpod_annotation/riverpod_annotation.dart';

import '../models/auth/profile.dart';
import '../models/exec_error.dart';
import '../models/gallery_data.dart';
import '../models/image_entry.dart';
import '../models/networking/paging_data.dart';
import 'networking/friendica_gallery_client_services.dart';
import 'networking/friendica_image_client_services.dart';
import 'rp_provider_extension.dart';

part 'gallery_services.g.dart';

final _galleryLogger = Logger('GalleriesProvider');

@riverpod
class _Galleries extends _$Galleries {
  @override
  Future<Result<Map<String, GalleryData>, ExecError>> build(
    Profile profile,
  ) async {
    _galleryLogger.info('Build for $profile');
    final result = await updateGalleries();
    ref.cacheFor(const Duration(minutes: 30));
    return result;
  }

  Future<Result<Map<String, GalleryData>, ExecError>> updateGalleries() async {
    _galleryLogger.info('Updating galleries for $profile');
    //may need to force update
    final result = await ref.read(galleryDataProvider(profile).future);
    if (result.isFailure) {
      return result.errorCast();
    }

    final galleriesMap = {for (final g in result.value) g.name: g};
    _galleryLogger
        .info(() => 'New gallery data for $profile : ${galleriesMap.values}');
    final rval = Result.ok(galleriesMap).execErrorCast();
    state = AsyncData(rval);
    return rval;
  }
}

final _glLogger = Logger('GalleryListProvider');

@riverpod
class GalleryList extends _$GalleryList {
  @override
  Future<Result<List<GalleryData>, ExecError>> build(Profile profile) async {
    _glLogger.info('Build for $profile');
    final result = await ref
        .watch(_galleriesProvider(profile).future)
        .transform((gm) => gm.values.toList())
        .execErrorCastAsync();
    ref.cacheFor(const Duration(minutes: 30));
    return result;
  }

  Future<Result<Map<String, GalleryData>, ExecError>> updateGalleries() async {
    _galleryLogger.info('Updating galleries for $profile');
    return await ref
        .read(_galleriesProvider(profile).notifier)
        .updateGalleries();
  }
}

@riverpod
class Gallery extends _$Gallery {
  @override
  Future<Result<GalleryData, ExecError>> build(
      Profile profile, String galleryName) async {
    final result = await ref
        .watch(_galleriesProvider(profile).future)
        .andThen<GalleryData, ExecError>((gm) => gm.containsKey(galleryName)
            ? Result.ok(gm[galleryName]!)
            : buildErrorResult(
                type: ErrorType.notFound,
                message: '$galleryName does not exist'))
        .execErrorCastAsync();
    ref.cacheFor(const Duration(minutes: 30));
    return result;
  }

  Future<Result<bool, ExecError>> rename(String newName) async {
    if (newName.isEmpty) {
      return buildErrorResult(
        type: ErrorType.argumentError,
        message: 'Gallery name cannot be empty',
      );
    }

    final result = await ref
        .read(renameGalleryProvider(profile, galleryName, newName).future)
        .withResultAsync(
          (_) async => await ref
              .read(_galleriesProvider(profile).notifier)
              .updateGalleries(),
        )
        .withResult((_) => ref.invalidateSelf());

    return result.execErrorCast();
  }
}

@riverpod
class GalleryImages extends _$GalleryImages {
  static const _imagesPerPage = 50;
  final pages = <PagingData>[];

  @override
  Future<Result<List<ImageEntry>, ExecError>> build(
      Profile profile, String galleryName) async {
    final result = await updateGalleryImages(
      withNextPage: true,
    );
    ref.cacheFor(const Duration(minutes: 30));
    return result;
  }

  FutureResult<List<ImageEntry>, ExecError> updateGalleryImages(
      {required bool withNextPage, bool nextPageOnly = true}) async {
    if (pages.isEmpty) {
      pages.add(PagingData(offset: 0, limit: _imagesPerPage));
    } else if (withNextPage) {
      final offset = pages.last.offset! + _imagesPerPage;
      pages.add(PagingData(offset: offset, limit: _imagesPerPage));
    }

    final imageSet = switch (state) {
      AsyncData(:final value) => value.fold(
          onSuccess: (images) => images.toSet(),
          onError: (_) => <ImageEntry>{}),
      _ => <ImageEntry>{},
    };

    final pagesToUse = nextPageOnly ? [pages.last] : pages;
    for (final page in pagesToUse) {
      final result = await ref
          .read(galleryImagesClientProvider(profile, galleryName, page).future);
      if (result.isFailure) {
        return result.errorCast();
      } else {
        imageSet.addAll(result.value);
      }
    }

    final result = Result.ok(imageSet.toList()).execErrorCast();
    state = AsyncData(result);
    return result;
  }

  FutureResult<ImageEntry, ExecError> updateImage(ImageEntry image) async {
    final List<ImageEntry> images = switch (state) {
      AsyncData(:final value) => value.fold(
          onSuccess: (images) => List.from(images),
          onError: (_) => <ImageEntry>[]),
      _ => <ImageEntry>[],
    };

    final index = images.indexOf(image);
    if (index < 0) {
      return buildErrorResult(
          type: ErrorType.notFound,
          message: 'Image ${image.id} does not exist for ${image.album}');
    }
    final result = await ref
        .read(editImageDataProvider(profile, image).future)
        .withResult((_) {
      images[index] = image;
    });

    state = AsyncData(result.transform((_) => images).execErrorCast());
    return result.execErrorCast();
  }

  FutureResult<ImageEntry, ExecError> deleteImage(ImageEntry image) async {
    final images = switch (state) {
      AsyncData(:final value) => value.fold(
          onSuccess: (images) => images.toSet(),
          onError: (_) => <ImageEntry>{}),
      _ => <ImageEntry>{},
    };

    if (!images.contains(image)) {
      return buildErrorResult(
          type: ErrorType.notFound,
          message: 'Image ${image.id} does not exist for ${image.album}');
    }

    final result = await ref
        .read(deleteImageProvider(profile, image).future)
        .withResult((_) => images.remove(image));

    state = AsyncData(result.transform((_) => images.toList()).execErrorCast());
    return result.execErrorCast();
  }

  void refresh() {
    ref.invalidateSelf();
  }
}

@riverpod
Future<Result<ImageEntry, ExecError>> galleryImage(
    Ref ref, Profile profile, String galleryName, String id) async {
  final result = await ref
      .read(galleryImagesProvider(profile, galleryName).future)
      .transform((images) => images.where((i) => i.id == id).toList())
      .andThen<ImageEntry, ExecError>((images) => images.isNotEmpty
          ? Result.ok(images.first)
          : buildErrorResult(
              type: ErrorType.notFound,
              message: 'Image $id not found in gallery $galleryName',
            ))
      .execErrorCastAsync();

  return result;
}