AppFlowy/frontend/app_flowy/lib/plugins/board/application/board_bloc.dart

import 'dart:async';
import 'package:app_flowy/plugins/grid/application/block/block_cache.dart';
import 'package:app_flowy/plugins/grid/application/grid_data_controller.dart';
import 'package:app_flowy/plugins/grid/application/row/row_cache.dart';
import 'package:appflowy_board/appflowy_board.dart';
import 'package:dartz/dartz.dart';
import 'package:equatable/equatable.dart';
import 'package:flowy_sdk/protobuf/flowy-error/errors.pb.dart';
import 'package:flowy_sdk/protobuf/flowy-folder/view.pb.dart';
import 'package:flowy_sdk/protobuf/flowy-grid/protobuf.dart';
import 'package:flutter_bloc/flutter_bloc.dart';
import 'package:freezed_annotation/freezed_annotation.dart';
import 'dart:collection';

part 'board_bloc.freezed.dart';

class BoardBloc extends Bloc<BoardEvent, BoardState> {
  final GridDataController _gridDataController;
  late final BoardDataController boardDataController;

  BoardBloc({required ViewPB view})
      : _gridDataController = GridDataController(view: view),
        super(BoardState.initial(view.id)) {
    boardDataController = BoardDataController(
      onMoveColumn: (
        fromIndex,
        toIndex,
      ) {},
      onMoveColumnItem: (
        columnId,
        fromIndex,
        toIndex,
      ) {},
      onMoveColumnItemToColumn: (
        fromColumnId,
        fromIndex,
        toColumnId,
        toIndex,
      ) {},
    );

    // boardDataController.addColumns(_buildColumns());

    on<BoardEvent>(
      (event, emit) async {
        await event.when(
          initial: () async {
            _startListening();
            await _loadGrid(emit);
          },
          createRow: () {
            _gridDataController.createRow();
          },
          didReceiveGridUpdate: (GridPB grid) {
            emit(state.copyWith(grid: Some(grid)));
          },
          didReceiveFieldUpdate: (UnmodifiableListView<GridFieldPB> fields) {
            emit(state.copyWith(fields: GridFieldEquatable(fields)));
          },
          didReceiveRowUpdate: (
            List<GridRowInfo> newRowInfos,
            GridRowChangeReason reason,
          ) {
            emit(state.copyWith(rowInfos: newRowInfos, reason: reason));
          },
        );
      },
    );
  }

  @override
  Future<void> close() async {
    await _gridDataController.dispose();
    return super.close();
  }

  GridRowCache? getRowCache(String blockId, String rowId) {
    final GridBlockCache? blockCache = _gridDataController.blocks[blockId];
    return blockCache?.rowCache;
  }

  void _startListening() {
    _gridDataController.addListener(
      onGridChanged: (grid) {
        if (!isClosed) {
          add(BoardEvent.didReceiveGridUpdate(grid));
        }
      },
      onRowsChanged: (rowInfos, reason) {
        if (!isClosed) {
          add(BoardEvent.didReceiveRowUpdate(rowInfos, reason));
        }
      },
      onFieldsChanged: (fields) {
        if (!isClosed) {
          _buildColumns(fields);
          add(BoardEvent.didReceiveFieldUpdate(fields));
        }
      },
    );
  }

  void _buildColumns(UnmodifiableListView<GridFieldPB> fields) {
    List<BoardColumnData> columns = [];

    for (final field in fields) {
      if (field.fieldType == FieldType.SingleSelect) {
        //  return BoardColumnData(customData: field, id: field.id, desc: "1");
      }
    }

    boardDataController.addColumns(columns);

    // final column1 = BoardColumnData(id: "To Do", items: [
    //   TextItem("Card 1"),
    //   TextItem("Card 2"),
    //   RichTextItem(title: "Card 3", subtitle: 'Aug 1, 2020 4:05 PM'),
    //   TextItem("Card 4"),
    // ]);
    // final column2 = BoardColumnData(id: "In Progress", items: [
    //   RichTextItem(title: "Card 5", subtitle: 'Aug 1, 2020 4:05 PM'),
    //   TextItem("Card 6"),
    // ]);

    // final column3 = BoardColumnData(id: "Done", items: []);
    // boardDataController.addColumn(column1);
    // boardDataController.addColumn(column2);
    // boardDataController.addColumn(column3);
  }

  Future<void> _loadGrid(Emitter<BoardState> emit) async {
    final result = await _gridDataController.loadData();
    result.fold(
      (grid) => emit(
        state.copyWith(loadingState: GridLoadingState.finish(left(unit))),
      ),
      (err) => emit(
        state.copyWith(loadingState: GridLoadingState.finish(right(err))),
      ),
    );
  }
}

@freezed
class BoardEvent with _$BoardEvent {
  const factory BoardEvent.initial() = InitialGrid;
  const factory BoardEvent.createRow() = _CreateRow;
  const factory BoardEvent.didReceiveRowUpdate(
    List<GridRowInfo> rows,
    GridRowChangeReason listState,
  ) = _DidReceiveRowUpdate;
  const factory BoardEvent.didReceiveFieldUpdate(
    UnmodifiableListView<GridFieldPB> fields,
  ) = _DidReceiveFieldUpdate;

  const factory BoardEvent.didReceiveGridUpdate(
    GridPB grid,
  ) = _DidReceiveGridUpdate;
}

@freezed
class BoardState with _$BoardState {
  const factory BoardState({
    required String gridId,
    required Option<GridPB> grid,
    required GridFieldEquatable fields,
    required List<GridRowInfo> rowInfos,
    required GridLoadingState loadingState,
    required GridRowChangeReason reason,
  }) = _BoardState;

  factory BoardState.initial(String gridId) => BoardState(
        fields: GridFieldEquatable(UnmodifiableListView([])),
        rowInfos: [],
        grid: none(),
        gridId: gridId,
        loadingState: const _Loading(),
        reason: const InitialListState(),
      );
}

@freezed
class GridLoadingState with _$GridLoadingState {
  const factory GridLoadingState.loading() = _Loading;
  const factory GridLoadingState.finish(
      Either<Unit, FlowyError> successOrFail) = _Finish;
}

class GridFieldEquatable extends Equatable {
  final UnmodifiableListView<GridFieldPB> _fields;
  const GridFieldEquatable(
    UnmodifiableListView<GridFieldPB> fields,
  ) : _fields = fields;

  @override
  List<Object?> get props {
    if (_fields.isEmpty) {
      return [];
    }

    return [
      _fields.length,
      _fields
          .map((field) => field.width)
          .reduce((value, element) => value + element),
    ];
  }

  UnmodifiableListView<GridFieldPB> get value => UnmodifiableListView(_fields);
}

class TextItem extends ColumnItem {
  final String s;

  TextItem(this.s);

  @override
  String get id => s;
}

class RichTextItem extends ColumnItem {
  final String title;
  final String subtitle;

  RichTextItem({required this.title, required this.subtitle});

  @override
  String get id => title;
}