// Copyright (c) 2019, the Dart project authors. Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.

import 'package:analysis_server/plugin/edit/assist/assist_core.dart';
import 'package:analysis_server/src/edit/fix/dartfix_listener.dart';
import 'package:analysis_server/src/edit/fix/dartfix_registrar.dart';
import 'package:analysis_server/src/edit/fix/fix_lint_task.dart';
import 'package:analysis_server/src/services/correction/assist.dart';
import 'package:analysis_server/src/services/correction/assist_internal.dart';
import 'package:analysis_server/src/services/correction/change_workspace.dart';
import 'package:analyzer/dart/analysis/results.dart';
import 'package:analyzer/error/error.dart';
import 'package:analyzer/src/dart/ast/utilities.dart';
import 'package:analyzer/src/lint/registry.dart';
import 'package:analyzer_plugin/utilities/assist/assist.dart';

class BasicFixLintAssistTask extends FixLintTask {
  final AssistKind assistKind;

  BasicFixLintAssistTask(this.assistKind, DartFixListener listener)
      : super(listener);

  @override
  Future<void> fixError(ResolvedUnitResult result, AnalysisError error) async {
    var node = new NodeLocator(error.offset).searchWithin(result.unit);
    AssistProcessor processor = new AssistProcessor(
      new DartAssistContextImpl(
        DartChangeWorkspace(listener.server.currentSessions),
        result,
        node.offset,
        node.length,
      ),
    );
    List<Assist> assists = await processor.computeAssist(assistKind);

    final location = listener.locationFor(result, node.offset, node.length);
    if (assists.isNotEmpty) {
      for (Assist assist in assists) {
        listener.addSourceChange(assist.kind.message, location, assist.change);
      }
    } else {
      // TODO(danrubel): If assists is empty, then determine why
      // assist could not be performed and report that in the description.
      listener.addRecommendation(
          'Fix not found: ${assistKind.message}', location);
    }
  }

  static void preferForElementsToMapFromIterable(
      DartFixRegistrar registrar, DartFixListener listener) {
    registrar.registerLintTask(
      Registry.ruleRegistry['prefer_for_elements_to_map_fromIterable'],
      new BasicFixLintAssistTask(
          DartAssistKind.CONVERT_TO_FOR_ELEMENT, listener),
    );
  }

  static void preferIfElementsToConditionalExpressions(
      DartFixRegistrar registrar, DartFixListener listener) {
    registrar.registerLintTask(
      Registry.ruleRegistry['prefer_if_elements_to_conditional_expressions'],
      new BasicFixLintAssistTask(
          DartAssistKind.CONVERT_TO_IF_ELEMENT, listener),
    );
  }

  static void preferIntLiterals(
      DartFixRegistrar registrar, DartFixListener listener) {
    registrar.registerLintTask(
      Registry.ruleRegistry['prefer_int_literals'],
      new BasicFixLintAssistTask(
          DartAssistKind.CONVERT_TO_INT_LITERAL, listener),
    );
  }

  static void preferSpreadCollections(
      DartFixRegistrar registrar, DartFixListener listener) {
    registrar.registerLintTask(
      Registry.ruleRegistry['prefer_spread_collections'],
      new BasicFixLintAssistTask(DartAssistKind.CONVERT_TO_SPREAD, listener),
    );
  }
}