// Copyright (c) 2017, 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:analyzer/error/error.dart';
import 'package:analyzer/src/generated/java_core.dart';
import 'package:analyzer_plugin/protocol/protocol_common.dart'
    hide AnalysisError;
import 'package:analyzer_plugin/protocol/protocol_generated.dart';
import 'package:analyzer_plugin/utilities/change_builder/change_builder_core.dart';
import 'package:analyzer_plugin/utilities/fixes/fixes.dart';

/**
 * A partial implementation of a [FixContributor] that iterates over the list of
 * errors and provides a utility method to make it easier to add fixes.
 *
 * Clients may not extend or implement this class, but are allowed to use it as
 * a mix-in when creating a subclass of [FixContributor].
 */
abstract class FixContributorMixin implements FixContributor {
  /**
   * The request that specifies the fixes that are to be built.
   */
  DartFixesRequest request;

  /**
   * The collector to which fixes should be added.
   */
  FixCollector collector;

  /**
   * Add a fix for the given [error]. Use the [kind] of the fix to get the
   * message and priority, and use the change [builder] to get the edits that
   * comprise the fix. If the message has parameters, then use the list of
   * [args] to populate the message.
   */
  void addFix(AnalysisError error, FixKind kind, ChangeBuilder builder,
      {List<Object> args}) {
    SourceChange change = builder.sourceChange;
    if (change.edits.isEmpty) {
      return;
    }
    change.message = formatList(kind.message, args);
    collector.addFix(error,
        new PrioritizedSourceChange(kind.priority, builder.sourceChange));
  }

  @override
  void computeFixes(DartFixesRequest request, FixCollector collector) {
    this.request = request;
    this.collector = collector;
    try {
      for (AnalysisError error in request.errorsToFix) {
        computeFixesForError(error);
      }
    } finally {
      this.request = null;
      this.collector = null;
    }
  }

  /**
   * Compute the fixes that are appropriate for the given [error] and add them
   * to the fix [collector].
   */
  void computeFixesForError(AnalysisError error);
}