pkg/analysis_server/lib/src/handler/legacy/analysis_get_hover.dart

// Copyright (c) 2022, 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 'dart:async';

import 'package:analysis_server/protocol/protocol.dart';
import 'package:analysis_server/protocol/protocol_generated.dart';
import 'package:analysis_server/src/computer/computer_hover.dart';
import 'package:analysis_server/src/handler/legacy/legacy_handler.dart';
import 'package:analyzer/dart/analysis/results.dart';

/// The handler for the `analysis.getHover` request.
class AnalysisGetHoverHandler extends LegacyHandler {
  /// Initialize a newly created handler to be able to service requests for the
  /// [server].
  new(super.server, super.request, super.cancellationToken, super.performance);

  @override
  Future<void> handle() async {
    var params = AnalysisGetHoverParams.fromRequest(
      request,
      clientUriConverter: server.uriConverter,
    );
    var file = params.file;

    if (server.sendResponseErrorIfInvalidFilePath(request, file)) {
      return;
    }

    // Prepare the resolved units.
    var result = await performance.runAsync(
      'getResolvedUnit',
      (_) async => await server.getResolvedUnit(file),
    );
    if (result is! ResolvedUnitResult) {
      sendResponse(Response.fileNotAnalyzed(request, file));
      return;
    }
    var unit = result.unit;

    // Prepare the hovers.
    var hovers = <HoverInformation>[];
    var computer = DartUnitHoverComputer(
      server.getDartdocDirectiveInfoFor(result),
      unit,
      params.offset,
    );
    var hoverInformation = performance.run(
      'compute',
      (_) => computer.compute(),
    );
    if (hoverInformation != null) {
      hovers.add(hoverInformation);
    }

    // Send the response.
    sendResult(AnalysisGetHoverResult(hovers));
  }
}