// 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 'dart:async';

import 'lock_file.dart';
import 'package.dart';
import 'solver/failure.dart';
import 'solver/result.dart';
import 'solver/type.dart';
import 'solver/version_solver.dart';
import 'system_cache.dart';

export 'solver/failure.dart';
export 'solver/result.dart';
export 'solver/type.dart';

/// Attempts to select the best concrete versions for all of the transitive
/// dependencies of [root] taking into account all of the [VersionConstraint]s
/// that those dependencies place on each other and the requirements imposed by
/// [lockFile].
///
/// If [useLatest] is given, then only the latest versions of the referenced
/// packages will be used. This is for forcing an upgrade to one or more
/// packages.
///
/// If [upgradeAll] is true, the contents of [lockFile] are ignored.
Future<SolveResult> resolveVersions(
    SolveType type, SystemCache cache, Package root,
    {LockFile lockFile, Iterable<String> useLatest}) {
  return VersionSolver(
    type,
    cache,
    root,
    lockFile ?? LockFile.empty(),
    useLatest ?? const [],
  ).solve();
}

/// Attempts to select the best concrete versions for all of the transitive
/// dependencies of [root] taking into account all of the [VersionConstraint]s
/// that those dependencies place on each other and the requirements imposed by
/// [lockFile].
///
/// Like [resolveVersions] except that this function returns `null` where a
/// similar call to [resolveVersions] would throw a [SolveFailure].
///
/// If [useLatest] is given, then only the latest versions of the referenced
/// packages will be used. This is for forcing an upgrade to one or more
/// packages.
///
/// If [upgradeAll] is true, the contents of [lockFile] are ignored.
Future<SolveResult> tryResolveVersions(
    SolveType type, SystemCache cache, Package root,
    {LockFile lockFile, Iterable<String> useLatest}) async {
  try {
    return await resolveVersions(type, cache, root,
        lockFile: lockFile, useLatest: useLatest);
  } on SolveFailure {
    return null;
  }
}