// Copyright (c) 2013, 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.

library pub.command.cache;

import 'dart:async';
import 'dart:convert';

import '../command.dart';
import '../exit_codes.dart' as exit_codes;
import '../io.dart';
import '../log.dart' as log;

/// Handles the `cache` pub command.
class CacheCommand extends PubCommand {
  String get description => "Inspect the system cache.";
  String get usage => "pub cache list";
  bool get hidden => true;
  bool get requiresEntrypoint => false;
  bool get takesArguments => true;

  Future onRun() {
    // TODO(rnystrom): Use subcommand for "list".
    if (commandOptions.rest.length != 1) {
      log.error('The cache command expects one argument.');
      this.printUsage();
      return flushThenExit(exit_codes.USAGE);
    }

    if ((commandOptions.rest[0] != 'list')) {
      log.error('Unknown cache command "${commandOptions.rest[0]}".');
      this.printUsage();
      return flushThenExit(exit_codes.USAGE);
    }

    // TODO(keertip): Add flag to list packages from non default sources
    var packagesObj = <String, Map>{};

    for (var package in cache.sources.defaultSource.getCachedPackages()) {

      var packageInfo = packagesObj.putIfAbsent(package.name, () => {});
      packageInfo[package.version.toString()] = {'location': package.dir};
    }

    // TODO(keertip): Add support for non-JSON format
    // and check for --format flag
    log.message(JSON.encode({'packages': packagesObj}));
  }
}