// 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 'dart:io';
import 'dart:convert';

import 'package:args/command_runner.dart';

import 'package:dart2js_info/info.dart';
import 'package:dart2js_info/json_info_codec.dart';
import 'package:dart2js_info/src/io.dart';

import 'inject_text.dart';
import 'usage_exception.dart';

/// Converts a dump-info file emitted by dart2js in binary format to JSON.
class ToJsonCommand extends Command<void> with PrintUsageException {
  final String name = "to_json";
  final String description = "Convert any info file to JSON format.";

  ToJsonCommand() {
    argParser.addOption('out',
        abbr: 'o', help: 'Output file (defauts to <input>.json)');

    argParser.addFlag('inject-text',
        negatable: false,
        help: 'Whether to inject output code snippets.\n\n'
            'By default dart2js produces code spans, but excludes the text. This\n'
            'option can be used to embed the text directly in the output JSON.\n'
            'This is implied by `--compat-mode`.');

    argParser.addFlag('compat-mode',
        negatable: false,
        help: 'Whether to generate an older version of the JSON format.\n\n'
            'By default files are converted to the latest JSON format, but\n'
            'passing `--compat-mode` will produce a JSON file that may still\n'
            'work in the visualizer tool at:\n'
            'https://dart-lang.github.io/dump-info-visualizer/.\n\n'
            'Note, however, that files produced in this mode do not contain\n'
            'all the data available in the input file.');
  }

  void run() async {
    if (argResults.rest.length < 1) {
      usageException('Missing argument: <input-info>');
    }

    String filename = argResults.rest[0];
    bool isBackwardCompatible = argResults['compat-mode'];
    AllInfo info = await infoFromFile(filename);

    if (isBackwardCompatible || argResults['inject-text']) {
      injectText(info);
    }

    var json = new AllInfoJsonCodec(isBackwardCompatible: isBackwardCompatible)
        .encode(info);
    String outputFilename = argResults['out'] ?? '$filename.json';
    new File(outputFilename)
        .writeAsStringSync(const JsonEncoder.withIndent("  ").convert(json));
  }
}