// Copyright (c) 2015, 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:mirrors';

import 'package:path/path.dart' as pathos;

/// Gets the test directory in a way that works with package:test
/// See <https://github.com/dart-lang/test/issues/110> for more info.
final String testDirectory = pathos.dirname(
  pathos.fromUri((reflectClass(_TestUtils).owner as LibraryMirror).uri),
);

/// Returns a path to the directory containing source code for packages such as
/// kernel, front_end, and analyzer.
String get packageRoot {
  // If the package root directory is specified on the command line using
  // -DpkgRoot=..., use it.
  var pkgRootVar = const bool.hasEnvironment('pkgRoot')
      ? const String.fromEnvironment('pkgRoot')
      : null;
  if (pkgRootVar != null) {
    var path = pathos.join(Directory.current.path, pkgRootVar);
    if (!path.endsWith(pathos.separator)) path += pathos.separator;
    return path;
  }
  // Otherwise try to guess based on the script path.
  var scriptPath = pathos.fromUri(Platform.script);
  var parts = pathos.split(scriptPath);
  var pkgIndex = parts.indexOf('pkg');
  if (pkgIndex != -1) {
    return pathos.joinAll(parts.sublist(0, pkgIndex + 1)) + pathos.separator;
  }
  throw StateError('Unable to find sdk/pkg/ in $scriptPath');
}

/// Recursively copy the specified [src] directory (or file)
/// to the specified destination path.
Future<void> recursiveCopy(FileSystemEntity src, String dstPath) async {
  if (src is Directory) {
    await Directory(dstPath).create(recursive: true);
    for (var entity in src.listSync()) {
      await recursiveCopy(
        entity,
        pathos.join(dstPath, pathos.basename(entity.path)),
      );
    }
  } else if (src is File) {
    await src.copy(dstPath);
  }
}

/// Creates a temporary directory and passes its path to [fn]. Once [fn]
/// completes, the temporary directory and all its contents will be deleted.
///
/// Returns the return value of [fn].
Future<dynamic> withTempDirAsync(
  Future<dynamic> Function(String path) fn,
) async {
  var tempDir = (await Directory.systemTemp.createTemp('analyzer_')).path;
  try {
    return await fn(tempDir);
  } finally {
    await Directory(tempDir).delete(recursive: true);
  }
}

class _TestUtils {}