// 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 test;

import 'dart:async';

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

import 'src/backend/declarer.dart';
import 'src/backend/test_platform.dart';
import 'src/frontend/timeout.dart';
import 'src/runner/engine.dart';
import 'src/runner/reporter/expanded.dart';
import 'src/runner/runner_suite.dart';
import 'src/runner/vm/environment.dart';
import 'src/utils.dart';

export 'package:matcher/matcher.dart';

export 'src/frontend/expect.dart';
export 'src/frontend/expect_async.dart';
export 'src/frontend/future_matchers.dart';
export 'src/frontend/on_platform.dart';
export 'src/frontend/prints_matcher.dart';
export 'src/frontend/skip.dart';
export 'src/frontend/test_on.dart';
export 'src/frontend/throws_matcher.dart';
export 'src/frontend/throws_matchers.dart';
export 'src/frontend/timeout.dart';

/// The global declarer.
///
/// This is used if a test file is run directly, rather than through the runner.
Declarer _globalDeclarer;

/// Gets the declarer for the current scope.
///
/// When using the runner, this returns the [Zone]-scoped declarer that's set by
/// [IsolateListener] or [IframeListener]. If the test file is run directly,
/// this returns [_globalDeclarer] (and sets it up on the first call).
Declarer get _declarer {
  var declarer = Declarer.current;
  if (declarer != null) return declarer;
  if (_globalDeclarer != null) return _globalDeclarer;

  // Since there's no Zone-scoped declarer, the test file is being run directly.
  // In order to run the tests, we set up our own Declarer via
  // [_globalDeclarer], and schedule a microtask to run the tests once they're
  // finished being defined.
  _globalDeclarer = new Declarer();
  scheduleMicrotask(() async {
    var suite = new RunnerSuite(
        // TODO(nweiz): Use a different environment if VM environment starts
        // import dart:io before cross-platform libraries exist.
        const VMEnvironment(),
        _globalDeclarer.build(),
        path: p.prettyUri(Uri.base),
        platform: TestPlatform.vm,
        os: currentOSGuess);

    var engine = new Engine();
    engine.suiteSink.add(suite);
    engine.suiteSink.close();
    ExpandedReporter.watch(engine,
        color: true, printPath: false, printPlatform: false);

    var success = await engine.run();
    // TODO(nweiz): Set the exit code on the VM when issue 6943 is fixed.
    if (success) return;
    print('');
    new Future.error("Dummy exception to set exit code.");
  });
  return _globalDeclarer;
}

// TODO(nweiz): This and other top-level functions should throw exceptions if
// they're called after the declarer has finished declaring.
/// Creates a new test case with the given description and body.
///
/// The description will be added to the descriptions of any surrounding
/// [group]s. If [testOn] is passed, it's parsed as a [platform selector][]; the
/// test will only be run on matching platforms.
///
/// [platform selector]: https://github.com/dart-lang/test/#platform-selector-syntax
///
/// If [timeout] is passed, it's used to modify or replace the default timeout
/// of 30 seconds. Timeout modifications take precedence in suite-group-test
/// order, so [timeout] will also modify any timeouts set on the group or suite.
///
/// If [skip] is a String or `true`, the test is skipped. If it's a String, it
/// should explain why the test is skipped; this reason will be printed instead
/// of running the test.
///
/// [onPlatform] allows tests to be configured on a platform-by-platform
/// basis. It's a map from strings that are parsed as [PlatformSelector]s to
/// annotation classes: [Timeout], [Skip], or lists of those. These
/// annotations apply only on the given platforms. For example:
///
///     test("potentially slow test", () {
///       // ...
///     }, onPlatform: {
///       // This test is especially slow on Windows.
///       "windows": new Timeout.factor(2),
///       "browser": [
///         new Skip("TODO: add browser support"),
///         // This will be slow on browsers once it works on them.
///         new Timeout.factor(2)
///       ]
///     });
///
/// If multiple platforms match, the annotations apply in order as through
/// they were in nested groups.
void test(String description, body(), {String testOn, Timeout timeout,
        skip, Map<String, dynamic> onPlatform}) =>
    _declarer.test(description, body,
        testOn: testOn, timeout: timeout, skip: skip, onPlatform: onPlatform);

/// Creates a group of tests.
///
/// A group's description is included in the descriptions of any tests or
/// sub-groups it contains. [setUp] and [tearDown] are also scoped to the
/// containing group.
///
/// If [testOn] is passed, it's parsed as a [platform selector][]; the test will
/// only be run on matching platforms.
///
/// [platform selector]: https://github.com/dart-lang/test/#platform-selector-syntax
///
/// If [timeout] is passed, it's used to modify or replace the default timeout
/// of 30 seconds. Timeout modifications take precedence in suite-group-test
/// order, so [timeout] will also modify any timeouts set on the suite, and will
/// be modified by any timeouts set on individual tests.
///
/// If [skip] is a String or `true`, the group is skipped. If it's a String, it
/// should explain why the group is skipped; this reason will be printed instead
/// of running the group's tests.
///
/// [onPlatform] allows groups to be configured on a platform-by-platform
/// basis. It's a map from strings that are parsed as [PlatformSelector]s to
/// annotation classes: [Timeout], [Skip], or lists of those. These
/// annotations apply only on the given platforms. For example:
///
///     group("potentially slow tests", () {
///       // ...
///     }, onPlatform: {
///       // These tests are especially slow on Windows.
///       "windows": new Timeout.factor(2),
///       "browser": [
///         new Skip("TODO: add browser support"),
///         // They'll be slow on browsers once it works on them.
///         new Timeout.factor(2)
///       ]
///     });
///
/// If multiple platforms match, the annotations apply in order as through
/// they were in nested groups.
void group(String description, void body(), {String testOn, Timeout timeout,
        skip, Map<String, dynamic> onPlatform}) =>
    _declarer.group(description, body,
        testOn: testOn, timeout: timeout, skip: skip);

/// Registers a function to be run before tests.
///
/// This function will be called before each test is run. [callback] may be
/// asynchronous; if so, it must return a [Future].
///
/// If this is called within a test group, it applies only to tests in that
/// group. [callback] will be run after any set-up callbacks in parent groups or
/// at the top level.
///
/// Each callback at the top level or in a given group will be run in the order
/// they were declared.
void setUp(callback()) => _declarer.setUp(callback);

/// Registers a function to be run after tests.
///
/// This function will be called after each test is run. [callback] may be
/// asynchronous; if so, it must return a [Future].
///
/// If this is called within a test group, it applies only to tests in that
/// group. [callback] will be run before any tear-down callbacks in parent
/// groups or at the top level.
///
/// Each callback at the top level or in a given group will be run in the
/// reverse of the order they were declared.
void tearDown(callback()) => _declarer.tearDown(callback);

/// Registers a function to be run once before all tests.
///
/// [callback] may be asynchronous; if so, it must return a [Future].
///
/// If this is called within a test group, [callback] will run before all tests
/// in that group. It will be run after any [setUpAll] callbacks in parent
/// groups or at the top level. It won't be run if none of the tests in the
/// group are run.
///
/// **Note**: This function makes it very easy to accidentally introduce hidden
/// dependencies between tests that should be isolated. In general, you should
/// prefer [setUp], and only use [setUpAll] if the callback is prohibitively
/// slow.
void setUpAll(callback()) => _declarer.setUpAll(callback);

/// Registers a function to be run once after all tests.
///
/// If this is called within a test group, [callback] will run after all tests
/// in that group. It will be run before any [tearDownAll] callbacks in parent
/// groups or at the top level. It won't be run if none of the tests in the
/// group are run.
///
/// **Note**: This function makes it very easy to accidentally introduce hidden
/// dependencies between tests that should be isolated. In general, you should
/// prefer [tearDown], and only use [tearDOwnAll] if the callback is
/// prohibitively slow.
void tearDownAll(callback()) => _declarer.tearDownAll(callback);

/// Registers an exception that was caught for the current test.
void registerException(error, [StackTrace stackTrace]) {
  // This will usually forward directly to [Invoker.current.handleError], but
  // going through the zone API allows other zones to consistently see errors.
  Zone.current.handleUncaughtError(error, stackTrace);
}