// 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.

import 'dart:async';

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

import 'src/backend/declarer.dart';
import 'src/backend/invoker.dart';
import 'src/backend/test_platform.dart';
import 'src/frontend/timeout.dart';
import 'src/runner/configuration/suite.dart';
import 'src/runner/engine.dart';
import 'src/runner/plugin/environment.dart';
import 'src/runner/reporter/expanded.dart';
import 'src/runner/runner_suite.dart';
import 'src/utils.dart';

export 'package:matcher/matcher.dart';

export 'src/frontend/expect.dart' hide formatFailure;
export 'src/frontend/expect_async.dart';
export 'src/frontend/future_matchers.dart';
export 'src/frontend/on_platform.dart';
export 'src/frontend/never_called.dart';
export 'src/frontend/prints_matcher.dart';
export 'src/frontend/skip.dart';
export 'src/frontend/spawn_hybrid.dart';
export 'src/frontend/stream_matcher.dart';
export 'src/frontend/stream_matchers.dart';
export 'src/frontend/tags.dart';
export 'src/frontend/test_on.dart';
export 'src/frontend/throws_matcher.dart';
export 'src/frontend/throws_matchers.dart';
export 'src/frontend/timeout.dart';
export 'src/frontend/utils.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(const PluginEnvironment(),
        SuiteConfiguration.empty, _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 runZoned(() => Invoker.guard(engine.run),
        zoneValues: {#test.declarer: _globalDeclarer});
    // TODO(nweiz): Set the exit code on the VM when issue 6943 is fixed.
    if (success) return null;
    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 (converted to a string)
/// 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.
///
/// If [tags] is passed, it declares user-defined tags that are applied to the
/// test. These tags can be used to select or skip the test on the command line,
/// or to do bulk test configuration. All tags should be declared in the
/// [package configuration file][configuring tags]. The parameter can be an
/// [Iterable] of tag names, or a [String] representing a single tag.
///
/// If [retry] is passed, the test will be retried the provided number of times
/// before being marked as a failure.
///
/// [configuring tags]: https://github.com/dart-lang/test/blob/master/doc/package_config.md#configuring-tags
///
/// [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(description, body(),
    {String testOn,
    Timeout timeout,
    skip,
    tags,
    Map<String, dynamic> onPlatform,
    int retry}) {
  _declarer.test(description.toString(), body,
      testOn: testOn,
      timeout: timeout,
      skip: skip,
      onPlatform: onPlatform,
      tags: tags,
      retry: retry);

  // Force dart2js not to inline this function. We need it to be separate from
  // `main()` in JS stack traces in order to properly determine the line and
  // column where the test was defined. See sdk#26705.
  return;
  return; // ignore: dead_code
}

/// Creates a group of tests.
///
/// A group's description (converted to a string) 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.
///
/// If [tags] is passed, it declares user-defined tags that are applied to the
/// test. These tags can be used to select or skip the test on the command line,
/// or to do bulk test configuration. All tags should be declared in the
/// [package configuration file][configuring tags]. The parameter can be an
/// [Iterable] of tag names, or a [String] representing a single tag.
///
/// [configuring tags]: https://github.com/dart-lang/test/blob/master/doc/package_config.md#configuring-tags
///
/// [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(description, body(),
    {String testOn,
    Timeout timeout,
    skip,
    tags,
    Map<String, dynamic> onPlatform,
    int retry}) {
  _declarer.group(description.toString(), body,
      testOn: testOn,
      timeout: timeout,
      skip: skip,
      tags: tags,
      onPlatform: onPlatform,
      retry: retry);

  // Force dart2js not to inline this function. We need it to be separate from
  // `main()` in JS stack traces in order to properly determine the line and
  // column where the test was defined. See sdk#26705.
  return;
  return; // ignore: dead_code
}

/// 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.
///
/// See also [addTearDown], which adds tear-downs to a running test.
void tearDown(callback()) => _declarer.tearDown(callback);

/// Registers a function to be run after the current test.
///
/// This is called within a running test, and adds a tear-down only for the
/// current test. It allows testing libraries to add cleanup logic as soon as
/// there's something to clean up.
///
/// The [callback] is run before any callbacks registered with [tearDown]. Like
/// [tearDown], the most recently registered callback is run first.
///
/// If this is called from within a [setUpAll] or [tearDownAll] callback, it
/// instead runs the function after *all* tests in the current test suite.
void addTearDown(callback()) {
  if (Invoker.current == null) {
    throw new StateError("addTearDown() may only be called within a test.");
  }

  Invoker.current.addTearDown(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);
}

/// Prints [message] if and when the current test fails.
///
/// This is intended for test infrastructure to provide debugging information
/// without cluttering the output for successful tests. Note that unlike
/// [print], each individual message passed to [printOnFailure] will be
/// separated by a blank line.
void printOnFailure(String message) => Invoker.current.printOnFailure(message);