// Copyright (c) 2016, 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.md file.

library fasta.testing.suite;

import 'dart:async' show Future;

import 'dart:io' show File;

import 'dart:convert' show JSON;

import 'package:front_end/physical_file_system.dart' show PhysicalFileSystem;

import 'package:front_end/src/base/libraries_specification.dart'
    show TargetLibrariesSpecification;

import 'package:front_end/src/fasta/testing/validating_instrumentation.dart'
    show ValidatingInstrumentation;

import 'package:front_end/src/fasta/testing/patched_sdk_location.dart'
    show computeDartVm, computePatchedSdk;
import 'package:front_end/src/fasta/uri_translator_impl.dart';

import 'package:kernel/ast.dart' show Library, Program;

import 'package:testing/testing.dart'
    show
        Chain,
        ChainContext,
        ExpectationSet,
        Result,
        Step,
        TestDescription,
        StdioProcess;

import 'package:front_end/compiler_options.dart' show CompilerOptions;

import 'package:front_end/src/base/processed_options.dart'
    show ProcessedOptions;

import 'package:front_end/src/fasta/compiler_context.dart' show CompilerContext;

import 'package:front_end/src/fasta/deprecated_problems.dart'
    show deprecated_InputError;

import 'package:front_end/src/fasta/testing/kernel_chain.dart'
    show MatchExpectation, Print, Verify, WriteDill;

import 'package:front_end/src/fasta/ticker.dart' show Ticker;

import 'package:front_end/src/fasta/uri_translator.dart' show UriTranslator;

import 'package:analyzer/src/fasta/analyzer_target.dart' show AnalyzerTarget;

import 'package:front_end/src/fasta/kernel/kernel_target.dart'
    show KernelTarget;

import 'package:front_end/src/fasta/dill/dill_target.dart' show DillTarget;

import 'package:kernel/kernel.dart' show loadProgramFromBytes;

import 'package:kernel/target/targets.dart' show TargetFlags;

import 'package:kernel/target/vm_fasta.dart' show VmFastaTarget;

import 'package:kernel/class_hierarchy.dart' show ClassHierarchy;

import 'package:kernel/core_types.dart' show CoreTypes;

export 'package:testing/testing.dart' show Chain, runMe;

const String STRONG_MODE = " strong mode ";

const String ENABLE_FULL_COMPILE = " full compile ";

const String AST_KIND_INDEX = " AST kind index ";

const String EXPECTATIONS = '''
[
  {
    "name": "VerificationError",
    "group": "Fail"
  }
]
''';

String generateExpectationName(bool strongMode) {
  return strongMode ? "strong" : "direct";
}

enum AstKind {
  Analyzer,
  Kernel,
}

class FastaContext extends ChainContext {
  final UriTranslatorImpl uriTranslator;
  final List<Step> steps;
  final Uri vm;
  final Map<Program, KernelTarget> programToTarget = <Program, KernelTarget>{};
  Uri sdk;
  Uri platformUri;
  Uri outlineUri;
  Program outline;

  final ExpectationSet expectationSet =
      new ExpectationSet.fromJsonList(JSON.decode(EXPECTATIONS));

  FastaContext(
      this.vm,
      bool strongMode,
      bool updateExpectations,
      bool updateComments,
      bool skipVm,
      this.uriTranslator,
      bool fullCompile,
      AstKind astKind)
      : steps = <Step>[
          new Outline(fullCompile, astKind, strongMode,
              updateComments: updateComments),
          const Print(),
          new Verify(fullCompile)
        ] {
    if (astKind != AstKind.Analyzer) {
      steps.add(new MatchExpectation(
          fullCompile
              ? ".${generateExpectationName(strongMode)}.expect"
              : ".outline.expect",
          updateExpectations: updateExpectations));
      if (fullCompile && !skipVm) {
        steps.add(const Transform());
        steps.add(const WriteDill());
        steps.add(const Run());
      }
    }
  }

  Future ensurePlatformUris() async {
    if (sdk == null) {
      sdk = await computePatchedSdk();
      platformUri = sdk.resolve('platform.dill');
      outlineUri = sdk.resolve('outline.dill');
    }
  }

  Future<Program> loadPlatformOutline() async {
    if (outline == null) {
      await ensurePlatformUris();
      outline =
          loadProgramFromBytes(new File.fromUri(outlineUri).readAsBytesSync());
    }
    return outline;
  }

  static Future<FastaContext> create(
      Chain suite, Map<String, String> environment) async {
    Uri sdk = await computePatchedSdk();
    Uri vm = computeDartVm(sdk);
    Uri packages = Uri.base.resolve(".packages");
    var options = new ProcessedOptions(new CompilerOptions()
      ..sdkRoot = sdk
      ..packagesFileUri = packages);
    UriTranslator uriTranslator = await options.getUriTranslator();
    bool strongMode = environment.containsKey(STRONG_MODE);
    bool updateExpectations = environment["updateExpectations"] == "true";
    bool updateComments = environment["updateComments"] == "true";
    bool skipVm = environment["skipVm"] == "true";
    String astKindString = environment[AST_KIND_INDEX];
    AstKind astKind =
        astKindString == null ? null : AstKind.values[int.parse(astKindString)];
    return new FastaContext(
        vm,
        strongMode,
        updateExpectations,
        updateComments,
        skipVm,
        uriTranslator,
        environment.containsKey(ENABLE_FULL_COMPILE),
        astKind);
  }
}

class Run extends Step<Uri, int, FastaContext> {
  const Run();

  String get name => "run";

  bool get isAsync => true;

  bool get isRuntime => true;

  Future<Result<int>> run(Uri uri, FastaContext context) async {
    if (context.platformUri == null) {
      throw "Executed `Run` step before initializing the context.";
    }
    File generated = new File.fromUri(uri);
    StdioProcess process;
    try {
      var sdkPath = context.sdk.toFilePath();
      var args = [
        '--kernel-binaries=$sdkPath',
        generated.path,
        "Hello, World!"
      ];
      process = await StdioProcess.run(context.vm.toFilePath(), args);
      print(process.output);
    } finally {
      generated.parent.delete(recursive: true);
    }
    return process.toResult();
  }
}

class Outline extends Step<TestDescription, Program, FastaContext> {
  final bool fullCompile;

  final AstKind astKind;

  final bool strongMode;

  const Outline(this.fullCompile, this.astKind, this.strongMode,
      {this.updateComments: false});

  final bool updateComments;

  String get name {
    return fullCompile ? "${astKind} compile" : "outline";
  }

  bool get isCompiler => fullCompile;

  Future<Result<Program>> run(
      TestDescription description, FastaContext context) async {
    var options = new ProcessedOptions(new CompilerOptions());
    return await CompilerContext.runWithOptions(options, (_) async {
      // Disable colors to ensure that expectation files are the same across
      // platforms and independent of stdin/stderr.
      CompilerContext.current.disableColors();
      Program platformOutline = await context.loadPlatformOutline();
      Ticker ticker = new Ticker();
      DillTarget dillTarget = new DillTarget(ticker, context.uriTranslator,
          new TestVmFastaTarget(new TargetFlags(strongMode: strongMode)));
      dillTarget.loader.appendLibraries(platformOutline);
      // We create a new URI translator to avoid reading platform libraries from
      // file system.
      UriTranslatorImpl uriTranslator = new UriTranslatorImpl(
          const TargetLibrariesSpecification('vm'),
          context.uriTranslator.packages);
      KernelTarget sourceTarget = astKind == AstKind.Analyzer
          ? new AnalyzerTarget(dillTarget, uriTranslator, strongMode)
          : new KernelTarget(
              PhysicalFileSystem.instance, false, dillTarget, uriTranslator);

      Program p;
      try {
        sourceTarget.read(description.uri);
        await dillTarget.buildOutlines();
        ValidatingInstrumentation instrumentation;
        if (strongMode) {
          instrumentation = new ValidatingInstrumentation();
          await instrumentation.loadExpectations(description.uri);
          sourceTarget.loader.instrumentation = instrumentation;
        }
        p = await sourceTarget.buildOutlines();
        if (fullCompile) {
          p = await sourceTarget.buildProgram();
          instrumentation?.finish();
          if (instrumentation != null && instrumentation.hasProblems) {
            if (updateComments) {
              await instrumentation.fixSource(description.uri, false);
            } else {
              return fail(null, instrumentation.problemsAsString);
            }
          }
        }
      } on deprecated_InputError catch (e, s) {
        return fail(null, e.error, s);
      }
      context.programToTarget.clear();
      context.programToTarget[p] = sourceTarget;
      return pass(p);
    });
  }
}

class Transform extends Step<Program, Program, FastaContext> {
  const Transform();

  String get name => "transform program";

  Future<Result<Program>> run(Program program, FastaContext context) async {
    KernelTarget sourceTarget = context.programToTarget[program];
    context.programToTarget.remove(program);
    TestVmFastaTarget backendTarget = sourceTarget.backendTarget;
    backendTarget.enabled = true;
    try {
      if (sourceTarget.loader.coreTypes != null) {
        sourceTarget.runBuildTransformations();
      }
    } finally {
      backendTarget.enabled = false;
    }
    return pass(program);
  }
}

class TestVmFastaTarget extends VmFastaTarget {
  bool enabled = false;

  TestVmFastaTarget(TargetFlags flags) : super(flags);

  String get name => "vm_fasta";

  void performModularTransformationsOnLibraries(
      CoreTypes coreTypes, ClassHierarchy hierarchy, List<Library> libraries,
      {void logger(String msg)}) {
    if (enabled) {
      super.performModularTransformationsOnLibraries(
          coreTypes, hierarchy, libraries,
          logger: logger);
    }
  }

  void performGlobalTransformations(CoreTypes coreTypes, Program program,
      {void logger(String msg)}) {
    if (enabled) {
      super.performGlobalTransformations(coreTypes, program, logger: logger);
    }
  }
}