// Copyright (c) 2012, 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 compiler_helper;

import 'dart:async';
import "package:expect/expect.dart";

import 'package:compiler/compiler_new.dart';

import 'package:compiler/src/common_elements.dart';

import 'package:compiler/src/elements/elements.dart';
import 'package:compiler/src/elements/entities.dart';
export 'package:compiler/src/elements/elements.dart';

import 'package:compiler/src/js_backend/js_backend.dart' as js;
import 'package:compiler/src/js_backend/element_strategy.dart'
    show ElementCodegenWorkItem;

import 'package:compiler/src/commandline_options.dart';
import 'package:compiler/src/common/codegen.dart';
import 'package:compiler/src/common/resolution.dart';

export 'package:compiler/src/diagnostics/messages.dart';
export 'package:compiler/src/diagnostics/source_span.dart';
export 'package:compiler/src/diagnostics/spannable.dart';

export 'package:compiler/src/types/types.dart' show TypeMask;

import 'package:compiler/src/util/util.dart';
export 'package:compiler/src/util/util.dart';

import 'package:compiler/src/world.dart';

import 'package:compiler/src/compiler.dart' show Compiler;

export 'package:compiler/src/tree/tree.dart';

import 'mock_compiler.dart';
export 'mock_compiler.dart';

import 'memory_compiler.dart' hide compilerFor;

import 'output_collector.dart';
export 'output_collector.dart';

enum CompileMode { mock, memory, kernel }

/// Compile [code] and returns either the code for [entry] or, if [returnAll] is
/// true, the code for the entire program.
///
/// If [check] is provided, it is executed on the code for [entry] before
/// returning. If [useMock] is `true` the [MockCompiler] is used for
/// compilation, otherwise the memory compiler is used.
Future<String> compile(String code,
    {String entry: 'main',
    bool enableTypeAssertions: false,
    bool minify: false,
    bool analyzeAll: false,
    bool disableInlining: true,
    bool trustJSInteropTypeAnnotations: false,
    CompileMode compileMode: CompileMode.memory,
    void check(String generatedEntry),
    bool returnAll: false}) async {
  OutputCollector outputCollector = returnAll ? new OutputCollector() : null;
  if (compileMode == CompileMode.mock) {
    // TODO(johnniwinther): Remove this when no longer needed by
    // `arithmetic_simplication_test.dart`.
    MockCompiler compiler = new MockCompiler.internal(
        enableTypeAssertions: enableTypeAssertions,
        // Type inference does not run when manually
        // compiling a method.
        disableTypeInference: true,
        enableMinification: minify,
        disableInlining: disableInlining,
        trustJSInteropTypeAnnotations: trustJSInteropTypeAnnotations,
        outputProvider: outputCollector);
    await compiler.init();
    compiler.parseScript(code);
    ElementEnvironment elementEnvironment =
        compiler.frontendStrategy.elementEnvironment;
    MethodElement element = compiler.mainApp.find(entry);
    if (element == null) return null;
    compiler.phase = Compiler.PHASE_RESOLVING;
    compiler.processQueue(elementEnvironment, compiler.enqueuer.resolution,
        element, compiler.libraryLoader.libraries);
    ResolutionWorkItem resolutionWork =
        new ResolutionWorkItem(compiler.resolution, element);
    resolutionWork.run();
    ClosedWorld closedWorld = compiler.closeResolution(element).closedWorld;
    CodegenWorkItem work =
        new ElementCodegenWorkItem(compiler.backend, closedWorld, element);
    compiler.phase = Compiler.PHASE_COMPILING;
    work.run();
    js.JavaScriptBackend backend = compiler.backend;
    String generated = backend.getGeneratedCode(element);
    if (check != null) {
      check(generated);
    }
    return returnAll ? outputCollector.getOutput('', OutputType.js) : generated;
  } else {
    List<String> options = <String>[Flags.disableTypeInference];
    if (enableTypeAssertions) {
      options.add(Flags.enableCheckedMode);
    }
    if (minify) {
      options.add(Flags.minify);
    }
    if (analyzeAll) {
      options.add(Flags.analyzeAll);
    }
    if (trustJSInteropTypeAnnotations) {
      options.add(Flags.trustJSInteropTypeAnnotations);
    }
    if (compileMode == CompileMode.kernel) {
      options.add(Flags.useKernel);
    }

    if (disableInlining) {
      options.add(Flags.disableInlining);
    }

    Map<String, String> source;
    if (entry != 'main') {
      source = {'main.dart': "$code\n\nmain() => $entry;"};
    } else {
      source = {'main.dart': code};
    }

    CompilationResult result = await runCompiler(
        memorySourceFiles: source,
        options: options,
        outputProvider: outputCollector);
    Expect.isTrue(result.isSuccess);
    Compiler compiler = result.compiler;
    ClosedWorld closedWorld = compiler.backendClosedWorldForTesting;
    ElementEnvironment elementEnvironment = closedWorld.elementEnvironment;
    LibraryEntity mainLibrary = elementEnvironment.mainLibrary;
    FunctionEntity element =
        elementEnvironment.lookupLibraryMember(mainLibrary, entry);
    js.JavaScriptBackend backend = compiler.backend;
    String generated = backend.getGeneratedCode(element);
    if (check != null) {
      check(generated);
    }
    return returnAll ? outputCollector.getOutput('', OutputType.js) : generated;
  }
}

Future<String> compileAll(String code,
    {Map<String, String> coreSource,
    bool disableInlining: true,
    bool trustTypeAnnotations: false,
    bool minify: false,
    int expectedErrors,
    int expectedWarnings}) {
  Uri uri = new Uri(scheme: 'source');
  OutputCollector outputCollector = new OutputCollector();
  MockCompiler compiler = compilerFor(code, uri,
      coreSource: coreSource,
      disableInlining: disableInlining,
      minify: minify,
      expectedErrors: expectedErrors,
      trustTypeAnnotations: trustTypeAnnotations,
      expectedWarnings: expectedWarnings,
      outputProvider: outputCollector);
  compiler.diagnosticHandler = createHandler(compiler, code);
  return compiler.run(uri).then((compilationSucceded) {
    Expect.isTrue(
        compilationSucceded,
        'Unexpected compilation error(s): '
        '${compiler.diagnosticCollector.errors}');
    return outputCollector.getOutput('', OutputType.js);
  });
}

Future analyzeAndCheck(
    String code, String name, check(MockCompiler compiler, Element element),
    {int expectedErrors, int expectedWarnings}) {
  Uri uri = new Uri(scheme: 'source');
  MockCompiler compiler = compilerFor(code, uri,
      expectedErrors: expectedErrors,
      expectedWarnings: expectedWarnings,
      analyzeOnly: true);
  return compiler.run(uri).then((_) {
    Element element = findElement(compiler, name);
    return check(compiler, element);
  });
}

Future compileSources(
    Map<String, String> sources, check(MockCompiler compiler)) {
  Uri base = new Uri(scheme: 'source', path: '/');
  Uri mainUri = base.resolve('main.dart');
  String mainCode = sources['main.dart'];
  Expect.isNotNull(mainCode, 'No source code found for "main.dart"');
  MockCompiler compiler = compilerFor(mainCode, mainUri);
  sources.forEach((String path, String code) {
    if (path == 'main.dart') return;
    compiler.registerSource(base.resolve(path), code);
  });

  return compiler.run(mainUri).then((_) {
    return check(compiler);
  });
}

Element findElement(compiler, String name, [Uri library]) {
  LibraryElement lib = compiler.frontendStrategy.elementEnvironment.mainLibrary;
  if (library != null) {
    lib = compiler.libraryLoader.lookupLibrary(library);
    Expect.isNotNull(lib, 'Could not locate library $library.');
  }
  var element = lib.find(name);
  Expect.isNotNull(element, 'Could not locate $name.');
  return element;
}

String anyIdentifier = "[a-zA-Z][a-zA-Z0-9]*";

String getIntTypeCheck(String variable) {
  return "\\($variable ?!== ?\\($variable ?\\| ?0\\)|"
      "\\($variable ?>>> ?0 ?!== ?$variable";
}

String getNumberTypeCheck(String variable) {
  return """\\(typeof $variable ?!== ?"number"\\)""";
}

void checkNumberOfMatches(Iterator it, int nb) {
  bool hasNext = it.moveNext();
  for (int i = 0; i < nb; i++) {
    Expect.isTrue(hasNext, "Found less than $nb matches");
    hasNext = it.moveNext();
  }
  Expect.isFalse(hasNext, "Found more than $nb matches");
}

Future compileAndMatch(String code, String entry, RegExp regexp,
    {CompileMode compileMode: CompileMode.memory}) {
  return compile(code, entry: entry, compileMode: compileMode,
      check: (String generated) {
    Expect.isTrue(
        regexp.hasMatch(generated), '"$generated" does not match /$regexp/');
  });
}

Future compileAndDoNotMatch(String code, String entry, RegExp regexp,
    {CompileMode compileMode: CompileMode.memory}) {
  return compile(code, entry: entry, compileMode: compileMode,
      check: (String generated) {
    Expect.isFalse(
        regexp.hasMatch(generated), '"$generated" has a match in /$regexp/');
  });
}

int length(Link link) => link.isEmpty ? 0 : length(link.tail) + 1;

// Does a compile and then a match where every 'x' is replaced by something
// that matches any variable, and every space is optional.
Future compileAndMatchFuzzy(String code, String entry, String regexp) {
  return compileAndMatchFuzzyHelper(code, entry, regexp, true);
}

Future compileAndDoNotMatchFuzzy(String code, String entry, String regexp) {
  return compileAndMatchFuzzyHelper(code, entry, regexp, false);
}

Future compileAndMatchFuzzyHelper(
    String code, String entry, String regexp, bool shouldMatch) {
  return compile(code, entry: entry, check: (String generated) {
    final xRe = new RegExp('\\bx\\b');
    regexp = regexp.replaceAll(xRe, '(?:$anyIdentifier)');
    final spaceRe = new RegExp('\\s+');
    regexp = regexp.replaceAll(spaceRe, '(?:\\s*)');
    if (shouldMatch) {
      Expect.isTrue(new RegExp(regexp).hasMatch(generated));
    } else {
      Expect.isFalse(new RegExp(regexp).hasMatch(generated));
    }
  });
}

/// Returns a 'check' function that uses comments in [test] to drive checking.
///
/// The comments contains one or more 'present:' or 'absent:' tags, each
/// followed by a quoted string. For example, the returned checker for the
/// following text will ensure that the argument contains the three characters
/// 'foo' and does not contain the two characters '""':
///
///    // present: "foo"
///    // absent:  '""'
checkerForAbsentPresent(String test) {
  var matches = _directivePattern.allMatches(test).toList();
  checker(String generated) {
    if (matches.isEmpty) {
      Expect.fail("No 'absent:' or 'present:' directives in '$test'");
    }
    for (Match match in matches) {
      String directive = match.group(1);
      String pattern = match.groups([2, 3]).where((s) => s != null).single;
      if (directive == 'present') {
        Expect.isTrue(generated.contains(pattern),
            "Cannot find '$pattern' in:\n$generated");
      } else {
        assert(directive == 'absent');
        Expect.isFalse(generated.contains(pattern),
            "Must not find '$pattern' in:\n$generated");
      }
    }
  }

  return checker;
}

RegExp _directivePattern = new RegExp(
    //      \1                     \2        \3
    r'''// *(present|absent): *(?:"([^"]*)"|'([^'']*)')''', multiLine: true);