diff --git a/.github/workflows/dart-2-4.yml b/.github/workflows/dart-2-4.yml
new file mode 100644
index 0000000000..65b047df7d
--- /dev/null
+++ b/.github/workflows/dart-2-4.yml
@@ -0,0 +1,18 @@
+name: Dart 2.4
+
+on: [push]
+
+jobs:
+  build:
+
+    runs-on: ubuntu-latest
+
+    container:
+      image:  google/dart:2.4
+
+    steps:
+    - uses: actions/checkout@v1
+    - name: Install dependencies
+      run: pub get
+    - name: Run tests
+      run: pub run test
diff --git a/.github/workflows/dart-latest.yml b/.github/workflows/dart-latest.yml
new file mode 100644
index 0000000000..47b6c19f44
--- /dev/null
+++ b/.github/workflows/dart-latest.yml
@@ -0,0 +1,18 @@
+name: Dart latest
+
+on: [push]
+
+jobs:
+  build:
+
+    runs-on: ubuntu-latest
+
+    container:
+      image:  google/dart:latest
+
+    steps:
+    - uses: actions/checkout@v1
+    - name: Install dependencies
+      run: pub get
+    - name: Run tests
+      run: pub run test
diff --git a/CHANGELOG.md b/CHANGELOG.md
new file mode 100644
index 0000000000..c914039970
--- /dev/null
+++ b/CHANGELOG.md
@@ -0,0 +1,4 @@
+# Changelog
+
+## 1.0.0
+- Initial release
diff --git a/README.md b/README.md
index 0815b9bca6..2144de129c 100644
--- a/README.md
+++ b/README.md
@@ -1 +1,3 @@
-# dart-metrics
\ No newline at end of file
+# Dart metrics
+
+Command line tool which helps to improve code quality
diff --git a/analysis_options.yaml b/analysis_options.yaml
new file mode 100644
index 0000000000..ef3ba330d4
--- /dev/null
+++ b/analysis_options.yaml
@@ -0,0 +1,6 @@
+include: package:pedantic/analysis_options.yaml
+
+analyzer:
+  strong-mode:
+    implicit-casts: false
+    implicit-dynamic: false
diff --git a/bin/metrics.dart b/bin/metrics.dart
new file mode 100644
index 0000000000..0597a18fe6
--- /dev/null
+++ b/bin/metrics.dart
@@ -0,0 +1,88 @@
+import 'dart:io';
+
+import 'package:args/args.dart';
+import 'package:glob/glob.dart';
+import 'package:metrics/metrics_analyzer.dart';
+import 'package:metrics/reporters.dart';
+
+void main(List<String> args) {
+  const helpFlagName = 'help';
+  const reporterOptionName = 'reporter';
+  const cyclomaticComplexityThreshold = 'cyclomatic-complexity';
+  const linesOfCodeThreshold = 'lines-of-code';
+  const verboseName = 'verbose';
+  const ignoredFilesName = 'ignore-files';
+  const rootFolderName = 'root-folder';
+
+  var showUsage = false;
+
+  final parser = ArgParser()
+    ..addFlag(helpFlagName, abbr: 'h', help: 'Print this usage information.', negatable: false)
+    ..addOption(reporterOptionName,
+        abbr: 'r',
+        help: 'The format of the output of the analysis',
+        valueHelp: 'console',
+        allowed: ['console', 'json', 'html'],
+        defaultsTo: 'console')
+    ..addOption(cyclomaticComplexityThreshold,
+        help: 'Cyclomatic complexity threshold', valueHelp: '20', defaultsTo: '20')
+    ..addOption(linesOfCodeThreshold, help: 'Lines of code threshold', valueHelp: '50', defaultsTo: '50')
+    ..addOption(rootFolderName, help: 'Root folder', valueHelp: './', defaultsTo: Directory.current.path)
+    ..addOption(ignoredFilesName,
+        help: 'Filepaths in Glob syntax to be ignored',
+        valueHelp: '{/**.g.dart,/**.template.dart}',
+        defaultsTo: '{/**.g.dart,/**.template.dart}')
+    ..addFlag(verboseName, negatable: false);
+
+  ArgResults arguments;
+
+  try {
+    arguments = parser.parse(args);
+  } on FormatException catch (_) {
+    showUsage = true;
+  }
+
+  if (arguments[helpFlagName] as bool || arguments.rest.length != 1) {
+    showUsage = true;
+  }
+
+  if (showUsage) {
+    print('Usage: dartanalyzer [options...] <directory>');
+    print(parser.usage);
+    return;
+  }
+
+  final rootFolder = arguments[rootFolderName] as String;
+  var dartFilePaths = Glob('${arguments.rest.first}**.dart')
+      .listSync(root: rootFolder, followLinks: false)
+      .whereType<File>()
+      .map((entity) => entity.path);
+
+  final ignoreFilesPattern = arguments[ignoredFilesName] as Object;
+  if (ignoreFilesPattern is String && ignoreFilesPattern.isNotEmpty) {
+    final ignoreFilesGlob = Glob(ignoreFilesPattern);
+    dartFilePaths = dartFilePaths.where((path) => !ignoreFilesGlob.matches(path));
+  }
+
+  final recorder = MetricsAnalysisRecorder();
+  final analyzer = MetricsAnalyzer(recorder);
+  final runner = MetricsAnalysisRunner(recorder, analyzer, dartFilePaths, rootFolder: rootFolder)..run();
+
+  final config = Config(
+      cyclomaticComplexityWarningLevel: int.parse(arguments[cyclomaticComplexityThreshold] as String),
+      linesOfCodeWarningLevel: int.parse(arguments[linesOfCodeThreshold] as String));
+
+  switch (arguments[reporterOptionName] as String) {
+    case 'console':
+      ConsoleReporter(reportConfig: config, reportAll: arguments[verboseName] as bool).report(runner.results());
+      break;
+    case 'json':
+      JsonReporter(reportConfig: config).report(runner.results());
+      break;
+    case 'html':
+      HtmlReporter(reportConfig: config).report(runner.results());
+      break;
+    default:
+      throw ArgumentError.value(arguments[reporterOptionName], reporterOptionName);
+  }
+}
diff --git a/lib/metrics_analyzer.dart b/lib/metrics_analyzer.dart
new file mode 100644
index 0000000000..26a6d0a36f
--- /dev/null
+++ b/lib/metrics_analyzer.dart
@@ -0,0 +1,4 @@
+export 'package:metrics/src/metrics_analysis_recorder.dart';
+export 'package:metrics/src/metrics_analysis_runner.dart';
+export 'package:metrics/src/metrics_analyzer.dart';
+export 'package:metrics/src/models/config.dart';
diff --git a/lib/reporters.dart b/lib/reporters.dart
new file mode 100644
index 0000000000..cdb3322d88
--- /dev/null
+++ b/lib/reporters.dart
@@ -0,0 +1,4 @@
+export 'package:metrics/src/reporters/console_reporter.dart';
+export 'package:metrics/src/reporters/html_reporter.dart';
+export 'package:metrics/src/reporters/json_reporter.dart';
+export 'package:metrics/src/reporters/reporter.dart';
diff --git a/lib/src/cyclomatic_complexity/control_flow_ast_visitor.dart b/lib/src/cyclomatic_complexity/control_flow_ast_visitor.dart
new file mode 100644
index 0000000000..57ae65743c
--- /dev/null
+++ b/lib/src/cyclomatic_complexity/control_flow_ast_visitor.dart
@@ -0,0 +1,107 @@
+import 'package:analyzer/dart/ast/ast.dart';
+import 'package:analyzer/dart/ast/syntactic_entity.dart';
+import 'package:analyzer/dart/ast/token.dart';
+import 'package:analyzer/dart/ast/visitor.dart';
+import 'package:analyzer/source/line_info.dart';
+import 'package:metrics/src/cyclomatic_complexity/cyclomatic_config.dart';
+
+class ControlFlowAstVisitor extends RecursiveAstVisitor<Object> {
+  final CyclomaticConfig _config;
+  final LineInfo _lineInfo;
+
+  final _complexityLines = <int, int>{};
+
+  ControlFlowAstVisitor(this._config, this._lineInfo);
+
+  Map<int, int> get complexityLines => _complexityLines;
+
+  @override
+  void visitAssertStatement(AssertStatement node) {
+    _increaseComplexity('assertStatement', node);
+    super.visitAssertStatement(node);
+  }
+
+  @override
+  void visitBlockFunctionBody(BlockFunctionBody node) {
+    _collectFunctionBodyData(node.block.leftBracket.next, node.block.rightBracket);
+    super.visitBlockFunctionBody(node);
+  }
+
+  @override
+  void visitCatchClause(CatchClause node) {
+    _increaseComplexity('catchClause', node);
+    super.visitCatchClause(node);
+  }
+
+  @override
+  void visitConditionalExpression(ConditionalExpression node) {
+    _increaseComplexity('conditionalExpression', node);
+    super.visitConditionalExpression(node);
+  }
+
+  @override
+  void visitExpressionFunctionBody(ExpressionFunctionBody node) {
+    _collectFunctionBodyData(node.expression.beginToken.previous, node.expression.endToken.next);
+    node.visitChildren(this);
+  }
+
+  @override
+  void visitForStatement(ForStatement node) {
+    _increaseComplexity('forStatement', node);
+    super.visitForStatement(node);
+  }
+
+  @override
+  void visitIfStatement(IfStatement node) {
+    _increaseComplexity('ifStatement', node);
+    super.visitIfStatement(node);
+  }
+
+  @override
+  void visitSwitchCase(SwitchCase node) {
+    _increaseComplexity('switchCase', node);
+    super.visitSwitchCase(node);
+  }
+
+  @override
+  void visitSwitchDefault(SwitchDefault node) {
+    _increaseComplexity('switchDefault', node);
+    super.visitSwitchDefault(node);
+  }
+
+  @override
+  void visitWhileStatement(WhileStatement node) {
+    _increaseComplexity('whileStatement', node);
+    super.visitWhileStatement(node);
+  }
+
+  @override
+  void visitYieldStatement(YieldStatement node) {
+    _increaseComplexity('yieldStatement', node);
+    super.visitYieldStatement(node);
+  }
+
+  void _collectFunctionBodyData(Token firstToken, Token lastToken) {
+    const tokenTypes = [
+      TokenType.AMPERSAND_AMPERSAND,
+      TokenType.BAR_BAR,
+      TokenType.QUESTION_PERIOD,
+      TokenType.QUESTION_QUESTION,
+      TokenType.QUESTION_QUESTION_EQ
+    ];
+
+    var token = firstToken;
+    while (token != lastToken) {
+      if (token.matchesAny(tokenTypes)) {
+        _increaseComplexity('blockFunctionBody', token);
+      }
+      token = token.next;
+    }
+  }
+
+  void _increaseComplexity(String flowType, SyntacticEntity entity) {
+    final entityComplexity = _config.complexityByControlFlowType(flowType);
+    final entityLineNumber = _lineInfo.getLocation(entity.offset).lineNumber;
+    _complexityLines[entityLineNumber] = (_complexityLines[entityLineNumber] ?? 0) + entityComplexity;
+  }
+}
diff --git a/lib/src/cyclomatic_complexity/cyclomatic_config.dart b/lib/src/cyclomatic_complexity/cyclomatic_config.dart
new file mode 100644
index 0000000000..0b523337b6
--- /dev/null
+++ b/lib/src/cyclomatic_complexity/cyclomatic_config.dart
@@ -0,0 +1,34 @@
+import 'package:meta/meta.dart';
+
+@immutable
+class CyclomaticConfig {
+  static const Iterable<String> _options = [
+    'assertStatement',
+    'blockFunctionBody',
+    'catchClause',
+    'conditionalExpression',
+    'forEachStatement',
+    'forStatement',
+    'ifStatement',
+    'switchDefault',
+    'switchCase',
+    'whileStatement',
+    'yieldStatement',
+  ];
+
+  final Map<String, int> _addedComplexityByControlFlowType;
+
+  int complexityByControlFlowType(String type) {
+    if (!_options.contains(type)) {
+      throw ArgumentError.value(type);
+    }
+
+    return _addedComplexityByControlFlowType[type] ?? 0;
+  }
+
+  CyclomaticConfig({Iterable<int> complexity})
+      : _addedComplexityByControlFlowType =
+            Map<String, int>.fromIterables(_options, complexity ?? _options.map((_) => 1));
+}
+
+final CyclomaticConfig defaultCyclomaticConfig = CyclomaticConfig();
diff --git a/lib/src/cyclomatic_complexity/models/scoped_declaration.dart b/lib/src/cyclomatic_complexity/models/scoped_declaration.dart
new file mode 100644
index 0000000000..53a7dda18d
--- /dev/null
+++ b/lib/src/cyclomatic_complexity/models/scoped_declaration.dart
@@ -0,0 +1,10 @@
+import 'package:analyzer/dart/ast/ast.dart';
+import 'package:meta/meta.dart';
+
+@immutable
+class ScopedDeclaration {
+  final Declaration declaration;
+  final NamedCompilationUnitMember enclosingClass;
+
+  const ScopedDeclaration(this.declaration, this.enclosingClass);
+}
diff --git a/lib/src/halstead_volume/halstead_volume_ast_visitor.dart b/lib/src/halstead_volume/halstead_volume_ast_visitor.dart
new file mode 100644
index 0000000000..9d8321b1a2
--- /dev/null
+++ b/lib/src/halstead_volume/halstead_volume_ast_visitor.dart
@@ -0,0 +1,36 @@
+import 'package:analyzer/dart/ast/ast.dart';
+import 'package:analyzer/dart/ast/token.dart';
+import 'package:analyzer/dart/ast/visitor.dart';
+
+class HalsteadVolumeAstVisitor extends RecursiveAstVisitor<Object> {
+  final _operators = <String, int>{};
+  final _operands = <String, int>{};
+
+  Map<String, int> get operators => _operators;
+  Map<String, int> get operands => _operands;
+
+  @override
+  void visitBlockFunctionBody(BlockFunctionBody node) {
+    _analyzeFunctionBodyData(node.block.leftBracket.next, node.block.rightBracket);
+    super.visitBlockFunctionBody(node);
+  }
+
+  @override
+  void visitExpressionFunctionBody(ExpressionFunctionBody node) {
+    _analyzeFunctionBodyData(node.expression.beginToken.previous, node.expression.endToken.next);
+    node.visitChildren(this);
+  }
+
+  void _analyzeFunctionBodyData(Token firstToken, Token lastToken) {
+    var token = firstToken;
+    while (token != lastToken) {
+      if (token.isOperator) {
+        _operators[token.type.name] = (_operators[token.type.name] ?? 0) + 1;
+      }
+      if (token.isIdentifier) {
+        _operands[token.lexeme] = (_operands[token.lexeme] ?? 0) + 1;
+      }
+      token = token.next;
+    }
+  }
+}
diff --git a/lib/src/lines_of_code/function_body_ast_visitor.dart b/lib/src/lines_of_code/function_body_ast_visitor.dart
new file mode 100644
index 0000000000..55adc5e524
--- /dev/null
+++ b/lib/src/lines_of_code/function_body_ast_visitor.dart
@@ -0,0 +1,34 @@
+import 'package:analyzer/dart/ast/ast.dart';
+import 'package:analyzer/dart/ast/token.dart';
+import 'package:analyzer/dart/ast/visitor.dart';
+import 'package:analyzer/source/line_info.dart';
+
+class FunctionBodyAstVisitor extends RecursiveAstVisitor<Object> {
+  final LineInfo _lineInfo;
+
+  final _linesWithCode = <int>{};
+
+  FunctionBodyAstVisitor(this._lineInfo);
+
+  Iterable<int> get linesWithCode => _linesWithCode;
+
+  @override
+  void visitBlockFunctionBody(BlockFunctionBody node) {
+    _collectFunctionBodyData(node.block.leftBracket.next, node.block.rightBracket);
+    super.visitBlockFunctionBody(node);
+  }
+
+  @override
+  void visitExpressionFunctionBody(ExpressionFunctionBody node) {
+    _collectFunctionBodyData(node.expression.beginToken.previous, node.expression.endToken.next);
+    node.visitChildren(this);
+  }
+
+  void _collectFunctionBodyData(Token firstToken, Token lastToken) {
+    var token = firstToken;
+    while (token != lastToken) {
+      _linesWithCode.add(_lineInfo.getLocation(token.offset).lineNumber);
+      token = token.next;
+    }
+  }
+}
diff --git a/lib/src/metrics_analysis_recorder.dart b/lib/src/metrics_analysis_recorder.dart
new file mode 100644
index 0000000000..aae2a66492
--- /dev/null
+++ b/lib/src/metrics_analysis_recorder.dart
@@ -0,0 +1,46 @@
+import 'package:built_collection/built_collection.dart';
+import 'package:metrics/src/models/component_record.dart';
+import 'package:metrics/src/models/function_record.dart';
+import 'package:path/path.dart' as path;
+
+class MetricsAnalysisRecorder {
+  String _fileGroupPath;
+  String _relativeGroupPath;
+  Map<String, FunctionRecord> _groupRecords;
+
+  final _records = <ComponentRecord>[];
+  Iterable<ComponentRecord> records() => _records;
+
+  void startRecordFile(String filePath, String rootDirectory) {
+    if (filePath == null) {
+      throw ArgumentError.notNull('filePath');
+    }
+    if (_fileGroupPath != null) {
+      throw StateError(
+          "Can't start a file group while another one is started. Use `endRecordFile` to close the opened one.");
+    }
+
+    _fileGroupPath = filePath;
+    _relativeGroupPath = rootDirectory != null ? path.relative(filePath, from: rootDirectory) : filePath;
+    _groupRecords = {};
+  }
+
+  void endRecordFile() {
+    _records.add(ComponentRecord(
+        fullPath: _fileGroupPath, relativePath: _relativeGroupPath, records: BuiltMap.from(_groupRecords)));
+    _relativeGroupPath = null;
+    _fileGroupPath = null;
+    _groupRecords = null;
+  }
+
+  void record(String recordName, FunctionRecord report) {
+    if (recordName == null) {
+      throw ArgumentError.notNull('recordName');
+    }
+    if (_groupRecords == null) {
+      throw StateError('No record groups have been started. Use `startRecordFile` before `record`');
+    }
+
+    _groupRecords[recordName] = report;
+  }
+}
diff --git a/lib/src/metrics_analysis_runner.dart b/lib/src/metrics_analysis_runner.dart
new file mode 100644
index 0000000000..59ebf8cd33
--- /dev/null
+++ b/lib/src/metrics_analysis_runner.dart
@@ -0,0 +1,21 @@
+import 'package:metrics/src/metrics_analysis_recorder.dart';
+import 'package:metrics/src/metrics_analyzer.dart';
+import 'package:metrics/src/models/component_record.dart';
+
+class MetricsAnalysisRunner {
+  final MetricsAnalysisRecorder _recorder;
+  final MetricsAnalyzer _analyzer;
+  final Iterable<String> _filePaths;
+  final String _rootFolder;
+
+  MetricsAnalysisRunner(this._recorder, this._analyzer, this._filePaths, {String rootFolder})
+      : _rootFolder = rootFolder;
+
+  Iterable<ComponentRecord> results() => _recorder.records();
+
+  void run() {
+    for (final file in _filePaths) {
+      _analyzer.runAnalysis(file, _rootFolder);
+    }
+  }
+}
diff --git a/lib/src/metrics_analyzer.dart b/lib/src/metrics_analyzer.dart
new file mode 100644
index 0000000000..e819d586cf
--- /dev/null
+++ b/lib/src/metrics_analyzer.dart
@@ -0,0 +1,61 @@
+import 'package:analyzer/analyzer.dart';
+import 'package:analyzer/dart/ast/ast.dart';
+import 'package:built_collection/built_collection.dart';
+import 'package:metrics/src/cyclomatic_complexity/control_flow_ast_visitor.dart';
+import 'package:metrics/src/cyclomatic_complexity/cyclomatic_config.dart';
+import 'package:metrics/src/cyclomatic_complexity/models/scoped_declaration.dart';
+import 'package:metrics/src/halstead_volume/halstead_volume_ast_visitor.dart';
+import 'package:metrics/src/lines_of_code/function_body_ast_visitor.dart';
+import 'package:metrics/src/metrics_analysis_recorder.dart';
+import 'package:metrics/src/models/function_record.dart';
+import 'package:metrics/src/scope_ast_visitor.dart';
+
+String getQualifiedName(ScopedDeclaration dec) {
+  final declaration = dec.declaration;
+
+  if (declaration is FunctionDeclaration) {
+    return declaration.name.toString();
+  } else if (declaration is MethodDeclaration) {
+    return '${dec.enclosingClass.name}.${declaration.name}';
+  }
+
+  return null;
+}
+
+class MetricsAnalyzer {
+  final MetricsAnalysisRecorder _recorder;
+
+  MetricsAnalyzer(this._recorder);
+
+  void runAnalysis(String filePath, String rootFolder) {
+    final visitor = ScopeAstVisitor();
+    final compilationUnit = parseDartFile(filePath, suppressErrors: true)..visitChildren(visitor);
+    if (visitor.declarations.isNotEmpty) {
+      _recorder.startRecordFile(filePath, rootFolder);
+
+      for (final scopedDeclaration in visitor.declarations) {
+        final controlFlowAstVisitor = ControlFlowAstVisitor(defaultCyclomaticConfig, compilationUnit.lineInfo);
+        final functionBodyAstVisitor = FunctionBodyAstVisitor(compilationUnit.lineInfo);
+        final halsteadVolumeAstVisitor = HalsteadVolumeAstVisitor();
+
+        scopedDeclaration.declaration.visitChildren(controlFlowAstVisitor);
+        scopedDeclaration.declaration.visitChildren(functionBodyAstVisitor);
+        scopedDeclaration.declaration.visitChildren(halsteadVolumeAstVisitor);
+
+        _recorder.record(
+            getQualifiedName(scopedDeclaration),
+            FunctionRecord(
+                firstLine: compilationUnit.lineInfo
+                    .getLocation(scopedDeclaration.declaration.firstTokenAfterCommentAndMetadata.offset)
+                    .lineNumber,
+                lastLine: compilationUnit.lineInfo.getLocation(scopedDeclaration.declaration.endToken.end).lineNumber,
+                cyclomaticLinesComplexity: BuiltMap.from(controlFlowAstVisitor.complexityLines),
+                linesWithCode: functionBodyAstVisitor.linesWithCode,
+                operators: BuiltMap.from(halsteadVolumeAstVisitor.operators),
+                operands: BuiltMap.from(halsteadVolumeAstVisitor.operands)));
+      }
+
+      _recorder.endRecordFile();
+    }
+  }
+}
diff --git a/lib/src/models/component_record.dart b/lib/src/models/component_record.dart
new file mode 100644
index 0000000000..238cc1c7cb
--- /dev/null
+++ b/lib/src/models/component_record.dart
@@ -0,0 +1,13 @@
+import 'package:built_collection/built_collection.dart';
+import 'package:meta/meta.dart';
+import 'package:metrics/src/models/function_record.dart';
+
+@immutable
+class ComponentRecord {
+  final String fullPath;
+  final String relativePath;
+
+  final BuiltMap<String, FunctionRecord> records;
+
+  const ComponentRecord({@required this.fullPath, @required this.relativePath, @required this.records});
+}
diff --git a/lib/src/models/component_report.dart b/lib/src/models/component_report.dart
new file mode 100644
index 0000000000..bfbebf3900
--- /dev/null
+++ b/lib/src/models/component_report.dart
@@ -0,0 +1,21 @@
+import 'package:meta/meta.dart';
+
+@immutable
+class ComponentReport {
+  final double averageMaintainabilityIndex;
+  final int totalMaintainabilityIndexViolations;
+
+  final int totalCyclomaticComplexity;
+  final int totalCyclomaticComplexityViolations;
+
+  final int totalLinesOfCode;
+  final int totalLinesOfCodeViolations;
+
+  const ComponentReport(
+      {@required this.averageMaintainabilityIndex,
+      @required this.totalMaintainabilityIndexViolations,
+      @required this.totalCyclomaticComplexity,
+      @required this.totalCyclomaticComplexityViolations,
+      @required this.totalLinesOfCode,
+      @required this.totalLinesOfCodeViolations});
+}
diff --git a/lib/src/models/config.dart b/lib/src/models/config.dart
new file mode 100644
index 0000000000..f809bc306a
--- /dev/null
+++ b/lib/src/models/config.dart
@@ -0,0 +1,9 @@
+import 'package:meta/meta.dart';
+
+@immutable
+class Config {
+  final int cyclomaticComplexityWarningLevel;
+  final int linesOfCodeWarningLevel;
+
+  const Config({@required this.cyclomaticComplexityWarningLevel, @required this.linesOfCodeWarningLevel});
+}
diff --git a/lib/src/models/function_record.dart b/lib/src/models/function_record.dart
new file mode 100644
index 0000000000..e5740d2aeb
--- /dev/null
+++ b/lib/src/models/function_record.dart
@@ -0,0 +1,23 @@
+import 'package:built_collection/built_collection.dart';
+import 'package:meta/meta.dart';
+
+@immutable
+class FunctionRecord {
+  final int firstLine;
+  final int lastLine;
+
+  final BuiltMap<int, int> cyclomaticLinesComplexity;
+
+  final Iterable<int> linesWithCode;
+
+  final BuiltMap<String, int> operators;
+  final BuiltMap<String, int> operands;
+
+  const FunctionRecord(
+      {@required this.firstLine,
+      @required this.lastLine,
+      @required this.cyclomaticLinesComplexity,
+      @required this.linesWithCode,
+      @required this.operators,
+      @required this.operands});
+}
diff --git a/lib/src/models/function_report.dart b/lib/src/models/function_report.dart
new file mode 100644
index 0000000000..14ccb3bd42
--- /dev/null
+++ b/lib/src/models/function_report.dart
@@ -0,0 +1,22 @@
+import 'package:meta/meta.dart';
+import 'package:metrics/src/models/violation_level.dart';
+
+@immutable
+class FunctionReport {
+  final int cyclomaticComplexity;
+  final ViolationLevel cyclomaticComplexityViolationLevel;
+
+  final int linesOfCode;
+  final ViolationLevel linesOfCodeViolationLevel;
+
+  final double maintainabilityIndex;
+  final ViolationLevel maintainabilityIndexViolationLevel;
+
+  const FunctionReport(
+      {@required this.cyclomaticComplexity,
+      @required this.cyclomaticComplexityViolationLevel,
+      @required this.linesOfCode,
+      @required this.linesOfCodeViolationLevel,
+      @required this.maintainabilityIndex,
+      @required this.maintainabilityIndexViolationLevel});
+}
diff --git a/lib/src/models/violation_level.dart b/lib/src/models/violation_level.dart
new file mode 100644
index 0000000000..e9c784670c
--- /dev/null
+++ b/lib/src/models/violation_level.dart
@@ -0,0 +1,20 @@
+class ViolationLevel {
+  static const ViolationLevel none = ViolationLevel._('None');
+  static const ViolationLevel noted = ViolationLevel._('Noted');
+  static const ViolationLevel warning = ViolationLevel._('Warning');
+  static const ViolationLevel alarm = ViolationLevel._('Alarm');
+
+  static const Iterable<ViolationLevel> values = [
+    ViolationLevel.none,
+    ViolationLevel.noted,
+    ViolationLevel.warning,
+    ViolationLevel.alarm
+  ];
+
+  final String _name;
+
+  const ViolationLevel._(this._name);
+
+  @override
+  String toString() => _name;
+}
diff --git a/lib/src/reporters/console_reporter.dart b/lib/src/reporters/console_reporter.dart
new file mode 100644
index 0000000000..39a6ff88f1
--- /dev/null
+++ b/lib/src/reporters/console_reporter.dart
@@ -0,0 +1,75 @@
+import 'package:ansicolor/ansicolor.dart';
+import 'package:meta/meta.dart';
+import 'package:metrics/src/models/component_record.dart';
+import 'package:metrics/src/models/config.dart';
+import 'package:metrics/src/models/violation_level.dart';
+import 'package:metrics/src/reporters/reporter.dart';
+import 'package:metrics/src/reporters/utility_selector.dart';
+
+class ConsoleReporter implements Reporter {
+  final Config reportConfig;
+  final bool reportAll;
+
+  final _redPen = AnsiPen()..red();
+  final _yellowPen = AnsiPen()..yellow();
+  final _bluePen = AnsiPen()..blue();
+
+  ConsoleReporter({@required this.reportConfig, this.reportAll = false});
+
+  @override
+  void report(Iterable<ComponentRecord> records) {
+    if (records?.isEmpty ?? true) {
+      return;
+    }
+
+    for (final analysisRecord in records) {
+      final lines = <String>[];
+
+      analysisRecord.records.forEach((source, functionReport) {
+        final report = UtilitySelector.functionReport(functionReport, reportConfig);
+
+        switch (report.cyclomaticComplexityViolationLevel) {
+          case ViolationLevel.alarm:
+            lines.add('${_redPen('ALARM')}   $source - complexity: ${_redPen('${report.cyclomaticComplexity}')}');
+            break;
+          case ViolationLevel.warning:
+            lines.add('${_yellowPen('WARNING')} $source - complexity: ${_yellowPen('${report.cyclomaticComplexity}')}');
+            break;
+          case ViolationLevel.noted:
+            lines.add('${_bluePen('NOTED')}   $source - complexity: ${_yellowPen('${report.cyclomaticComplexity}')}');
+            break;
+          case ViolationLevel.none:
+            if (reportAll) {
+              lines.add('        $source - complexity: ${report.cyclomaticComplexity}');
+            }
+            break;
+        }
+      });
+
+      if (lines.isNotEmpty || reportAll) {
+        final report = UtilitySelector.analysisReport(analysisRecord, reportConfig);
+
+        var consoleRecord = analysisRecord.relativePath;
+        consoleRecord += ' - complexity: ${report.totalCyclomaticComplexity}';
+        if (report.totalCyclomaticComplexityViolations > 0) {
+          consoleRecord += '  complexity violations: ${_yellowPen('${report.totalCyclomaticComplexityViolations}')}';
+        }
+        consoleRecord += '  lines of code: ${report.totalLinesOfCode}';
+
+        print(consoleRecord);
+        lines.forEach(print);
+        print('');
+      }
+    }
+
+    final report = UtilitySelector.analysisReportForRecords(records, reportConfig);
+
+    var packageTotalRecord = 'Total complexity: ${report.totalCyclomaticComplexity}';
+    if (report.totalCyclomaticComplexityViolations > 0) {
+      packageTotalRecord += '  complexity violations: ${_yellowPen('${report.totalCyclomaticComplexityViolations}')}';
+    }
+    packageTotalRecord += '  lines of code: ${report.totalLinesOfCode}';
+
+    print(packageTotalRecord);
+  }
+}
diff --git a/lib/src/reporters/html_reporter.dart b/lib/src/reporters/html_reporter.dart
new file mode 100644
index 0000000000..0aa8a3516f
--- /dev/null
+++ b/lib/src/reporters/html_reporter.dart
@@ -0,0 +1,421 @@
+import 'dart:convert';
+import 'dart:io';
+
+import 'package:html/dom.dart';
+import 'package:meta/meta.dart';
+import 'package:metrics/src/models/component_record.dart';
+import 'package:metrics/src/models/config.dart';
+import 'package:metrics/src/models/violation_level.dart';
+import 'package:metrics/src/reporters/reporter.dart';
+import 'package:metrics/src/reporters/utility_selector.dart';
+import 'package:path/path.dart' as path;
+import 'package:resource/resource.dart';
+
+const _violationLevelFunctionStyle = {
+  ViolationLevel.alarm: 'metrics-source-code__text--attention-complexity',
+  ViolationLevel.warning: 'metrics-source-code__text--warning-complexity',
+  ViolationLevel.noted: 'metrics-source-code__text--noted-complexity',
+  ViolationLevel.none: 'metrics-source-code__text--normal-complexity',
+};
+
+const _violationLevelLineStyle = {
+  ViolationLevel.alarm: 'metrics-source-code__line--attention-complexity',
+  ViolationLevel.warning: 'metrics-source-code__line--warning-complexity',
+  ViolationLevel.noted: 'metrics-source-code__line--noted-complexity',
+  ViolationLevel.none: 'metrics-source-code__line--normal-complexity',
+};
+
+const _cyclomaticComplexity = 'Cyclomatic complexity';
+const _cyclomaticComplexityWithViolations = 'Cyclomatic complexity / violations';
+const _linesOfCode = 'Lines of code';
+const _linesOfCodeWithViolations = 'Lines of code / violations';
+const _maintainabilityIndex = 'Maintainability index';
+const _maintainabilityIndexWithViolations = 'Maintainability index / violations';
+
+@immutable
+class ReportTableRecord {
+  final String title;
+  final String link;
+
+  final int cyclomaticComplexity;
+  final int cyclomaticComplexityViolations;
+
+  final int linesOfCode;
+  final int linesOfCodeViolations;
+
+  final double maintainabilityIndex;
+  final int maintainabilityIndexViolations;
+
+  const ReportTableRecord(
+      {@required this.title,
+      @required this.link,
+      @required this.cyclomaticComplexity,
+      @required this.cyclomaticComplexityViolations,
+      @required this.linesOfCode,
+      @required this.linesOfCodeViolations,
+      @required this.maintainabilityIndex,
+      @required this.maintainabilityIndexViolations});
+}
+
+class HtmlReporter implements Reporter {
+  final Config reportConfig;
+  final String reportFolder;
+
+  HtmlReporter({this.reportConfig, this.reportFolder = 'metrics'});
+
+  @override
+  void report(Iterable<ComponentRecord> records) {
+    if (records?.isEmpty ?? true) {
+      return;
+    }
+
+    _createReportDirectory(reportFolder);
+    _copyResources(reportFolder);
+    for (final record in records) {
+      _generateSourceReport(reportFolder, record);
+    }
+    _generateFoldersReports(reportFolder, records);
+  }
+
+  void _createReportDirectory(String directoryName) {
+    final reportDirectory = Directory(directoryName);
+    if (reportDirectory.existsSync()) {
+      reportDirectory.deleteSync(recursive: true);
+    }
+    reportDirectory.createSync(recursive: true);
+  }
+
+  void _copyResources(String reportFolder) {
+    const baseStylesheet = 'base';
+
+    const res = Resource('package:metrics/src/reporters/html_resources/base.css');
+    res.readAsString().then((content) {
+      File(path.setExtension(path.join(reportFolder, baseStylesheet), '.css'))
+        ..createSync(recursive: true)
+        ..writeAsStringSync(content);
+    });
+  }
+
+  Element _generateTable(String title, Iterable<ReportTableRecord> records) {
+    final sortedRecords = records.toList()..sort((a, b) => a.title.compareTo(b.title));
+
+    final totalComplexity = sortedRecords.fold<int>(0, (prevValue, record) => prevValue + record.cyclomaticComplexity);
+    final totalComplexityViolations =
+        sortedRecords.fold<int>(0, (prevValue, record) => prevValue + record.cyclomaticComplexityViolations);
+    final totalLinesOfCode = sortedRecords.fold<int>(0, (prevValue, record) => prevValue + record.linesOfCode);
+    final totalLinesOfCodeViolations =
+        sortedRecords.fold<int>(0, (prevValue, record) => prevValue + record.linesOfCodeViolations);
+    final averageMaintainabilityIndex =
+        sortedRecords.fold<double>(0, (prevValue, record) => prevValue + record.maintainabilityIndex) /
+            sortedRecords.length;
+    final totalMaintainabilityIndexViolations =
+        sortedRecords.fold<int>(0, (prevValue, record) => prevValue + record.maintainabilityIndexViolations);
+
+    final withCyclomaticComplexityViolations = totalComplexityViolations > 0;
+    final withLinesOfCodeViolations = totalLinesOfCodeViolations > 0;
+    final withMaintainabilityIndexViolations = totalMaintainabilityIndexViolations > 0;
+
+    final tableContent = Element.tag('tbody');
+    for (final record in sortedRecords) {
+      final recordHaveCyclomaticComplexityViolations = record.cyclomaticComplexityViolations > 0;
+      final recordHaveLinesOfCodeViolations = record.linesOfCodeViolations > 0;
+      final recordHaveMaintainabilityIndexViolations = record.maintainabilityIndexViolations > 0;
+
+      tableContent.append(Element.tag('tr')
+        ..append(Element.tag('td')
+          ..append(Element.tag('a')
+            ..attributes['href'] = record.link
+            ..text = record.title))
+        ..append(Element.tag('td')
+          ..text = recordHaveCyclomaticComplexityViolations
+              ? '${record.cyclomaticComplexity} / ${record.cyclomaticComplexityViolations}'
+              : '${record.cyclomaticComplexity}'
+          ..classes.add(recordHaveCyclomaticComplexityViolations ? 'with-violations' : ''))
+        ..append(Element.tag('td')
+          ..text = recordHaveLinesOfCodeViolations
+              ? '${record.linesOfCode} / ${record.linesOfCodeViolations}'
+              : '${record.linesOfCode}'
+          ..classes.add(recordHaveLinesOfCodeViolations ? 'with-violations' : ''))
+        ..append(Element.tag('td')
+          ..text = recordHaveMaintainabilityIndexViolations
+              ? '${record.maintainabilityIndex.toInt()} / ${record.maintainabilityIndexViolations}'
+              : '${record.maintainabilityIndex.toInt()}'
+          ..classes.add(recordHaveMaintainabilityIndexViolations ? 'with-violations' : '')));
+    }
+
+    final cyclomaticComplexityTitle =
+        withCyclomaticComplexityViolations ? _cyclomaticComplexityWithViolations : _cyclomaticComplexity;
+    final linesOfCodeTitle = withLinesOfCodeViolations ? _linesOfCodeWithViolations : _linesOfCode;
+    final maintainabilityIndexTitle =
+        withMaintainabilityIndexViolations ? _maintainabilityIndexWithViolations : _maintainabilityIndex;
+
+    final table = Element.tag('table')
+      ..classes.add('metrics-total-table')
+      ..append(Element.tag('thead')
+        ..append(Element.tag('tr')
+          ..append(Element.tag('th')..text = title)
+          ..append(Element.tag('th')..text = cyclomaticComplexityTitle)
+          ..append(Element.tag('th')..text = linesOfCodeTitle)
+          ..append(Element.tag('th')..text = maintainabilityIndexTitle)))
+      ..append(tableContent);
+
+    return Element.tag('div')
+      ..classes.add('metric-wrapper')
+      ..append(table)
+      ..append(Element.tag('div')
+        ..classes.add('metrics-totals')
+        ..append(_generateTotalMetrics(
+            cyclomaticComplexityTitle,
+            withCyclomaticComplexityViolations ? '$totalComplexity / $totalComplexityViolations' : '$totalComplexity',
+            withCyclomaticComplexityViolations))
+        ..append(_generateTotalMetrics(
+            linesOfCodeTitle,
+            withLinesOfCodeViolations ? '$totalLinesOfCode / $totalLinesOfCodeViolations' : '$totalLinesOfCode',
+            withLinesOfCodeViolations))
+        ..append(_generateTotalMetrics(
+            maintainabilityIndexTitle,
+            withMaintainabilityIndexViolations
+                ? '${averageMaintainabilityIndex.toInt()} / $totalMaintainabilityIndexViolations'
+                : '${averageMaintainabilityIndex.toInt()}',
+            withMaintainabilityIndexViolations)));
+  }
+
+  void _generateFoldersReports(String reportDirectory, Iterable<ComponentRecord> records) {
+    final folders = records.map((record) => path.dirname(record.relativePath)).toSet();
+
+    for (final folder in folders) {
+      _generateFolderReport(
+          reportDirectory, folder, records.where((record) => path.dirname(record.relativePath) == folder));
+    }
+
+    final tableRecords = folders.map((folder) {
+      final report = UtilitySelector.analysisReportForRecords(
+          records.where((record) => path.dirname(record.relativePath) == folder), reportConfig);
+      return ReportTableRecord(
+          title: folder,
+          link: path.join(folder, 'index.html'),
+          cyclomaticComplexity: report.totalCyclomaticComplexity,
+          cyclomaticComplexityViolations: report.totalCyclomaticComplexityViolations,
+          linesOfCode: report.totalLinesOfCode,
+          linesOfCodeViolations: report.totalLinesOfCodeViolations,
+          maintainabilityIndex: report.averageMaintainabilityIndex,
+          maintainabilityIndexViolations: report.totalMaintainabilityIndexViolations);
+    });
+
+    final html = Element.tag('html')
+      ..attributes['lang'] = 'en'
+      ..append(Element.tag('head')
+        ..append(Element.tag('title')..text = 'Metrics report')
+        ..append(Element.tag('meta')..attributes['charset'] = 'utf-8')
+        ..append(Element.tag('link')
+          ..attributes['rel'] = 'stylesheet'
+          ..attributes['href'] = 'base.css'))
+      ..append(Element.tag('body')
+        ..append(Element.tag('h1')
+          ..classes.add('metric-header')
+          ..text = 'All files')
+        ..append(_generateTable('Directory', tableRecords)));
+
+    final htmlDocument = Document()..append(html);
+
+    File(path.join(reportDirectory, 'index.html'))
+      ..createSync(recursive: true)
+      ..writeAsStringSync(htmlDocument.outerHtml.replaceAll('&amp;nbsp;', '&nbsp;'));
+  }
+
+  void _generateFolderReport(String reportDirectory, String folder, Iterable<ComponentRecord> records) {
+    final tableRecords = records.map((record) {
+      final report = UtilitySelector.analysisReport(record, reportConfig);
+      final fileName = path.basename(record.relativePath);
+
+      return ReportTableRecord(
+          title: fileName,
+          link: path.setExtension(fileName, '.html'),
+          cyclomaticComplexity: report.totalCyclomaticComplexity,
+          cyclomaticComplexityViolations: report.totalCyclomaticComplexityViolations,
+          linesOfCode: report.totalLinesOfCode,
+          linesOfCodeViolations: report.totalLinesOfCodeViolations,
+          maintainabilityIndex: report.averageMaintainabilityIndex,
+          maintainabilityIndexViolations: report.totalMaintainabilityIndexViolations);
+    });
+
+    final html = Element.tag('html')
+      ..attributes['lang'] = 'en'
+      ..append(Element.tag('head')
+        ..append(Element.tag('title')..text = 'Metrics report for $folder')
+        ..append(Element.tag('meta')..attributes['charset'] = 'utf-8')
+        ..append(Element.tag('link')
+          ..attributes['rel'] = 'stylesheet'
+          ..attributes['href'] = path.relative('base.css', from: folder)))
+      ..append(Element.tag('body')
+        ..append(Element.tag('h1')
+          ..classes.add('metric-header')
+          ..append(Element.tag('a')
+            ..attributes['href'] = path.relative('index.html', from: folder)
+            ..text = 'All files')
+          ..append(Element.tag('span')..text = ' : ')
+          ..append(Element.tag('span')..text = folder))
+        ..append(_generateTable('File', tableRecords)));
+
+    final htmlDocument = Document()..append(html);
+
+    File(path.join(reportDirectory, folder, 'index.html'))
+      ..createSync(recursive: true)
+      ..writeAsStringSync(htmlDocument.outerHtml.replaceAll('&amp;nbsp;', '&nbsp;'));
+  }
+
+  void _generateSourceReport(String reportDirectory, ComponentRecord record) {
+    final sourceFileContent = File(record.fullPath).readAsStringSync();
+    final sourceFileLines = LineSplitter.split(sourceFileContent);
+
+    final linesIndices = Element.tag('td')..classes.add('metrics-source-code__number-lines');
+    for (var i = 1; i <= sourceFileLines.length; ++i) {
+      linesIndices
+        ..append(Element.tag('a')..attributes['name'] = 'L$i')
+        ..append(Element.tag('a')
+          ..attributes['href'] = '#L$i'
+          ..text = '$i')
+        ..append(Element.tag('br'));
+    }
+
+    final cyclomaticValues = Element.tag('td')..classes.add('metrics-source-code__complexity');
+    for (var i = 1; i <= sourceFileLines.length; ++i) {
+      final functionReport = record.records.values.firstWhere(
+          (functionReport) => functionReport.firstLine <= i && functionReport.lastLine >= i,
+          orElse: () => null);
+
+      final complexityValueElement = Element.tag('div')..classes.add('metrics-source-code__text');
+
+      var line = ' ';
+      if (functionReport != null) {
+        final report = UtilitySelector.functionReport(functionReport, reportConfig);
+
+        if (functionReport.firstLine == i) {
+          line = 'ⓘ';
+
+          complexityValueElement.attributes['class'] =
+              '${complexityValueElement.attributes['class']} metrics-source-code__text--with-icon'.trim();
+
+          complexityValueElement.attributes['title'] = 'Function stats:'
+              '\n${_cyclomaticComplexity.toLowerCase()}: ${report.cyclomaticComplexity}'
+              '\n${_cyclomaticComplexity.toLowerCase()} violation level: ${report.cyclomaticComplexityViolationLevel.toString().toLowerCase()}'
+              '\n${_linesOfCode.toLowerCase()}: ${report.linesOfCode}'
+              '\n${_linesOfCode.toLowerCase()} violation level: ${report.linesOfCodeViolationLevel.toString().toLowerCase()}'
+              '\n${_maintainabilityIndex.toLowerCase()}: ${report.maintainabilityIndex.toInt()}'
+              '\n${_maintainabilityIndex.toLowerCase()} violation level: ${report.maintainabilityIndexViolationLevel.toString().toLowerCase()}';
+        }
+
+        final lineWithComplexityIncrement = functionReport.cyclomaticLinesComplexity.containsKey(i);
+        if (lineWithComplexityIncrement) {
+          line = '$line +${functionReport.cyclomaticLinesComplexity[i]}'.trim();
+        }
+
+/*      uncomment this block if you need check lines with code
+        final lineWithCode = functionReport.linesWithCode.contains(i);
+        if (lineWithCode) {
+          line += ' c';
+        }
+*/
+        final functionViolationLevel = UtilitySelector.functionViolationLevel(report);
+
+        final lineViolationStyle = lineWithComplexityIncrement
+            ? _violationLevelLineStyle[functionViolationLevel]
+            : _violationLevelFunctionStyle[functionViolationLevel];
+
+        complexityValueElement.classes.add(lineViolationStyle ?? '');
+      }
+      complexityValueElement.text = line.replaceAll(' ', '&nbsp;');
+
+      cyclomaticValues.append(complexityValueElement);
+    }
+
+    final codeBlock = Element.tag('td')
+      ..classes.add('metrics-source-code__code')
+      ..append(Element.tag('pre')
+        ..classes.add('prettyprint lang-dart')
+        ..text = sourceFileContent);
+
+    final report = UtilitySelector.analysisReport(record, reportConfig);
+
+    final withCyclomaticComplexityViolations = report.totalCyclomaticComplexityViolations > 0;
+    final withLinesOfCodeViolations = report.totalLinesOfCodeViolations > 0;
+    final totalMaintainabilityIndexViolations = report.totalMaintainabilityIndexViolations > 0;
+
+    final body = Element.tag('body')
+      ..append(Element.tag('h1')
+        ..classes.add('metric-header')
+        ..append(Element.tag('a')
+          ..attributes['href'] = path.relative('index.html', from: path.dirname(record.relativePath))
+          ..text = 'All files')
+        ..append(Element.tag('span')..text = ' : ')
+        ..append(Element.tag('a')
+          ..attributes['href'] = 'index.html'
+          ..text = path.dirname(record.relativePath))
+        ..append(Element.tag('span')..text = '/${path.basename(record.relativePath)}'))
+      ..append(_generateTotalMetrics(
+          withCyclomaticComplexityViolations ? _cyclomaticComplexityWithViolations : _cyclomaticComplexity,
+          withCyclomaticComplexityViolations
+              ? '${report.totalCyclomaticComplexity} / ${report.totalCyclomaticComplexityViolations}'
+              : '${report.totalCyclomaticComplexity}',
+          withCyclomaticComplexityViolations))
+      ..append(_generateTotalMetrics(
+          withLinesOfCodeViolations ? _linesOfCodeWithViolations : _linesOfCode,
+          withLinesOfCodeViolations
+              ? '${report.totalLinesOfCode} / ${report.totalLinesOfCodeViolations}'
+              : '${report.totalLinesOfCode}',
+          withLinesOfCodeViolations))
+      ..append(_generateTotalMetrics(
+          totalMaintainabilityIndexViolations ? _maintainabilityIndexWithViolations : _maintainabilityIndex,
+          totalMaintainabilityIndexViolations
+              ? '${report.averageMaintainabilityIndex.toInt()} / ${report.totalMaintainabilityIndexViolations}'
+              : '${report.averageMaintainabilityIndex.toInt()}',
+          totalMaintainabilityIndexViolations))
+      ..append(Element.tag('pre')
+        ..append(Element.tag('table')
+          ..classes.add('metrics-source-code')
+          ..append(Element.tag('thead')
+            ..classes.add('metrics-source-code__header')
+            ..append(Element.tag('tr')
+              ..append(Element.tag('td')..classes.add('metrics-source-code__number-lines'))
+              ..append(Element.tag('td')
+                ..classes.add('metrics-source-code__complexity')
+                ..text = 'Complexity')
+              ..append(Element.tag('td')
+                ..classes.add('metrics-source-code__code')
+                ..text = 'Source code')))
+          ..append(Element.tag('tbody')
+            ..classes.add('metrics-source-code__body')
+            ..append(Element.tag('tr')..append(linesIndices)..append(cyclomaticValues)..append(codeBlock)))))
+      ..append(Element.tag('script')
+        ..attributes['src'] = 'https://cdn.jsdelivr.net/gh/google/code-prettify@master/loader/run_prettify.min.js')
+      ..append(Element.tag('script')
+        ..attributes['src'] = 'https://cdn.jsdelivr.net/gh/google/code-prettify@master/loader/lang-dart.min.js');
+
+    final head = Element.tag('head')
+      ..append(Element.tag('title')..text = 'Metrics report for ${record.relativePath}')
+      ..append(Element.tag('meta')..attributes['charset'] = 'utf-8')
+      ..append(Element.tag('link')
+        ..attributes['rel'] = 'stylesheet'
+        ..attributes['href'] = path.relative('base.css', from: path.dirname(record.relativePath)));
+
+    final html = Element.tag('html')
+      ..attributes['lang'] = 'en'
+      ..append(head)
+      ..append(body);
+
+    final htmlDocument = Document()..append(html);
+
+    File(path.setExtension(path.join(reportDirectory, record.relativePath), '.html'))
+      ..createSync(recursive: true)
+      ..writeAsStringSync(htmlDocument.outerHtml.replaceAll('&amp;nbsp;', '&nbsp;'));
+  }
+
+  Element _generateTotalMetrics(String name, String value, bool violations) => Element.tag('div')
+    ..classes.add(!violations ? 'metrics-total' : 'metrics-total metrics-total--violations')
+    ..append(Element.tag('span')
+      ..classes.add('metrics-total__label')
+      ..text = '$name : ')
+    ..append(Element.tag('span')
+      ..classes.add('metrics-total__count')
+      ..text = value);
+}
diff --git a/lib/src/reporters/html_resources/base.css b/lib/src/reporters/html_resources/base.css
new file mode 100644
index 0000000000..fcdb45af7f
--- /dev/null
+++ b/lib/src/reporters/html_resources/base.css
@@ -0,0 +1,312 @@
+/* Start ============== NORMALIZE =============== */
+
+/*! based on normalize.css v5.0.0 | MIT License | github.com/necolas */
+
+/*
+* 1. Change the default font family in all browsers (opinionated).
+* 2. Prevent adjustments of font size after orientation changes in
+*    IE on Windows Phone and in iOS.
+*/
+
+/* Document ========================================================================== */
+
+html {
+  font-family: sans-serif; /* 1 */
+  -ms-text-size-adjust: 100%; /* 2 */
+  -webkit-text-size-adjust: 100%; /* 2 */
+}
+
+/* Sections ========================================================================== */
+
+/*
+* Remove the margin in all browsers (opinionated).
+*/
+body {
+  margin: 0;
+}
+
+h1,
+h2,
+h3,
+h4,
+h5,
+h6 {
+  margin: 0;
+}
+
+p {
+  margin: 0;
+}
+
+/* Grouping content ========================================================================== */
+
+/*
+* 1. Add the correct box sizing in Firefox.
+* 2. Show the overflow in Edge and IE.
+*/
+hr {
+  box-sizing: content-box; /* 1 */
+  height: 0; /* 1 */
+  overflow: visible; /* 2 */
+}
+
+/* Text-level semantics ========================================================================== */
+
+/*
+* Remove gaps in links underline in iOS 8+ and Safari 8+.
+*/
+a {
+  -webkit-text-decoration-skip: objects;
+  outline: none;
+}
+
+/*
+* Remove the outline on focused links when they are also active or hovered
+* in all browsers (opinionated).
+*/
+a:active,
+a:hover {
+  outline-width: 0;
+}
+
+/*
+* Prevent text blurriness in Firefox on macOS
+* link: https://stackoverflow.com/a/44898465
+*/
+@supports (-moz-appearance: meterbar) and (background-blend-mode: difference, normal) {
+
+  body {
+    -moz-osx-font-smoothing: grayscale;
+  }
+}
+
+/* ============== NORMALIZE =============== End */
+
+/* Start ============== BASE =============== */
+
+*,
+*::before,
+*::after {
+  box-sizing: border-box;
+}
+
+body {
+  padding: 24px;
+  font-family: "Open sans", "Lucida grande", "Segoe UI", Arial, Verdana, Tahoma, sans-serif;
+  font-size: 14px;
+}
+
+table {
+  width: 100%;
+  margin: 0;
+  border-spacing: 0;
+  font-size: inherit;
+}
+
+table td {
+  vertical-align: top;
+}
+
+pre,
+code {
+  margin: 0;
+  font-family: "Courier New", monospace;
+  font-size: 1em;
+}
+
+/* ============== BASE =============== END */
+
+/* Start ============== CUSTOM =============== */
+a {
+  text-decoration: none;
+  color: #4488ff;
+}
+
+a:hover {
+  opacity: .7;
+}
+
+.metric-header {
+  margin-bottom: 24px;
+  font-size: 18px;
+}
+
+.metric-wrapper {
+  display: flex;
+  justify-content: space-between;
+}
+
+.metrics-total-table {
+  width: calc(100% - 360px);
+  border-top: 1px solid rgba(0,0,0,0.32);
+  border-left: 1px solid rgba(0,0,0,0.32);
+}
+
+.metrics-total-table th,
+.metrics-total-table td {
+  padding: 8px;
+  border-right: 1px solid rgba(0,0,0,0.32);
+}
+
+.metrics-total-table td {
+  border-bottom: 1px solid rgba(0,0,0,0.32);
+}
+
+.metrics-total-table th {
+  border-bottom: 2px solid rgba(0,0,0,0.32);
+}
+
+.metrics-total-table tr th:first-child,
+.metrics-total-table tr td:first-child {
+  text-align: left;
+  min-width: 128px;
+}
+
+.metrics-total-table tr td {
+  word-break: break-all;
+}
+
+.metrics-total-table tr th:not(:first-child) {
+  width: 128px;
+}
+
+.metrics-total-table tr td:not(:first-child) {
+  text-align: center;
+}
+
+.metrics-totals {
+  width: 352px;
+}
+
+.metrics-total {
+  padding: 8px 12px;
+  background-color: rgba(106, 200, 236, 0.35);
+}
+
+.metrics-total--violations,
+.with-violations {
+  background-color: rgba(252, 142, 0, 0.35);
+}
+
+.metrics-total + .metrics-total {
+  margin-top: 8px;
+}
+
+.metrics-total__count {
+  font-weight: bold;
+}
+
+.metrics-source-code {
+  margin-top: 24px;
+  border: 1px solid #ccc;
+}
+
+.metrics-source-code__header td {
+  padding: 8px;
+  font-family: "Open sans", "Lucida grande", "Segoe UI", Arial, Verdana, Tahoma, sans-serif;
+  font-weight: 800;
+  font-size: 12px;
+  letter-spacing: .083em;
+  text-transform: uppercase;
+  border-bottom: 1px solid #ccc;
+}
+
+.metrics-source-code__number-lines {
+  width: 48px;
+  border-right: 1px solid #ccc;
+  text-align: right
+}
+
+.metrics-source-code__number-lines a {
+  padding: 0 4px;
+  text-decoration: none;
+  color: #4488ff;
+}
+
+.metrics-source-code__number-lines a:hover {
+  color: #2fd5d9;
+}
+
+.metrics-source-code__number-lines a:focus-within {
+  background-color: #4488ff;
+  color: #fff;
+}
+
+.metrics-source-code__body .metrics-source-code__number-lines {
+  padding: 8px 4px;
+}
+
+.metrics-source-code__complexity {
+  width: 112px;
+  padding: 8px 0;
+  border-right: 1px solid #ccc;
+}
+
+pre.prettyprint.prettyprint {
+  border: 0;
+  padding: 0;
+  text-overflow: ellipsis;
+  overflow: hidden;
+}
+
+.metrics-source-code__text {
+  padding: 0 8px;
+}
+
+.metrics-source-code__text::after {
+  content: "";
+  position: absolute;
+  left: calc(112px + 48px + 16px + 8px);
+  width: calc(100% - 112px - 48px - 16px - 32px);
+  height: 16px;
+  background-color: inherit;
+  z-index: -1;
+}
+
+.metrics-source-code__code {
+  position: relative;
+  padding: 8px;
+  line-height: 16px;
+}
+
+.metrics-source-code__line--normal-complexity {
+  background-color: #33bb1159;
+}
+
+.metrics-source-code__line--noted-complexity {
+  background-color: #59c5ff59;
+}
+
+.metrics-source-code__line--warning-complexity {
+  background-color: #fc8e0059;
+}
+
+.metrics-source-code__line--attention-complexity {
+  background-color: #f1586659;
+}
+
+.metrics-source-code__text--normal-complexity {
+  background-color: #33bb1126;
+}
+
+.metrics-source-code__text--noted-complexity {
+  background-color: #59c5ff26;
+}
+
+.metrics-source-code__text--warning-complexity {
+  background-color: #fc8e0026;
+}
+
+.metrics-source-code__text--attention-complexity {
+  background-color: #f1586626;
+}
+
+.metrics-source-code__text--with-icon {
+  display: flex;
+  align-items: center;
+  height: 16px;
+  font-size: 12px;
+}
+
+/* ============== CUSTOM =============== END */
+
diff --git a/lib/src/reporters/json_reporter.dart b/lib/src/reporters/json_reporter.dart
new file mode 100644
index 0000000000..b6ec9856c9
--- /dev/null
+++ b/lib/src/reporters/json_reporter.dart
@@ -0,0 +1,34 @@
+import 'dart:convert';
+
+import 'package:meta/meta.dart';
+import 'package:metrics/src/models/component_record.dart';
+import 'package:metrics/src/models/config.dart';
+import 'package:metrics/src/reporters/reporter.dart';
+import 'package:metrics/src/reporters/utility_selector.dart';
+
+class JsonReporter implements Reporter {
+  final Config reportConfig;
+
+  JsonReporter({@required this.reportConfig});
+
+  @override
+  void report(Iterable<ComponentRecord> records) {
+    if (records?.isEmpty ?? true) {
+      return;
+    }
+
+    print(json.encode(records.map(_analysisRecordToJson).toList()));
+  }
+
+  Map<String, Object> _analysisRecordToJson(ComponentRecord record) => {
+        'source': record.relativePath,
+        'records': record.records.asMap().map((key, value) {
+          final report = UtilitySelector.functionReport(value, reportConfig);
+          return MapEntry(key, {
+            'cyclomatic-complexity': report.cyclomaticComplexity,
+            'cyclomatic-complexity-violation-level': report.cyclomaticComplexityViolationLevel.toString().toLowerCase(),
+            'lines-of-code': report.linesOfCode,
+          });
+        })
+      };
+}
diff --git a/lib/src/reporters/reporter.dart b/lib/src/reporters/reporter.dart
new file mode 100644
index 0000000000..2a09e27ecf
--- /dev/null
+++ b/lib/src/reporters/reporter.dart
@@ -0,0 +1,6 @@
+import 'package:metrics/src/models/component_record.dart';
+
+// ignore: one_member_abstracts
+abstract class Reporter {
+  void report(Iterable<ComponentRecord> records);
+}
diff --git a/lib/src/reporters/utility_selector.dart b/lib/src/reporters/utility_selector.dart
new file mode 100644
index 0000000000..dffcc90368
--- /dev/null
+++ b/lib/src/reporters/utility_selector.dart
@@ -0,0 +1,163 @@
+import 'dart:math';
+
+import 'package:metrics/src/models/component_record.dart';
+import 'package:metrics/src/models/component_report.dart';
+import 'package:metrics/src/models/config.dart';
+import 'package:metrics/src/models/function_record.dart';
+import 'package:metrics/src/models/function_report.dart';
+import 'package:metrics/src/models/violation_level.dart';
+
+double log2(num a) => log(a) / ln2;
+
+class UtilitySelector {
+  static ComponentReport analysisReportForRecords(Iterable<ComponentRecord> records, Config config) {
+    final report = records.fold<ComponentReport>(
+        const ComponentReport(
+            averageMaintainabilityIndex: 0,
+            totalMaintainabilityIndexViolations: 0,
+            totalCyclomaticComplexity: 0,
+            totalCyclomaticComplexityViolations: 0,
+            totalLinesOfCode: 0,
+            totalLinesOfCodeViolations: 0), (prevValue, record) {
+      final report = analysisReport(record, config);
+
+      return ComponentReport(
+          averageMaintainabilityIndex: prevValue.averageMaintainabilityIndex + report.averageMaintainabilityIndex,
+          totalMaintainabilityIndexViolations:
+              prevValue.totalMaintainabilityIndexViolations + report.totalMaintainabilityIndexViolations,
+          totalCyclomaticComplexity: prevValue.totalCyclomaticComplexity + report.totalCyclomaticComplexity,
+          totalCyclomaticComplexityViolations:
+              prevValue.totalCyclomaticComplexityViolations + report.totalCyclomaticComplexityViolations,
+          totalLinesOfCode: prevValue.totalLinesOfCode + report.totalLinesOfCode,
+          totalLinesOfCodeViolations: prevValue.totalLinesOfCodeViolations + report.totalLinesOfCodeViolations);
+    });
+
+    return ComponentReport(
+        averageMaintainabilityIndex: report.averageMaintainabilityIndex / records.length,
+        totalMaintainabilityIndexViolations: report.totalMaintainabilityIndexViolations,
+        totalCyclomaticComplexity: report.totalCyclomaticComplexity,
+        totalCyclomaticComplexityViolations: report.totalCyclomaticComplexityViolations,
+        totalLinesOfCode: report.totalLinesOfCode,
+        totalLinesOfCodeViolations: report.totalLinesOfCodeViolations);
+  }
+
+  static ComponentReport analysisReport(ComponentRecord record, Config config) {
+    var averageMaintainabilityIndex = 0.0;
+    var totalMaintainabilityIndexViolations = 0;
+    var totalCyclomaticComplexity = 0;
+    var totalCyclomaticComplexityViolations = 0;
+    var totalLinesOfCode = 0;
+    var totalLinesOfCodeViolations = 0;
+
+    for (final record in record.records.values) {
+      final report = functionReport(record, config);
+
+      averageMaintainabilityIndex += report.maintainabilityIndex;
+      if (report.maintainabilityIndexViolationLevel == ViolationLevel.warning ||
+          report.maintainabilityIndexViolationLevel == ViolationLevel.alarm) {
+        ++totalMaintainabilityIndexViolations;
+      }
+
+      totalCyclomaticComplexity += report.cyclomaticComplexity;
+      if (report.cyclomaticComplexity >= config.cyclomaticComplexityWarningLevel) {
+        ++totalCyclomaticComplexityViolations;
+      }
+
+      totalLinesOfCode += report.linesOfCode;
+      if (report.linesOfCode >= config.linesOfCodeWarningLevel) {
+        ++totalLinesOfCodeViolations;
+      }
+    }
+
+    return ComponentReport(
+        averageMaintainabilityIndex: averageMaintainabilityIndex / record.records.values.length,
+        totalMaintainabilityIndexViolations: totalMaintainabilityIndexViolations,
+        totalCyclomaticComplexity: totalCyclomaticComplexity,
+        totalCyclomaticComplexityViolations: totalCyclomaticComplexityViolations,
+        totalLinesOfCode: totalLinesOfCode,
+        totalLinesOfCodeViolations: totalLinesOfCodeViolations);
+  }
+
+  static FunctionReport functionReport(FunctionRecord function, Config config) {
+    final cyclomaticComplexity =
+        function.cyclomaticLinesComplexity.values.fold<int>(0, (prevValue, nextValue) => prevValue + nextValue) + 1;
+
+    final linesOfCode = function.linesWithCode.length;
+
+    // Total number of occurrences of operators.
+    final totalNumberOfOccurrencesOfOperators =
+        function.operators.values.fold<int>(0, (prevValue, nextValue) => prevValue + nextValue);
+
+    // Total number of occurrences of operands
+    final totalNumberOfOccurrencesOfOperands =
+        function.operands.values.fold<int>(0, (prevValue, nextValue) => prevValue + nextValue);
+
+    // Number of distinct operators.
+    final numberOfDistinctOperators = function.operators.keys.length;
+
+    // Number of distinct operands.
+    final numberOfDistinctOperands = function.operands.keys.length;
+
+    // Halstead Program Length – The total number of operator occurrences and the total number of operand occurrences.
+    final halsteadProgramLength = totalNumberOfOccurrencesOfOperators + totalNumberOfOccurrencesOfOperands;
+
+    // Halstead Vocabulary – The total number of unique operator and unique operand occurrences.
+    final halsteadVocabulary = numberOfDistinctOperators + numberOfDistinctOperands;
+
+    // Program Volume – Proportional to program size, represents the size, in bits, of space necessary for storing the program. This parameter is dependent on specific algorithm implementation.
+    final halsteadVolume = halsteadProgramLength * log2(max(1, halsteadVocabulary));
+
+    final maintainabilityIndex = max(
+            0,
+            (171 - 5.2 * log(max(1, halsteadVolume)) - 0.23 * cyclomaticComplexity - 16.2 * log(max(1, linesOfCode))) *
+                100 /
+                171)
+        .toDouble();
+
+    return FunctionReport(
+        cyclomaticComplexity: cyclomaticComplexity,
+        cyclomaticComplexityViolationLevel:
+            _violationLevel(cyclomaticComplexity, config.cyclomaticComplexityWarningLevel),
+        linesOfCode: linesOfCode,
+        linesOfCodeViolationLevel: _violationLevel(linesOfCode, config.linesOfCodeWarningLevel),
+        maintainabilityIndex: maintainabilityIndex,
+        maintainabilityIndexViolationLevel: _maintainabilityIndexViolationLevel(maintainabilityIndex));
+  }
+
+  static ViolationLevel functionViolationLevel(FunctionReport report) {
+    final values = ViolationLevel.values.toList();
+
+    final cyclomaticComplexityViolationLevelIndex = values.indexOf(report.cyclomaticComplexityViolationLevel);
+    final linesOfCodeViolationLevelIndex = values.indexOf(report.linesOfCodeViolationLevel);
+    final maintainabilityIndexViolationLevelIndex = values.indexOf(report.maintainabilityIndexViolationLevel);
+
+    final highestLevelIndex = max(max(cyclomaticComplexityViolationLevelIndex, linesOfCodeViolationLevelIndex),
+        maintainabilityIndexViolationLevelIndex);
+
+    return values.elementAt(highestLevelIndex);
+  }
+
+  static ViolationLevel _violationLevel(int value, int warningLevel) {
+    if (value >= warningLevel * 2) {
+      return ViolationLevel.alarm;
+    } else if (value >= warningLevel) {
+      return ViolationLevel.warning;
+    } else if (value >= (warningLevel / 2).floor()) {
+      return ViolationLevel.noted;
+    }
+
+    return ViolationLevel.none;
+  }
+
+  static ViolationLevel _maintainabilityIndexViolationLevel(double index) {
+    if (index < 10) {
+      return ViolationLevel.alarm;
+    } else if (index < 20) {
+      return ViolationLevel.warning;
+    } else if (index < 40) {
+      return ViolationLevel.noted;
+    }
+
+    return ViolationLevel.none;
+  }
+}
diff --git a/lib/src/scope_ast_visitor.dart b/lib/src/scope_ast_visitor.dart
new file mode 100644
index 0000000000..b7fb6baa24
--- /dev/null
+++ b/lib/src/scope_ast_visitor.dart
@@ -0,0 +1,43 @@
+import 'package:analyzer/dart/ast/ast.dart';
+import 'package:analyzer/dart/ast/visitor.dart';
+import 'package:metrics/src/cyclomatic_complexity/models/scoped_declaration.dart';
+
+class ScopeAstVisitor extends RecursiveAstVisitor<Object> {
+  final _declarations = <ScopedDeclaration>[];
+
+  ClassOrMixinDeclaration _enclosingClass;
+
+  Iterable<ScopedDeclaration> get declarations => _declarations;
+
+  @override
+  void visitClassDeclaration(ClassDeclaration node) {
+    _enclosingClass = node;
+    super.visitClassDeclaration(node);
+    _enclosingClass = null;
+  }
+
+  @override
+  void visitFunctionDeclaration(FunctionDeclaration node) {
+    _registerDeclaration(node);
+    super.visitFunctionDeclaration(node);
+  }
+
+  @override
+  void visitMethodDeclaration(MethodDeclaration node) {
+    if (node.body is! EmptyFunctionBody) {
+      _registerDeclaration(node);
+    }
+    super.visitMethodDeclaration(node);
+  }
+
+  @override
+  void visitMixinDeclaration(MixinDeclaration node) {
+    _enclosingClass = node;
+    super.visitMixinDeclaration(node);
+    _enclosingClass = null;
+  }
+
+  void _registerDeclaration(Declaration node) {
+    _declarations.add(ScopedDeclaration(node, _enclosingClass));
+  }
+}
diff --git a/pubspec.yaml b/pubspec.yaml
new file mode 100644
index 0000000000..18192dbd23
--- /dev/null
+++ b/pubspec.yaml
@@ -0,0 +1,27 @@
+name: metrics
+description: Command line tool which helps to improve code quality
+version: 1.0.0
+homepage: https://github.com/wrike/metrics
+author: Dmitry Krutskih <dmitry.krutskikh@team.wrike.com>
+
+environment:
+  sdk: ">=2.4.0 <3.0.0"
+
+dependencies:
+  analyzer: '>=0.38.0 <0.39.0'
+  ansicolor: ^1.0.0
+  args: ^1.5.0
+  built_collection: ^4.2.0
+  glob: ^1.2.0
+  html: '>=0.13.0 < 1.0.0'
+  intl: ^0.15.2
+  meta: ^1.1.0
+  path: ^1.6.0
+  resource: ^2.1.0
+
+dev_dependencies:
+  pedantic: ^1.9.0
+  test: ^1.9.0
+
+executables:
+  metrics:
diff --git a/test/scope_ast_visitor_test.dart b/test/scope_ast_visitor_test.dart
new file mode 100644
index 0000000000..7ee94814a0
--- /dev/null
+++ b/test/scope_ast_visitor_test.dart
@@ -0,0 +1,23 @@
+@TestOn('vm')
+import 'package:analyzer/analyzer.dart';
+import 'package:metrics/src/scope_ast_visitor.dart';
+import 'package:test/test.dart';
+
+void main() {
+  group('analyze file with ', () {
+    test('abstract class', () {
+      final visitor = ScopeAstVisitor();
+      parseDartFile('./test/scope_ast_visitor_test/sample_abstract_class.dart').visitChildren(visitor);
+
+      expect(visitor.declarations, isEmpty);
+    });
+    test('mixin', () {
+      final visitor = ScopeAstVisitor();
+      parseDartFile('./test/scope_ast_visitor_test/sample_mixin.dart').visitChildren(visitor);
+
+      expect(visitor.declarations.length, equals(1));
+      expect(visitor.declarations.first.declaration, isNotNull);
+      expect(visitor.declarations.first.enclosingClass, isNotNull);
+    });
+  });
+}
diff --git a/test/scope_ast_visitor_test/sample_abstract_class.dart b/test/scope_ast_visitor_test/sample_abstract_class.dart
new file mode 100644
index 0000000000..88265bd98a
--- /dev/null
+++ b/test/scope_ast_visitor_test/sample_abstract_class.dart
@@ -0,0 +1,5 @@
+abstract class Foo {
+  void bar1(Iterable<String> records);
+
+  void bar2(Iterable<int> records);
+}
diff --git a/test/scope_ast_visitor_test/sample_mixin.dart b/test/scope_ast_visitor_test/sample_mixin.dart
new file mode 100644
index 0000000000..8d055cd816
--- /dev/null
+++ b/test/scope_ast_visitor_test/sample_mixin.dart
@@ -0,0 +1,3 @@
+mixin ValuesMapping<K, V> {
+  V findValueByKey(Map<K, V> map, K key) => map[key];
+}