// 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.

/** Common definitions used for setting up the test environment. */
library testing;

import 'package:csslib/parser.dart';
import 'package:csslib/visitor.dart';
import 'package:csslib/src/messages.dart';

void useMockMessages() {
  messages = new Messages(printHandler: (message) {});
}

/**
 * Spin-up CSS parser in checked mode to detect any problematic CSS.  Normally,
 * CSS will allow any property/value pairs regardless of validity; all of our
 * tests (by default) will ensure that the CSS is really valid.
 */
StyleSheet parseCss(String cssInput, {List errors, List opts}) =>
  parse(cssInput, errors: errors, options: opts == null ?
      ['--no-colors', '--checked', '--warnings_as_errors', 'memory'] : opts);

/**
 * Spin-up CSS parser in checked mode to detect any problematic CSS.  Normally,
 * CSS will allow any property/value pairs regardless of validity; all of our
 * tests (by default) will ensure that the CSS is really valid.
 */
StyleSheet compileCss(String cssInput, {List errors, List opts,
    bool polyfill: false, List<StyleSheet> includes: null}) =>
  compile(cssInput, errors: errors, options: opts == null ?
      ['--no-colors', '--checked', '--warnings_as_errors', 'memory'] : opts,
      polyfill: polyfill, includes: includes);

StyleSheet polyFillCompileCss(input, {List errors, List opts}) =>
    compileCss(input, errors: errors, polyfill: true, opts: opts);

/** CSS emitter walks the style sheet tree and emits readable CSS. */
final _emitCss = new CssPrinter();

/** Simple Visitor does nothing but walk tree. */
final _cssVisitor = new Visitor();

/** Pretty printer for CSS. */
String prettyPrint(StyleSheet ss) {
  // Walk the tree testing basic Vistor class.
  walkTree(ss);
  return (_emitCss..visitTree(ss, pretty: true)).toString();
}

/**
 * Helper function to emit compact (non-pretty printed) CSS for suite test
 * comparsions.  Spaces, new lines, etc. are reduced for easier comparsions of
 * expected suite test results.
 */
String compactOuptut(StyleSheet ss) {
  walkTree(ss);
  return (_emitCss..visitTree(ss, pretty: false)).toString();
}

/** Walks the style sheet tree does nothing; insures the basic walker works. */
void walkTree(StyleSheet ss) {
  _cssVisitor..visitTree(ss);
}

String dumpTree(StyleSheet ss) => treeToDebugString(ss);