// Copyright (c) 2009 The Chromium Authors. All rights reserved.

// Use of this source code is governed by a BSD-style license that can be

// found in the LICENSE file.

package org.chromium.debug.ui.editors;

import org.eclipse.jface.text.rules.EndOfLineRule;

import org.eclipse.jface.text.rules.ICharacterScanner;

import org.eclipse.jface.text.rules.IPredicateRule;

import org.eclipse.jface.text.rules.IToken;

import org.eclipse.jface.text.rules.IWordDetector;

import org.eclipse.jface.text.rules.MultiLineRule;

import org.eclipse.jface.text.rules.RuleBasedPartitionScanner;

import org.eclipse.jface.text.rules.SingleLineRule;

import org.eclipse.jface.text.rules.Token;

import org.eclipse.jface.text.rules.WordRule;

/**

 * JavaScript partition scanner.

 */

public class JsPartitionScanner extends RuleBasedPartitionScanner {

  static final String PARTITIONING = "ChromiumJavaScriptPartitioning"; //$NON-NLS-1$

  static final String MULTILINE_COMMENT= "__js_multiline_comment"; //$NON-NLS-1$

  static final String JSDOC = "__jsdoc"; //$NON-NLS-1$

  static final String[] PARTITION_TYPES = {

    MULTILINE_COMMENT,

    JSDOC

  };

  /**

   * Empty comments should be handled so as not to be confused with JSDoc.

   */

  private static class EmptyCommentDetector implements IWordDetector {

    public boolean isWordStart(char c) {

      return (c == '/');

    }

    public boolean isWordPart(char c) {

      return (c == '*' || c == '/');

    }

  }

  private static class EmptyCommentPredicateRule extends WordRule implements IPredicateRule {

    private final IToken successToken;

    public EmptyCommentPredicateRule(IToken successToken) {

      super(new EmptyCommentDetector());

      this.successToken = successToken;

      addWord("/**/", successToken); //$NON-NLS-1$

    }

    public IToken evaluate(ICharacterScanner scanner, boolean resume) {

      return super.evaluate(scanner);

    }

    public IToken getSuccessToken() {

      return successToken;

    }

  }

  public JsPartitionScanner() {

    IToken jsDocToken= new Token(JSDOC);

    IToken multilineCommentToken= new Token(MULTILINE_COMMENT);

    setPredicateRules(new IPredicateRule[] {

        new EndOfLineRule("//", Token.UNDEFINED), //$NON-NLS-1$

        new SingleLineRule("\"", "\"", Token.UNDEFINED, '\\'), //$NON-NLS-2$ //$NON-NLS-1$

        new SingleLineRule("'", "'", Token.UNDEFINED, '\\'), //$NON-NLS-2$ //$NON-NLS-1$

        new EmptyCommentPredicateRule(multilineCommentToken),

        new MultiLineRule("/**", "*/", jsDocToken, (char) 0, true),  //$NON-NLS-1$ //$NON-NLS-2$

        new MultiLineRule("/*", "*/", multilineCommentToken, (char) 0, true) //$NON-NLS-1$ //$NON-NLS-2$

    });

  }

}