xml/xml-psi-impl/src/com/intellij/lexer/HtmlLexer.java

/*
 * Copyright 2000-2013 JetBrains s.r.o.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.intellij.lexer;

import com.intellij.lang.HtmlInlineScriptTokenTypesProvider;
import com.intellij.lang.Language;
import com.intellij.lang.LanguageHtmlInlineScriptTokenTypesProvider;
import com.intellij.lang.LanguageUtil;
import com.intellij.openapi.extensions.Extensions;
import com.intellij.psi.TokenType;
import com.intellij.psi.tree.IElementType;
import com.intellij.psi.xml.XmlTokenType;
import org.jetbrains.annotations.NotNull;

/**
 * @author Maxim.Mossienko
 */
public class HtmlLexer extends BaseHtmlLexer {
  private static IElementType ourStyleElementType;
  private static IElementType ourInlineStyleElementType;
  private static IElementType ourInlineScriptElementType;

  static {
    HtmlEmbeddedTokenTypesProvider[] extensions = Extensions.getExtensions(HtmlEmbeddedTokenTypesProvider.EXTENSION_POINT_NAME);
    for (HtmlEmbeddedTokenTypesProvider extension : extensions) {
      if ("style".equals(extension.getName())) {
        ourStyleElementType = extension.getElementType();
        ourInlineStyleElementType = extension.getInlineElementType();
      }
    }
    // At the moment only JS.
    HtmlInlineScriptTokenTypesProvider provider =
      LanguageHtmlInlineScriptTokenTypesProvider.getInlineScriptProvider(ourDefaultLanguage);
    ourInlineScriptElementType = provider != null ? provider.getElementType() : null;
  }

  private IElementType myTokenType;
  private int myTokenStart;
  private int myTokenEnd;

  @Override
  public void start(@NotNull CharSequence buffer, int startOffset, int endOffset, int initialState) {
    myTokenType = null;
    super.start(buffer, startOffset, endOffset, initialState);
  }

  public void advance() {
    myTokenType = null;
    super.advance();
  }

  public IElementType getTokenType() {
    if (myTokenType!=null) return myTokenType;
    IElementType tokenType = super.getTokenType();

    myTokenStart = super.getTokenStart();
    myTokenEnd = super.getTokenEnd();

    if (hasSeenStyle()) {
      if (hasSeenTag() && ourStyleElementType!=null && isStartOfEmbeddmentTagContent(tokenType)) {
        myTokenEnd = skipToTheEndOfTheEmbeddment();
        tokenType = ourStyleElementType;
      } else if (ourInlineStyleElementType!=null && isStartOfEmbeddmentAttributeValue(tokenType) && hasSeenAttribute()) {
        tokenType = ourInlineStyleElementType;
      }
    } else if (hasSeenScript()) {
      Language scriptLanguage = getScriptLanguage();
      boolean canInject = scriptLanguage == null || LanguageUtil.isInjectableLanguage(scriptLanguage);
      if (hasSeenTag() && isStartOfEmbeddmentTagContent(tokenType) && canInject) {
        myTokenEnd = skipToTheEndOfTheEmbeddment();
        IElementType currentScriptElementType = getCurrentScriptElementType();
        tokenType = currentScriptElementType == null ? XmlTokenType.XML_DATA_CHARACTERS : currentScriptElementType;
      } else if (hasSeenAttribute() && isStartOfEmbeddmentAttributeValue(tokenType) && ourInlineScriptElementType!=null) {
        myTokenEnd = skipToTheEndOfTheEmbeddment();
        tokenType = ourInlineScriptElementType;
      }
    }

    return myTokenType = tokenType;
  }

  private static boolean isStartOfEmbeddmentAttributeValue(final IElementType tokenType) {
    return tokenType == XmlTokenType.XML_ATTRIBUTE_VALUE_TOKEN;
  }

  private static boolean isStartOfEmbeddmentTagContent(final IElementType tokenType) {
    return (tokenType == XmlTokenType.XML_DATA_CHARACTERS ||
            tokenType == XmlTokenType.XML_CDATA_START ||
            tokenType == XmlTokenType.XML_COMMENT_START ||
            tokenType == XmlTokenType.XML_REAL_WHITE_SPACE || tokenType == TokenType.WHITE_SPACE
    );
  }

  public HtmlLexer() {
    this(new MergingLexerAdapter(new FlexAdapter(new _HtmlLexer()), TOKENS_TO_MERGE),true);
  }

  protected HtmlLexer(Lexer _baseLexer, boolean _caseInsensitive) {
    super(_baseLexer,_caseInsensitive);
  }

  protected boolean isHtmlTagState(int state) {
    return state == _HtmlLexer.START_TAG_NAME || state == _HtmlLexer.END_TAG_NAME;
  }

  public int getTokenStart() {
    if (myTokenType!=null) {
      return myTokenStart;
    }
    return super.getTokenStart();
  }

  public int getTokenEnd() {
    if (myTokenType!=null) {
      return myTokenEnd;
    }
    return super.getTokenEnd();
  }
}