/*
 * Copyright 2013 The authors
 * 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.struts2.jsp;

import com.intellij.lang.injection.MultiHostInjector;
import com.intellij.lang.injection.MultiHostRegistrar;
import com.intellij.openapi.fileTypes.FileType;
import com.intellij.openapi.fileTypes.StdFileTypes;
import com.intellij.openapi.project.DumbAware;
import com.intellij.openapi.util.TextRange;
import com.intellij.patterns.ElementPattern;
import com.intellij.psi.PsiElement;
import com.intellij.psi.PsiLanguageInjectionHost;
import com.intellij.psi.css.CssFileType;
import com.intellij.psi.xml.XmlAttributeValue;
import com.intellij.struts2.StrutsConstants;
import org.jetbrains.annotations.NotNull;

import java.util.Collections;
import java.util.List;

import static com.intellij.patterns.XmlPatterns.xmlAttributeValue;
import static com.intellij.patterns.XmlPatterns.xmlTag;

/**
 * Adds CSS inline support for UI/jQuery-plugin tags in JSP(X).
 *
 * @author Yann Cébron
 */
public class TaglibCssInlineStyleInjector implements MultiHostInjector, DumbAware {

  private static final ElementPattern<XmlAttributeValue> CSS_ELEMENT_PATTERN =
    xmlAttributeValue()
      .withSuperParent(2, xmlTag().withNamespace(StrutsConstants.TAGLIB_STRUTS_UI_URI,
                                                 StrutsConstants.TAGLIB_JQUERY_PLUGIN_URI,
                                                 StrutsConstants.TAGLIB_JQUERY_RICHTEXT_PLUGIN_URI,
                                                 StrutsConstants.TAGLIB_JQUERY_CHART_PLUGIN_URI,
                                                 StrutsConstants.TAGLIB_JQUERY_TREE_PLUGIN_URI,
                                                 StrutsConstants.TAGLIB_JQUERY_GRID_PLUGIN_URI,
                                                 StrutsConstants.TAGLIB_JQUERY_MOBILE_PLUGIN_URI,
                                                 StrutsConstants.TAGLIB_BOOTSTRAP_PLUGIN_URI
      ))
      .withLocalName(StrutsConstants.TAGLIB_STRUTS_UI_CSS_ATTRIBUTES);

  public void getLanguagesToInject(@NotNull final MultiHostRegistrar registrar, @NotNull final PsiElement context) {
    final FileType fileType = context.getContainingFile().getFileType();
    if (fileType != StdFileTypes.JSP && fileType != StdFileTypes.JSPX) {
      return;
    }

    if (CSS_ELEMENT_PATTERN.accepts(context)) {
      final TextRange range = new TextRange(1, context.getTextLength() - 1);
      registrar.startInjecting(CssFileType.INSTANCE.getLanguage())
        .addPlace("inline.style {", "}", (PsiLanguageInjectionHost)context, range)
        .doneInjecting();
    }
  }

  @NotNull
  public List<? extends Class<? extends PsiElement>> elementsToInjectIn() {
    return Collections.singletonList(XmlAttributeValue.class);
  }
}