xml/impl/src/com/intellij/codeInsight/template/emmet/generators/ZenCodingGenerator.java

/*
 * Copyright 2000-2014 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.codeInsight.template.emmet.generators;

import com.intellij.codeInsight.template.CustomTemplateCallback;
import com.intellij.codeInsight.template.emmet.EmmetParser;
import com.intellij.codeInsight.template.emmet.XmlEmmetParser;
import com.intellij.codeInsight.template.emmet.ZenCodingTemplate;
import com.intellij.codeInsight.template.emmet.tokens.TemplateToken;
import com.intellij.codeInsight.template.emmet.tokens.ZenCodingToken;
import com.intellij.codeInsight.template.impl.TemplateImpl;
import com.intellij.openapi.editor.Editor;
import com.intellij.openapi.extensions.ExtensionPointName;
import com.intellij.openapi.options.UnnamedConfigurable;
import com.intellij.openapi.util.text.StringUtil;
import com.intellij.psi.PsiElement;
import org.jetbrains.annotations.NotNull;
import org.jetbrains.annotations.Nullable;

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


/**
 * @author Eugene.Kudelevsky
 */
public abstract class ZenCodingGenerator {
  private static final ExtensionPointName<ZenCodingGenerator> EP_NAME = new ExtensionPointName<ZenCodingGenerator>("com.intellij.xml.zenCodingGenerator");

  public abstract TemplateImpl generateTemplate(@NotNull TemplateToken token, boolean hasChildren, @NotNull PsiElement context);

  @Nullable
  public TemplateImpl createTemplateByKey(@NotNull String key) {
    return null;
  }

  public abstract boolean isMyContext(@NotNull PsiElement context, boolean wrapping);

  @Nullable
  public String getSuffix() {
    return null;
  }

  public abstract boolean isAppliedByDefault(@NotNull PsiElement context);
  
  public abstract boolean isEnabled();

  public static List<ZenCodingGenerator> getInstances() {
    List<ZenCodingGenerator> generators = new ArrayList<ZenCodingGenerator>();
    Collections.addAll(generators, XmlZenCodingGeneratorImpl.INSTANCE);
    Collections.addAll(generators, EP_NAME.getExtensions());
    return generators;
  }

  @Nullable
  public String computeTemplateKey(@NotNull CustomTemplateCallback callback) {
    Editor editor = callback.getEditor();
    int currentOffset = editor.getCaretModel().getOffset();
    int startOffset = editor.getDocument().getLineStartOffset(editor.getCaretModel().getLogicalPosition().line);
    String key = computeKey(editor.getDocument().getCharsSequence().subSequence(startOffset, currentOffset));
    return !StringUtil.isEmpty(key) && ZenCodingTemplate.checkTemplateKey(key, callback, this) ? key : null;
  }
  
  @Nullable
  protected String computeKey(@NotNull CharSequence text) {
    int currentOffset = text.length();
    int groupCount = 0;
    int bracketCount = 0;
    int textCount = 0;

    while (currentOffset > 0) {
      currentOffset--;
      char c = text.charAt(currentOffset);

      if (c == ']') {
        bracketCount++;
      }
      else if (c == '[') {
        if (bracketCount == 0) {
          currentOffset++;
          break;
        }
        bracketCount--;
      }
      else if (c == '}') {
        textCount++;
      }
      else if (c == '{') {
        if (textCount == 0) {
          currentOffset++;
          break;
        }
        textCount--;
      }
      else if (c == ')') {
        groupCount++;
      }
      else if (c == '(') {
        if (groupCount == 0) {
          currentOffset++;
          break;
        }
        groupCount--;
      }
      else {
        if (bracketCount > 0 || textCount > 0) {
          // respect all characters inside attribute sets or text nodes
          continue;
        }
        if (!isAllowedChar(c)) {
          currentOffset++;
          break;
        }
      }
    }
    return groupCount == 0 && textCount == 0 && bracketCount == 0 && currentOffset >= 0 && currentOffset < text.length() 
           ? text.subSequence(currentOffset, text.length()).toString().replaceFirst("^[*+>^]+", "") 
           : null;
  }

  private static boolean isAllowedChar(char c) {
    return (Character.isDigit(c) || Character.isLetter(c) || StringUtil.containsChar("/>+^[](){}#.*:$-_!@|%", c));
  }

  @NotNull
  public EmmetParser createParser(List<ZenCodingToken> tokens,
                                  CustomTemplateCallback callback,
                                  ZenCodingGenerator generator,
                                  boolean surroundWithTemplate) {
    return new XmlEmmetParser(tokens, callback, generator, surroundWithTemplate);
  }
  
  @Nullable
  public UnnamedConfigurable createConfigurable() {
    return null;
  }

  public boolean hasCompletionItem() {
    return false;
  }
}