/*
 * 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.xml.util;

import com.intellij.openapi.diagnostic.Logger;
import com.intellij.openapi.util.JDOMUtil;
import com.intellij.openapi.util.io.FileUtilRt;
import com.intellij.openapi.util.text.StringUtil;
import com.intellij.openapi.vfs.CharsetToolkit;
import com.intellij.util.io.UnsyncByteArrayInputStream;
import com.intellij.util.xmlb.Converter;
import com.intellij.util.xmlb.XmlSerializer;
import com.intellij.util.xmlb.annotations.Attribute;
import com.intellij.util.xmlb.annotations.Tag;
import gnu.trove.THashSet;
import org.jdom.Document;
import org.jetbrains.annotations.NotNull;
import org.jetbrains.annotations.Nullable;

import java.io.InputStream;
import java.util.Collections;
import java.util.Locale;
import java.util.Set;

/**
 * @author Dennis.Ushakov
 */
public class HTMLControls {
  private static final Logger LOG = Logger.getInstance(HTMLControls.class);
  private static Control[] ourControls;

  public static Control[] getControls() {
    if (ourControls == null) {
      ourControls = loadControls();
    }
    return ourControls;
  }

  @SuppressWarnings("IOResourceOpenedButNotSafelyClosed")
  private static Control[] loadControls() {
    Document document;
    try {
      // use temporary bytes stream because otherwise inputStreamSkippingBOM will fail
      // on ZipFileInputStream used in jar files
      final InputStream stream = HTMLControls.class.getResourceAsStream("HtmlControls.xml");
      final byte[] bytes = FileUtilRt.loadBytes(stream);
      stream.close();
      final UnsyncByteArrayInputStream bytesStream = new UnsyncByteArrayInputStream(bytes);
      document = JDOMUtil.loadDocument(CharsetToolkit.inputStreamSkippingBOM(bytesStream));
      bytesStream.close();
    } catch (Exception e) {
      LOG.error(e);
      return new Control[0];
    }
    if (!document.getRootElement().getName().equals("htmlControls")) {
      LOG.error("HTMLControls storage is broken");
      return new Control[0];
    }
    return XmlSerializer.deserialize(document, Control[].class);
  }

  public enum TagState { REQUIRED, OPTIONAL, FORBIDDEN }

  @Tag("control")
  public static class Control {
    @Attribute("name")
    public String name;
    @Attribute(value = "startTag", converter = TagStateConverter.class)
    public TagState startTag;
    @Attribute(value = "endTag", converter = TagStateConverter.class)
    public TagState endTag;
    @Attribute("emptyAllowed")
    public boolean emptyAllowed;
    @Attribute(value = "autoClosedBy", converter = AutoCloseConverter.class)
    public Set<String> autoClosedBy = Collections.emptySet();
  }

  private static class TagStateConverter extends Converter<TagState> {
    @Nullable
    @Override
    public TagState fromString(@NotNull String value) {
      return TagState.valueOf(value.toUpperCase(Locale.US));
    }

    @NotNull
    @Override
    public String toString(@NotNull TagState state) {
      return state.name().toLowerCase(Locale.US);
    }
  }

  private static class AutoCloseConverter extends Converter<Set<String>> {
    @Nullable
    @Override
    public Set<String> fromString(@NotNull String value) {
      final THashSet<String> result = new THashSet<String>();
      for (String closingTag : StringUtil.split(value, ",")) {
        result.add(closingTag.trim());
      }
      return result;
    }

    @NotNull
    @Override
    public String toString(@NotNull Set<String> o) {
      return StringUtil.join(o, ", ");
    }
  }
}