/*
    * Licensed to the Apache Software Foundation (ASF) under one
    * or more contributor license agreements.  See the NOTICE file
    * distributed with this work for additional information
    * regarding copyright ownership.  The ASF licenses this file
    * to you 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 org.apache.maven.model.io;
  
  import javax.inject.Inject;
  import javax.inject.Named;
  import javax.inject.Singleton;
  
  import java.io.File;
  import java.io.IOException;
  import java.io.InputStream;
  import java.io.Reader;
  import java.nio.file.Path;
  import java.util.Map;
  import java.util.Objects;
  
  import org.apache.maven.model.InputSource;
  import org.apache.maven.model.Model;
  import org.apache.maven.model.building.ModelSourceTransformer;
  import org.apache.maven.model.building.TransformerContext;
  import org.apache.maven.model.v4.MavenXpp3Reader;
  import org.apache.maven.model.v4.MavenXpp3ReaderEx;
  import org.codehaus.plexus.util.ReaderFactory;
  import org.codehaus.plexus.util.xml.XmlStreamReader;
  import org.codehaus.plexus.util.xml.pull.EntityReplacementMap;
  import org.codehaus.plexus.util.xml.pull.MXParser;
  import org.codehaus.plexus.util.xml.pull.XmlPullParser;
  import org.codehaus.plexus.util.xml.pull.XmlPullParserException;
  
  /**
   * Handles deserialization of a model from some kind of textual format like XML.
   *
   * @author Benjamin Bentmann
   */
  @Named
  @Singleton
  public class DefaultModelReader implements ModelReader {
      private final ModelSourceTransformer transformer;
  
      @Inject
      public DefaultModelReader(ModelSourceTransformer transformer) {
          this.transformer = transformer;
      }
  
      @Override
      public Model read(File input, Map<String, ?> options) throws IOException {
          Objects.requireNonNull(input, "input cannot be null");
  
          try (XmlStreamReader in = ReaderFactory.newXmlReader(input)) {
              Model model = read(in, input.toPath(), options);
  
              model.setPomFile(input);
  
              return model;
          }
      }
  
      @Override
      public Model read(Reader input, Map<String, ?> options) throws IOException {
          Objects.requireNonNull(input, "input cannot be null");
  
          try (Reader in = input) {
              return read(in, null, options);
          }
      }
  
      @Override
      public Model read(InputStream input, Map<String, ?> options) throws IOException {
          Objects.requireNonNull(input, "input cannot be null");
  
          try (XmlStreamReader in = ReaderFactory.newXmlReader(input)) {
              return read(in, null, options);
          }
      }
  
      private boolean isStrict(Map<String, ?> options) {
          Object value = (options != null) ? options.get(IS_STRICT) : null;
          return value == null || Boolean.parseBoolean(value.toString());
      }
  
      private InputSource getSource(Map<String, ?> options) {
          Object value = (options != null) ? options.get(INPUT_SOURCE) : null;
          return (InputSource) value;
     }
 
     private TransformerContext getTransformerContext(Map<String, ?> options) {
         Object value = (options != null) ? options.get(TRANSFORMER_CONTEXT) : null;
         return (TransformerContext) value;
     }
 
     private Model read(Reader reader, Path pomFile, Map<String, ?> options) throws IOException {
         try {
             XmlPullParser parser = new MXParser(EntityReplacementMap.defaultEntityReplacementMap);
             parser.setInput(reader);
 
             TransformerContext context = getTransformerContext(options);
             XmlPullParser transformingParser =
                     context != null ? transformer.transform(parser, pomFile, context) : parser;
 
             InputSource source = getSource(options);
             boolean strict = isStrict(options);
             if (source != null) {
                 return readModelEx(transformingParser, source, strict);
             } else {
                 return readModel(transformingParser, strict);
             }
         } catch (XmlPullParserException e) {
             throw new ModelParseException(e.getMessage(), e.getLineNumber(), e.getColumnNumber(), e);
         } catch (IOException e) {
             throw e;
         } catch (Exception e) {
             throw new IOException("Unable to transform pom", e);
         }
     }
 
     private Model readModel(XmlPullParser parser, boolean strict) throws XmlPullParserException, IOException {
         MavenXpp3Reader mr = new MavenXpp3Reader();
         return new Model(mr.read(parser, strict));
     }
 
     private Model readModelEx(XmlPullParser parser, InputSource source, boolean strict)
             throws XmlPullParserException, IOException {
         MavenXpp3ReaderEx mr = new MavenXpp3ReaderEx();
         return new Model(mr.read(
                 parser, strict, new org.apache.maven.api.model.InputSource(source.getModelId(), source.getLocation())));
     }
 }