content: /*
   * 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
   *
   *     https://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.avro.tool;
  
  import java.io.IOException;
  import java.io.InputStream;
  import java.io.PrintStream;
  import java.util.List;
  
  import org.apache.trevni.Input;
  import org.apache.trevni.ColumnFileReader;
  import org.apache.trevni.ColumnMetaData;
  import org.apache.trevni.ColumnValues;
  
  import com.fasterxml.jackson.core.JsonFactory;
  import com.fasterxml.jackson.core.JsonGenerator;
  import com.fasterxml.jackson.core.JsonEncoding;
  import com.fasterxml.jackson.core.util.MinimalPrettyPrinter;
  
  /**
   * Tool to read Trevni files and print them as JSON. This can read any Trevni
   * file. Nested structure is reconstructed from the columns rather than any
   * schema information.
   */
  public class TrevniToJsonTool implements Tool {
    static final JsonFactory FACTORY = new JsonFactory();
  
    private JsonGenerator generator;
    private ColumnValues[] values;
    private String[] shortNames;
  
    @Override
    public String getName() {
      return "trevni_tojson";
    }
  
    @Override
    public String getShortDescription() {
      return "Dumps a Trevni file as JSON.";
    }
  
    @Override
    public int run(InputStream stdin, PrintStream out, PrintStream err, List<String> args) throws Exception {
      String filename;
      boolean pretty = false;
      if (args.size() == 2 && "-pretty".equals(args.get(0))) {
        pretty = true;
        filename = args.get(1);
      } else if (args.size() == 1) {
        filename = args.get(0);
      } else {
        err.println("Usage: [-pretty] input");
        return 1;
      }
  
      toJson(TrevniUtil.input(filename), out, pretty);
  
      return 0;
    }
  
    /** Read a Trevni file and print each row as a JSON object. */
    public void toJson(Input input, PrintStream out, boolean pretty) throws IOException {
      this.generator = FACTORY.createGenerator(out, JsonEncoding.UTF8);
      if (pretty) {
        generator.useDefaultPrettyPrinter();
      } else { // ensure newline separation
        MinimalPrettyPrinter pp = new MinimalPrettyPrinter();
        pp.setRootValueSeparator(System.getProperty("line.separator"));
        generator.setPrettyPrinter(pp);
      }
  
      ColumnFileReader reader = new ColumnFileReader(input);
  
      int columnCount = (int) reader.getColumnCount();
      this.values = new ColumnValues[columnCount];
      this.shortNames = new String[columnCount];
      for (int i = 0; i < columnCount; i++) {
        values[i] = reader.getValues(i);
        shortNames[i] = shortName(reader.getColumnMetaData(i));
      }
  
      List<ColumnMetaData> roots = reader.getRoots();
      for (long row = 0; row < reader.getRowCount(); row++) {
        for (ColumnValues v : values)
          v.startRow();
        generator.writeStartObject();
        for (ColumnMetaData root : roots)
          valueToJson(root);
        generator.writeEndObject();
      }
      generator.flush();
      out.println();
      reader.close();
    }
  
    private void valueToJson(ColumnMetaData column) throws IOException {
      generator.writeFieldName(shortNames[column.getNumber()]);
      ColumnValues in = values[column.getNumber()];
      if (!column.isArray()) {
        primitiveToJson(column, in.nextValue());
      } else {
        generator.writeStartArray();
        int length = in.nextLength();
        for (int i = 0; i < length; i++) {
          Object value = in.nextValue();
          List<ColumnMetaData> children = column.getChildren();
          if (children.size() == 0) {
            primitiveToJson(column, value);
          } else {
            generator.writeStartObject();
            if (value != null) {
              generator.writeFieldName("value$");
              primitiveToJson(column, value);
            }
            for (ColumnMetaData child : children)
              valueToJson(child);
            generator.writeEndObject();
          }
        }
        generator.writeEndArray();
      }
    }
  
    private void primitiveToJson(ColumnMetaData column, Object value) throws IOException {
      switch (column.getType()) {
      case NULL:
        generator.writeNull();
        break;
      case BOOLEAN:
        generator.writeBoolean((Boolean) value);
        break;
      case INT:
        generator.writeNumber((Integer) value);
        break;
      case LONG:
        generator.writeNumber((Long) value);
        break;
      case FIXED32:
        generator.writeNumber((Integer) value);
        break;
      case FIXED64:
        generator.writeNumber((Long) value);
        break;
      case FLOAT:
        generator.writeNumber((Float) value);
        break;
      case DOUBLE:
        generator.writeNumber((Double) value);
        break;
      case STRING:
        generator.writeString((String) value);
        break;
      case BYTES:
        generator.writeBinary((byte[]) value);
        break;
      default:
        throw new RuntimeException("Unknown value type: " + column.getType());
      }
    }
  
    // trim off portion of name shared with parent
    private String shortName(ColumnMetaData column) {
      String name = column.getName();
      ColumnMetaData parent = column.getParent();
      if (parent != null && name.startsWith(parent.getName()))
        name = name.substring(parent.getName().length());
      if (!Character.isLetterOrDigit(name.charAt(0)))
        name = name.substring(1);
      return name;
    }
  
  }
  