/**
 * Copyright (c) 2008, SnakeYAML
 *
 * 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 org.yaml.snakeyaml.tokens;

import org.yaml.snakeyaml.error.Mark;
import org.yaml.snakeyaml.error.YAMLException;

public abstract class Token {

  public enum ID {
    Alias("<alias>"), Anchor("<anchor>"), BlockEnd("<block end>"), BlockEntry(
        "-"), BlockMappingStart("<block mapping start>"), BlockSequenceStart(
            "<block sequence start>"), Directive("<directive>"), DocumentEnd(
                "<document end>"), DocumentStart("<document start>"), FlowEntry(
                    ","), FlowMappingEnd("}"), FlowMappingStart("{"), FlowSequenceEnd(
                        "]"), FlowSequenceStart("["), Key("?"), Scalar("<scalar>"), StreamEnd(
                            "<stream end>"), StreamStart("<stream start>"), Tag("<tag>"), Value(
                                ":"), Whitespace("<whitespace>"), Comment("#"), Error("<error>");

    private final String description;

    ID(String s) {
      description = s;
    }

    @Override
    public String toString() {
      return description;
    }
  }

  private final Mark startMark;
  private final Mark endMark;

  public Token(Mark startMark, Mark endMark) {
    if (startMark == null || endMark == null) {
      throw new YAMLException("Token requires marks.");
    }
    this.startMark = startMark;
    this.endMark = endMark;
  }

  public Mark getStartMark() {
    return startMark;
  }

  public Mark getEndMark() {
    return endMark;
  }

  /**
   * For error reporting.
   *
   * @see "class variable 'id' in PyYAML"
   * @return ID of this token
   */
  public abstract Token.ID getTokenId();
}
