/**
 * Copyright (c) 2008-2013, http://www.snakeyaml.org
 *
 * 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, Anchor, BlockEnd, BlockEntry, BlockMappingStart, BlockSequenceStart, Directive, DocumentEnd, DocumentStart, FlowEntry,
		FlowMappingEnd, FlowMappingStart, FlowSequenceEnd, FlowSequenceStart, Key, Scalar, StreamEnd, StreamStart, Tag, Value
	}

	private final Mark startMark;
	private final Mark endMark;

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

	@Override
	public String toString() {
		return "<" + this.getClass().getName() + "(" + getArguments() + ")>";
	}

	public Mark getStartMark() {
		return startMark;
	}

	public Mark getEndMark() {
		return endMark;
	}

	/**
	 * @see "__repr__ for Token in PyYAML"
	 */
	protected String getArguments() {
		return "";
	}

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

	/*
	 * for tests only
	 */
	@Override
	public boolean equals(final Object obj) {
		if (obj instanceof Token) {
			return toString().equals(obj.toString());
		} else {
			return false;
		}
	}

	/*
	 * for tests only
	 */
	@Override
	public int hashCode() {
		return toString().hashCode();
	}
}