/* ========================================================================
 * PlantUML : a free UML diagram generator
 * ========================================================================
 *
 * (C) Copyright 2009-2020, Arnaud Roques
 *
 * Project Info:  http://plantuml.com
 *
 * If you like this project or if you find it useful, you can support us at:
 *
 * http://plantuml.com/patreon (only 1$ per month!)
 * http://plantuml.com/paypal
 *
 * This file is part of PlantUML.
 *
 * PlantUML is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * PlantUML distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public
 * License for more details.
 *
 * You should have received a copy of the GNU General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
 * USA.
 *
 *
 * Original Author:  Arnaud Roques
 *
 */
package net.sourceforge.plantuml.tim.expression;

import net.sourceforge.plantuml.tim.Eater;
import net.sourceforge.plantuml.tim.EaterException;
import net.sourceforge.plantuml.tim.TLineType;

public enum TokenType {
	QUOTED_STRING, OPERATOR, OPEN_PAREN_MATH, COMMA, CLOSE_PAREN_MATH, NUMBER, PLAIN_TEXT, SPACES, FUNCTION_NAME, OPEN_PAREN_FUNC, CLOSE_PAREN_FUNC;

	private boolean isSingleChar1() {
		return this == OPEN_PAREN_MATH || this == COMMA || this == CLOSE_PAREN_MATH;
	}

	private static boolean isPlainTextBreak(char ch, char ch2) {
		final TokenType tmp = fromChar(ch, ch2);
		if (tmp.isSingleChar1() || tmp == TokenType.OPERATOR || tmp == SPACES) {
			return true;
		}
		return false;
	}

	private static TokenType fromChar(char ch, char ch2) {
		TokenType result = PLAIN_TEXT;
		if (TLineType.isQuote(ch)) {
			result = QUOTED_STRING;
		} else if (TokenOperator.getTokenOperator(ch, ch2) != null) {
			result = OPERATOR;
		} else if (ch == '(') {
			result = OPEN_PAREN_MATH;
		} else if (ch == ')') {
			result = CLOSE_PAREN_MATH;
		} else if (ch == ',') {
			result = COMMA;
		} else if (TLineType.isLatinDigit(ch)) {
			result = NUMBER;
		} else if (TLineType.isSpaceChar(ch)) {
			result = SPACES;
		}
		return result;
	}

	final static public Token eatOneToken(Eater eater, boolean manageColon) throws EaterException {
		final char ch = eater.peekChar();
		if (ch == 0) {
			return null;
		}
		if (manageColon && ch == ':') {
			return null;
		}
		final TokenOperator tokenOperator = TokenOperator.getTokenOperator(ch, eater.peekCharN2());
		if (TLineType.isQuote(ch)) {
			return new Token(eater.eatAndGetQuotedString(), TokenType.QUOTED_STRING);
		} else if (tokenOperator != null) {
			if (tokenOperator.getDisplay().length() == 1) {
				return new Token(eater.eatOneChar(), TokenType.OPERATOR);
			}
			return new Token("" + eater.eatOneChar() + eater.eatOneChar(), TokenType.OPERATOR);
		} else if (ch == '(') {
			return new Token(eater.eatOneChar(), TokenType.OPEN_PAREN_MATH);
		} else if (ch == ')') {
			return new Token(eater.eatOneChar(), TokenType.CLOSE_PAREN_MATH);
		} else if (ch == ',') {
			return new Token(eater.eatOneChar(), TokenType.COMMA);
		} else if (TLineType.isLatinDigit(ch)) {
			return new Token(eater.eatAndGetNumber(), TokenType.NUMBER);
		} else if (TLineType.isSpaceChar(ch)) {
			return new Token(eater.eatAndGetSpaces(), TokenType.SPACES);
		}
		return new Token(eatAndGetTokenPlainText(eater), TokenType.PLAIN_TEXT);
	}

	static private String eatAndGetTokenPlainText(Eater eater) throws EaterException {
		final StringBuilder result = new StringBuilder();
		while (true) {
			final char ch = eater.peekChar();
			if (ch == 0 || TokenType.isPlainTextBreak(ch, eater.peekCharN2())) {
				return result.toString();
			}
			result.append(eater.eatOneChar());
		}
	}

}
