/*******************************************************************************
 * 
 * Copyright 2010 Alexandru Craciun, and individual contributors as indicated
 * by the @authors tag. 
 * 
 * This is free software; you can redistribute it and/or modify it
 * under the terms of the GNU Lesser General Public License as
 * published by the Free Software Foundation; either version 3 of
 * the License, or (at your option) any later version.
 * 
 * This software is 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
 * Lesser General Public License for more details.
 * 
 * You should have received a copy of the GNU Lesser General Public
 * License along with this software; if not, write to the Free
 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA, or see the FSF site: http://www.fsf.org.
 ******************************************************************************/
/* Generated By:JJTree: Do not edit this line. ASTLogicalExpression.java Version 4.3 */
/* JavaCCOptions:MULTI=true,NODE_USES_PARSER=false,VISITOR=false,TRACK_TOKENS=false,NODE_PREFIX=AST,NODE_EXTENDS=,NODE_FACTORY=,SUPPORT_CLASS_VISIBILITY_PUBLIC=true */
package org.netxilia.spi.impl.formula.parser;

import org.netxilia.api.formula.IFormulaContext;
import org.netxilia.api.value.BooleanValue;
import org.netxilia.api.value.GenericValueType;
import org.netxilia.api.value.IGenericValue;

/**
 * An AST node representing a binary logical expression.
 */
public class ASTLogicalExpression extends ASTBinaryExpression {

	public ASTLogicalExpression(int id) {
		super(id, "Logical");
	}

	public ASTLogicalExpression(FormulaParser p, int id) {
		super(p, id, "Logical");
	}

	@Override
	public IGenericValue eval(IFormulaContext context) {
		ASTBaseNode nLeft = (ASTBaseNode) jjtGetChild(0);
		ASTBaseNode nRight = (ASTBaseNode) jjtGetChild(1);

		IGenericValue gvLeft = nLeft.eval(context);
		IGenericValue gvRight = nRight.eval(context);

		if (gvLeft.getValueType() == GenericValueType.ERROR) {
			return gvLeft;
		}
		if (gvRight.getValueType() == GenericValueType.ERROR) {
			return gvRight;
		}

		if (gvLeft.getValueType() != gvRight.getValueType()) {
			// TODO: refine this? in Excel you can compare apples & oranges... does it make sense?
			// ACR: should rather return false !?
			return BooleanValue.FALSE;
		}

		boolean result;
		if (gvLeft.getValueType() == GenericValueType.NUMBER) {
			result = compare(gvLeft.getNumberValue(), gvRight.getNumberValue());
		} else if (gvLeft.getValueType() == GenericValueType.BOOLEAN) {
			result = compare(gvLeft.getBooleanValue(), gvRight.getBooleanValue());
		} else if (gvLeft.getValueType() == GenericValueType.STRING) {
			result = compare(gvLeft.getStringValue(), gvRight.getStringValue());
		} else {
			throw new IllegalStateException("BUG: Don't know how to compare " + gvLeft.getValueType());
		}
		return BooleanValue.valueOf(result);
	}

	// < LOGICAL_OPERATOR: "=" | "<" | "<=" | ">" | ">=" | "<>" | "!=" >
	private <T extends Comparable<T>> boolean compare(T left, T right) {
		if ("=".equals(operator)) {
			return left.equals(right);
		}
		if ("<".equals(operator)) {
			return left.compareTo(right) < 0;
		}
		if ("<=".equals(operator)) {
			return left.compareTo(right) <= 0;
		}
		if (">".equals(operator)) {
			return left.compareTo(right) > 0;
		}
		if (">=".equals(operator)) {
			return left.compareTo(right) >= 0;
		}
		if ("<>".equals(operator) || "!=".equals(operator)) {
			return !left.equals(right);
		}
		throw new IllegalStateException("BUG: Unknown operator " + operator);
	}
}
/* JavaCC - OriginalChecksum=356fe7ccea5f65e8c905463f6abe5940 (do not edit this line) */