package net.sf.saxon.sql;
import net.sf.saxon.expr.Expression;
import net.sf.saxon.expr.SimpleExpression;
import net.sf.saxon.expr.StaticProperty;
import net.sf.saxon.expr.XPathContext;
import net.sf.saxon.instruct.Executable;
import net.sf.saxon.om.Item;
import net.sf.saxon.style.ExtensionInstruction;
import net.sf.saxon.trans.XPathException;
import net.sf.saxon.trans.SaxonErrorCode;
import net.sf.saxon.value.ObjectValue;

import java.sql.Connection;
import java.sql.SQLException;

/**
* An sql:close element in the stylesheet.
*/

public class SQLClose extends ExtensionInstruction {

    Expression connection = null;

    public void prepareAttributes() throws XPathException {
        String connectAtt = getAttributeList().getValue("", "connection");
        if (connectAtt==null) {
            reportAbsence("connection");
        } else {
            connection = makeExpression(connectAtt);
        }
    }

    public void validate() throws XPathException {
        super.validate();
        connection = typeCheck("connection", connection);
    }

    public Expression compile(Executable exec) throws XPathException {
        return new CloseInstruction(connection);
    }

    private static class CloseInstruction extends SimpleExpression {

        public static final int CONNECTION = 0;

        public CloseInstruction(Expression connect) {
            Expression[] sub = {connect};
            setArguments(sub);
        }
        /**
         * A subclass must provide one of the methods evaluateItem(), iterate(), or process().
         * This method indicates which of the three is provided.
         */

        public int getImplementationMethod() {
            return Expression.EVALUATE_METHOD;
        }

        public String getExpressionType() {
            return "sql:close";
        }

        public int computeCardinality() {
            return StaticProperty.ALLOWS_ZERO_OR_ONE;
        }

        public Item evaluateItem(XPathContext context) throws XPathException {
            Item conn = arguments[CONNECTION].evaluateItem(context);
            if (!(conn instanceof ObjectValue && ((ObjectValue)conn).getObject() instanceof Connection) ) {
                dynamicError("Value of connection expression is not a JDBC Connection", SaxonErrorCode.SXSQ0001, context);
            }
            Connection connection = (Connection)((ObjectValue)conn).getObject();
    		try {
                connection.close();
    	    } catch (SQLException ex) {
    			dynamicError("(SQL) Failed to close connection: " + ex.getMessage(), SaxonErrorCode.SXSQ0002, context);
            }
            return null;
        }
    }
}

//
// The contents of this file are subject to the Mozilla Public License Version 1.0 (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.mozilla.org/MPL/
//
// Software distributed under the License is distributed on an "AS IS" basis,
// WITHOUT WARRANTY OF ANY KIND, either express or implied.
// See the License for the specific language governing rights and limitations under the License.
//
// The Original Code is: all this file.
//
// The Initial Developer of the Original Code is Michael H. Kay.
//
// Portions created by (your name) are Copyright (C) (your legal entity). All Rights Reserved.
//
// Additional Contributor(s): Rick Bonnett [rbonnett@acadia.net]
//
