/**
* Copyright (C) 2009-2013 FoundationDB, LLC
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program 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 Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
package com.foundationdb.server.types.mcompat.mfuncs;
import com.foundationdb.server.error.InvalidParameterValueException;
import com.foundationdb.server.types.LazyList;
import com.foundationdb.server.types.TExecutionContext;
import com.foundationdb.server.types.TScalar;
import com.foundationdb.server.types.TOverloadResult;
import com.foundationdb.server.types.common.types.StringAttribute;
import com.foundationdb.server.types.common.types.StringFactory;
import com.foundationdb.server.types.mcompat.mtypes.MNumeric;
import com.foundationdb.server.types.mcompat.mtypes.MString;
import com.foundationdb.server.types.value.ValueSource;
import com.foundationdb.server.types.value.ValueTarget;
import com.foundationdb.server.types.texpressions.TInputSetBuilder;
import com.foundationdb.server.types.texpressions.TScalarBase;
import java.io.UnsupportedEncodingException;
/**
* ASCII function: return single encoded byte.
*/
public class MAscii extends TScalarBase
{
public static final TScalar INSTANCE = new MAscii();
private MAscii() {}
@Override
protected void buildInputSets(TInputSetBuilder builder)
{
builder.covers(MString.VARCHAR, 0);
}
@Override
public String displayName()
{
return "ascii";
}
@Override
public TOverloadResult resultType()
{
return TOverloadResult.fixed(MNumeric.INT, 3);
}
@Override
protected void doEvaluate(TExecutionContext context, LazyList<? extends ValueSource> inputs, ValueTarget output)
{
ValueSource sval = inputs.get(0);
String str = sval.getString();
int code = 0;
if (str.length() == 0) {
output.putInt32(0);
}
else {
String charset = StringFactory.Charset.of(context.inputTypeAt(0).attribute(StringAttribute.CHARSET));
try {
byte[] bytes = str.substring(0, 1).getBytes(charset);
output.putInt32(bytes[0] & 0xFF);
}
catch (UnsupportedEncodingException ex) {
context.warnClient(new InvalidParameterValueException("Invalid charset: " + charset));
output.putNull();
}
}
}
}