/*
* Licensed to Crate under one or more contributor license agreements.
* See the NOTICE file distributed with this work for additional
* information regarding copyright ownership. Crate licenses this file
* to you 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.
*
* However, if you have executed another commercial license agreement
* with Crate these terms will supersede the license and you may use the
* software solely pursuant to the terms of the relevant commercial
* agreement.
*/
package io.crate.operation.scalar;
import com.google.common.base.Preconditions;
import io.crate.metadata.*;
import io.crate.data.Input;
import io.crate.types.ArrayType;
import io.crate.types.DataType;
import io.crate.types.DataTypes;
import java.util.LinkedHashSet;
import java.util.List;
import java.util.Locale;
import java.util.Set;
class ArrayUniqueFunction extends Scalar<Object[], Object> {
public static final String NAME = "array_unique";
private final FunctionInfo functionInfo;
private final DataType<?> elementType;
private static FunctionInfo createInfo(List<DataType> types) {
ArrayType arrayType = (ArrayType) types.get(0);
if (arrayType.innerType().equals(DataTypes.UNDEFINED) && types.size() == 2) {
arrayType = (ArrayType) types.get(1);
}
return new FunctionInfo(new FunctionIdent(NAME, types), arrayType);
}
public static void register(ScalarFunctionModule module) {
module.register(NAME, new Resolver());
}
private ArrayUniqueFunction(FunctionInfo functionInfo) {
this.functionInfo = functionInfo;
this.elementType = ((ArrayType) functionInfo.returnType()).innerType();
}
@Override
public FunctionInfo info() {
return functionInfo;
}
@Override
public Object[] evaluate(Input[] args) {
Set<Object> uniqueSet = new LinkedHashSet<>();
for (Input array : args) {
assert array != null : "inputs must never be null";
Object[] arrayValue = (Object[]) array.value();
if (arrayValue == null) {
continue;
}
for (Object element : arrayValue) {
uniqueSet.add(elementType.value(element));
}
}
return uniqueSet.toArray();
}
private static class Resolver extends BaseFunctionResolver {
protected Resolver() {
super(Signature.numArgs(1, 2).and(Signature.withLenientVarArgs(Signature.ArgMatcher.ANY_ARRAY)));
}
@Override
public FunctionImplementation getForTypes(List<DataType> dataTypes) throws IllegalArgumentException {
Preconditions.checkArgument(
dataTypes.size() >= 1 && dataTypes.size() <= 2, "array_unique function requires one or two arguments");
for (int i = 0; i < dataTypes.size(); i++) {
Preconditions.checkArgument(dataTypes.get(i) instanceof ArrayType, String.format(Locale.ENGLISH,
"Argument %d of the array_unique function cannot be converted to array", i + 1));
}
if (dataTypes.size() == 2) {
DataType innerType0 = ((ArrayType) dataTypes.get(0)).innerType();
DataType innerType1 = ((ArrayType) dataTypes.get(1)).innerType();
Preconditions.checkArgument(
!innerType0.equals(DataTypes.UNDEFINED) || !innerType1.equals(DataTypes.UNDEFINED),
"One of the arguments of the array_unique function can be of undefined inner type, but not both");
if (!innerType0.equals(DataTypes.UNDEFINED)) {
Preconditions.checkArgument(innerType1.isConvertableTo(innerType0),
String.format(Locale.ENGLISH,
"Second argument's inner type (%s) of the array_unique function cannot be converted to the first argument's inner type (%s)",
innerType1, innerType0));
}
} else if (dataTypes.size() == 1) {
DataType innerType = ((ArrayType) dataTypes.get(0)).innerType();
Preconditions.checkArgument(!innerType.equals(DataTypes.UNDEFINED),
"When used with only one argument, the inner type of the array argument cannot be undefined");
}
return new ArrayUniqueFunction(createInfo(dataTypes));
}
}
}