/*
 * Copyright 2016 requery.io
 *
 * Licensed 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.
 */

package io.requery.sql.gen;

import io.requery.query.element.LimitedElement;
import io.requery.sql.Keyword;
import io.requery.sql.QueryBuilder;

import static io.requery.sql.Keyword.FETCH;
import static io.requery.sql.Keyword.NEXT;
import static io.requery.sql.Keyword.OFFSET;
import static io.requery.sql.Keyword.ONLY;
import static io.requery.sql.Keyword.ROW;
import static io.requery.sql.Keyword.ROWS;

public class OffsetFetchGenerator extends LimitGenerator {

    @Override
    public void write(Output output, LimitedElement query) {
        QueryBuilder qb = output.builder();
        Integer limit = query.getLimit();
        Integer offset = query.getOffset();
        write(qb, limit, offset);
    }

    protected void write(QueryBuilder qb, Integer limit, Integer offset) {
        if (offset != null) {
            qb.keyword(OFFSET)
                .value(offset)
                .keyword(offset > 1 ? ROWS : ROW)
                .keyword(FETCH, NEXT)
                .value(limit)
                .keyword(limit > 1 ? ROWS : ROW)
                .keyword(ONLY);
        } else if (limit != null) {
            qb.keyword(FETCH, Keyword.FIRST)
                .value(limit)
                .keyword(limit > 1 ? ROWS : ROW)
                .keyword(ONLY);
        }
    }
}

/*
 * Copyright 2016 requery.io
 *
 * Licensed 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.
 */

package io.requery.sql.gen;

import io.requery.query.element.LimitedElement;
import io.requery.sql.Keyword;
import io.requery.sql.QueryBuilder;

import static io.requery.sql.Keyword.FETCH;
import static io.requery.sql.Keyword.NEXT;
import static io.requery.sql.Keyword.OFFSET;
import static io.requery.sql.Keyword.ONLY;
import static io.requery.sql.Keyword.ROW;
import static io.requery.sql.Keyword.ROWS;

public class OffsetFetchGenerator extends LimitGenerator {

    @Override
    public void write(Output output, LimitedElement query) {
        QueryBuilder qb = output.builder();
        Integer limit = query.getLimit();
        if (limit != null && limit > 0) {
            Integer offset = query.getOffset();
            write(qb, limit, offset);
        }
    }

    protected void write(QueryBuilder qb, Integer limit, Integer offset) {
        if (offset != null) {
            qb.keyword(OFFSET)
                .value(offset)
                .keyword(offset > 1 ? ROWS : ROW)
                .keyword(FETCH, NEXT)
                .value(limit)
                .keyword(limit > 1 ? ROWS : ROW)
                .keyword(ONLY);
        } else if (limit != null) {
            qb.keyword(FETCH, Keyword.FIRST)
                .value(limit)
                .keyword(limit > 1 ? ROWS : ROW)
                .keyword(ONLY);
        }
    }
}

Resolve #193 Fix NPE in generation of offset/fetch