/*
    *    Copyright 2016-2025 the original author or authors.
    *
    *    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
    *
    *       https://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 org.mybatis.dynamic.sql.select.render;
  
  import java.util.Objects;
  
  import org.jspecify.annotations.Nullable;
  import org.mybatis.dynamic.sql.render.RenderingContext;
  import org.mybatis.dynamic.sql.select.PagingModel;
  import org.mybatis.dynamic.sql.util.FragmentAndParameters;
  
  public class PagingModelRenderer {
      private final PagingModel pagingModel;
      private final RenderingContext renderingContext;
  
      private PagingModelRenderer(Builder builder) {
          renderingContext = Objects.requireNonNull(builder.renderingContext);
          pagingModel = Objects.requireNonNull(builder.pagingModel);
      }
  
      public FragmentAndParameters render() {
          return pagingModel.limit().map(this::limitAndOffsetRender)
                  .orElseGet(this::fetchFirstRender);
      }
  
      private FragmentAndParameters limitAndOffsetRender(Long limit) {
          return new LimitAndOffsetPagingModelRenderer(renderingContext, limit, pagingModel).render();
      }
  
      private FragmentAndParameters fetchFirstRender() {
          return new FetchFirstPagingModelRenderer(renderingContext, pagingModel).render();
      }
  
      public static class Builder {
          private @Nullable PagingModel pagingModel;
          private @Nullable RenderingContext renderingContext;
  
          public Builder withRenderingContext(RenderingContext renderingContext) {
              this.renderingContext = renderingContext;
              return this;
          }
  
          public Builder withPagingModel(PagingModel pagingModel) {
              this.pagingModel = pagingModel;
              return this;
          }
  
          public PagingModelRenderer build() {
              return new PagingModelRenderer(this);
          }
      }
  }