/*
    *    Copyright 2009-2022 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.apache.ibatis.submitted.mapper_type_parameter;
  
  import java.util.List;
  import java.util.Map;
  
  import org.apache.ibatis.annotations.InsertProvider;
  import org.apache.ibatis.annotations.MapKey;
  import org.apache.ibatis.annotations.Options;
  import org.apache.ibatis.annotations.SelectProvider;
  import org.apache.ibatis.annotations.UpdateProvider;
  
  public interface BaseMapper<S, T> {
  
    @SelectProvider(type = StatementProvider.class, method = "provideSelect")
    S select(S param);
  
    @SelectProvider(type = StatementProvider.class, method = "provideSelect")
    List<S> selectList(S param);
  
    @SelectProvider(type = StatementProvider.class, method = "provideSelect")
    @MapKey("id")
    Map<T, S> selectMap(S param);
  
    @InsertProvider(type = StatementProvider.class, method = "provideInsert")
    @Options(useGeneratedKeys = true, keyProperty = "id")
    int insert(List<S> param);
  
    @UpdateProvider(type = StatementProvider.class, method = "provideUpdate")
    int update(S param);
  
    class StatementProvider {
      public String provideSelect(Object param) {
        StringBuilder sql = new StringBuilder("select * from ");
        if (param == null || param instanceof Person) {
          sql.append(" person ");
          if (param != null && ((Person) param).getId() != null) {
            sql.append(" where id = #{id}");
          }
        } else if (param instanceof Country) {
          sql.append(" country ");
          if (((Country) param).getId() != null) {
            sql.append(" where id = #{id}");
          }
        }
        sql.append(" order by id");
        return sql.toString();
      }
  
      public String provideInsert(Map<String, Object> map) {
        List<?> params = (List<?>) map.get("list");
        StringBuilder sql = null;
        for (int i = 0; i < params.size(); i++) {
          Object param = params.get(i);
          if (sql == null) {
            sql = new StringBuilder("insert into ");
            sql.append(param instanceof Country ? " country " : " person");
            sql.append(" (id, name) values ");
          } else {
            sql.append(",");
          }
          sql.append(" (#{list[").append(i).append("].id}, #{list[").append(i).append("].name})");
        }
        return sql == null ? "" : sql.toString();
      }
  
      public String provideUpdate(Object param) {
        StringBuilder sql = new StringBuilder("update ");
        if (param instanceof Person) {
          sql.append(" person set name = #{name} where id = #{id}");
        } else if (param instanceof Country) {
          sql.append(" country set name = #{name} where id = #{id}");
        }
        return sql.toString();
      }
    }
  }