/**
 * @file mix_cc/sql/where.h
 * @brief 查询条件
 * @author Cat (null.null.null@qq.com)
 * @version 0.1
 * @date 2021-09-17
 * 
 * Copyright: Baosight Co. Ltd.
 * DO NOT COPY/USE WITHOUT PERMISSION
 * 
 */
#pragma once
#include <mix_cc/sql/public.h>
#include <mix_cc/sql/condition.h>
#include <mix_cc/sql/statement.h>
#include <string>
#include <algorithm>

namespace mix_cc {
namespace sql {

template <typename PrevStatement, typename... Conditions>
struct where_t : public prev_statement_t<PrevStatement>, public statement_t {
  static constexpr auto s_text = op::cmd_t::where;

  constexpr explicit where_t(PrevStatement prev_st, Conditions... conditions)
      : prev_statement_t<PrevStatement>(prev_st), conditions_(conditions...) {}

  constexpr auto get_command() {
    auto sel_str_c = " "_s + s_text + " "_s;
    auto conditions_str =
        hana::transform(conditions_, [](auto col) { return col.get_str(); });
    auto r_str = hana::fold_left(conditions_str, [](auto cond1, auto cond2) {
      return cond1 + " AND " + cond2;
    });
    return std::string(sel_str_c.c_str()) + r_str;
  }

  hana::tuple<Conditions...> conditions_;
};
}  // namespace sql
}  // namespace mix_cc