sql_builder.hpp

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#ifndef NEFORCE_DATABASE_SQL_BUILDER_HPP__
#define NEFORCE_DATABASE_SQL_BUILDER_HPP__

 
#include "NeForce/core/container/vector.hpp"
#include "NeForce/core/memory/unique_ptr.hpp"
#include "NeForce/core/string/string.hpp"
NEFORCE_BEGIN_NAMESPACE__

 
#ifdef DELETE
#    undef DELETE
#endif

enum class sql_operate {
    SELECT, 
    INSERT, 
    UPDATE, 
    DELETE  
};

enum class sql_join {
    INNER, 
    LEFT,  
    RIGHT, 
    FULL   
};

enum class sql_order {
    ASC, 
    DESC 
};
 

class NEFORCE_API sql_builder {
public:
    struct select_data {
        vector<string> fields;            
        vector<string> join_clauses;      
        vector<string> group_by_fields;   
        vector<string> having_conditions; 
        vector<string> order_by_clauses;  
        int limit_count = -1;             
        int offset_count = -1;            
        bool distinct = false;            
    };

    struct insert_data {
        vector<string> fields;       
        vector<string> placeholders; 
    };

    struct update_data {
        vector<string> assignments; 
    };
 
private:
    sql_operate sql_type_ = sql_operate::SELECT; 
    string table_;                               
    string table_alias_;                         
    vector<string> where_conditions_;            
 
    unique_ptr<select_data> select_data_; 
    unique_ptr<insert_data> insert_data_; 
    unique_ptr<update_data> update_data_; 
 
private:
    select_data* ensure_select_data();
    insert_data* ensure_insert_data();
    update_data* ensure_update_data();
 
    void clear_data() noexcept;
 
public:
    sql_builder() = default;

    ~sql_builder() = default;

    sql_builder(const sql_builder& other);

    sql_builder& operator=(const sql_builder& other);
 
    sql_builder(sql_builder&&) noexcept = default;
    sql_builder& operator=(sql_builder&&) noexcept = default;

    sql_builder& select(vector<string> fields);

    sql_builder& select(std::initializer_list<string> fields);

    sql_builder& select(string field);

    sql_builder& select_all() noexcept;

    sql_builder& distinct();

    sql_builder& from(string table) noexcept;

    sql_builder& from(string table, string alias) noexcept;

    sql_builder& join(sql_join type, string table, string on_condition);

    sql_builder& join(string table, string on_condition);

    sql_builder& left_join(string table, string on_condition);

    sql_builder& right_join(string table, string on_condition);

    sql_builder& inner_join(string table, string on_condition);

    sql_builder& full_join(string table, string on_condition);

    sql_builder& where(string condition);

    sql_builder& where_eq(string field, string value);

    sql_builder& where_ne(string field, string value);

    sql_builder& where_gt(string field, string value);

    sql_builder& where_ge(string field, string value);

    sql_builder& where_lt(string field, string value);

    sql_builder& where_le(string field, string value);

    sql_builder& where_like(string field, string pattern);

    sql_builder& where_not_like(string field, string pattern);

    sql_builder& where_in(string field, vector<string> values);

    sql_builder& where_not_in(string field, vector<string> values);

    sql_builder& where_between(string field, string start, string end);

    sql_builder& where_not_between(string field, string start, string end);

    sql_builder& where_is_null(string field);

    sql_builder& where_is_not_null(string field);

    sql_builder& where_exists(string subquery);

    sql_builder& where_not_exists(string subquery);

    sql_builder& or_where(string condition);

    sql_builder& group_by(string field);

    sql_builder& group_by(const vector<string>& fields);

    sql_builder& having(string condition);

    sql_builder& order_by(string field, sql_order order = sql_order::ASC);

    sql_builder& order_by_asc(string field);

    sql_builder& order_by_desc(string field);

    sql_builder& limit(int count);

    sql_builder& offset(int count);

    sql_builder& page(int page_num, int page_size);

    sql_builder& insert_into(string table, vector<string> fields);

    sql_builder& insert_into(string table);

    sql_builder& values(vector<string> values);

    sql_builder& columns(vector<string> fields);

    sql_builder& update(string table);

    sql_builder& set(string assignment);

    sql_builder& set(string field, string value);

    sql_builder& set_increment(string field, int value = 1);

    sql_builder& set_decrement(string field, int value = 1);

    sql_builder& remove();

    sql_builder& delete_from(string table);
 
    sql_builder& select_count(string field, string alias); 
    sql_builder& select_count(string field);               
    sql_builder& select_count();                           
 
    sql_builder& select_sum(string field, string alias); 
    sql_builder& select_sum(string field);               
 
    sql_builder& select_avg(string field, string alias); 
    sql_builder& select_avg(string field);               
 
    sql_builder& select_max(string field, string alias); 
    sql_builder& select_max(string field);               
 
    sql_builder& select_min(string field, string alias); 
    sql_builder& select_min(string field);               

    sql_builder& select_distinct(string field);

    sql_builder& select_subquery(string subquery, string alias);

    sql_builder& select_subquery(string subquery);

    sql_builder& from_subquery(string subquery, string alias);

    sql_builder& reset() noexcept;

    NEFORCE_NODISCARD sql_operate type() const noexcept { return sql_type_; }

    NEFORCE_NODISCARD string_view table() const noexcept { return table_.view(); }

    NEFORCE_NODISCARD bool is_empty() const noexcept { return table_.empty(); }

    NEFORCE_NODISCARD string build() const;
};
 // SQL
 
NEFORCE_END_NAMESPACE__
#endif // NEFORCE_DATABASE_SQL_BUILDER_HPP__