morm/src/setfieldvaluehelper.h

/*
 * This file is a part of morm
 * and is distributed under the 2-Clause BSD licence.
 * Author: Tomasz Sowa <t.sowa@ttmath.org>
 */

/*
 * Copyright (c) 2019, Tomasz Sowa
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright notice,
 * this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 * notice, this list of conditions and the following disclaimer in the
 * documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 *
 */

#ifndef headerfile_morm_setfieldvaluehelper
#define headerfile_morm_setfieldvaluehelper

#include <vector>
#include <typeinfo>


namespace morm
{


struct FieldValueBase
{
	FieldValueBase()
	{
	}

	virtual ~FieldValueBase()
	{
	}

	virtual void set(void * value, const std::type_info & value_type_info) = 0;

};


template<typename FieldValue>
struct FieldValueContainer : public FieldValueBase
{
	FieldValueContainer(const FieldValue & value)
	{
		this->value = &value;
	}

	void set(void * value, const std::type_info & value_type_info)
	{
		if( value_type_info == typeid(FieldValue) )
		{
			FieldValue * field_value = reinterpret_cast<FieldValue*>(value);
			*field_value = *this->value;
		}
	}

	const FieldValue * value;

};




class SetFieldValueHelper
{
public:

	struct Item
	{
		const wchar_t * db_field_name;
		const wchar_t * flat_field_name;
		FieldValueBase * field_value_base;
		bool auto_remove_field_value_object;

		Item()
		{
			db_field_name = nullptr;
			flat_field_name = nullptr;
			field_value_base = nullptr;
			auto_remove_field_value_object = false;
		}

		~Item()
		{
		}
	};

	std::vector<Item> item_tab;


	SetFieldValueHelper()
	{
		clear();
	}


	virtual ~SetFieldValueHelper()
	{
		remove_field_value_base_objects();
	}


	virtual void remove_field_value_base_objects()
	{
		for(Item & item : item_tab)
		{
			if( item.auto_remove_field_value_object )
			{
				delete item.field_value_base;
				item.field_value_base = nullptr;
			}
		}
	}


	virtual void clear()
	{
		item_tab.clear();
	}


	virtual void add(const wchar_t * db_field_name, const wchar_t * flat_field_name)
	{
		add(db_field_name, flat_field_name, nullptr, false);
	}


	virtual void add(const wchar_t * db_field_name, const wchar_t * flat_field_name, FieldValueBase * field_value_base, bool auto_remove_field_value_object)
	{
		Item item;
		item.db_field_name = db_field_name;
		item.flat_field_name = flat_field_name;
		item.field_value_base = field_value_base;
		item.auto_remove_field_value_object = auto_remove_field_value_object;
		item_tab.push_back(item);
	}


	virtual size_t size()
	{
		return item_tab.size();
	}

	virtual bool empty()
	{
		return item_tab.empty();
	}

	virtual void add_field_value_container(size_t index, FieldValueBase * field_value_base, bool auto_remove_field_value_object)
	{
		if( item_tab[index].field_value_base && item_tab[index].auto_remove_field_value_object )
		{
			delete item_tab[index].field_value_base;
		}

		item_tab[index].field_value_base = field_value_base;
		item_tab[index].auto_remove_field_value_object = auto_remove_field_value_object;
	}

	template<typename FieldValue>
	void set_value(size_t index, FieldValue & value)
	{
		if( item_tab[index].field_value_base )
		{
			item_tab[index].field_value_base->set(&value, typeid(value));
		}
	}


	virtual const wchar_t * get_db_field_name(size_t index)
	{
		return item_tab[index].db_field_name;
	}


	virtual const wchar_t * get_flat_field_name(size_t index)
	{
		return item_tab[index].flat_field_name;
	}

};

}

#endif