/*
 * 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) 2018-2021, 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.
 *
 */

#include "model.h"


namespace morm
{

Model::Model()
{
	model_connector = nullptr;
	model_env = nullptr;
	save_mode = DO_INSERT_ON_SAVE;
	has_primary_key_set = false;
}


Model::Model(const Model & m)
{
	model_connector = m.model_connector;
	save_mode = m.save_mode;
	model_env = nullptr;
	has_primary_key_set = m.has_primary_key_set;
}


Model::~Model()
{
}


void Model::set_save_mode(SaveMode save_mode)
{
	this->save_mode = save_mode;
}


Model::SaveMode Model::get_save_mode()
{
	return save_mode;
}


void Model::set_has_primary_key_set(bool has_primary_key)
{
	this->has_primary_key_set = has_primary_key;
}


bool Model::get_has_primary_key_set()
{
	return this->has_primary_key_set;
}



void Model::mark_to_delete()
{
	save_mode = DO_DELETE_ON_SAVE;
}

void Model::mark_to_remove()
{
	save_mode = DO_DELETE_ON_SAVE;
}

void Model::mark_to_insert()
{
	save_mode = DO_INSERT_ON_SAVE;
}


void Model::mark_to_update()
{
	save_mode = DO_UPDATE_ON_SAVE;
}



void Model::table_name(PT::TextStream & stream)
{
}



void Model::set_connector(ModelConnector & connector)
{
	set_connector(&connector);
}


void Model::set_connector(ModelConnector * connector)
{
	model_connector = connector;
}


ModelConnector * Model::get_connector()
{
	return model_connector;
}


bool Model::object_exists()
{
	return save_mode == DO_UPDATE_ON_SAVE;
}


bool Model::found()
{
	return save_mode == DO_UPDATE_ON_SAVE;
}


void Model::to_text(PT::TextStream & stream, ModelData * model_data, bool clear_stream, bool dump_mode)
{
	if( clear_stream )
	{
		stream.clear();
	}

	ModelEnv model_env_local;
	model_env = &model_env_local;

	model_env->has_primary_key_set = has_primary_key_set;
	model_env->model_work_mode = MORM_MODEL_WORK_MODE_GENERATING_FLAT_STRING;
	model_env->dump_mode = dump_mode;
	model_env->model_data = model_data;

	if( model_connector )
	{
		FlatConnector * flat_connector = model_connector->get_flat_connector();

		if( flat_connector )
		{
			try
			{
				flat_connector->to_text(stream, *this);
			}
			catch(...)
			{
				model_env = nullptr;
				throw;
			}
		}
	}

	model_env = nullptr;
}


void Model::to_text(PT::TextStream & stream, ModelData & model_data, bool clear_stream, bool dump_mode)
{
	to_text(stream, &model_data, clear_stream, dump_mode);
}


void Model::to_text(PT::TextStream & stream, bool clear_stream, bool dump_mode)
{
	to_text(stream, nullptr, clear_stream, dump_mode);
}



void Model::to_text(std::string & str, ModelData * model_data, bool clear_string, bool dump_mode)
{
	if( model_connector )
	{
		// CHECK ME what if the stream is being used by something other?
		PT::TextStream * out_stream = model_connector->get_stream();

		if( out_stream )
		{
			to_text(*out_stream, model_data, true, dump_mode);
			out_stream->to_string(str, clear_string);
		}
	}
}


void Model::to_text(std::string & str, ModelData & model_data, bool clear_string, bool dump_mode)
{
	to_text(str, &model_data, clear_string, dump_mode);
}


void Model::to_text(std::string & str, bool clear_string, bool dump_mode)
{
	to_text(str, nullptr, clear_string, dump_mode);
}


std::string Model::to_text()
{
	std::string str;

	to_text(str, false);
	return str;
}


std::string Model::to_string()
{
	return to_text();
}



void Model::generate_insert_query(PT::TextStream & stream, ModelData * model_data)
{
	ModelEnv model_env_local;
	model_env = &model_env_local;
	model_env->has_primary_key_set = has_primary_key_set;
	model_env->model_data = model_data;
	model_env->model_work_mode = MORM_MODEL_WORK_MODE_GENERATING_DB_SQL;

	if( model_connector )
	{
		DbConnector * db_connector = model_connector->get_db_connector();

		if( db_connector )
		{
			try
			{
				db_connector->generate_insert_query(stream, *this);
			}
			catch(...)
			{
				model_env = nullptr;
				throw;
			}
		}
	}

	model_env = nullptr;
}


bool Model::insert(ModelData & model_data, bool insert_whole_tree)
{
	return insert(&model_data, insert_whole_tree);
}


bool Model::insert(bool insert_whole_tree)
{
	return insert(nullptr, insert_whole_tree);
}


bool Model::insert(ModelData * model_data, bool insert_whole_tree)
{
	ModelEnv model_env_local;
	model_env = &model_env_local;

	model_env->model_data = model_data;
	bool status = false;

	try
	{
		status = insert_tree(insert_whole_tree);
	}
	catch(...)
	{
		model_env = nullptr;
		throw;
	}

	model_env = nullptr;
	return status;
}


// has ModelEnv set
// FIX ME we need to propagage the status from the whole tree, if there is an error somewhere then we should return error from the parent
bool Model::insert_tree(bool insert_whole_tree)
{
	bool result = false;
	has_primary_key_set = false; // the key will be overwritten (the database will create a new key)
	model_env->has_primary_key_set = false;

	if( insert_whole_tree )
	{
		model_env->model_work_mode = MORM_MODEL_WORK_MODE_ITERATE_THROUGH_CHILDS_WITH_FOREIGN_KEY;
		model_env->model_work_submode = MORM_MODEL_WORK_SUBMODE_INSERT;
		map_fields();
	}

	if( model_connector )
	{
		model_env->model_work_mode = MORM_MODEL_WORK_MODE_GENERATING_DB_SQL;
		DbConnector * db_connector = model_connector->get_db_connector();

		// CHECK ME what if the stream is being used by something other?
		PT::TextStream * out_stream = model_connector->get_stream();

		if( db_connector && out_stream )
		{

			before_insert();
			out_stream->clear();
			result = db_connector->insert(*out_stream, *this);

			if( result )
			{
				/*
				 * after_insert() should read the new primary key and set has_primary_key_set flag if the key was read correctly
				 */
				after_insert();
				model_env->has_primary_key_set = has_primary_key_set;

				if( has_primary_key_set )
				{
					save_mode = DO_UPDATE_ON_SAVE;
					set_parent_key_in_childs(); // may it would be better to set it even if we do not have a primary key? set it to zero or something?
				}
				else
				{
					save_mode = DO_NOTHING_ON_SAVE;
				}
			}
			else
			{
				after_insert_failure();
			}
		}
	}

	if( insert_whole_tree )
	{
		model_env->model_work_mode = MORM_MODEL_WORK_MODE_ITERATE_THROUGH_CHILDS_WITHOUT_FOREIGN_KEY;
		model_env->model_work_submode = MORM_MODEL_WORK_SUBMODE_INSERT;
		map_fields();
	}

	return result;
}



void Model::generate_update_query(PT::TextStream & stream, ModelData * model_data)
{
	ModelEnv model_env_local;
	model_env = &model_env_local;
	model_env->has_primary_key_set = has_primary_key_set;
	model_env->model_data = model_data;
	model_env->model_work_mode = MORM_MODEL_WORK_MODE_GENERATING_DB_SQL;

	if( model_connector )
	{
		DbConnector * db_connector = model_connector->get_db_connector();

		if( db_connector )
		{
			db_connector->generate_update_query(stream, *this);
		}
	}

	// what about if an exception was thrown? this pointer will not be null
	model_env = nullptr;
}


bool Model::update(ModelData & model_data, bool update_whole_tree)
{
	return update(&model_data, update_whole_tree);
}


bool Model::update(bool update_whole_tree)
{
	return update(nullptr, update_whole_tree);
}


bool Model::update(ModelData * model_data, bool update_whole_tree)
{
	ModelEnv model_env_local;
	model_env = &model_env_local;

	model_env->model_data = model_data;
	bool status = false;

	try
	{
		status = update_tree(update_whole_tree);
	}
	catch(...)
	{
		model_env = nullptr;
		throw;
	}

	model_env = nullptr;
	return status;
}


// FIX ME we need to propagage the status from the whole tree, if there is an error somewhere then we should return error from the parent
bool Model::update_tree(bool update_whole_tree)
{
	bool result = false;
	model_env->has_primary_key_set = has_primary_key_set;

	if( !has_primary_key_set )
	{
		put_to_log(L"Morm: call update but model doesn't have a primary key set");
		return result;
	}

	if( update_whole_tree )
	{
		model_env->model_work_mode = MORM_MODEL_WORK_MODE_ITERATE_THROUGH_CHILDS_WITH_FOREIGN_KEY;
		model_env->model_work_submode = MORM_MODEL_WORK_SUBMODE_UPDATE;
		map_fields();
	}

	if( model_connector )
	{
		model_env->model_work_mode = MORM_MODEL_WORK_MODE_GENERATING_DB_SQL;
		DbConnector * db_connector = model_connector->get_db_connector();

		// CHECK ME what if the stream is being used by something other?
		PT::TextStream * out_stream = model_connector->get_stream();

		if( db_connector && out_stream )
		{
			before_update();
			out_stream->clear();
			result = db_connector->update(*out_stream, *this);

			if( result )
				after_update();
			else
				after_update_failure();
		}
	}

	if( update_whole_tree )
	{
		model_env->model_work_mode = MORM_MODEL_WORK_MODE_ITERATE_THROUGH_CHILDS_WITHOUT_FOREIGN_KEY;
		model_env->model_work_submode = MORM_MODEL_WORK_SUBMODE_UPDATE;
		map_fields();
	}

	return result;
}


void Model::generate_remove_query(PT::TextStream & stream, ModelData * model_data)
{
	ModelEnv model_env_local;
	model_env = &model_env_local;
	model_env->has_primary_key_set = has_primary_key_set;
	model_env->model_data = model_data;
	model_env->model_work_mode = MORM_MODEL_WORK_MODE_GENERATING_DB_SQL;

	if( model_connector )
	{
		DbConnector * db_connector = model_connector->get_db_connector();

		if( db_connector )
		{
			db_connector->generate_remove_query(stream, *this);
		}
	}

	// what about if an exception was thrown? this pointer will not be null
	model_env = nullptr;
}



bool Model::remove(ModelData & model_data, bool remove_whole_tree)
{
	return remove(&model_data, remove_whole_tree);
}


bool Model::remove(bool remove_whole_tree)
{
	return remove(nullptr, remove_whole_tree);
}


bool Model::remove(ModelData * model_data, bool remove_whole_tree)
{
	ModelEnv model_env_local;
	model_env = &model_env_local;

	model_env->model_data = model_data;
	bool status = false;

	try
	{
		status = remove_tree(remove_whole_tree);
	}
	catch(...)
	{
		model_env = nullptr;
		throw;
	}

	model_env = nullptr;
	return status;
}


// FIX ME we need to propagage the status from the whole tree, if there is an error somewhere then we should return error from the parent
bool Model::remove_tree(bool remove_whole_tree)
{
	bool result = false;
	model_env->has_primary_key_set = has_primary_key_set;

	if( !has_primary_key_set )
	{
		put_to_log(L"Morm: call remove but model doesn't have a primary key set");
		return result;
	}

	if( remove_whole_tree )
	{
		model_env->model_work_mode = MORM_MODEL_WORK_MODE_ITERATE_THROUGH_CHILDS_WITHOUT_FOREIGN_KEY;
		model_env->model_work_submode = MORM_MODEL_WORK_SUBMODE_REMOVE;
		map_fields();
	}

	if( model_connector )
	{
		model_env->model_work_mode = MORM_MODEL_WORK_MODE_GENERATING_DB_SQL;
		DbConnector * db_connector = model_connector->get_db_connector();

		// CHECK ME what if the stream is being used by something other?
		PT::TextStream * out_stream = model_connector->get_stream();

		if( db_connector && out_stream )
		{
			before_remove();
			out_stream->clear();
			result = db_connector->remove(*out_stream, *this);

			if( result )
			{
				save_mode = DO_NOTHING_ON_SAVE;
				has_primary_key_set = false;
				model_env->has_primary_key_set = false;
				after_remove();
			}
			else
			{
				after_remove_failure();
			}
		}
	}

	if( remove_whole_tree )
	{
		model_env->model_work_mode = MORM_MODEL_WORK_MODE_ITERATE_THROUGH_CHILDS_WITH_FOREIGN_KEY;
		model_env->model_work_submode = MORM_MODEL_WORK_SUBMODE_REMOVE;
		map_fields();
	}

	return result;
}




bool Model::save(ModelData & model_data, bool save_whole_tree)
{
	return save(&model_data, save_whole_tree);
}


bool Model::save(bool save_whole_tree)
{
	return save(nullptr, save_whole_tree);
}


bool Model::save(ModelData * model_data, bool save_whole_tree)
{
	ModelEnv model_env_local;
	model_env = &model_env_local;

	model_env->model_data = model_data;
	bool status = false;

	try
	{
		status = save_tree(save_whole_tree);
	}
	catch(...)
	{
		model_env = nullptr;
		throw;
	}

	model_env = nullptr;
	return status;
}


// FIX ME we need to propagage the status from the whole tree, if there is an error somewhere then we should return error from the parent
bool Model::save_tree(bool save_whole_tree)
{
	bool result = false;
	model_env->has_primary_key_set = has_primary_key_set;

	if( save_whole_tree )
	{
		if( save_mode == DO_DELETE_ON_SAVE )
			model_env->model_work_mode = MORM_MODEL_WORK_MODE_ITERATE_THROUGH_CHILDS_WITHOUT_FOREIGN_KEY;
		else
			model_env->model_work_mode = MORM_MODEL_WORK_MODE_ITERATE_THROUGH_CHILDS_WITH_FOREIGN_KEY;

		model_env->model_work_submode = MORM_MODEL_WORK_SUBMODE_SAVE;
		map_fields();
	}

	ModelEnv * old_model_env = model_env; // remove, insert or update will set model_env to nullptr

	switch( save_mode )
	{
	case DO_DELETE_ON_SAVE:
		result = remove_tree(false);
		break;

	case DO_INSERT_ON_SAVE:
		result = insert_tree(false);
		break;

	case DO_UPDATE_ON_SAVE:
		result = update_tree(false);
		break;

	case DO_NOTHING_ON_SAVE:
		result = true;
		break;
	}

	model_env = old_model_env;

	if( save_whole_tree )
	{
		if( save_mode == DO_DELETE_ON_SAVE )
			model_env->model_work_mode = MORM_MODEL_WORK_MODE_ITERATE_THROUGH_CHILDS_WITH_FOREIGN_KEY;
		else
			model_env->model_work_mode = MORM_MODEL_WORK_MODE_ITERATE_THROUGH_CHILDS_WITHOUT_FOREIGN_KEY;

		model_env->model_work_submode = MORM_MODEL_WORK_SUBMODE_SAVE;
		map_fields();
	}

	return result;
}


void Model::generate_select_columns(PT::TextStream & stream)
{
	if( model_connector && model_env )
	{
		model_env->model_work_mode = MORM_MODEL_WORK_MODE_GENERATING_DB_SQL;
		DbConnector * db_connector = model_connector->get_db_connector();

		if( db_connector )
		{
			db_connector->generate_select_columns(stream, *this);
		}
	}
}





void Model::map_values_from_query()
{
	if( model_env )
	{
		model_env->model_work_mode = MORM_MODEL_WORK_MODE_READING_VALUE_FROM_DB_RESULTSET;
		model_env->was_primary_key_read = false; // whether or not there was at least one column with primary_key flag
		model_env->has_primary_key_set = true;   // whether all primary_columns were different than null
		map_fields();
		model_env->model_work_mode = MORM_MODEL_WORK_MODE_NONE;

		if( model_env->was_primary_key_read && model_env->has_primary_key_set )
		{
			has_primary_key_set = true;
			save_mode = DO_UPDATE_ON_SAVE;
		}
		else
		{
			has_primary_key_set = false;
			save_mode = DO_NOTHING_ON_SAVE;
		}
	}
}



void Model::clear()
{
	ModelEnv model_env_local;
	model_env = &model_env_local;

	model_env->model_work_mode = MORM_MODEL_WORK_MODE_CLEARING_VALUE;

	try
	{
		map_fields();
	}
	catch(...)
	{
		model_env = nullptr;
		throw;
	}

	model_env = nullptr;
	save_mode = DO_INSERT_ON_SAVE;
	has_primary_key_set = false;
}







void Model::before_select()
{
}

void Model::before_insert()
{
}

void Model::before_update()
{
}

void Model::before_remove()
{
}

void Model::after_select()
{
}

void Model::after_insert()
{
}

void Model::after_update()
{
}

void Model::after_remove()
{
}

void Model::after_select_failure()
{
}

void Model::after_insert_failure()
{
}

void Model::after_update_failure()
{
}

void Model::after_remove_failure()
{
}

int Model::get_work_mode()
{
	if( model_env )
	{
		return model_env->model_work_mode;
	}
	else
	{
		return MORM_MODEL_WORK_MODE_NONE;
	}
}


ModelData * Model::get_model_data()
{
	if( model_env )
	{
		return model_env->model_data;
	}
	else
	{
		return nullptr;
	}
}


bool Model::is_empty_field(const wchar_t * value)
{
	return (!value || *value == '\0');
}


bool Model::is_the_same_field(const wchar_t * field1, const wchar_t * field2)
{
	if( is_empty_field(field1) && is_empty_field(field2) )
		return true;

	if( is_empty_field(field1) || is_empty_field(field2) )
		return false;

	bool the_same = false;

	while( *field1 && *field2 )
	{
		field1 += 1;
		field2 += 1;
	}

	if( *field1 == 0 && *field2 == 0 )
	{
		the_same = true;
	}

	return the_same;
}



void Model::prepare_table_names(bool prepare_table_index)
{
	DbConnector * db_connector = model_connector->get_db_connector();

	if( db_connector && model_env )
	{
		DbExpression * db_expression = db_connector->get_expression();

		if( db_expression )
		{
			table_name(model_env->table_name);
			db_expression->prepare_short_table_name(model_env->table_name, model_env->table_name_short);

			if( prepare_table_index && model_env->finder_helper )
			{
				model_env->table_index = model_env->finder_helper->add_join_table(model_env->table_name_short);
			}
		}
	}
}


void Model::put_table_name_with_index(PT::TextStream & str)
{
	if( model_env )
	{
		str << model_env->table_name_short;

		if( model_env->table_index > 1 )
		{
			str << model_env->table_index;
		}
	}
}


void Model::put_to_log(const wchar_t * str)
{
	if( model_connector )
	{
		PT::Log * log = model_connector->get_logger();

		if( log )
		{
			(*log) << str << PT::Log::logend;
		}
	}
}


void Model::put_fields_to_log(PT::Log & log, const wchar_t * db_field_name, const wchar_t * flat_field_name)
{
	bool was_db_field_put = false;
	bool was_flat_field_put = false;

	if( !is_empty_field(db_field_name) )
	{
		log << "database field name: " << db_field_name;
		was_db_field_put = true;
	}

	if( !is_empty_field(flat_field_name) )
	{
		if( was_db_field_put )
			log << ", ";

		log << "flat field name: " << flat_field_name;
		was_flat_field_put = true;
	}

	if( !was_db_field_put && !was_flat_field_put )
	{
		log << "(both database field name and flat field name are empty)";
	}
}


} // namespace